linux/drivers/infiniband/hw/cxgb4/device.c

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/*
* Copyright (c) 2009-2010 Chelsio, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/debugfs.h>
#include <linux/vmalloc.h>
#include <linux/math64.h>
#include <rdma/ib_verbs.h>
#include "iw_cxgb4.h"
#define DRV_VERSION "0.1"
MODULE_AUTHOR("Steve Wise");
MODULE_DESCRIPTION("Chelsio T4/T5 RDMA Driver");
MODULE_LICENSE("Dual BSD/GPL");
static int allow_db_fc_on_t5;
module_param(allow_db_fc_on_t5, int, 0644);
MODULE_PARM_DESC(allow_db_fc_on_t5,
"Allow DB Flow Control on T5 (default = 0)");
static int allow_db_coalescing_on_t5;
module_param(allow_db_coalescing_on_t5, int, 0644);
MODULE_PARM_DESC(allow_db_coalescing_on_t5,
"Allow DB Coalescing on T5 (default = 0)");
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
int c4iw_wr_log = 0;
module_param(c4iw_wr_log, int, 0444);
MODULE_PARM_DESC(c4iw_wr_log, "Enables logging of work request timing data.");
static int c4iw_wr_log_size_order = 12;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
module_param(c4iw_wr_log_size_order, int, 0444);
MODULE_PARM_DESC(c4iw_wr_log_size_order,
"Number of entries (log2) in the work request timing log.");
static LIST_HEAD(uld_ctx_list);
static DEFINE_MUTEX(dev_mutex);
static struct workqueue_struct *reg_workq;
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
#define DB_FC_RESUME_SIZE 64
#define DB_FC_RESUME_DELAY 1
#define DB_FC_DRAIN_THRESH 0
static struct dentry *c4iw_debugfs_root;
struct c4iw_debugfs_data {
struct c4iw_dev *devp;
char *buf;
int bufsize;
int pos;
};
static int count_idrs(int id, void *p, void *data)
{
int *countp = data;
*countp = *countp + 1;
return 0;
}
static ssize_t debugfs_read(struct file *file, char __user *buf, size_t count,
loff_t *ppos)
{
struct c4iw_debugfs_data *d = file->private_data;
return simple_read_from_buffer(buf, count, ppos, d->buf, d->pos);
}
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
void c4iw_log_wr_stats(struct t4_wq *wq, struct t4_cqe *cqe)
{
struct wr_log_entry le;
int idx;
if (!wq->rdev->wr_log)
return;
idx = (atomic_inc_return(&wq->rdev->wr_log_idx) - 1) &
(wq->rdev->wr_log_size - 1);
le.poll_sge_ts = cxgb4_read_sge_timestamp(wq->rdev->lldi.ports[0]);
le.poll_host_time = ktime_get();
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
le.valid = 1;
le.cqe_sge_ts = CQE_TS(cqe);
if (SQ_TYPE(cqe)) {
le.qid = wq->sq.qid;
le.opcode = CQE_OPCODE(cqe);
le.post_host_time = wq->sq.sw_sq[wq->sq.cidx].host_time;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
le.post_sge_ts = wq->sq.sw_sq[wq->sq.cidx].sge_ts;
le.wr_id = CQE_WRID_SQ_IDX(cqe);
} else {
le.qid = wq->rq.qid;
le.opcode = FW_RI_RECEIVE;
le.post_host_time = wq->rq.sw_rq[wq->rq.cidx].host_time;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
le.post_sge_ts = wq->rq.sw_rq[wq->rq.cidx].sge_ts;
le.wr_id = CQE_WRID_MSN(cqe);
}
wq->rdev->wr_log[idx] = le;
}
static int wr_log_show(struct seq_file *seq, void *v)
{
struct c4iw_dev *dev = seq->private;
ktime_t prev_time;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
struct wr_log_entry *lep;
int prev_time_set = 0;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
int idx, end;
#define ts2ns(ts) div64_u64((ts) * dev->rdev.lldi.cclk_ps, 1000)
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
idx = atomic_read(&dev->rdev.wr_log_idx) &
(dev->rdev.wr_log_size - 1);
end = idx - 1;
if (end < 0)
end = dev->rdev.wr_log_size - 1;
lep = &dev->rdev.wr_log[idx];
while (idx != end) {
if (lep->valid) {
if (!prev_time_set) {
prev_time_set = 1;
prev_time = lep->poll_host_time;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
}
seq_printf(seq, "%04u: nsec %llu qid %u opcode "
"%u %s 0x%x host_wr_delta nsec %llu "
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
"post_sge_ts 0x%llx cqe_sge_ts 0x%llx "
"poll_sge_ts 0x%llx post_poll_delta_ns %llu "
"cqe_poll_delta_ns %llu\n",
idx,
ktime_to_ns(ktime_sub(lep->poll_host_time,
prev_time)),
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
lep->qid, lep->opcode,
lep->opcode == FW_RI_RECEIVE ?
"msn" : "wrid",
lep->wr_id,
ktime_to_ns(ktime_sub(lep->poll_host_time,
lep->post_host_time)),
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
lep->post_sge_ts, lep->cqe_sge_ts,
lep->poll_sge_ts,
ts2ns(lep->poll_sge_ts - lep->post_sge_ts),
ts2ns(lep->poll_sge_ts - lep->cqe_sge_ts));
prev_time = lep->poll_host_time;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
}
idx++;
if (idx > (dev->rdev.wr_log_size - 1))
idx = 0;
lep = &dev->rdev.wr_log[idx];
}
#undef ts2ns
return 0;
}
static int wr_log_open(struct inode *inode, struct file *file)
{
return single_open(file, wr_log_show, inode->i_private);
}
static ssize_t wr_log_clear(struct file *file, const char __user *buf,
size_t count, loff_t *pos)
{
struct c4iw_dev *dev = ((struct seq_file *)file->private_data)->private;
int i;
if (dev->rdev.wr_log)
for (i = 0; i < dev->rdev.wr_log_size; i++)
dev->rdev.wr_log[i].valid = 0;
return count;
}
static const struct file_operations wr_log_debugfs_fops = {
.owner = THIS_MODULE,
.open = wr_log_open,
.release = single_release,
.read = seq_read,
.llseek = seq_lseek,
.write = wr_log_clear,
};
static struct sockaddr_in zero_sin = {
.sin_family = AF_INET,
};
static struct sockaddr_in6 zero_sin6 = {
.sin6_family = AF_INET6,
};
static void set_ep_sin_addrs(struct c4iw_ep *ep,
struct sockaddr_in **lsin,
struct sockaddr_in **rsin,
struct sockaddr_in **m_lsin,
struct sockaddr_in **m_rsin)
{
struct iw_cm_id *id = ep->com.cm_id;
*m_lsin = (struct sockaddr_in *)&ep->com.local_addr;
*m_rsin = (struct sockaddr_in *)&ep->com.remote_addr;
if (id) {
*lsin = (struct sockaddr_in *)&id->local_addr;
*rsin = (struct sockaddr_in *)&id->remote_addr;
} else {
*lsin = &zero_sin;
*rsin = &zero_sin;
}
}
static void set_ep_sin6_addrs(struct c4iw_ep *ep,
struct sockaddr_in6 **lsin6,
struct sockaddr_in6 **rsin6,
struct sockaddr_in6 **m_lsin6,
struct sockaddr_in6 **m_rsin6)
{
struct iw_cm_id *id = ep->com.cm_id;
*m_lsin6 = (struct sockaddr_in6 *)&ep->com.local_addr;
*m_rsin6 = (struct sockaddr_in6 *)&ep->com.remote_addr;
if (id) {
*lsin6 = (struct sockaddr_in6 *)&id->local_addr;
*rsin6 = (struct sockaddr_in6 *)&id->remote_addr;
} else {
*lsin6 = &zero_sin6;
*rsin6 = &zero_sin6;
}
}
static int dump_qp(int id, void *p, void *data)
{
struct c4iw_qp *qp = p;
struct c4iw_debugfs_data *qpd = data;
int space;
int cc;
if (id != qp->wq.sq.qid)
return 0;
space = qpd->bufsize - qpd->pos - 1;
if (space == 0)
return 1;
if (qp->ep) {
struct c4iw_ep *ep = qp->ep;
if (ep->com.local_addr.ss_family == AF_INET) {
struct sockaddr_in *lsin;
struct sockaddr_in *rsin;
struct sockaddr_in *m_lsin;
struct sockaddr_in *m_rsin;
set_ep_sin_addrs(ep, &lsin, &rsin, &m_lsin, &m_rsin);
cc = snprintf(qpd->buf + qpd->pos, space,
"rc qp sq id %u %s id %u state %u "
"onchip %u ep tid %u state %u "
"%pI4:%u/%u->%pI4:%u/%u\n",
qp->wq.sq.qid, qp->srq ? "srq" : "rq",
qp->srq ? qp->srq->idx : qp->wq.rq.qid,
(int)qp->attr.state,
qp->wq.sq.flags & T4_SQ_ONCHIP,
ep->hwtid, (int)ep->com.state,
&lsin->sin_addr, ntohs(lsin->sin_port),
ntohs(m_lsin->sin_port),
&rsin->sin_addr, ntohs(rsin->sin_port),
ntohs(m_rsin->sin_port));
} else {
struct sockaddr_in6 *lsin6;
struct sockaddr_in6 *rsin6;
struct sockaddr_in6 *m_lsin6;
struct sockaddr_in6 *m_rsin6;
set_ep_sin6_addrs(ep, &lsin6, &rsin6, &m_lsin6,
&m_rsin6);
cc = snprintf(qpd->buf + qpd->pos, space,
"rc qp sq id %u rq id %u state %u "
"onchip %u ep tid %u state %u "
"%pI6:%u/%u->%pI6:%u/%u\n",
qp->wq.sq.qid, qp->wq.rq.qid,
(int)qp->attr.state,
qp->wq.sq.flags & T4_SQ_ONCHIP,
ep->hwtid, (int)ep->com.state,
&lsin6->sin6_addr,
ntohs(lsin6->sin6_port),
ntohs(m_lsin6->sin6_port),
&rsin6->sin6_addr,
ntohs(rsin6->sin6_port),
ntohs(m_rsin6->sin6_port));
}
} else
cc = snprintf(qpd->buf + qpd->pos, space,
"qp sq id %u rq id %u state %u onchip %u\n",
qp->wq.sq.qid, qp->wq.rq.qid,
(int)qp->attr.state,
qp->wq.sq.flags & T4_SQ_ONCHIP);
if (cc < space)
qpd->pos += cc;
return 0;
}
static int qp_release(struct inode *inode, struct file *file)
{
struct c4iw_debugfs_data *qpd = file->private_data;
if (!qpd) {
pr_info("%s null qpd?\n", __func__);
return 0;
}
vfree(qpd->buf);
kfree(qpd);
return 0;
}
static int qp_open(struct inode *inode, struct file *file)
{
struct c4iw_debugfs_data *qpd;
int count = 1;
qpd = kmalloc(sizeof *qpd, GFP_KERNEL);
if (!qpd)
return -ENOMEM;
qpd->devp = inode->i_private;
qpd->pos = 0;
spin_lock_irq(&qpd->devp->lock);
idr_for_each(&qpd->devp->qpidr, count_idrs, &count);
spin_unlock_irq(&qpd->devp->lock);
qpd->bufsize = count * 180;
qpd->buf = vmalloc(qpd->bufsize);
if (!qpd->buf) {
kfree(qpd);
return -ENOMEM;
}
spin_lock_irq(&qpd->devp->lock);
idr_for_each(&qpd->devp->qpidr, dump_qp, qpd);
spin_unlock_irq(&qpd->devp->lock);
qpd->buf[qpd->pos++] = 0;
file->private_data = qpd;
return 0;
}
static const struct file_operations qp_debugfs_fops = {
.owner = THIS_MODULE,
.open = qp_open,
.release = qp_release,
.read = debugfs_read,
.llseek = default_llseek,
};
static int dump_stag(int id, void *p, void *data)
{
struct c4iw_debugfs_data *stagd = data;
int space;
int cc;
struct fw_ri_tpte tpte;
int ret;
space = stagd->bufsize - stagd->pos - 1;
if (space == 0)
return 1;
ret = cxgb4_read_tpte(stagd->devp->rdev.lldi.ports[0], (u32)id<<8,
(__be32 *)&tpte);
if (ret) {
dev_err(&stagd->devp->rdev.lldi.pdev->dev,
"%s cxgb4_read_tpte err %d\n", __func__, ret);
return ret;
}
cc = snprintf(stagd->buf + stagd->pos, space,
"stag: idx 0x%x valid %d key 0x%x state %d pdid %d "
"perm 0x%x ps %d len 0x%llx va 0x%llx\n",
(u32)id<<8,
FW_RI_TPTE_VALID_G(ntohl(tpte.valid_to_pdid)),
FW_RI_TPTE_STAGKEY_G(ntohl(tpte.valid_to_pdid)),
FW_RI_TPTE_STAGSTATE_G(ntohl(tpte.valid_to_pdid)),
FW_RI_TPTE_PDID_G(ntohl(tpte.valid_to_pdid)),
FW_RI_TPTE_PERM_G(ntohl(tpte.locread_to_qpid)),
FW_RI_TPTE_PS_G(ntohl(tpte.locread_to_qpid)),
((u64)ntohl(tpte.len_hi) << 32) | ntohl(tpte.len_lo),
((u64)ntohl(tpte.va_hi) << 32) | ntohl(tpte.va_lo_fbo));
if (cc < space)
stagd->pos += cc;
return 0;
}
static int stag_release(struct inode *inode, struct file *file)
{
struct c4iw_debugfs_data *stagd = file->private_data;
if (!stagd) {
pr_info("%s null stagd?\n", __func__);
return 0;
}
vfree(stagd->buf);
kfree(stagd);
return 0;
}
static int stag_open(struct inode *inode, struct file *file)
{
struct c4iw_debugfs_data *stagd;
int ret = 0;
int count = 1;
stagd = kmalloc(sizeof *stagd, GFP_KERNEL);
if (!stagd) {
ret = -ENOMEM;
goto out;
}
stagd->devp = inode->i_private;
stagd->pos = 0;
spin_lock_irq(&stagd->devp->lock);
idr_for_each(&stagd->devp->mmidr, count_idrs, &count);
spin_unlock_irq(&stagd->devp->lock);
stagd->bufsize = count * 256;
stagd->buf = vmalloc(stagd->bufsize);
if (!stagd->buf) {
ret = -ENOMEM;
goto err1;
}
spin_lock_irq(&stagd->devp->lock);
idr_for_each(&stagd->devp->mmidr, dump_stag, stagd);
spin_unlock_irq(&stagd->devp->lock);
stagd->buf[stagd->pos++] = 0;
file->private_data = stagd;
goto out;
err1:
kfree(stagd);
out:
return ret;
}
static const struct file_operations stag_debugfs_fops = {
.owner = THIS_MODULE,
.open = stag_open,
.release = stag_release,
.read = debugfs_read,
.llseek = default_llseek,
};
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
static char *db_state_str[] = {"NORMAL", "FLOW_CONTROL", "RECOVERY", "STOPPED"};
static int stats_show(struct seq_file *seq, void *v)
{
struct c4iw_dev *dev = seq->private;
seq_printf(seq, " Object: %10s %10s %10s %10s\n", "Total", "Current",
"Max", "Fail");
seq_printf(seq, " PDID: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.pd.total, dev->rdev.stats.pd.cur,
dev->rdev.stats.pd.max, dev->rdev.stats.pd.fail);
seq_printf(seq, " QID: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.qid.total, dev->rdev.stats.qid.cur,
dev->rdev.stats.qid.max, dev->rdev.stats.qid.fail);
seq_printf(seq, " SRQS: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.srqt.total, dev->rdev.stats.srqt.cur,
dev->rdev.stats.srqt.max, dev->rdev.stats.srqt.fail);
seq_printf(seq, " TPTMEM: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.stag.total, dev->rdev.stats.stag.cur,
dev->rdev.stats.stag.max, dev->rdev.stats.stag.fail);
seq_printf(seq, " PBLMEM: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.pbl.total, dev->rdev.stats.pbl.cur,
dev->rdev.stats.pbl.max, dev->rdev.stats.pbl.fail);
seq_printf(seq, " RQTMEM: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.rqt.total, dev->rdev.stats.rqt.cur,
dev->rdev.stats.rqt.max, dev->rdev.stats.rqt.fail);
seq_printf(seq, " OCQPMEM: %10llu %10llu %10llu %10llu\n",
dev->rdev.stats.ocqp.total, dev->rdev.stats.ocqp.cur,
dev->rdev.stats.ocqp.max, dev->rdev.stats.ocqp.fail);
seq_printf(seq, " DB FULL: %10llu\n", dev->rdev.stats.db_full);
seq_printf(seq, " DB EMPTY: %10llu\n", dev->rdev.stats.db_empty);
seq_printf(seq, " DB DROP: %10llu\n", dev->rdev.stats.db_drop);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
seq_printf(seq, " DB State: %s Transitions %llu FC Interruptions %llu\n",
db_state_str[dev->db_state],
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
dev->rdev.stats.db_state_transitions,
dev->rdev.stats.db_fc_interruptions);
seq_printf(seq, "TCAM_FULL: %10llu\n", dev->rdev.stats.tcam_full);
seq_printf(seq, "ACT_OFLD_CONN_FAILS: %10llu\n",
dev->rdev.stats.act_ofld_conn_fails);
seq_printf(seq, "PAS_OFLD_CONN_FAILS: %10llu\n",
dev->rdev.stats.pas_ofld_conn_fails);
seq_printf(seq, "NEG_ADV_RCVD: %10llu\n", dev->rdev.stats.neg_adv);
seq_printf(seq, "AVAILABLE IRD: %10u\n", dev->avail_ird);
return 0;
}
static int stats_open(struct inode *inode, struct file *file)
{
return single_open(file, stats_show, inode->i_private);
}
static ssize_t stats_clear(struct file *file, const char __user *buf,
size_t count, loff_t *pos)
{
struct c4iw_dev *dev = ((struct seq_file *)file->private_data)->private;
mutex_lock(&dev->rdev.stats.lock);
dev->rdev.stats.pd.max = 0;
dev->rdev.stats.pd.fail = 0;
dev->rdev.stats.qid.max = 0;
dev->rdev.stats.qid.fail = 0;
dev->rdev.stats.stag.max = 0;
dev->rdev.stats.stag.fail = 0;
dev->rdev.stats.pbl.max = 0;
dev->rdev.stats.pbl.fail = 0;
dev->rdev.stats.rqt.max = 0;
dev->rdev.stats.rqt.fail = 0;
dev->rdev.stats.rqt.max = 0;
dev->rdev.stats.rqt.fail = 0;
dev->rdev.stats.ocqp.max = 0;
dev->rdev.stats.ocqp.fail = 0;
dev->rdev.stats.db_full = 0;
dev->rdev.stats.db_empty = 0;
dev->rdev.stats.db_drop = 0;
dev->rdev.stats.db_state_transitions = 0;
dev->rdev.stats.tcam_full = 0;
dev->rdev.stats.act_ofld_conn_fails = 0;
dev->rdev.stats.pas_ofld_conn_fails = 0;
mutex_unlock(&dev->rdev.stats.lock);
return count;
}
static const struct file_operations stats_debugfs_fops = {
.owner = THIS_MODULE,
.open = stats_open,
.release = single_release,
.read = seq_read,
.llseek = seq_lseek,
.write = stats_clear,
};
static int dump_ep(int id, void *p, void *data)
{
struct c4iw_ep *ep = p;
struct c4iw_debugfs_data *epd = data;
int space;
int cc;
space = epd->bufsize - epd->pos - 1;
if (space == 0)
return 1;
if (ep->com.local_addr.ss_family == AF_INET) {
struct sockaddr_in *lsin;
struct sockaddr_in *rsin;
struct sockaddr_in *m_lsin;
struct sockaddr_in *m_rsin;
set_ep_sin_addrs(ep, &lsin, &rsin, &m_lsin, &m_rsin);
cc = snprintf(epd->buf + epd->pos, space,
"ep %p cm_id %p qp %p state %d flags 0x%lx "
"history 0x%lx hwtid %d atid %d "
"conn_na %u abort_na %u "
"%pI4:%d/%d <-> %pI4:%d/%d\n",
ep, ep->com.cm_id, ep->com.qp,
(int)ep->com.state, ep->com.flags,
ep->com.history, ep->hwtid, ep->atid,
ep->stats.connect_neg_adv,
ep->stats.abort_neg_adv,
&lsin->sin_addr, ntohs(lsin->sin_port),
ntohs(m_lsin->sin_port),
&rsin->sin_addr, ntohs(rsin->sin_port),
ntohs(m_rsin->sin_port));
} else {
struct sockaddr_in6 *lsin6;
struct sockaddr_in6 *rsin6;
struct sockaddr_in6 *m_lsin6;
struct sockaddr_in6 *m_rsin6;
set_ep_sin6_addrs(ep, &lsin6, &rsin6, &m_lsin6, &m_rsin6);
cc = snprintf(epd->buf + epd->pos, space,
"ep %p cm_id %p qp %p state %d flags 0x%lx "
"history 0x%lx hwtid %d atid %d "
"conn_na %u abort_na %u "
"%pI6:%d/%d <-> %pI6:%d/%d\n",
ep, ep->com.cm_id, ep->com.qp,
(int)ep->com.state, ep->com.flags,
ep->com.history, ep->hwtid, ep->atid,
ep->stats.connect_neg_adv,
ep->stats.abort_neg_adv,
&lsin6->sin6_addr, ntohs(lsin6->sin6_port),
ntohs(m_lsin6->sin6_port),
&rsin6->sin6_addr, ntohs(rsin6->sin6_port),
ntohs(m_rsin6->sin6_port));
}
if (cc < space)
epd->pos += cc;
return 0;
}
static int dump_listen_ep(int id, void *p, void *data)
{
struct c4iw_listen_ep *ep = p;
struct c4iw_debugfs_data *epd = data;
int space;
int cc;
space = epd->bufsize - epd->pos - 1;
if (space == 0)
return 1;
if (ep->com.local_addr.ss_family == AF_INET) {
struct sockaddr_in *lsin = (struct sockaddr_in *)
&ep->com.cm_id->local_addr;
struct sockaddr_in *m_lsin = (struct sockaddr_in *)
&ep->com.cm_id->m_local_addr;
cc = snprintf(epd->buf + epd->pos, space,
"ep %p cm_id %p state %d flags 0x%lx stid %d "
"backlog %d %pI4:%d/%d\n",
ep, ep->com.cm_id, (int)ep->com.state,
ep->com.flags, ep->stid, ep->backlog,
&lsin->sin_addr, ntohs(lsin->sin_port),
ntohs(m_lsin->sin_port));
} else {
struct sockaddr_in6 *lsin6 = (struct sockaddr_in6 *)
&ep->com.cm_id->local_addr;
struct sockaddr_in6 *m_lsin6 = (struct sockaddr_in6 *)
&ep->com.cm_id->m_local_addr;
cc = snprintf(epd->buf + epd->pos, space,
"ep %p cm_id %p state %d flags 0x%lx stid %d "
"backlog %d %pI6:%d/%d\n",
ep, ep->com.cm_id, (int)ep->com.state,
ep->com.flags, ep->stid, ep->backlog,
&lsin6->sin6_addr, ntohs(lsin6->sin6_port),
ntohs(m_lsin6->sin6_port));
}
if (cc < space)
epd->pos += cc;
return 0;
}
static int ep_release(struct inode *inode, struct file *file)
{
struct c4iw_debugfs_data *epd = file->private_data;
if (!epd) {
pr_info("%s null qpd?\n", __func__);
return 0;
}
vfree(epd->buf);
kfree(epd);
return 0;
}
static int ep_open(struct inode *inode, struct file *file)
{
struct c4iw_debugfs_data *epd;
int ret = 0;
int count = 1;
epd = kmalloc(sizeof(*epd), GFP_KERNEL);
if (!epd) {
ret = -ENOMEM;
goto out;
}
epd->devp = inode->i_private;
epd->pos = 0;
spin_lock_irq(&epd->devp->lock);
idr_for_each(&epd->devp->hwtid_idr, count_idrs, &count);
idr_for_each(&epd->devp->atid_idr, count_idrs, &count);
idr_for_each(&epd->devp->stid_idr, count_idrs, &count);
spin_unlock_irq(&epd->devp->lock);
epd->bufsize = count * 240;
epd->buf = vmalloc(epd->bufsize);
if (!epd->buf) {
ret = -ENOMEM;
goto err1;
}
spin_lock_irq(&epd->devp->lock);
idr_for_each(&epd->devp->hwtid_idr, dump_ep, epd);
idr_for_each(&epd->devp->atid_idr, dump_ep, epd);
idr_for_each(&epd->devp->stid_idr, dump_listen_ep, epd);
spin_unlock_irq(&epd->devp->lock);
file->private_data = epd;
goto out;
err1:
kfree(epd);
out:
return ret;
}
static const struct file_operations ep_debugfs_fops = {
.owner = THIS_MODULE,
.open = ep_open,
.release = ep_release,
.read = debugfs_read,
};
static int setup_debugfs(struct c4iw_dev *devp)
{
if (!devp->debugfs_root)
return -1;
debugfs_create_file_size("qps", S_IWUSR, devp->debugfs_root,
(void *)devp, &qp_debugfs_fops, 4096);
debugfs_create_file_size("stags", S_IWUSR, devp->debugfs_root,
(void *)devp, &stag_debugfs_fops, 4096);
debugfs_create_file_size("stats", S_IWUSR, devp->debugfs_root,
(void *)devp, &stats_debugfs_fops, 4096);
debugfs_create_file_size("eps", S_IWUSR, devp->debugfs_root,
(void *)devp, &ep_debugfs_fops, 4096);
if (c4iw_wr_log)
debugfs_create_file_size("wr_log", S_IWUSR, devp->debugfs_root,
(void *)devp, &wr_log_debugfs_fops, 4096);
return 0;
}
void c4iw_release_dev_ucontext(struct c4iw_rdev *rdev,
struct c4iw_dev_ucontext *uctx)
{
struct list_head *pos, *nxt;
struct c4iw_qid_list *entry;
mutex_lock(&uctx->lock);
list_for_each_safe(pos, nxt, &uctx->qpids) {
entry = list_entry(pos, struct c4iw_qid_list, entry);
list_del_init(&entry->entry);
if (!(entry->qid & rdev->qpmask)) {
c4iw_put_resource(&rdev->resource.qid_table,
entry->qid);
mutex_lock(&rdev->stats.lock);
rdev->stats.qid.cur -= rdev->qpmask + 1;
mutex_unlock(&rdev->stats.lock);
}
kfree(entry);
}
list_for_each_safe(pos, nxt, &uctx->cqids) {
entry = list_entry(pos, struct c4iw_qid_list, entry);
list_del_init(&entry->entry);
kfree(entry);
}
mutex_unlock(&uctx->lock);
}
void c4iw_init_dev_ucontext(struct c4iw_rdev *rdev,
struct c4iw_dev_ucontext *uctx)
{
INIT_LIST_HEAD(&uctx->qpids);
INIT_LIST_HEAD(&uctx->cqids);
mutex_init(&uctx->lock);
}
/* Caller takes care of locking if needed */
static int c4iw_rdev_open(struct c4iw_rdev *rdev)
{
int err;
c4iw_init_dev_ucontext(rdev, &rdev->uctx);
/*
* This implementation assumes udb_density == ucq_density! Eventually
* we might need to support this but for now fail the open. Also the
* cqid and qpid range must match for now.
*/
if (rdev->lldi.udb_density != rdev->lldi.ucq_density) {
pr_err("%s: unsupported udb/ucq densities %u/%u\n",
pci_name(rdev->lldi.pdev), rdev->lldi.udb_density,
rdev->lldi.ucq_density);
return -EINVAL;
}
if (rdev->lldi.vr->qp.start != rdev->lldi.vr->cq.start ||
rdev->lldi.vr->qp.size != rdev->lldi.vr->cq.size) {
pr_err("%s: unsupported qp and cq id ranges qp start %u size %u cq start %u size %u\n",
pci_name(rdev->lldi.pdev), rdev->lldi.vr->qp.start,
rdev->lldi.vr->qp.size, rdev->lldi.vr->cq.size,
rdev->lldi.vr->cq.size);
return -EINVAL;
}
rdev->qpmask = rdev->lldi.udb_density - 1;
rdev->cqmask = rdev->lldi.ucq_density - 1;
pr_debug("dev %s stag start 0x%0x size 0x%0x num stags %d pbl start 0x%0x size 0x%0x rq start 0x%0x size 0x%0x qp qid start %u size %u cq qid start %u size %u srq size %u\n",
pci_name(rdev->lldi.pdev), rdev->lldi.vr->stag.start,
rdev->lldi.vr->stag.size, c4iw_num_stags(rdev),
rdev->lldi.vr->pbl.start,
rdev->lldi.vr->pbl.size, rdev->lldi.vr->rq.start,
rdev->lldi.vr->rq.size,
rdev->lldi.vr->qp.start,
rdev->lldi.vr->qp.size,
rdev->lldi.vr->cq.start,
rdev->lldi.vr->cq.size,
rdev->lldi.vr->srq.size);
pr_debug("udb %pR db_reg %p gts_reg %p qpmask 0x%x cqmask 0x%x\n",
&rdev->lldi.pdev->resource[2],
rdev->lldi.db_reg, rdev->lldi.gts_reg,
rdev->qpmask, rdev->cqmask);
if (c4iw_num_stags(rdev) == 0)
return -EINVAL;
rdev->stats.pd.total = T4_MAX_NUM_PD;
rdev->stats.stag.total = rdev->lldi.vr->stag.size;
rdev->stats.pbl.total = rdev->lldi.vr->pbl.size;
rdev->stats.rqt.total = rdev->lldi.vr->rq.size;
rdev->stats.srqt.total = rdev->lldi.vr->srq.size;
rdev->stats.ocqp.total = rdev->lldi.vr->ocq.size;
rdev->stats.qid.total = rdev->lldi.vr->qp.size;
err = c4iw_init_resource(rdev, c4iw_num_stags(rdev),
T4_MAX_NUM_PD, rdev->lldi.vr->srq.size);
if (err) {
pr_err("error %d initializing resources\n", err);
return err;
}
err = c4iw_pblpool_create(rdev);
if (err) {
pr_err("error %d initializing pbl pool\n", err);
goto destroy_resource;
}
err = c4iw_rqtpool_create(rdev);
if (err) {
pr_err("error %d initializing rqt pool\n", err);
goto destroy_pblpool;
}
err = c4iw_ocqp_pool_create(rdev);
if (err) {
pr_err("error %d initializing ocqp pool\n", err);
goto destroy_rqtpool;
}
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
rdev->status_page = (struct t4_dev_status_page *)
__get_free_page(GFP_KERNEL);
if (!rdev->status_page) {
err = -ENOMEM;
goto destroy_ocqp_pool;
}
rdev->status_page->qp_start = rdev->lldi.vr->qp.start;
rdev->status_page->qp_size = rdev->lldi.vr->qp.size;
rdev->status_page->cq_start = rdev->lldi.vr->cq.start;
rdev->status_page->cq_size = rdev->lldi.vr->cq.size;
rdev->status_page->write_cmpl_supported = rdev->lldi.write_cmpl_support;
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
if (c4iw_wr_log) {
treewide: kzalloc() -> kcalloc() The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 21:03:40 +00:00
rdev->wr_log = kcalloc(1 << c4iw_wr_log_size_order,
sizeof(*rdev->wr_log),
GFP_KERNEL);
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
if (rdev->wr_log) {
rdev->wr_log_size = 1 << c4iw_wr_log_size_order;
atomic_set(&rdev->wr_log_idx, 0);
}
}
rdev->free_workq = create_singlethread_workqueue("iw_cxgb4_free");
if (!rdev->free_workq) {
err = -ENOMEM;
goto err_free_status_page_and_wr_log;
}
rdev->status_page->db_off = 0;
init_completion(&rdev->rqt_compl);
init_completion(&rdev->pbl_compl);
kref_init(&rdev->rqt_kref);
kref_init(&rdev->pbl_kref);
return 0;
err_free_status_page_and_wr_log:
if (c4iw_wr_log && rdev->wr_log)
kfree(rdev->wr_log);
free_page((unsigned long)rdev->status_page);
destroy_ocqp_pool:
c4iw_ocqp_pool_destroy(rdev);
destroy_rqtpool:
c4iw_rqtpool_destroy(rdev);
destroy_pblpool:
c4iw_pblpool_destroy(rdev);
destroy_resource:
c4iw_destroy_resource(&rdev->resource);
return err;
}
static void c4iw_rdev_close(struct c4iw_rdev *rdev)
{
cxgb4/iw_cxgb4: work request logging feature This commit enhances the iwarp driver to optionally keep a log of rdma work request timining data for kernel mode QPs. If iw_cxgb4 module option c4iw_wr_log is set to non-zero, each work request is tracked and timing data maintained in a rolling log that is 4096 entries deep by default. Module option c4iw_wr_log_size_order allows specifing a log2 size to use instead of the default order of 12 (4096 entries). Both module options are read-only and must be passed in at module load time to set them. IE: modprobe iw_cxgb4 c4iw_wr_log=1 c4iw_wr_log_size_order=10 The timing data is viewable via the iw_cxgb4 debugfs file "wr_log". Writing anything to this file will clear all the timing data. Data tracked includes: - The host time when the work request was posted, just before ringing the doorbell. The host time when the completion was polled by the application. This is also the time the log entry is created. The delta of these two times is the amount of time took processing the work request. - The qid of the EQ used to post the work request. - The work request opcode. - The cqe wr_id field. For sq completions requests this is the swsqe index. For recv completions this is the MSN of the ingress SEND. This value can be used to match log entries from this log with firmware flowc event entries. - The sge timestamp value just before ringing the doorbell when posting, the sge timestamp value just after polling the completion, and CQE.timestamp field from the completion itself. With these three timestamps we can track the latency from post to poll, and the amount of time the completion resided in the CQ before being reaped by the application. With debug firmware, the sge timestamp is also logged by firmware in its flowc history so that we can compute the latency from posting the work request until the firmware sees it. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-14 16:04:54 +00:00
kfree(rdev->wr_log);
c4iw_release_dev_ucontext(rdev, &rdev->uctx);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
free_page((unsigned long)rdev->status_page);
c4iw_pblpool_destroy(rdev);
c4iw_rqtpool_destroy(rdev);
wait_for_completion(&rdev->pbl_compl);
wait_for_completion(&rdev->rqt_compl);
c4iw_ocqp_pool_destroy(rdev);
destroy_workqueue(rdev->free_workq);
c4iw_destroy_resource(&rdev->resource);
}
void c4iw_dealloc(struct uld_ctx *ctx)
{
c4iw_rdev_close(&ctx->dev->rdev);
WARN_ON_ONCE(!idr_is_empty(&ctx->dev->cqidr));
idr_destroy(&ctx->dev->cqidr);
WARN_ON_ONCE(!idr_is_empty(&ctx->dev->qpidr));
idr_destroy(&ctx->dev->qpidr);
WARN_ON_ONCE(!idr_is_empty(&ctx->dev->mmidr));
idr_destroy(&ctx->dev->mmidr);
wait_event(ctx->dev->wait, idr_is_empty(&ctx->dev->hwtid_idr));
idr_destroy(&ctx->dev->hwtid_idr);
idr_destroy(&ctx->dev->stid_idr);
idr_destroy(&ctx->dev->atid_idr);
if (ctx->dev->rdev.bar2_kva)
iounmap(ctx->dev->rdev.bar2_kva);
if (ctx->dev->rdev.oc_mw_kva)
iounmap(ctx->dev->rdev.oc_mw_kva);
ib_dealloc_device(&ctx->dev->ibdev);
ctx->dev = NULL;
}
static void c4iw_remove(struct uld_ctx *ctx)
{
pr_debug("c4iw_dev %p\n", ctx->dev);
c4iw_unregister_device(ctx->dev);
c4iw_dealloc(ctx);
}
static int rdma_supported(const struct cxgb4_lld_info *infop)
{
return infop->vr->stag.size > 0 && infop->vr->pbl.size > 0 &&
infop->vr->rq.size > 0 && infop->vr->qp.size > 0 &&
infop->vr->cq.size > 0;
}
static struct c4iw_dev *c4iw_alloc(const struct cxgb4_lld_info *infop)
{
struct c4iw_dev *devp;
int ret;
if (!rdma_supported(infop)) {
pr_info("%s: RDMA not supported on this device\n",
pci_name(infop->pdev));
return ERR_PTR(-ENOSYS);
}
if (!ocqp_supported(infop))
pr_info("%s: On-Chip Queues not supported on this device\n",
pci_name(infop->pdev));
devp = (struct c4iw_dev *)ib_alloc_device(sizeof(*devp));
if (!devp) {
pr_err("Cannot allocate ib device\n");
return ERR_PTR(-ENOMEM);
}
devp->rdev.lldi = *infop;
/* init various hw-queue params based on lld info */
pr_debug("Ing. padding boundary is %d, egrsstatuspagesize = %d\n",
devp->rdev.lldi.sge_ingpadboundary,
devp->rdev.lldi.sge_egrstatuspagesize);
devp->rdev.hw_queue.t4_eq_status_entries =
devp->rdev.lldi.sge_egrstatuspagesize / 64;
devp->rdev.hw_queue.t4_max_eq_size = 65520;
devp->rdev.hw_queue.t4_max_iq_size = 65520;
devp->rdev.hw_queue.t4_max_rq_size = 8192 -
devp->rdev.hw_queue.t4_eq_status_entries - 1;
devp->rdev.hw_queue.t4_max_sq_size =
devp->rdev.hw_queue.t4_max_eq_size -
devp->rdev.hw_queue.t4_eq_status_entries - 1;
devp->rdev.hw_queue.t4_max_qp_depth =
devp->rdev.hw_queue.t4_max_rq_size;
devp->rdev.hw_queue.t4_max_cq_depth =
devp->rdev.hw_queue.t4_max_iq_size - 2;
devp->rdev.hw_queue.t4_stat_len =
devp->rdev.lldi.sge_egrstatuspagesize;
/*
* For T5/T6 devices, we map all of BAR2 with WC.
* For T4 devices with onchip qp mem, we map only that part
* of BAR2 with WC.
*/
devp->rdev.bar2_pa = pci_resource_start(devp->rdev.lldi.pdev, 2);
if (!is_t4(devp->rdev.lldi.adapter_type)) {
devp->rdev.bar2_kva = ioremap_wc(devp->rdev.bar2_pa,
pci_resource_len(devp->rdev.lldi.pdev, 2));
if (!devp->rdev.bar2_kva) {
pr_err("Unable to ioremap BAR2\n");
ib_dealloc_device(&devp->ibdev);
return ERR_PTR(-EINVAL);
}
} else if (ocqp_supported(infop)) {
devp->rdev.oc_mw_pa =
pci_resource_start(devp->rdev.lldi.pdev, 2) +
pci_resource_len(devp->rdev.lldi.pdev, 2) -
roundup_pow_of_two(devp->rdev.lldi.vr->ocq.size);
devp->rdev.oc_mw_kva = ioremap_wc(devp->rdev.oc_mw_pa,
devp->rdev.lldi.vr->ocq.size);
if (!devp->rdev.oc_mw_kva) {
pr_err("Unable to ioremap onchip mem\n");
ib_dealloc_device(&devp->ibdev);
return ERR_PTR(-EINVAL);
}
}
pr_debug("ocq memory: hw_start 0x%x size %u mw_pa 0x%lx mw_kva %p\n",
devp->rdev.lldi.vr->ocq.start, devp->rdev.lldi.vr->ocq.size,
devp->rdev.oc_mw_pa, devp->rdev.oc_mw_kva);
ret = c4iw_rdev_open(&devp->rdev);
if (ret) {
pr_err("Unable to open CXIO rdev err %d\n", ret);
ib_dealloc_device(&devp->ibdev);
return ERR_PTR(ret);
}
idr_init(&devp->cqidr);
idr_init(&devp->qpidr);
idr_init(&devp->mmidr);
idr_init(&devp->hwtid_idr);
idr_init(&devp->stid_idr);
idr_init(&devp->atid_idr);
spin_lock_init(&devp->lock);
mutex_init(&devp->rdev.stats.lock);
mutex_init(&devp->db_mutex);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
INIT_LIST_HEAD(&devp->db_fc_list);
init_waitqueue_head(&devp->wait);
devp->avail_ird = devp->rdev.lldi.max_ird_adapter;
if (c4iw_debugfs_root) {
devp->debugfs_root = debugfs_create_dir(
pci_name(devp->rdev.lldi.pdev),
c4iw_debugfs_root);
setup_debugfs(devp);
}
return devp;
}
static void *c4iw_uld_add(const struct cxgb4_lld_info *infop)
{
struct uld_ctx *ctx;
static int vers_printed;
int i;
if (!vers_printed++)
pr_info("Chelsio T4/T5 RDMA Driver - version %s\n",
DRV_VERSION);
ctx = kzalloc(sizeof *ctx, GFP_KERNEL);
if (!ctx) {
ctx = ERR_PTR(-ENOMEM);
goto out;
}
ctx->lldi = *infop;
pr_debug("found device %s nchan %u nrxq %u ntxq %u nports %u\n",
pci_name(ctx->lldi.pdev),
ctx->lldi.nchan, ctx->lldi.nrxq,
ctx->lldi.ntxq, ctx->lldi.nports);
mutex_lock(&dev_mutex);
list_add_tail(&ctx->entry, &uld_ctx_list);
mutex_unlock(&dev_mutex);
for (i = 0; i < ctx->lldi.nrxq; i++)
pr_debug("rxqid[%u] %u\n", i, ctx->lldi.rxq_ids[i]);
out:
return ctx;
}
static inline struct sk_buff *copy_gl_to_skb_pkt(const struct pkt_gl *gl,
const __be64 *rsp,
u32 pktshift)
{
struct sk_buff *skb;
/*
* Allocate space for cpl_pass_accept_req which will be synthesized by
* driver. Once the driver synthesizes the request the skb will go
* through the regular cpl_pass_accept_req processing.
* The math here assumes sizeof cpl_pass_accept_req >= sizeof
* cpl_rx_pkt.
*/
skb = alloc_skb(gl->tot_len + sizeof(struct cpl_pass_accept_req) +
sizeof(struct rss_header) - pktshift, GFP_ATOMIC);
if (unlikely(!skb))
return NULL;
__skb_put(skb, gl->tot_len + sizeof(struct cpl_pass_accept_req) +
sizeof(struct rss_header) - pktshift);
/*
* This skb will contain:
* rss_header from the rspq descriptor (1 flit)
* cpl_rx_pkt struct from the rspq descriptor (2 flits)
* space for the difference between the size of an
* rx_pkt and pass_accept_req cpl (1 flit)
* the packet data from the gl
*/
skb_copy_to_linear_data(skb, rsp, sizeof(struct cpl_pass_accept_req) +
sizeof(struct rss_header));
skb_copy_to_linear_data_offset(skb, sizeof(struct rss_header) +
sizeof(struct cpl_pass_accept_req),
gl->va + pktshift,
gl->tot_len - pktshift);
return skb;
}
static inline int recv_rx_pkt(struct c4iw_dev *dev, const struct pkt_gl *gl,
const __be64 *rsp)
{
unsigned int opcode = *(u8 *)rsp;
struct sk_buff *skb;
if (opcode != CPL_RX_PKT)
goto out;
skb = copy_gl_to_skb_pkt(gl , rsp, dev->rdev.lldi.sge_pktshift);
if (skb == NULL)
goto out;
if (c4iw_handlers[opcode] == NULL) {
pr_info("%s no handler opcode 0x%x...\n", __func__, opcode);
kfree_skb(skb);
goto out;
}
c4iw_handlers[opcode](dev, skb);
return 1;
out:
return 0;
}
static int c4iw_uld_rx_handler(void *handle, const __be64 *rsp,
const struct pkt_gl *gl)
{
struct uld_ctx *ctx = handle;
struct c4iw_dev *dev = ctx->dev;
struct sk_buff *skb;
u8 opcode;
if (gl == NULL) {
/* omit RSS and rsp_ctrl at end of descriptor */
unsigned int len = 64 - sizeof(struct rsp_ctrl) - 8;
skb = alloc_skb(256, GFP_ATOMIC);
if (!skb)
goto nomem;
__skb_put(skb, len);
skb_copy_to_linear_data(skb, &rsp[1], len);
} else if (gl == CXGB4_MSG_AN) {
const struct rsp_ctrl *rc = (void *)rsp;
u32 qid = be32_to_cpu(rc->pldbuflen_qid);
c4iw_ev_handler(dev, qid);
return 0;
} else if (unlikely(*(u8 *)rsp != *(u8 *)gl->va)) {
if (recv_rx_pkt(dev, gl, rsp))
return 0;
pr_info("%s: unexpected FL contents at %p, RSS %#llx, FL %#llx, len %u\n",
pci_name(ctx->lldi.pdev), gl->va,
be64_to_cpu(*rsp),
be64_to_cpu(*(__force __be64 *)gl->va),
gl->tot_len);
return 0;
} else {
skb = cxgb4_pktgl_to_skb(gl, 128, 128);
if (unlikely(!skb))
goto nomem;
}
opcode = *(u8 *)rsp;
if (c4iw_handlers[opcode]) {
c4iw_handlers[opcode](dev, skb);
} else {
pr_info("%s no handler opcode 0x%x...\n", __func__, opcode);
kfree_skb(skb);
}
return 0;
nomem:
return -1;
}
static int c4iw_uld_state_change(void *handle, enum cxgb4_state new_state)
{
struct uld_ctx *ctx = handle;
pr_debug("new_state %u\n", new_state);
switch (new_state) {
case CXGB4_STATE_UP:
pr_info("%s: Up\n", pci_name(ctx->lldi.pdev));
if (!ctx->dev) {
ctx->dev = c4iw_alloc(&ctx->lldi);
if (IS_ERR(ctx->dev)) {
pr_err("%s: initialization failed: %ld\n",
pci_name(ctx->lldi.pdev),
PTR_ERR(ctx->dev));
ctx->dev = NULL;
break;
}
INIT_WORK(&ctx->reg_work, c4iw_register_device);
queue_work(reg_workq, &ctx->reg_work);
}
break;
case CXGB4_STATE_DOWN:
pr_info("%s: Down\n", pci_name(ctx->lldi.pdev));
if (ctx->dev)
c4iw_remove(ctx);
break;
case CXGB4_STATE_FATAL_ERROR:
case CXGB4_STATE_START_RECOVERY:
pr_info("%s: Fatal Error\n", pci_name(ctx->lldi.pdev));
if (ctx->dev) {
struct ib_event event;
ctx->dev->rdev.flags |= T4_FATAL_ERROR;
memset(&event, 0, sizeof event);
event.event = IB_EVENT_DEVICE_FATAL;
event.device = &ctx->dev->ibdev;
ib_dispatch_event(&event);
c4iw_remove(ctx);
}
break;
case CXGB4_STATE_DETACH:
pr_info("%s: Detach\n", pci_name(ctx->lldi.pdev));
if (ctx->dev)
c4iw_remove(ctx);
break;
}
return 0;
}
static int disable_qp_db(int id, void *p, void *data)
{
struct c4iw_qp *qp = p;
t4_disable_wq_db(&qp->wq);
return 0;
}
static void stop_queues(struct uld_ctx *ctx)
{
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
unsigned long flags;
spin_lock_irqsave(&ctx->dev->lock, flags);
ctx->dev->rdev.stats.db_state_transitions++;
ctx->dev->db_state = STOPPED;
if (ctx->dev->rdev.flags & T4_STATUS_PAGE_DISABLED)
idr_for_each(&ctx->dev->qpidr, disable_qp_db, NULL);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
else
ctx->dev->rdev.status_page->db_off = 1;
spin_unlock_irqrestore(&ctx->dev->lock, flags);
}
static int enable_qp_db(int id, void *p, void *data)
{
struct c4iw_qp *qp = p;
t4_enable_wq_db(&qp->wq);
return 0;
}
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
static void resume_rc_qp(struct c4iw_qp *qp)
{
spin_lock(&qp->lock);
t4_ring_sq_db(&qp->wq, qp->wq.sq.wq_pidx_inc, NULL);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
qp->wq.sq.wq_pidx_inc = 0;
t4_ring_rq_db(&qp->wq, qp->wq.rq.wq_pidx_inc, NULL);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
qp->wq.rq.wq_pidx_inc = 0;
spin_unlock(&qp->lock);
}
static void resume_a_chunk(struct uld_ctx *ctx)
{
int i;
struct c4iw_qp *qp;
for (i = 0; i < DB_FC_RESUME_SIZE; i++) {
qp = list_first_entry(&ctx->dev->db_fc_list, struct c4iw_qp,
db_fc_entry);
list_del_init(&qp->db_fc_entry);
resume_rc_qp(qp);
if (list_empty(&ctx->dev->db_fc_list))
break;
}
}
static void resume_queues(struct uld_ctx *ctx)
{
spin_lock_irq(&ctx->dev->lock);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
if (ctx->dev->db_state != STOPPED)
goto out;
ctx->dev->db_state = FLOW_CONTROL;
while (1) {
if (list_empty(&ctx->dev->db_fc_list)) {
WARN_ON(ctx->dev->db_state != FLOW_CONTROL);
ctx->dev->db_state = NORMAL;
ctx->dev->rdev.stats.db_state_transitions++;
if (ctx->dev->rdev.flags & T4_STATUS_PAGE_DISABLED) {
idr_for_each(&ctx->dev->qpidr, enable_qp_db,
NULL);
} else {
ctx->dev->rdev.status_page->db_off = 0;
}
break;
} else {
if (cxgb4_dbfifo_count(ctx->dev->rdev.lldi.ports[0], 1)
< (ctx->dev->rdev.lldi.dbfifo_int_thresh <<
DB_FC_DRAIN_THRESH)) {
resume_a_chunk(ctx);
}
if (!list_empty(&ctx->dev->db_fc_list)) {
spin_unlock_irq(&ctx->dev->lock);
if (DB_FC_RESUME_DELAY) {
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(DB_FC_RESUME_DELAY);
}
spin_lock_irq(&ctx->dev->lock);
if (ctx->dev->db_state != FLOW_CONTROL)
break;
}
}
}
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
out:
if (ctx->dev->db_state != NORMAL)
ctx->dev->rdev.stats.db_fc_interruptions++;
spin_unlock_irq(&ctx->dev->lock);
}
struct qp_list {
unsigned idx;
struct c4iw_qp **qps;
};
static int add_and_ref_qp(int id, void *p, void *data)
{
struct qp_list *qp_listp = data;
struct c4iw_qp *qp = p;
c4iw_qp_add_ref(&qp->ibqp);
qp_listp->qps[qp_listp->idx++] = qp;
return 0;
}
static int count_qps(int id, void *p, void *data)
{
unsigned *countp = data;
(*countp)++;
return 0;
}
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
static void deref_qps(struct qp_list *qp_list)
{
int idx;
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
for (idx = 0; idx < qp_list->idx; idx++)
c4iw_qp_rem_ref(&qp_list->qps[idx]->ibqp);
}
static void recover_lost_dbs(struct uld_ctx *ctx, struct qp_list *qp_list)
{
int idx;
int ret;
for (idx = 0; idx < qp_list->idx; idx++) {
struct c4iw_qp *qp = qp_list->qps[idx];
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
spin_lock_irq(&qp->rhp->lock);
spin_lock(&qp->lock);
ret = cxgb4_sync_txq_pidx(qp->rhp->rdev.lldi.ports[0],
qp->wq.sq.qid,
t4_sq_host_wq_pidx(&qp->wq),
t4_sq_wq_size(&qp->wq));
if (ret) {
pr_err("%s: Fatal error - DB overflow recovery failed - error syncing SQ qid %u\n",
pci_name(ctx->lldi.pdev), qp->wq.sq.qid);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
spin_unlock(&qp->lock);
spin_unlock_irq(&qp->rhp->lock);
return;
}
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
qp->wq.sq.wq_pidx_inc = 0;
ret = cxgb4_sync_txq_pidx(qp->rhp->rdev.lldi.ports[0],
qp->wq.rq.qid,
t4_rq_host_wq_pidx(&qp->wq),
t4_rq_wq_size(&qp->wq));
if (ret) {
pr_err("%s: Fatal error - DB overflow recovery failed - error syncing RQ qid %u\n",
pci_name(ctx->lldi.pdev), qp->wq.rq.qid);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
spin_unlock(&qp->lock);
spin_unlock_irq(&qp->rhp->lock);
return;
}
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
qp->wq.rq.wq_pidx_inc = 0;
spin_unlock(&qp->lock);
spin_unlock_irq(&qp->rhp->lock);
/* Wait for the dbfifo to drain */
while (cxgb4_dbfifo_count(qp->rhp->rdev.lldi.ports[0], 1) > 0) {
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(usecs_to_jiffies(10));
}
}
}
static void recover_queues(struct uld_ctx *ctx)
{
int count = 0;
struct qp_list qp_list;
int ret;
/* slow everybody down */
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(usecs_to_jiffies(1000));
/* flush the SGE contexts */
ret = cxgb4_flush_eq_cache(ctx->dev->rdev.lldi.ports[0]);
if (ret) {
pr_err("%s: Fatal error - DB overflow recovery failed\n",
pci_name(ctx->lldi.pdev));
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
return;
}
/* Count active queues so we can build a list of queues to recover */
spin_lock_irq(&ctx->dev->lock);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
WARN_ON(ctx->dev->db_state != STOPPED);
ctx->dev->db_state = RECOVERY;
idr_for_each(&ctx->dev->qpidr, count_qps, &count);
treewide: kzalloc() -> kcalloc() The kzalloc() function has a 2-factor argument form, kcalloc(). This patch replaces cases of: kzalloc(a * b, gfp) with: kcalloc(a * b, gfp) as well as handling cases of: kzalloc(a * b * c, gfp) with: kzalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kzalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kzalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kzalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kzalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kzalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kzalloc( - sizeof(u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kzalloc( - sizeof(char) * COUNT + COUNT , ...) | kzalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kzalloc + kcalloc ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kzalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kzalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kzalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kzalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kzalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kzalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kzalloc(C1 * C2 * C3, ...) | kzalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kzalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kzalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kzalloc(sizeof(THING) * C2, ...) | kzalloc(sizeof(TYPE) * C2, ...) | kzalloc(C1 * C2 * C3, ...) | kzalloc(C1 * C2, ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kzalloc + kcalloc ( - (E1) * E2 + E1, E2 , ...) | - kzalloc + kcalloc ( - (E1) * (E2) + E1, E2 , ...) | - kzalloc + kcalloc ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12 21:03:40 +00:00
qp_list.qps = kcalloc(count, sizeof(*qp_list.qps), GFP_ATOMIC);
if (!qp_list.qps) {
spin_unlock_irq(&ctx->dev->lock);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
return;
}
qp_list.idx = 0;
/* add and ref each qp so it doesn't get freed */
idr_for_each(&ctx->dev->qpidr, add_and_ref_qp, &qp_list);
spin_unlock_irq(&ctx->dev->lock);
/* now traverse the list in a safe context to recover the db state*/
recover_lost_dbs(ctx, &qp_list);
/* we're almost done! deref the qps and clean up */
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
deref_qps(&qp_list);
kfree(qp_list.qps);
spin_lock_irq(&ctx->dev->lock);
cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes The current logic suffers from a slow response time to disable user DB usage, and also fails to avoid DB FIFO drops under heavy load. This commit fixes these deficiencies and makes the avoidance logic more optimal. This is done by more efficiently notifying the ULDs of potential DB problems, and implements a smoother flow control algorithm in iw_cxgb4, which is the ULD that puts the most load on the DB fifo. Design: cxgb4: Direct ULD callback from the DB FULL/DROP interrupt handler. This allows the ULD to stop doing user DB writes as quickly as possible. While user DB usage is disabled, the LLD will accumulate DB write events for its queues. Then once DB usage is reenabled, a single DB write is done for each queue with its accumulated write count. This reduces the load put on the DB fifo when reenabling. iw_cxgb4: Instead of marking each qp to indicate DB writes are disabled, we create a device-global status page that each user process maps. This allows iw_cxgb4 to only set this single bit to disable all DB writes for all user QPs vs traversing the idr of all the active QPs. If the libcxgb4 doesn't support this, then we fall back to the old approach of marking each QP. Thus we allow the new driver to work with an older libcxgb4. When the LLD upcalls iw_cxgb4 indicating DB FULL, we disable all DB writes via the status page and transition the DB state to STOPPED. As user processes see that DB writes are disabled, they call into iw_cxgb4 to submit their DB write events. Since the DB state is in STOPPED, the QP trying to write gets enqueued on a new DB "flow control" list. As subsequent DB writes are submitted for this flow controlled QP, the amount of writes are accumulated for each QP on the flow control list. So all the user QPs that are actively ringing the DB get put on this list and the number of writes they request are accumulated. When the LLD upcalls iw_cxgb4 indicating DB EMPTY, which is in a workq context, we change the DB state to FLOW_CONTROL, and begin resuming all the QPs that are on the flow control list. This logic runs on until the flow control list is empty or we exit FLOW_CONTROL mode (due to a DB DROP upcall, for example). QPs are removed from this list, and their accumulated DB write counts written to the DB FIFO. Sets of QPs, called chunks in the code, are removed at one time. The chunk size is 64. So 64 QPs are resumed at a time, and before the next chunk is resumed, the logic waits (blocks) for the DB FIFO to drain. This prevents resuming to quickly and overflowing the FIFO. Once the flow control list is empty, the db state transitions back to NORMAL and user QPs are again allowed to write directly to the user DB register. The algorithm is designed such that if the DB write load is high enough, then all the DB writes get submitted by the kernel using this flow controlled approach to avoid DB drops. As the load lightens though, we resume to normal DB writes directly by user applications. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-14 16:22:08 +00:00
WARN_ON(ctx->dev->db_state != RECOVERY);
ctx->dev->db_state = STOPPED;
spin_unlock_irq(&ctx->dev->lock);
}
static int c4iw_uld_control(void *handle, enum cxgb4_control control, ...)
{
struct uld_ctx *ctx = handle;
switch (control) {
case CXGB4_CONTROL_DB_FULL:
stop_queues(ctx);
ctx->dev->rdev.stats.db_full++;
break;
case CXGB4_CONTROL_DB_EMPTY:
resume_queues(ctx);
mutex_lock(&ctx->dev->rdev.stats.lock);
ctx->dev->rdev.stats.db_empty++;
mutex_unlock(&ctx->dev->rdev.stats.lock);
break;
case CXGB4_CONTROL_DB_DROP:
recover_queues(ctx);
mutex_lock(&ctx->dev->rdev.stats.lock);
ctx->dev->rdev.stats.db_drop++;
mutex_unlock(&ctx->dev->rdev.stats.lock);
break;
default:
pr_warn("%s: unknown control cmd %u\n",
pci_name(ctx->lldi.pdev), control);
break;
}
return 0;
}
static struct cxgb4_uld_info c4iw_uld_info = {
.name = DRV_NAME,
.nrxq = MAX_ULD_QSETS,
.ntxq = MAX_ULD_QSETS,
.rxq_size = 511,
.ciq = true,
.lro = false,
.add = c4iw_uld_add,
.rx_handler = c4iw_uld_rx_handler,
.state_change = c4iw_uld_state_change,
.control = c4iw_uld_control,
};
iw_cxgb4: add referencing to wait objects For messages sent from the host to fw that solicit a reply from fw, the c4iw_wr_wait struct pointer is passed in the host->fw message, and included in the fw->host fw6_msg reply. This allows the sender to wait until the reply is received, and the code processing the ingress reply to wake up the sender. If c4iw_wait_for_reply() times out, however, we need to keep the c4iw_wr_wait object around in case the reply eventually does arrive. Otherwise we have touch-after-free bugs in the wake_up paths. This was hit due to a bad kernel driver that blocked ingress processing of cxgb4 for a long time, causing iw_cxgb4 timeouts, but eventually resuming ingress processing and thus hitting the touch-after-free bug. So I want to fix iw_cxgb4 such that we'll at least keep the wait object around until the reply comes. If it never comes we leak a small amount of memory, but if it does come late, we won't potentially crash the system. So add a kref struct in the c4iw_wr_wait struct, and take a reference before sending a message to FW that will generate a FW6 reply. And remove the reference (and potentially free the wait object) when the reply is processed. The ep code also uses the wr_wait for non FW6 CPL messages and doesn't embed the c4iw_wr_wait object in the message sent to firmware. So for those cases we add c4iw_wake_up_noref(). The mr/mw, cq, and qp object create/destroy paths do need this reference logic. For these paths, c4iw_ref_send_wait() is introduced to take the wr_wait reference, send the msg to fw, and then wait for the reply. So going forward, iw_cxgb4 either uses c4iw_ofld_send(), c4iw_wait_for_reply() and c4iw_wake_up_noref() like is done in the some of the endpoint logic, or c4iw_ref_send_wait() and c4iw_wake_up_deref() (formerly c4iw_wake_up()) when sending messages with the c4iw_wr_wait object pointer embedded in the message and resulting FW6 reply. Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: Doug Ledford <dledford@redhat.com>
2017-09-26 20:13:17 +00:00
void _c4iw_free_wr_wait(struct kref *kref)
{
struct c4iw_wr_wait *wr_waitp;
wr_waitp = container_of(kref, struct c4iw_wr_wait, kref);
pr_debug("Free wr_wait %p\n", wr_waitp);
kfree(wr_waitp);
}
struct c4iw_wr_wait *c4iw_alloc_wr_wait(gfp_t gfp)
{
struct c4iw_wr_wait *wr_waitp;
wr_waitp = kzalloc(sizeof(*wr_waitp), gfp);
if (wr_waitp) {
kref_init(&wr_waitp->kref);
pr_debug("wr_wait %p\n", wr_waitp);
}
return wr_waitp;
}
static int __init c4iw_init_module(void)
{
int err;
err = c4iw_cm_init();
if (err)
return err;
c4iw_debugfs_root = debugfs_create_dir(DRV_NAME, NULL);
if (!c4iw_debugfs_root)
pr_warn("could not create debugfs entry, continuing\n");
reg_workq = create_singlethread_workqueue("Register_iWARP_device");
if (!reg_workq) {
pr_err("Failed creating workqueue to register iwarp device\n");
return -ENOMEM;
}
cxgb4_register_uld(CXGB4_ULD_RDMA, &c4iw_uld_info);
return 0;
}
static void __exit c4iw_exit_module(void)
{
struct uld_ctx *ctx, *tmp;
mutex_lock(&dev_mutex);
list_for_each_entry_safe(ctx, tmp, &uld_ctx_list, entry) {
if (ctx->dev)
c4iw_remove(ctx);
kfree(ctx);
}
mutex_unlock(&dev_mutex);
flush_workqueue(reg_workq);
destroy_workqueue(reg_workq);
cxgb4_unregister_uld(CXGB4_ULD_RDMA);
c4iw_cm_term();
debugfs_remove_recursive(c4iw_debugfs_root);
}
module_init(c4iw_init_module);
module_exit(c4iw_exit_module);