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Merge branch 'for-4.11/block' into for-4.11/rq-refactor

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Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Jens Axboe 2017-01-27 15:08:31 -07:00
commit f924ba70c1
38 changed files with 3102 additions and 679 deletions
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4
MAINTAINERS
View File

@ -8604,10 +8604,10 @@ S: Maintained
F: drivers/net/ethernet/netronome/
NETWORK BLOCK DEVICE (NBD)
M: Markus Pargmann <mpa@pengutronix.de>
M: Josef Bacik <jbacik@fb.com>
S: Maintained
L: linux-block@vger.kernel.org
L: nbd-general@lists.sourceforge.net
T: git git://git.pengutronix.de/git/mpa/linux-nbd.git
F: Documentation/blockdev/nbd.txt
F: drivers/block/nbd.c
F: include/uapi/linux/nbd.h

12
block/Kconfig
View File

@ -147,6 +147,18 @@ config BLK_WBT_MQ
Multiqueue currently doesn't have support for IO scheduling,
enabling this option is recommended.
config BLK_DEBUG_FS
bool "Block layer debugging information in debugfs"
default y
depends on DEBUG_FS
---help---
Include block layer debugging information in debugfs. This information
is mostly useful for kernel developers, but it doesn't incur any cost
at runtime.
Unless you are building a kernel for a tiny system, you should
say Y here.
menu "Partition Types"
source "block/partitions/Kconfig"

50
block/Kconfig.iosched
View File

@ -63,6 +63,56 @@ config DEFAULT_IOSCHED
default "cfq" if DEFAULT_CFQ
default "noop" if DEFAULT_NOOP
config MQ_IOSCHED_DEADLINE
tristate "MQ deadline I/O scheduler"
default y
---help---
MQ version of the deadline IO scheduler.
config MQ_IOSCHED_NONE
bool
default y
choice
prompt "Default single-queue blk-mq I/O scheduler"
default DEFAULT_SQ_NONE
help
Select the I/O scheduler which will be used by default for blk-mq
managed block devices with a single queue.
config DEFAULT_SQ_DEADLINE
bool "MQ Deadline" if MQ_IOSCHED_DEADLINE=y
config DEFAULT_SQ_NONE
bool "None"
endchoice
config DEFAULT_SQ_IOSCHED
string
default "mq-deadline" if DEFAULT_SQ_DEADLINE
default "none" if DEFAULT_SQ_NONE
choice
prompt "Default multi-queue blk-mq I/O scheduler"
default DEFAULT_MQ_NONE
help
Select the I/O scheduler which will be used by default for blk-mq
managed block devices with multiple queues.
config DEFAULT_MQ_DEADLINE
bool "MQ Deadline" if MQ_IOSCHED_DEADLINE=y
config DEFAULT_MQ_NONE
bool "None"
endchoice
config DEFAULT_MQ_IOSCHED
string
default "mq-deadline" if DEFAULT_MQ_DEADLINE
default "none" if DEFAULT_MQ_NONE
endmenu
endif

4
block/Makefile
View File

@ -6,7 +6,7 @@ obj-$(CONFIG_BLOCK) := bio.o elevator.o blk-core.o blk-tag.o blk-sysfs.o \
blk-flush.o blk-settings.o blk-ioc.o blk-map.o \
blk-exec.o blk-merge.o blk-softirq.o blk-timeout.o \
blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \
blk-mq-sysfs.o blk-mq-cpumap.o ioctl.o \
blk-mq-sysfs.o blk-mq-cpumap.o blk-mq-sched.o ioctl.o \
genhd.o scsi_ioctl.o partition-generic.o ioprio.o \
badblocks.o partitions/
@ -18,6 +18,7 @@ obj-$(CONFIG_BLK_DEV_THROTTLING) += blk-throttle.o
obj-$(CONFIG_IOSCHED_NOOP) += noop-iosched.o
obj-$(CONFIG_IOSCHED_DEADLINE) += deadline-iosched.o
obj-$(CONFIG_IOSCHED_CFQ) += cfq-iosched.o
obj-$(CONFIG_MQ_IOSCHED_DEADLINE) += mq-deadline.o
obj-$(CONFIG_BLOCK_COMPAT) += compat_ioctl.o
obj-$(CONFIG_BLK_CMDLINE_PARSER) += cmdline-parser.o
@ -25,3 +26,4 @@ obj-$(CONFIG_BLK_DEV_INTEGRITY) += bio-integrity.o blk-integrity.o t10-pi.o
obj-$(CONFIG_BLK_MQ_PCI) += blk-mq-pci.o
obj-$(CONFIG_BLK_DEV_ZONED) += blk-zoned.o
obj-$(CONFIG_BLK_WBT) += blk-wbt.o
obj-$(CONFIG_BLK_DEBUG_FS) += blk-mq-debugfs.o

22
block/blk-cgroup.c
View File

@ -1223,7 +1223,10 @@ int blkcg_activate_policy(struct request_queue *q,
if (blkcg_policy_enabled(q, pol))
return 0;
blk_queue_bypass_start(q);
if (q->mq_ops)
blk_mq_freeze_queue(q);
else
blk_queue_bypass_start(q);
pd_prealloc:
if (!pd_prealloc) {
pd_prealloc = pol->pd_alloc_fn(GFP_KERNEL, q->node);
@ -1261,7 +1264,10 @@ pd_prealloc:
spin_unlock_irq(q->queue_lock);
out_bypass_end:
blk_queue_bypass_end(q);
if (q->mq_ops)
blk_mq_unfreeze_queue(q);
else
blk_queue_bypass_end(q);
if (pd_prealloc)
pol->pd_free_fn(pd_prealloc);
return ret;
@ -1284,7 +1290,11 @@ void blkcg_deactivate_policy(struct request_queue *q,
if (!blkcg_policy_enabled(q, pol))
return;
blk_queue_bypass_start(q);
if (q->mq_ops)
blk_mq_freeze_queue(q);
else
blk_queue_bypass_start(q);
spin_lock_irq(q->queue_lock);
__clear_bit(pol->plid, q->blkcg_pols);
@ -1304,7 +1314,11 @@ void blkcg_deactivate_policy(struct request_queue *q,
}
spin_unlock_irq(q->queue_lock);
blk_queue_bypass_end(q);
if (q->mq_ops)
blk_mq_unfreeze_queue(q);
else
blk_queue_bypass_end(q);
}
EXPORT_SYMBOL_GPL(blkcg_deactivate_policy);

30
block/blk-core.c
View File

@ -39,6 +39,7 @@
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-sched.h"
#include "blk-wbt.h"
EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap);
@ -134,6 +135,7 @@ void blk_rq_init(struct request_queue *q, struct request *rq)
rq->cmd = rq->__cmd;
rq->cmd_len = BLK_MAX_CDB;
rq->tag = -1;
rq->internal_tag = -1;
rq->start_time = jiffies;
set_start_time_ns(rq);
rq->part = NULL;
@ -1033,28 +1035,12 @@ static bool blk_rq_should_init_elevator(struct bio *bio)
* Flush requests do not use the elevator so skip initialization.
* This allows a request to share the flush and elevator data.
*/
if (bio->bi_opf & (REQ_PREFLUSH | REQ_FUA))
if (op_is_flush(bio->bi_opf))
return false;
return true;
}
/**
* rq_ioc - determine io_context for request allocation
* @bio: request being allocated is for this bio (can be %NULL)
*
* Determine io_context to use for request allocation for @bio. May return
* %NULL if %current->io_context doesn't exist.
*/
static struct io_context *rq_ioc(struct bio *bio)
{
#ifdef CONFIG_BLK_CGROUP
if (bio && bio->bi_ioc)
return bio->bi_ioc;
#endif
return current->io_context;
}
/**
* __get_request - get a free request
* @rl: request list to allocate from
@ -1655,7 +1641,7 @@ static blk_qc_t blk_queue_bio(struct request_queue *q, struct bio *bio)
return BLK_QC_T_NONE;
}
if (bio->bi_opf & (REQ_PREFLUSH | REQ_FUA)) {
if (op_is_flush(bio->bi_opf)) {
spin_lock_irq(q->queue_lock);
where = ELEVATOR_INSERT_FLUSH;
goto get_rq;
@ -1894,7 +1880,7 @@ generic_make_request_checks(struct bio *bio)
* drivers without flush support don't have to worry
* about them.
*/
if ((bio->bi_opf & (REQ_PREFLUSH | REQ_FUA)) &&
if (op_is_flush(bio->bi_opf) &&
!test_bit(QUEUE_FLAG_WC, &q->queue_flags)) {
bio->bi_opf &= ~(REQ_PREFLUSH | REQ_FUA);
if (!nr_sectors) {
@ -2143,7 +2129,7 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq)
if (q->mq_ops) {
if (blk_queue_io_stat(q))
blk_account_io_start(rq, true);
blk_mq_insert_request(rq, false, true, false);
blk_mq_sched_insert_request(rq, false, true, false, false);
return 0;
}
@ -2159,7 +2145,7 @@ int blk_insert_cloned_request(struct request_queue *q, struct request *rq)
*/
BUG_ON(blk_queued_rq(rq));
if (rq->cmd_flags & (REQ_PREFLUSH | REQ_FUA))
if (op_is_flush(rq->cmd_flags))
where = ELEVATOR_INSERT_FLUSH;
add_acct_request(q, rq, where);
@ -3270,7 +3256,7 @@ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule)
/*
* rq is already accounted, so use raw insert
*/
if (rq->cmd_flags & (REQ_PREFLUSH | REQ_FUA))
if (op_is_flush(rq->cmd_flags))
__elv_add_request(q, rq, ELEVATOR_INSERT_FLUSH);
else
__elv_add_request(q, rq, ELEVATOR_INSERT_SORT_MERGE);

3
block/blk-exec.c
View File

@ -9,6 +9,7 @@
#include <linux/sched/sysctl.h>
#include "blk.h"
#include "blk-mq-sched.h"
/*
* for max sense size
@ -65,7 +66,7 @@ void blk_execute_rq_nowait(struct request_queue *q, struct gendisk *bd_disk,
* be reused after dying flag is set
*/
if (q->mq_ops) {
blk_mq_insert_request(rq, at_head, true, false);
blk_mq_sched_insert_request(rq, at_head, true, false, false);
return;
}

12
block/blk-flush.c
View File

@ -74,6 +74,7 @@
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-tag.h"
#include "blk-mq-sched.h"
/* FLUSH/FUA sequences */
enum {
@ -391,9 +392,10 @@ static void mq_flush_data_end_io(struct request *rq, int error)
* the comment in flush_end_io().
*/
spin_lock_irqsave(&fq->mq_flush_lock, flags);
if (blk_flush_complete_seq(rq, fq, REQ_FSEQ_DATA, error))
blk_mq_run_hw_queue(hctx, true);
blk_flush_complete_seq(rq, fq, REQ_FSEQ_DATA, error);
spin_unlock_irqrestore(&fq->mq_flush_lock, flags);
blk_mq_run_hw_queue(hctx, true);
}
/**
@ -453,9 +455,9 @@ void blk_insert_flush(struct request *rq)
*/
if ((policy & REQ_FSEQ_DATA) &&
!(policy & (REQ_FSEQ_PREFLUSH | REQ_FSEQ_POSTFLUSH))) {
if (q->mq_ops) {
blk_mq_insert_request(rq, false, true, false);
} else
if (q->mq_ops)
blk_mq_sched_insert_request(rq, false, true, false, false);
else
list_add_tail(&rq->queuelist, &q->queue_head);
return;
}

12
block/blk-ioc.c
View File

@ -43,8 +43,10 @@ static void ioc_exit_icq(struct io_cq *icq)
if (icq->flags & ICQ_EXITED)
return;
if (et->ops.elevator_exit_icq_fn)
et->ops.elevator_exit_icq_fn(icq);
if (et->uses_mq && et->ops.mq.exit_icq)
et->ops.mq.exit_icq(icq);
else if (!et->uses_mq && et->ops.sq.elevator_exit_icq_fn)
et->ops.sq.elevator_exit_icq_fn(icq);
icq->flags |= ICQ_EXITED;
}
@ -383,8 +385,10 @@ struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q,
if (likely(!radix_tree_insert(&ioc->icq_tree, q->id, icq))) {
hlist_add_head(&icq->ioc_node, &ioc->icq_list);
list_add(&icq->q_node, &q->icq_list);
if (et->ops.elevator_init_icq_fn)
et->ops.elevator_init_icq_fn(icq);
if (et->uses_mq && et->ops.mq.init_icq)
et->ops.mq.init_icq(icq);
else if (!et->uses_mq && et->ops.sq.elevator_init_icq_fn)
et->ops.sq.elevator_init_icq_fn(icq);
} else {
kmem_cache_free(et->icq_cache, icq);
icq = ioc_lookup_icq(ioc, q);

4
block/blk-merge.c
View File

@ -763,8 +763,8 @@ int blk_attempt_req_merge(struct request_queue *q, struct request *rq,
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_allow_rq_merge_fn)
if (!e->type->ops.elevator_allow_rq_merge_fn(q, rq, next))
if (!e->uses_mq && e->type->ops.sq.elevator_allow_rq_merge_fn)
if (!e->type->ops.sq.elevator_allow_rq_merge_fn(q, rq, next))
return 0;
return attempt_merge(q, rq, next);

756
block/blk-mq-debugfs.c Normal file
View File

@ -0,0 +1,756 @@
/*
* Copyright (C) 2017 Facebook
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <linux/kernel.h>
#include <linux/blkdev.h>
#include <linux/debugfs.h>
#include <linux/blk-mq.h>
#include "blk-mq.h"
#include "blk-mq-tag.h"
struct blk_mq_debugfs_attr {
const char *name;
umode_t mode;
const struct file_operations *fops;
};
static struct dentry *block_debugfs_root;
static int blk_mq_debugfs_seq_open(struct inode *inode, struct file *file,
const struct seq_operations *ops)
{
struct seq_file *m;
int ret;
ret = seq_open(file, ops);
if (!ret) {
m = file->private_data;
m->private = inode->i_private;
}
return ret;
}
static int hctx_state_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "0x%lx\n", hctx->state);
return 0;
}
static int hctx_state_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_state_show, inode->i_private);
}
static const struct file_operations hctx_state_fops = {
.open = hctx_state_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_flags_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "0x%lx\n", hctx->flags);
return 0;
}
static int hctx_flags_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_flags_show, inode->i_private);
}
static const struct file_operations hctx_flags_fops = {
.open = hctx_flags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int blk_mq_debugfs_rq_show(struct seq_file *m, void *v)
{
struct request *rq = list_entry_rq(v);
seq_printf(m, "%p {.cmd_type=%u, .cmd_flags=0x%x, .rq_flags=0x%x, .tag=%d, .internal_tag=%d}\n",
rq, rq->cmd_type, rq->cmd_flags, (unsigned int)rq->rq_flags,
rq->tag, rq->internal_tag);
return 0;
}
static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos)
{
struct blk_mq_hw_ctx *hctx = m->private;
spin_lock(&hctx->lock);
return seq_list_start(&hctx->dispatch, *pos);
}
static void *hctx_dispatch_next(struct seq_file *m, void *v, loff_t *pos)
{
struct blk_mq_hw_ctx *hctx = m->private;
return seq_list_next(v, &hctx->dispatch, pos);
}
static void hctx_dispatch_stop(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
spin_unlock(&hctx->lock);
}
static const struct seq_operations hctx_dispatch_seq_ops = {
.start = hctx_dispatch_start,
.next = hctx_dispatch_next,
.stop = hctx_dispatch_stop,
.show = blk_mq_debugfs_rq_show,
};
static int hctx_dispatch_open(struct inode *inode, struct file *file)
{
return blk_mq_debugfs_seq_open(inode, file, &hctx_dispatch_seq_ops);
}
static const struct file_operations hctx_dispatch_fops = {
.open = hctx_dispatch_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int hctx_ctx_map_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
sbitmap_bitmap_show(&hctx->ctx_map, m);
return 0;
}
static int hctx_ctx_map_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_ctx_map_show, inode->i_private);
}
static const struct file_operations hctx_ctx_map_fops = {
.open = hctx_ctx_map_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void blk_mq_debugfs_tags_show(struct seq_file *m,
struct blk_mq_tags *tags)
{
seq_printf(m, "nr_tags=%u\n", tags->nr_tags);
seq_printf(m, "nr_reserved_tags=%u\n", tags->nr_reserved_tags);
seq_printf(m, "active_queues=%d\n",
atomic_read(&tags->active_queues));
seq_puts(m, "\nbitmap_tags:\n");
sbitmap_queue_show(&tags->bitmap_tags, m);
if (tags->nr_reserved_tags) {
seq_puts(m, "\nbreserved_tags:\n");
sbitmap_queue_show(&tags->breserved_tags, m);
}
}
static int hctx_tags_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct request_queue *q = hctx->queue;
mutex_lock(&q->sysfs_lock);
if (hctx->tags)
blk_mq_debugfs_tags_show(m, hctx->tags);
mutex_unlock(&q->sysfs_lock);
return 0;
}
static int hctx_tags_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_tags_show, inode->i_private);
}
static const struct file_operations hctx_tags_fops = {
.open = hctx_tags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_tags_bitmap_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct request_queue *q = hctx->queue;
mutex_lock(&q->sysfs_lock);
if (hctx->tags)
sbitmap_bitmap_show(&hctx->tags->bitmap_tags.sb, m);
mutex_unlock(&q->sysfs_lock);
return 0;
}
static int hctx_tags_bitmap_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_tags_bitmap_show, inode->i_private);
}
static const struct file_operations hctx_tags_bitmap_fops = {
.open = hctx_tags_bitmap_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_sched_tags_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct request_queue *q = hctx->queue;
mutex_lock(&q->sysfs_lock);
if (hctx->sched_tags)
blk_mq_debugfs_tags_show(m, hctx->sched_tags);
mutex_unlock(&q->sysfs_lock);
return 0;
}
static int hctx_sched_tags_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_sched_tags_show, inode->i_private);
}
static const struct file_operations hctx_sched_tags_fops = {
.open = hctx_sched_tags_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_sched_tags_bitmap_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct request_queue *q = hctx->queue;
mutex_lock(&q->sysfs_lock);
if (hctx->sched_tags)
sbitmap_bitmap_show(&hctx->sched_tags->bitmap_tags.sb, m);
mutex_unlock(&q->sysfs_lock);
return 0;
}
static int hctx_sched_tags_bitmap_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_sched_tags_bitmap_show, inode->i_private);
}
static const struct file_operations hctx_sched_tags_bitmap_fops = {
.open = hctx_sched_tags_bitmap_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_io_poll_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "considered=%lu\n", hctx->poll_considered);
seq_printf(m, "invoked=%lu\n", hctx->poll_invoked);
seq_printf(m, "success=%lu\n", hctx->poll_success);
return 0;
}
static int hctx_io_poll_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_io_poll_show, inode->i_private);
}
static ssize_t hctx_io_poll_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_hw_ctx *hctx = m->private;
hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
return count;
}
static const struct file_operations hctx_io_poll_fops = {
.open = hctx_io_poll_open,
.read = seq_read,
.write = hctx_io_poll_write,
.llseek = seq_lseek,
.release = single_release,
};
static void print_stat(struct seq_file *m, struct blk_rq_stat *stat)
{
seq_printf(m, "samples=%d, mean=%lld, min=%llu, max=%llu",
stat->nr_samples, stat->mean, stat->min, stat->max);
}
static int hctx_stats_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
struct blk_rq_stat stat[2];
blk_stat_init(&stat[BLK_STAT_READ]);
blk_stat_init(&stat[BLK_STAT_WRITE]);
blk_hctx_stat_get(hctx, stat);
seq_puts(m, "read: ");
print_stat(m, &stat[BLK_STAT_READ]);
seq_puts(m, "\n");
seq_puts(m, "write: ");
print_stat(m, &stat[BLK_STAT_WRITE]);
seq_puts(m, "\n");
return 0;
}
static int hctx_stats_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_stats_show, inode->i_private);
}
static ssize_t hctx_stats_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_hw_ctx *hctx = m->private;
struct blk_mq_ctx *ctx;
int i;
hctx_for_each_ctx(hctx, ctx, i) {
blk_stat_init(&ctx->stat[BLK_STAT_READ]);
blk_stat_init(&ctx->stat[BLK_STAT_WRITE]);
}
return count;
}
static const struct file_operations hctx_stats_fops = {
.open = hctx_stats_open,
.read = seq_read,
.write = hctx_stats_write,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_dispatched_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
int i;
seq_printf(m, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
unsigned int d = 1U << (i - 1);
seq_printf(m, "%8u\t%lu\n", d, hctx->dispatched[i]);
}
seq_printf(m, "%8u+\t%lu\n", 1U << (i - 1), hctx->dispatched[i]);
return 0;
}
static int hctx_dispatched_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_dispatched_show, inode->i_private);
}
static ssize_t hctx_dispatched_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_hw_ctx *hctx = m->private;
int i;
for (i = 0; i < BLK_MQ_MAX_DISPATCH_ORDER; i++)
hctx->dispatched[i] = 0;
return count;
}
static const struct file_operations hctx_dispatched_fops = {
.open = hctx_dispatched_open,
.read = seq_read,
.write = hctx_dispatched_write,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_queued_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "%lu\n", hctx->queued);
return 0;
}
static int hctx_queued_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_queued_show, inode->i_private);
}
static ssize_t hctx_queued_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_hw_ctx *hctx = m->private;
hctx->queued = 0;
return count;
}
static const struct file_operations hctx_queued_fops = {
.open = hctx_queued_open,
.read = seq_read,
.write = hctx_queued_write,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_run_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "%lu\n", hctx->run);
return 0;
}
static int hctx_run_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_run_show, inode->i_private);
}
static ssize_t hctx_run_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_hw_ctx *hctx = m->private;
hctx->run = 0;
return count;
}
static const struct file_operations hctx_run_fops = {
.open = hctx_run_open,
.read = seq_read,
.write = hctx_run_write,
.llseek = seq_lseek,
.release = single_release,
};
static int hctx_active_show(struct seq_file *m, void *v)
{
struct blk_mq_hw_ctx *hctx = m->private;
seq_printf(m, "%d\n", atomic_read(&hctx->nr_active));
return 0;
}
static int hctx_active_open(struct inode *inode, struct file *file)
{
return single_open(file, hctx_active_show, inode->i_private);
}
static const struct file_operations hctx_active_fops = {
.open = hctx_active_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static void *ctx_rq_list_start(struct seq_file *m, loff_t *pos)
{
struct blk_mq_ctx *ctx = m->private;
spin_lock(&ctx->lock);
return seq_list_start(&ctx->rq_list, *pos);
}
static void *ctx_rq_list_next(struct seq_file *m, void *v, loff_t *pos)
{
struct blk_mq_ctx *ctx = m->private;
return seq_list_next(v, &ctx->rq_list, pos);
}
static void ctx_rq_list_stop(struct seq_file *m, void *v)
{
struct blk_mq_ctx *ctx = m->private;
spin_unlock(&ctx->lock);
}
static const struct seq_operations ctx_rq_list_seq_ops = {
.start = ctx_rq_list_start,
.next = ctx_rq_list_next,
.stop = ctx_rq_list_stop,
.show = blk_mq_debugfs_rq_show,
};
static int ctx_rq_list_open(struct inode *inode, struct file *file)
{
return blk_mq_debugfs_seq_open(inode, file, &ctx_rq_list_seq_ops);
}
static const struct file_operations ctx_rq_list_fops = {
.open = ctx_rq_list_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
static int ctx_dispatched_show(struct seq_file *m, void *v)
{
struct blk_mq_ctx *ctx = m->private;
seq_printf(m, "%lu %lu\n", ctx->rq_dispatched[1], ctx->rq_dispatched[0]);
return 0;
}
static int ctx_dispatched_open(struct inode *inode, struct file *file)
{
return single_open(file, ctx_dispatched_show, inode->i_private);
}
static ssize_t ctx_dispatched_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_ctx *ctx = m->private;
ctx->rq_dispatched[0] = ctx->rq_dispatched[1] = 0;
return count;
}
static const struct file_operations ctx_dispatched_fops = {
.open = ctx_dispatched_open,
.read = seq_read,
.write = ctx_dispatched_write,
.llseek = seq_lseek,
.release = single_release,
};
static int ctx_merged_show(struct seq_file *m, void *v)
{
struct blk_mq_ctx *ctx = m->private;
seq_printf(m, "%lu\n", ctx->rq_merged);
return 0;
}
static int ctx_merged_open(struct inode *inode, struct file *file)
{
return single_open(file, ctx_merged_show, inode->i_private);
}
static ssize_t ctx_merged_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_ctx *ctx = m->private;
ctx->rq_merged = 0;
return count;
}
static const struct file_operations ctx_merged_fops = {
.open = ctx_merged_open,
.read = seq_read,
.write = ctx_merged_write,
.llseek = seq_lseek,
.release = single_release,
};
static int ctx_completed_show(struct seq_file *m, void *v)
{
struct blk_mq_ctx *ctx = m->private;
seq_printf(m, "%lu %lu\n", ctx->rq_completed[1], ctx->rq_completed[0]);
return 0;
}
static int ctx_completed_open(struct inode *inode, struct file *file)
{
return single_open(file, ctx_completed_show, inode->i_private);
}
static ssize_t ctx_completed_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
struct blk_mq_ctx *ctx = m->private;
ctx->rq_completed[0] = ctx->rq_completed[1] = 0;
return count;
}
static const struct file_operations ctx_completed_fops = {
.open = ctx_completed_open,
.read = seq_read,
.write = ctx_completed_write,
.llseek = seq_lseek,
.release = single_release,
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
{"state", 0400, &hctx_state_fops},
{"flags", 0400, &hctx_flags_fops},
{"dispatch", 0400, &hctx_dispatch_fops},
{"ctx_map", 0400, &hctx_ctx_map_fops},
{"tags", 0400, &hctx_tags_fops},
{"tags_bitmap", 0400, &hctx_tags_bitmap_fops},
{"sched_tags", 0400, &hctx_sched_tags_fops},
{"sched_tags_bitmap", 0400, &hctx_sched_tags_bitmap_fops},
{"io_poll", 0600, &hctx_io_poll_fops},
{"stats", 0600, &hctx_stats_fops},
{"dispatched", 0600, &hctx_dispatched_fops},
{"queued", 0600, &hctx_queued_fops},
{"run", 0600, &hctx_run_fops},
{"active", 0400, &hctx_active_fops},
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
{"rq_list", 0400, &ctx_rq_list_fops},
{"dispatched", 0600, &ctx_dispatched_fops},
{"merged", 0600, &ctx_merged_fops},
{"completed", 0600, &ctx_completed_fops},
};
int blk_mq_debugfs_register(struct request_queue *q, const char *name)
{
if (!block_debugfs_root)
return -ENOENT;
q->debugfs_dir = debugfs_create_dir(name, block_debugfs_root);
if (!q->debugfs_dir)
goto err;
if (blk_mq_debugfs_register_hctxs(q))
goto err;
return 0;
err:
blk_mq_debugfs_unregister(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister(struct request_queue *q)
{
debugfs_remove_recursive(q->debugfs_dir);
q->mq_debugfs_dir = NULL;
q->debugfs_dir = NULL;
}
static int blk_mq_debugfs_register_ctx(struct request_queue *q,
struct blk_mq_ctx *ctx,
struct dentry *hctx_dir)
{
struct dentry *ctx_dir;
char name[20];
int i;
snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
ctx_dir = debugfs_create_dir(name, hctx_dir);
if (!ctx_dir)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(blk_mq_debugfs_ctx_attrs); i++) {
const struct blk_mq_debugfs_attr *attr;
attr = &blk_mq_debugfs_ctx_attrs[i];
if (!debugfs_create_file(attr->name, attr->mode, ctx_dir, ctx,
attr->fops))
return -ENOMEM;
}
return 0;
}
static int blk_mq_debugfs_register_hctx(struct request_queue *q,
struct blk_mq_hw_ctx *hctx)
{
struct blk_mq_ctx *ctx;
struct dentry *hctx_dir;
char name[20];
int i;
snprintf(name, sizeof(name), "%u", hctx->queue_num);
hctx_dir = debugfs_create_dir(name, q->mq_debugfs_dir);
if (!hctx_dir)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(blk_mq_debugfs_hctx_attrs); i++) {
const struct blk_mq_debugfs_attr *attr;
attr = &blk_mq_debugfs_hctx_attrs[i];
if (!debugfs_create_file(attr->name, attr->mode, hctx_dir, hctx,
attr->fops))
return -ENOMEM;
}
hctx_for_each_ctx(hctx, ctx, i) {
if (blk_mq_debugfs_register_ctx(q, ctx, hctx_dir))
return -ENOMEM;
}
return 0;
}
int blk_mq_debugfs_register_hctxs(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
if (!q->debugfs_dir)
return -ENOENT;
q->mq_debugfs_dir = debugfs_create_dir("mq", q->debugfs_dir);
if (!q->mq_debugfs_dir)
goto err;
queue_for_each_hw_ctx(q, hctx, i) {
if (blk_mq_debugfs_register_hctx(q, hctx))
goto err;
}
return 0;
err:
blk_mq_debugfs_unregister_hctxs(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
{
debugfs_remove_recursive(q->mq_debugfs_dir);
q->mq_debugfs_dir = NULL;
}
void blk_mq_debugfs_init(void)
{
block_debugfs_root = debugfs_create_dir("block", NULL);
}

481
block/blk-mq-sched.c Normal file
View File

@ -0,0 +1,481 @@
/*
* blk-mq scheduling framework
*
* Copyright (C) 2016 Jens Axboe
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/blk-mq.h>
#include <trace/events/block.h>
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-sched.h"
#include "blk-mq-tag.h"
#include "blk-wbt.h"
void blk_mq_sched_free_hctx_data(struct request_queue *q,
void (*exit)(struct blk_mq_hw_ctx *))
{
struct blk_mq_hw_ctx *hctx;
int i;
queue_for_each_hw_ctx(q, hctx, i) {
if (exit && hctx->sched_data)
exit(hctx);
kfree(hctx->sched_data);
hctx->sched_data = NULL;
}
}
EXPORT_SYMBOL_GPL(blk_mq_sched_free_hctx_data);
int blk_mq_sched_init_hctx_data(struct request_queue *q, size_t size,
int (*init)(struct blk_mq_hw_ctx *),
void (*exit)(struct blk_mq_hw_ctx *))
{
struct blk_mq_hw_ctx *hctx;
int ret;
int i;
queue_for_each_hw_ctx(q, hctx, i) {
hctx->sched_data = kmalloc_node(size, GFP_KERNEL, hctx->numa_node);
if (!hctx->sched_data) {
ret = -ENOMEM;
goto error;
}
if (init) {
ret = init(hctx);
if (ret) {
/*
* We don't want to give exit() a partially
* initialized sched_data. init() must clean up
* if it fails.
*/
kfree(hctx->sched_data);
hctx->sched_data = NULL;
goto error;
}
}
}
return 0;
error:
blk_mq_sched_free_hctx_data(q, exit);
return ret;
}
EXPORT_SYMBOL_GPL(blk_mq_sched_init_hctx_data);
static void __blk_mq_sched_assign_ioc(struct request_queue *q,
struct request *rq, struct io_context *ioc)
{
struct io_cq *icq;
spin_lock_irq(q->queue_lock);
icq = ioc_lookup_icq(ioc, q);
spin_unlock_irq(q->queue_lock);
if (!icq) {
icq = ioc_create_icq(ioc, q, GFP_ATOMIC);
if (!icq)
return;
}
rq->elv.icq = icq;
if (!blk_mq_sched_get_rq_priv(q, rq)) {
rq->rq_flags |= RQF_ELVPRIV;
get_io_context(icq->ioc);
return;
}
rq->elv.icq = NULL;
}
static void blk_mq_sched_assign_ioc(struct request_queue *q,
struct request *rq, struct bio *bio)
{
struct io_context *ioc;
ioc = rq_ioc(bio);
if (ioc)
__blk_mq_sched_assign_ioc(q, rq, ioc);
}
struct request *blk_mq_sched_get_request(struct request_queue *q,
struct bio *bio,
unsigned int op,
struct blk_mq_alloc_data *data)
{
struct elevator_queue *e = q->elevator;
struct blk_mq_hw_ctx *hctx;
struct blk_mq_ctx *ctx;
struct request *rq;
blk_queue_enter_live(q);
ctx = blk_mq_get_ctx(q);
hctx = blk_mq_map_queue(q, ctx->cpu);
blk_mq_set_alloc_data(data, q, data->flags, ctx, hctx);
if (e) {
data->flags |= BLK_MQ_REQ_INTERNAL;
/*
* Flush requests are special and go directly to the
* dispatch list.
*/
if (!op_is_flush(op) && e->type->ops.mq.get_request) {
rq = e->type->ops.mq.get_request(q, op, data);
if (rq)
rq->rq_flags |= RQF_QUEUED;
} else
rq = __blk_mq_alloc_request(data, op);
} else {
rq = __blk_mq_alloc_request(data, op);
if (rq)
data->hctx->tags->rqs[rq->tag] = rq;
}
if (rq) {
if (!op_is_flush(op)) {
rq->elv.icq = NULL;
if (e && e->type->icq_cache)
blk_mq_sched_assign_ioc(q, rq, bio);
}
data->hctx->queued++;
return rq;
}
blk_queue_exit(q);
return NULL;
}
void blk_mq_sched_put_request(struct request *rq)
{
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
if (rq->rq_flags & RQF_ELVPRIV) {
blk_mq_sched_put_rq_priv(rq->q, rq);
if (rq->elv.icq) {
put_io_context(rq->elv.icq->ioc);
rq->elv.icq = NULL;
}
}
if ((rq->rq_flags & RQF_QUEUED) && e && e->type->ops.mq.put_request)
e->type->ops.mq.put_request(rq);
else
blk_mq_finish_request(rq);
}
void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx)
{
struct elevator_queue *e = hctx->queue->elevator;
LIST_HEAD(rq_list);
if (unlikely(blk_mq_hctx_stopped(hctx)))
return;
hctx->run++;
/*
* If we have previous entries on our dispatch list, grab them first for
* more fair dispatch.
*/
if (!list_empty_careful(&hctx->dispatch)) {
spin_lock(&hctx->lock);
if (!list_empty(&hctx->dispatch))
list_splice_init(&hctx->dispatch, &rq_list);
spin_unlock(&hctx->lock);
}
/*
* Only ask the scheduler for requests, if we didn't have residual
* requests from the dispatch list. This is to avoid the case where
* we only ever dispatch a fraction of the requests available because
* of low device queue depth. Once we pull requests out of the IO
* scheduler, we can no longer merge or sort them. So it's best to
* leave them there for as long as we can. Mark the hw queue as
* needing a restart in that case.
*/
if (!list_empty(&rq_list)) {
blk_mq_sched_mark_restart(hctx);
blk_mq_dispatch_rq_list(hctx, &rq_list);
} else if (!e || !e->type->ops.mq.dispatch_request) {
blk_mq_flush_busy_ctxs(hctx, &rq_list);
blk_mq_dispatch_rq_list(hctx, &rq_list);
} else {
do {
struct request *rq;
rq = e->type->ops.mq.dispatch_request(hctx);
if (!rq)
break;
list_add(&rq->queuelist, &rq_list);
} while (blk_mq_dispatch_rq_list(hctx, &rq_list));
}
}
void blk_mq_sched_move_to_dispatch(struct blk_mq_hw_ctx *hctx,
struct list_head *rq_list,
struct request *(*get_rq)(struct blk_mq_hw_ctx *))
{
do {
struct request *rq;
rq = get_rq(hctx);
if (!rq)
break;
list_add_tail(&rq->queuelist, rq_list);
} while (1);
}
EXPORT_SYMBOL_GPL(blk_mq_sched_move_to_dispatch);
bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio)
{
struct request *rq;
int ret;
ret = elv_merge(q, &rq, bio);
if (ret == ELEVATOR_BACK_MERGE) {
if (!blk_mq_sched_allow_merge(q, rq, bio))
return false;
if (bio_attempt_back_merge(q, rq, bio)) {
if (!attempt_back_merge(q, rq))
elv_merged_request(q, rq, ret);
return true;
}
} else if (ret == ELEVATOR_FRONT_MERGE) {
if (!blk_mq_sched_allow_merge(q, rq, bio))
return false;
if (bio_attempt_front_merge(q, rq, bio)) {
if (!attempt_front_merge(q, rq))
elv_merged_request(q, rq, ret);
return true;
}
}
return false;
}
EXPORT_SYMBOL_GPL(blk_mq_sched_try_merge);
bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.mq.bio_merge) {
struct blk_mq_ctx *ctx = blk_mq_get_ctx(q);
struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
blk_mq_put_ctx(ctx);
return e->type->ops.mq.bio_merge(hctx, bio);
}
return false;
}
bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq)
{
return rq_mergeable(rq) && elv_attempt_insert_merge(q, rq);
}
EXPORT_SYMBOL_GPL(blk_mq_sched_try_insert_merge);
void blk_mq_sched_request_inserted(struct request *rq)
{
trace_block_rq_insert(rq->q, rq);
}
EXPORT_SYMBOL_GPL(blk_mq_sched_request_inserted);
bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx, struct request *rq)
{
if (rq->tag == -1) {
rq->rq_flags |= RQF_SORTED;
return false;
}
/*
* If we already have a real request tag, send directly to
* the dispatch list.
*/
spin_lock(&hctx->lock);
list_add(&rq->queuelist, &hctx->dispatch);
spin_unlock(&hctx->lock);
return true;
}
EXPORT_SYMBOL_GPL(blk_mq_sched_bypass_insert);
static void blk_mq_sched_restart_hctx(struct blk_mq_hw_ctx *hctx)
{
if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) {
clear_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
if (blk_mq_hctx_has_pending(hctx))
blk_mq_run_hw_queue(hctx, true);
}
}
void blk_mq_sched_restart_queues(struct blk_mq_hw_ctx *hctx)
{
unsigned int i;
if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
blk_mq_sched_restart_hctx(hctx);
else {
struct request_queue *q = hctx->queue;
if (!test_bit(QUEUE_FLAG_RESTART, &q->queue_flags))
return;
clear_bit(QUEUE_FLAG_RESTART, &q->queue_flags);
queue_for_each_hw_ctx(q, hctx, i)
blk_mq_sched_restart_hctx(hctx);
}
}
/*
* Add flush/fua to the queue. If we fail getting a driver tag, then
* punt to the requeue list. Requeue will re-invoke us from a context
* that's safe to block from.
*/
static void blk_mq_sched_insert_flush(struct blk_mq_hw_ctx *hctx,
struct request *rq, bool can_block)
{
if (blk_mq_get_driver_tag(rq, &hctx, can_block)) {
blk_insert_flush(rq);
blk_mq_run_hw_queue(hctx, true);
} else
blk_mq_add_to_requeue_list(rq, true, true);
}
void blk_mq_sched_insert_request(struct request *rq, bool at_head,
bool run_queue, bool async, bool can_block)
{
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
struct blk_mq_ctx *ctx = rq->mq_ctx;
struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
if (rq->tag == -1 && op_is_flush(rq->cmd_flags)) {
blk_mq_sched_insert_flush(hctx, rq, can_block);
return;
}
if (e && e->type->ops.mq.insert_requests) {
LIST_HEAD(list);
list_add(&rq->queuelist, &list);
e->type->ops.mq.insert_requests(hctx, &list, at_head);
} else {
spin_lock(&ctx->lock);
__blk_mq_insert_request(hctx, rq, at_head);
spin_unlock(&ctx->lock);
}
if (run_queue)
blk_mq_run_hw_queue(hctx, async);
}
void blk_mq_sched_insert_requests(struct request_queue *q,
struct blk_mq_ctx *ctx,
struct list_head *list, bool run_queue_async)
{
struct blk_mq_hw_ctx *hctx = blk_mq_map_queue(q, ctx->cpu);
struct elevator_queue *e = hctx->queue->elevator;
if (e && e->type->ops.mq.insert_requests)
e->type->ops.mq.insert_requests(hctx, list, false);
else
blk_mq_insert_requests(hctx, ctx, list);
blk_mq_run_hw_queue(hctx, run_queue_async);
}
static void blk_mq_sched_free_tags(struct blk_mq_tag_set *set,
struct blk_mq_hw_ctx *hctx,
unsigned int hctx_idx)
{
if (hctx->sched_tags) {
blk_mq_free_rqs(set, hctx->sched_tags, hctx_idx);
blk_mq_free_rq_map(hctx->sched_tags);
hctx->sched_tags = NULL;
}
}
int blk_mq_sched_setup(struct request_queue *q)
{
struct blk_mq_tag_set *set = q->tag_set;
struct blk_mq_hw_ctx *hctx;
int ret, i;
/*
* Default to 256, since we don't split into sync/async like the
* old code did. Additionally, this is a per-hw queue depth.
*/
q->nr_requests = 2 * BLKDEV_MAX_RQ;
/*
* We're switching to using an IO scheduler, so setup the hctx
* scheduler tags and switch the request map from the regular
* tags to scheduler tags. First allocate what we need, so we
* can safely fail and fallback, if needed.
*/
ret = 0;
queue_for_each_hw_ctx(q, hctx, i) {
hctx->sched_tags = blk_mq_alloc_rq_map(set, i, q->nr_requests, 0);
if (!hctx->sched_tags) {
ret = -ENOMEM;
break;
}
ret = blk_mq_alloc_rqs(set, hctx->sched_tags, i, q->nr_requests);
if (ret)
break;
}
/*
* If we failed, free what we did allocate
*/
if (ret) {
queue_for_each_hw_ctx(q, hctx, i) {
if (!hctx->sched_tags)
continue;
blk_mq_sched_free_tags(set, hctx, i);
}
return ret;
}
return 0;
}
void blk_mq_sched_teardown(struct request_queue *q)
{
struct blk_mq_tag_set *set = q->tag_set;
struct blk_mq_hw_ctx *hctx;
int i;
queue_for_each_hw_ctx(q, hctx, i)
blk_mq_sched_free_tags(set, hctx, i);
}
int blk_mq_sched_init(struct request_queue *q)
{
int ret;
#if defined(CONFIG_DEFAULT_SQ_NONE)
if (q->nr_hw_queues == 1)
return 0;
#endif
#if defined(CONFIG_DEFAULT_MQ_NONE)
if (q->nr_hw_queues > 1)
return 0;
#endif
mutex_lock(&q->sysfs_lock);
ret = elevator_init(q, NULL);
mutex_unlock(&q->sysfs_lock);
return ret;
}

142
block/blk-mq-sched.h Normal file
View File

@ -0,0 +1,142 @@
#ifndef BLK_MQ_SCHED_H
#define BLK_MQ_SCHED_H
#include "blk-mq.h"
#include "blk-mq-tag.h"
int blk_mq_sched_init_hctx_data(struct request_queue *q, size_t size,
int (*init)(struct blk_mq_hw_ctx *),
void (*exit)(struct blk_mq_hw_ctx *));
void blk_mq_sched_free_hctx_data(struct request_queue *q,
void (*exit)(struct blk_mq_hw_ctx *));
struct request *blk_mq_sched_get_request(struct request_queue *q, struct bio *bio, unsigned int op, struct blk_mq_alloc_data *data);
void blk_mq_sched_put_request(struct request *rq);
void blk_mq_sched_request_inserted(struct request *rq);
bool blk_mq_sched_bypass_insert(struct blk_mq_hw_ctx *hctx, struct request *rq);
bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio);
bool __blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio);
bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq);
void blk_mq_sched_restart_queues(struct blk_mq_hw_ctx *hctx);
void blk_mq_sched_insert_request(struct request *rq, bool at_head,
bool run_queue, bool async, bool can_block);
void blk_mq_sched_insert_requests(struct request_queue *q,
struct blk_mq_ctx *ctx,
struct list_head *list, bool run_queue_async);
void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx);
void blk_mq_sched_move_to_dispatch(struct blk_mq_hw_ctx *hctx,
struct list_head *rq_list,
struct request *(*get_rq)(struct blk_mq_hw_ctx *));
int blk_mq_sched_setup(struct request_queue *q);
void blk_mq_sched_teardown(struct request_queue *q);
int blk_mq_sched_init(struct request_queue *q);
static inline bool
blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio)
{
struct elevator_queue *e = q->elevator;
if (!e || blk_queue_nomerges(q) || !bio_mergeable(bio))
return false;
return __blk_mq_sched_bio_merge(q, bio);
}
static inline int blk_mq_sched_get_rq_priv(struct request_queue *q,
struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.get_rq_priv)
return e->type->ops.mq.get_rq_priv(q, rq);
return 0;
}
static inline void blk_mq_sched_put_rq_priv(struct request_queue *q,
struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.put_rq_priv)
e->type->ops.mq.put_rq_priv(q, rq);
}
static inline bool
blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq,
struct bio *bio)
{
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.allow_merge)
return e->type->ops.mq.allow_merge(q, rq, bio);
return true;
}
static inline void
blk_mq_sched_completed_request(struct blk_mq_hw_ctx *hctx, struct request *rq)
{
struct elevator_queue *e = hctx->queue->elevator;
if (e && e->type->ops.mq.completed_request)
e->type->ops.mq.completed_request(hctx, rq);
BUG_ON(rq->internal_tag == -1);
blk_mq_put_tag(hctx, hctx->sched_tags, rq->mq_ctx, rq->internal_tag);
}
static inline void blk_mq_sched_started_request(struct request *rq)
{
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.started_request)
e->type->ops.mq.started_request(rq);
}
static inline void blk_mq_sched_requeue_request(struct request *rq)
{
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
if (e && e->type->ops.mq.requeue_request)
e->type->ops.mq.requeue_request(rq);
}
static inline bool blk_mq_sched_has_work(struct blk_mq_hw_ctx *hctx)
{
struct elevator_queue *e = hctx->queue->elevator;
if (e && e->type->ops.mq.has_work)
return e->type->ops.mq.has_work(hctx);
return false;
}
static inline void blk_mq_sched_mark_restart(struct blk_mq_hw_ctx *hctx)
{
if (!test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state)) {
set_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
if (hctx->flags & BLK_MQ_F_TAG_SHARED) {
struct request_queue *q = hctx->queue;
if (!test_bit(QUEUE_FLAG_RESTART, &q->queue_flags))
set_bit(QUEUE_FLAG_RESTART, &q->queue_flags);
}
}
}
static inline bool blk_mq_sched_needs_restart(struct blk_mq_hw_ctx *hctx)
{
return test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
}
#endif

235
block/blk-mq-sysfs.c
View File

@ -122,123 +122,16 @@ static ssize_t blk_mq_hw_sysfs_store(struct kobject *kobj,
return res;
}
static ssize_t blk_mq_sysfs_dispatched_show(struct blk_mq_ctx *ctx, char *page)
{
return sprintf(page, "%lu %lu\n", ctx->rq_dispatched[1],
ctx->rq_dispatched[0]);
}
static ssize_t blk_mq_sysfs_merged_show(struct blk_mq_ctx *ctx, char *page)
{
return sprintf(page, "%lu\n", ctx->rq_merged);
}
static ssize_t blk_mq_sysfs_completed_show(struct blk_mq_ctx *ctx, char *page)
{
return sprintf(page, "%lu %lu\n", ctx->rq_completed[1],
ctx->rq_completed[0]);
}
static ssize_t sysfs_list_show(char *page, struct list_head *list, char *msg)
{
struct request *rq;
int len = snprintf(page, PAGE_SIZE - 1, "%s:\n", msg);
list_for_each_entry(rq, list, queuelist) {
const int rq_len = 2 * sizeof(rq) + 2;
/* if the output will be truncated */
if (PAGE_SIZE - 1 < len + rq_len) {
/* backspacing if it can't hold '\t...\n' */
if (PAGE_SIZE - 1 < len + 5)
len -= rq_len;
len += snprintf(page + len, PAGE_SIZE - 1 - len,
"\t...\n");
break;
}
len += snprintf(page + len, PAGE_SIZE - 1 - len,
"\t%p\n", rq);
}
return len;
}
static ssize_t blk_mq_sysfs_rq_list_show(struct blk_mq_ctx *ctx, char *page)
{
ssize_t ret;
spin_lock(&ctx->lock);
ret = sysfs_list_show(page, &ctx->rq_list, "CTX pending");
spin_unlock(&ctx->lock);
return ret;
}
static ssize_t blk_mq_hw_sysfs_poll_show(struct blk_mq_hw_ctx *hctx, char *page)
{
return sprintf(page, "considered=%lu, invoked=%lu, success=%lu\n",
hctx->poll_considered, hctx->poll_invoked,
hctx->poll_success);
}
static ssize_t blk_mq_hw_sysfs_poll_store(struct blk_mq_hw_ctx *hctx,
const char *page, size_t size)
{
hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
return size;
}
static ssize_t blk_mq_hw_sysfs_queued_show(struct blk_mq_hw_ctx *hctx,
char *page)
{
return sprintf(page, "%lu\n", hctx->queued);
}
static ssize_t blk_mq_hw_sysfs_run_show(struct blk_mq_hw_ctx *hctx, char *page)
{
return sprintf(page, "%lu\n", hctx->run);
}
static ssize_t blk_mq_hw_sysfs_dispatched_show(struct blk_mq_hw_ctx *hctx,
char *page)
{
char *start_page = page;
int i;
page += sprintf(page, "%8u\t%lu\n", 0U, hctx->dispatched[0]);
for (i = 1; i < BLK_MQ_MAX_DISPATCH_ORDER - 1; i++) {
unsigned int d = 1U << (i - 1);
page += sprintf(page, "%8u\t%lu\n", d, hctx->dispatched[i]);
}
page += sprintf(page, "%8u+\t%lu\n", 1U << (i - 1),
hctx->dispatched[i]);
return page - start_page;
}
static ssize_t blk_mq_hw_sysfs_rq_list_show(struct blk_mq_hw_ctx *hctx,
static ssize_t blk_mq_hw_sysfs_nr_tags_show(struct blk_mq_hw_ctx *hctx,
char *page)
{
ssize_t ret;
spin_lock(&hctx->lock);
ret = sysfs_list_show(page, &hctx->dispatch, "HCTX pending");
spin_unlock(&hctx->lock);
return ret;
return sprintf(page, "%u\n", hctx->tags->nr_tags);
}
static ssize_t blk_mq_hw_sysfs_tags_show(struct blk_mq_hw_ctx *hctx, char *page)
static ssize_t blk_mq_hw_sysfs_nr_reserved_tags_show(struct blk_mq_hw_ctx *hctx,
char *page)
{
return blk_mq_tag_sysfs_show(hctx->tags, page);
}
static ssize_t blk_mq_hw_sysfs_active_show(struct blk_mq_hw_ctx *hctx, char *page)
{
return sprintf(page, "%u\n", atomic_read(&hctx->nr_active));
return sprintf(page, "%u\n", hctx->tags->nr_reserved_tags);
}
static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
@ -259,121 +152,27 @@ static ssize_t blk_mq_hw_sysfs_cpus_show(struct blk_mq_hw_ctx *hctx, char *page)
return ret;
}
static void blk_mq_stat_clear(struct blk_mq_hw_ctx *hctx)
{
struct blk_mq_ctx *ctx;
unsigned int i;
hctx_for_each_ctx(hctx, ctx, i) {
blk_stat_init(&ctx->stat[BLK_STAT_READ]);
blk_stat_init(&ctx->stat[BLK_STAT_WRITE]);
}
}
static ssize_t blk_mq_hw_sysfs_stat_store(struct blk_mq_hw_ctx *hctx,
const char *page, size_t count)
{
blk_mq_stat_clear(hctx);
return count;
}
static ssize_t print_stat(char *page, struct blk_rq_stat *stat, const char *pre)
{
return sprintf(page, "%s samples=%llu, mean=%lld, min=%lld, max=%lld\n",
pre, (long long) stat->nr_samples,
(long long) stat->mean, (long long) stat->min,
(long long) stat->max);
}
static ssize_t blk_mq_hw_sysfs_stat_show(struct blk_mq_hw_ctx *hctx, char *page)
{
struct blk_rq_stat stat[2];
ssize_t ret;
blk_stat_init(&stat[BLK_STAT_READ]);
blk_stat_init(&stat[BLK_STAT_WRITE]);
blk_hctx_stat_get(hctx, stat);
ret = print_stat(page, &stat[BLK_STAT_READ], "read :");
ret += print_stat(page + ret, &stat[BLK_STAT_WRITE], "write:");
return ret;
}
static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_dispatched = {
.attr = {.name = "dispatched", .mode = S_IRUGO },
.show = blk_mq_sysfs_dispatched_show,
};
static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_merged = {
.attr = {.name = "merged", .mode = S_IRUGO },
.show = blk_mq_sysfs_merged_show,
};
static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_completed = {
.attr = {.name = "completed", .mode = S_IRUGO },
.show = blk_mq_sysfs_completed_show,
};
static struct blk_mq_ctx_sysfs_entry blk_mq_sysfs_rq_list = {
.attr = {.name = "rq_list", .mode = S_IRUGO },
.show = blk_mq_sysfs_rq_list_show,
};
static struct attribute *default_ctx_attrs[] = {
&blk_mq_sysfs_dispatched.attr,
&blk_mq_sysfs_merged.attr,
&blk_mq_sysfs_completed.attr,
&blk_mq_sysfs_rq_list.attr,
NULL,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_queued = {
.attr = {.name = "queued", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_queued_show,
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_tags = {
.attr = {.name = "nr_tags", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_nr_tags_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_run = {
.attr = {.name = "run", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_run_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_dispatched = {
.attr = {.name = "dispatched", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_dispatched_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_active = {
.attr = {.name = "active", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_active_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_pending = {
.attr = {.name = "pending", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_rq_list_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_tags = {
.attr = {.name = "tags", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_tags_show,
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_nr_reserved_tags = {
.attr = {.name = "nr_reserved_tags", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_nr_reserved_tags_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_cpus = {
.attr = {.name = "cpu_list", .mode = S_IRUGO },
.show = blk_mq_hw_sysfs_cpus_show,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_poll = {
.attr = {.name = "io_poll", .mode = S_IWUSR | S_IRUGO },
.show = blk_mq_hw_sysfs_poll_show,
.store = blk_mq_hw_sysfs_poll_store,
};
static struct blk_mq_hw_ctx_sysfs_entry blk_mq_hw_sysfs_stat = {
.attr = {.name = "stats", .mode = S_IRUGO | S_IWUSR },
.show = blk_mq_hw_sysfs_stat_show,
.store = blk_mq_hw_sysfs_stat_store,
};
static struct attribute *default_hw_ctx_attrs[] = {
&blk_mq_hw_sysfs_queued.attr,
&blk_mq_hw_sysfs_run.attr,
&blk_mq_hw_sysfs_dispatched.attr,
&blk_mq_hw_sysfs_pending.attr,
&blk_mq_hw_sysfs_tags.attr,
&blk_mq_hw_sysfs_nr_tags.attr,
&blk_mq_hw_sysfs_nr_reserved_tags.attr,
&blk_mq_hw_sysfs_cpus.attr,
&blk_mq_hw_sysfs_active.attr,
&blk_mq_hw_sysfs_poll.attr,
&blk_mq_hw_sysfs_stat.attr,
NULL,
};
@ -455,6 +254,8 @@ static void __blk_mq_unregister_dev(struct device *dev, struct request_queue *q)
kobject_put(&hctx->kobj);
}
blk_mq_debugfs_unregister(q);
kobject_uevent(&q->mq_kobj, KOBJ_REMOVE);
kobject_del(&q->mq_kobj);
kobject_put(&q->mq_kobj);
@ -504,6 +305,8 @@ int blk_mq_register_dev(struct device *dev, struct request_queue *q)
kobject_uevent(&q->mq_kobj, KOBJ_ADD);
blk_mq_debugfs_register(q, kobject_name(&dev->kobj));
queue_for_each_hw_ctx(q, hctx, i) {
ret = blk_mq_register_hctx(hctx);
if (ret)
@ -529,6 +332,8 @@ void blk_mq_sysfs_unregister(struct request_queue *q)
if (!q->mq_sysfs_init_done)
return;
blk_mq_debugfs_unregister_hctxs(q);
queue_for_each_hw_ctx(q, hctx, i)
blk_mq_unregister_hctx(hctx);
}
@ -541,6 +346,8 @@ int blk_mq_sysfs_register(struct request_queue *q)
if (!q->mq_sysfs_init_done)
return ret;
blk_mq_debugfs_register_hctxs(q);
queue_for_each_hw_ctx(q, hctx, i) {
ret = blk_mq_register_hctx(hctx);
if (ret)

196
block/blk-mq-tag.c
View File

@ -90,113 +90,97 @@ static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
return atomic_read(&hctx->nr_active) < depth;
}
static int __bt_get(struct blk_mq_hw_ctx *hctx, struct sbitmap_queue *bt)
static int __blk_mq_get_tag(struct blk_mq_alloc_data *data,
struct sbitmap_queue *bt)
{
if (!hctx_may_queue(hctx, bt))
if (!(data->flags & BLK_MQ_REQ_INTERNAL) &&
!hctx_may_queue(data->hctx, bt))
return -1;
return __sbitmap_queue_get(bt);
}
static int bt_get(struct blk_mq_alloc_data *data, struct sbitmap_queue *bt,
struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags)
unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
{
struct blk_mq_tags *tags = blk_mq_tags_from_data(data);
struct sbitmap_queue *bt;
struct sbq_wait_state *ws;
DEFINE_WAIT(wait);
unsigned int tag_offset;
bool drop_ctx;
int tag;
tag = __bt_get(hctx, bt);
if (data->flags & BLK_MQ_REQ_RESERVED) {
if (unlikely(!tags->nr_reserved_tags)) {
WARN_ON_ONCE(1);
return BLK_MQ_TAG_FAIL;
}
bt = &tags->breserved_tags;
tag_offset = 0;
} else {
bt = &tags->bitmap_tags;
tag_offset = tags->nr_reserved_tags;
}
tag = __blk_mq_get_tag(data, bt);
if (tag != -1)
return tag;
goto found_tag;
if (data->flags & BLK_MQ_REQ_NOWAIT)
return -1;
return BLK_MQ_TAG_FAIL;
ws = bt_wait_ptr(bt, hctx);
ws = bt_wait_ptr(bt, data->hctx);
drop_ctx = data->ctx == NULL;
do {
prepare_to_wait(&ws->wait, &wait, TASK_UNINTERRUPTIBLE);
tag = __bt_get(hctx, bt);
tag = __blk_mq_get_tag(data, bt);
if (tag != -1)
break;
/*
* We're out of tags on this hardware queue, kick any
* pending IO submits before going to sleep waiting for
* some to complete. Note that hctx can be NULL here for
* reserved tag allocation.
* some to complete.
*/
if (hctx)
blk_mq_run_hw_queue(hctx, false);
blk_mq_run_hw_queue(data->hctx, false);
/*
* Retry tag allocation after running the hardware queue,
* as running the queue may also have found completions.
*/
tag = __bt_get(hctx, bt);
tag = __blk_mq_get_tag(data, bt);
if (tag != -1)
break;
blk_mq_put_ctx(data->ctx);
if (data->ctx)
blk_mq_put_ctx(data->ctx);
io_schedule();
data->ctx = blk_mq_get_ctx(data->q);
data->hctx = blk_mq_map_queue(data->q, data->ctx->cpu);
if (data->flags & BLK_MQ_REQ_RESERVED) {
bt = &data->hctx->tags->breserved_tags;
} else {
hctx = data->hctx;
bt = &hctx->tags->bitmap_tags;
}
tags = blk_mq_tags_from_data(data);
if (data->flags & BLK_MQ_REQ_RESERVED)
bt = &tags->breserved_tags;
else
bt = &tags->bitmap_tags;
finish_wait(&ws->wait, &wait);
ws = bt_wait_ptr(bt, hctx);
ws = bt_wait_ptr(bt, data->hctx);
} while (1);
if (drop_ctx && data->ctx)
blk_mq_put_ctx(data->ctx);
finish_wait(&ws->wait, &wait);
return tag;
found_tag:
return tag + tag_offset;
}
static unsigned int __blk_mq_get_tag(struct blk_mq_alloc_data *data)
void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags,
struct blk_mq_ctx *ctx, unsigned int tag)
{
int tag;
tag = bt_get(data, &data->hctx->tags->bitmap_tags, data->hctx,
data->hctx->tags);
if (tag >= 0)
return tag + data->hctx->tags->nr_reserved_tags;
return BLK_MQ_TAG_FAIL;
}
static unsigned int __blk_mq_get_reserved_tag(struct blk_mq_alloc_data *data)
{
int tag;
if (unlikely(!data->hctx->tags->nr_reserved_tags)) {
WARN_ON_ONCE(1);
return BLK_MQ_TAG_FAIL;
}
tag = bt_get(data, &data->hctx->tags->breserved_tags, NULL,
data->hctx->tags);
if (tag < 0)
return BLK_MQ_TAG_FAIL;
return tag;
}
unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data)
{
if (data->flags & BLK_MQ_REQ_RESERVED)
return __blk_mq_get_reserved_tag(data);
return __blk_mq_get_tag(data);
}
void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
unsigned int tag)
{
struct blk_mq_tags *tags = hctx->tags;
if (tag >= tags->nr_reserved_tags) {
const int real_tag = tag - tags->nr_reserved_tags;
@ -312,11 +296,11 @@ int blk_mq_reinit_tagset(struct blk_mq_tag_set *set)
struct blk_mq_tags *tags = set->tags[i];
for (j = 0; j < tags->nr_tags; j++) {
if (!tags->rqs[j])
if (!tags->static_rqs[j])
continue;
ret = set->ops->reinit_request(set->driver_data,
tags->rqs[j]);
tags->static_rqs[j]);
if (ret)
goto out;
}
@ -351,11 +335,6 @@ void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
}
static unsigned int bt_unused_tags(const struct sbitmap_queue *bt)
{
return bt->sb.depth - sbitmap_weight(&bt->sb);
}
static int bt_alloc(struct sbitmap_queue *bt, unsigned int depth,
bool round_robin, int node)
{
@ -411,19 +390,56 @@ void blk_mq_free_tags(struct blk_mq_tags *tags)
kfree(tags);
}
int blk_mq_tag_update_depth(struct blk_mq_tags *tags, unsigned int tdepth)
int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
struct blk_mq_tags **tagsptr, unsigned int tdepth,
bool can_grow)
{
tdepth -= tags->nr_reserved_tags;
if (tdepth > tags->nr_tags)
struct blk_mq_tags *tags = *tagsptr;
if (tdepth <= tags->nr_reserved_tags)
return -EINVAL;
/*
* Don't need (or can't) update reserved tags here, they remain
* static and should never need resizing.
*/
sbitmap_queue_resize(&tags->bitmap_tags, tdepth);
tdepth -= tags->nr_reserved_tags;
/*
* If we are allowed to grow beyond the original size, allocate
* a new set of tags before freeing the old one.
*/
if (tdepth > tags->nr_tags) {
struct blk_mq_tag_set *set = hctx->queue->tag_set;
struct blk_mq_tags *new;
bool ret;
if (!can_grow)
return -EINVAL;
/*
* We need some sort of upper limit, set it high enough that
* no valid use cases should require more.
*/
if (tdepth > 16 * BLKDEV_MAX_RQ)
return -EINVAL;
new = blk_mq_alloc_rq_map(set, hctx->queue_num, tdepth, 0);
if (!new)
return -ENOMEM;
ret = blk_mq_alloc_rqs(set, new, hctx->queue_num, tdepth);
if (ret) {
blk_mq_free_rq_map(new);
return -ENOMEM;
}
blk_mq_free_rqs(set, *tagsptr, hctx->queue_num);
blk_mq_free_rq_map(*tagsptr);
*tagsptr = new;
} else {
/*
* Don't need (or can't) update reserved tags here, they
* remain static and should never need resizing.
*/
sbitmap_queue_resize(&tags->bitmap_tags, tdepth);
}
blk_mq_tag_wakeup_all(tags, false);
return 0;
}
@ -454,25 +470,3 @@ u32 blk_mq_unique_tag(struct request *rq)
(rq->tag & BLK_MQ_UNIQUE_TAG_MASK);
}
EXPORT_SYMBOL(blk_mq_unique_tag);
ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page)
{
char *orig_page = page;
unsigned int free, res;
if (!tags)
return 0;
page += sprintf(page, "nr_tags=%u, reserved_tags=%u, "
"bits_per_word=%u\n",
tags->nr_tags, tags->nr_reserved_tags,
1U << tags->bitmap_tags.sb.shift);
free = bt_unused_tags(&tags->bitmap_tags);
res = bt_unused_tags(&tags->breserved_tags);
page += sprintf(page, "nr_free=%u, nr_reserved=%u\n", free, res);
page += sprintf(page, "active_queues=%u\n", atomic_read(&tags->active_queues));
return page - orig_page;
}

10
block/blk-mq-tag.h
View File

@ -16,6 +16,7 @@ struct blk_mq_tags {
struct sbitmap_queue breserved_tags;
struct request **rqs;
struct request **static_rqs;
struct list_head page_list;
};
@ -24,11 +25,12 @@ extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int r
extern void blk_mq_free_tags(struct blk_mq_tags *tags);
extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
extern void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
unsigned int tag);
extern void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags,
struct blk_mq_ctx *ctx, unsigned int tag);
extern bool blk_mq_has_free_tags(struct blk_mq_tags *tags);
extern ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page);
extern int blk_mq_tag_update_depth(struct blk_mq_tags *tags, unsigned int depth);
extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
struct blk_mq_tags **tags,
unsigned int depth, bool can_grow);
extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
void *priv);

560
block/blk-mq.c
View File

File diff suppressed because it is too large Load Diff

77
block/blk-mq.h
View File

@ -32,7 +32,31 @@ void blk_mq_free_queue(struct request_queue *q);
int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
void blk_mq_wake_waiters(struct request_queue *q);
bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *, struct list_head *);
void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx);
bool blk_mq_get_driver_tag(struct request *rq, struct blk_mq_hw_ctx **hctx,
bool wait);
/*
* Internal helpers for allocating/freeing the request map
*/
void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
unsigned int hctx_idx);
void blk_mq_free_rq_map(struct blk_mq_tags *tags);
struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
unsigned int hctx_idx,
unsigned int nr_tags,
unsigned int reserved_tags);
int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
unsigned int hctx_idx, unsigned int depth);
/*
* Internal helpers for request insertion into sw queues
*/
void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
bool at_head);
void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
struct list_head *list);
/*
* CPU hotplug helpers
*/
@ -57,6 +81,40 @@ extern int blk_mq_sysfs_register(struct request_queue *q);
extern void blk_mq_sysfs_unregister(struct request_queue *q);
extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
/*
* debugfs helpers
*/
#ifdef CONFIG_BLK_DEBUG_FS
void blk_mq_debugfs_init(void);
int blk_mq_debugfs_register(struct request_queue *q, const char *name);
void blk_mq_debugfs_unregister(struct request_queue *q);
int blk_mq_debugfs_register_hctxs(struct request_queue *q);
void blk_mq_debugfs_unregister_hctxs(struct request_queue *q);
#else
static inline void blk_mq_debugfs_init(void)
{
}
static inline int blk_mq_debugfs_register(struct request_queue *q,
const char *name)
{
return 0;
}
static inline void blk_mq_debugfs_unregister(struct request_queue *q)
{
}
static inline int blk_mq_debugfs_register_hctxs(struct request_queue *q)
{
return 0;
}
static inline void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
{
}
#endif
extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
void blk_mq_release(struct request_queue *q);
@ -103,6 +161,25 @@ static inline void blk_mq_set_alloc_data(struct blk_mq_alloc_data *data,
data->hctx = hctx;
}
static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
{
if (data->flags & BLK_MQ_REQ_INTERNAL)
return data->hctx->sched_tags;
return data->hctx->tags;
}
/*
* Internal helpers for request allocation/init/free
*/
void blk_mq_rq_ctx_init(struct request_queue *q, struct blk_mq_ctx *ctx,
struct request *rq, unsigned int op);
void __blk_mq_finish_request(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
struct request *rq);
void blk_mq_finish_request(struct request *rq);
struct request *__blk_mq_alloc_request(struct blk_mq_alloc_data *data,
unsigned int op);
static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
{
return test_bit(BLK_MQ_S_STOPPED, &hctx->state);

1
block/blk-tag.c
View File

@ -272,6 +272,7 @@ void blk_queue_end_tag(struct request_queue *q, struct request *rq)
list_del_init(&rq->queuelist);
rq->rq_flags &= ~RQF_QUEUED;
rq->tag = -1;
rq->internal_tag = -1;
if (unlikely(bqt->tag_index[tag] == NULL))
printk(KERN_ERR "%s: tag %d is missing\n",

6
block/blk-throttle.c
View File

@ -866,10 +866,12 @@ static void tg_update_disptime(struct throtl_grp *tg)
unsigned long read_wait = -1, write_wait = -1, min_wait = -1, disptime;
struct bio *bio;
if ((bio = throtl_peek_queued(&sq->queued[READ])))
bio = throtl_peek_queued(&sq->queued[READ]);
if (bio)
tg_may_dispatch(tg, bio, &read_wait);
if ((bio = throtl_peek_queued(&sq->queued[WRITE])))
bio = throtl_peek_queued(&sq->queued[WRITE]);
if (bio)
tg_may_dispatch(tg, bio, &write_wait);
min_wait = min(read_wait, write_wait);

26
block/blk.h
View File

@ -167,7 +167,7 @@ static inline struct request *__elv_next_request(struct request_queue *q)
return NULL;
}
if (unlikely(blk_queue_bypass(q)) ||
!q->elevator->type->ops.elevator_dispatch_fn(q, 0))
!q->elevator->type->ops.sq.elevator_dispatch_fn(q, 0))
return NULL;
}
}
@ -176,16 +176,16 @@ static inline void elv_activate_rq(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_activate_req_fn)
e->type->ops.elevator_activate_req_fn(q, rq);
if (e->type->ops.sq.elevator_activate_req_fn)
e->type->ops.sq.elevator_activate_req_fn(q, rq);
}
static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_deactivate_req_fn)
e->type->ops.elevator_deactivate_req_fn(q, rq);
if (e->type->ops.sq.elevator_deactivate_req_fn)
e->type->ops.sq.elevator_deactivate_req_fn(q, rq);
}
#ifdef CONFIG_FAIL_IO_TIMEOUT
@ -263,6 +263,22 @@ void ioc_clear_queue(struct request_queue *q);
int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node);
/**
* rq_ioc - determine io_context for request allocation
* @bio: request being allocated is for this bio (can be %NULL)
*
* Determine io_context to use for request allocation for @bio. May return
* %NULL if %current->io_context doesn't exist.
*/
static inline struct io_context *rq_ioc(struct bio *bio)
{
#ifdef CONFIG_BLK_CGROUP
if (bio && bio->bi_ioc)
return bio->bi_ioc;
#endif
return current->io_context;
}
/**
* create_io_context - try to create task->io_context
* @gfp_mask: allocation mask

10
block/cfq-iosched.c
View File

@ -2749,9 +2749,11 @@ static struct cfq_queue *cfq_get_next_queue_forced(struct cfq_data *cfqd)
if (!cfqg)
return NULL;
for_each_cfqg_st(cfqg, i, j, st)
if ((cfqq = cfq_rb_first(st)) != NULL)
for_each_cfqg_st(cfqg, i, j, st) {
cfqq = cfq_rb_first(st);
if (cfqq)
return cfqq;
}
return NULL;
}
@ -3864,6 +3866,8 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic,
goto out;
}
/* cfq_init_cfqq() assumes cfqq->ioprio_class is initialized. */
cfqq->ioprio_class = IOPRIO_CLASS_NONE;
cfq_init_cfqq(cfqd, cfqq, current->pid, is_sync);
cfq_init_prio_data(cfqq, cic);
cfq_link_cfqq_cfqg(cfqq, cfqg);
@ -4837,7 +4841,7 @@ static struct elv_fs_entry cfq_attrs[] = {
};
static struct elevator_type iosched_cfq = {
.ops = {
.ops.sq = {
.elevator_merge_fn = cfq_merge,
.elevator_merged_fn = cfq_merged_request,
.elevator_merge_req_fn = cfq_merged_requests,

2
block/deadline-iosched.c
View File

@ -439,7 +439,7 @@ static struct elv_fs_entry deadline_attrs[] = {
};
static struct elevator_type iosched_deadline = {
.ops = {
.ops.sq = {
.elevator_merge_fn = deadline_merge,
.elevator_merged_fn = deadline_merged_request,
.elevator_merge_req_fn = deadline_merged_requests,

242
block/elevator.c
View File

@ -40,6 +40,7 @@
#include <trace/events/block.h>
#include "blk.h"
#include "blk-mq-sched.h"
static DEFINE_SPINLOCK(elv_list_lock);
static LIST_HEAD(elv_list);
@ -58,8 +59,10 @@ static int elv_iosched_allow_bio_merge(struct request *rq, struct bio *bio)
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_allow_bio_merge_fn)
return e->type->ops.elevator_allow_bio_merge_fn(q, rq, bio);
if (e->uses_mq && e->type->ops.mq.allow_merge)
return e->type->ops.mq.allow_merge(q, rq, bio);
else if (!e->uses_mq && e->type->ops.sq.elevator_allow_bio_merge_fn)
return e->type->ops.sq.elevator_allow_bio_merge_fn(q, rq, bio);
return 1;
}
@ -163,6 +166,7 @@ struct elevator_queue *elevator_alloc(struct request_queue *q,
kobject_init(&eq->kobj, &elv_ktype);
mutex_init(&eq->sysfs_lock);
hash_init(eq->hash);
eq->uses_mq = e->uses_mq;
return eq;
}
@ -215,18 +219,32 @@ int elevator_init(struct request_queue *q, char *name)
}
if (!e) {
e = elevator_get(CONFIG_DEFAULT_IOSCHED, false);
if (q->mq_ops && q->nr_hw_queues == 1)
e = elevator_get(CONFIG_DEFAULT_SQ_IOSCHED, false);
else if (q->mq_ops)
e = elevator_get(CONFIG_DEFAULT_MQ_IOSCHED, false);
else
e = elevator_get(CONFIG_DEFAULT_IOSCHED, false);
if (!e) {
printk(KERN_ERR
"Default I/O scheduler not found. " \
"Using noop.\n");
"Using noop/none.\n");
e = elevator_get("noop", false);
}
}
err = e->ops.elevator_init_fn(q, e);
if (err)
if (e->uses_mq) {
err = blk_mq_sched_setup(q);
if (!err)
err = e->ops.mq.init_sched(q, e);
} else
err = e->ops.sq.elevator_init_fn(q, e);
if (err) {
if (e->uses_mq)
blk_mq_sched_teardown(q);
elevator_put(e);
}
return err;
}
EXPORT_SYMBOL(elevator_init);
@ -234,8 +252,10 @@ EXPORT_SYMBOL(elevator_init);
void elevator_exit(struct elevator_queue *e)
{
mutex_lock(&e->sysfs_lock);
if (e->type->ops.elevator_exit_fn)
e->type->ops.elevator_exit_fn(e);
if (e->uses_mq && e->type->ops.mq.exit_sched)
e->type->ops.mq.exit_sched(e);
else if (!e->uses_mq && e->type->ops.sq.elevator_exit_fn)
e->type->ops.sq.elevator_exit_fn(e);
mutex_unlock(&e->sysfs_lock);
kobject_put(&e->kobj);
@ -253,6 +273,7 @@ void elv_rqhash_del(struct request_queue *q, struct request *rq)
if (ELV_ON_HASH(rq))
__elv_rqhash_del(rq);
}
EXPORT_SYMBOL_GPL(elv_rqhash_del);
void elv_rqhash_add(struct request_queue *q, struct request *rq)
{
@ -262,6 +283,7 @@ void elv_rqhash_add(struct request_queue *q, struct request *rq)
hash_add(e->hash, &rq->hash, rq_hash_key(rq));
rq->rq_flags |= RQF_HASHED;
}
EXPORT_SYMBOL_GPL(elv_rqhash_add);
void elv_rqhash_reposition(struct request_queue *q, struct request *rq)
{
@ -443,8 +465,10 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
return ELEVATOR_BACK_MERGE;
}
if (e->type->ops.elevator_merge_fn)
return e->type->ops.elevator_merge_fn(q, req, bio);
if (e->uses_mq && e->type->ops.mq.request_merge)
return e->type->ops.mq.request_merge(q, req, bio);
else if (!e->uses_mq && e->type->ops.sq.elevator_merge_fn)
return e->type->ops.sq.elevator_merge_fn(q, req, bio);
return ELEVATOR_NO_MERGE;
}
@ -456,8 +480,7 @@ int elv_merge(struct request_queue *q, struct request **req, struct bio *bio)
*
* Returns true if we merged, false otherwise
*/
static bool elv_attempt_insert_merge(struct request_queue *q,
struct request *rq)
bool elv_attempt_insert_merge(struct request_queue *q, struct request *rq)
{
struct request *__rq;
bool ret;
@ -495,8 +518,10 @@ void elv_merged_request(struct request_queue *q, struct request *rq, int type)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_merged_fn)
e->type->ops.elevator_merged_fn(q, rq, type);
if (e->uses_mq && e->type->ops.mq.request_merged)
e->type->ops.mq.request_merged(q, rq, type);
else if (!e->uses_mq && e->type->ops.sq.elevator_merged_fn)
e->type->ops.sq.elevator_merged_fn(q, rq, type);
if (type == ELEVATOR_BACK_MERGE)
elv_rqhash_reposition(q, rq);
@ -508,10 +533,15 @@ void elv_merge_requests(struct request_queue *q, struct request *rq,
struct request *next)
{
struct elevator_queue *e = q->elevator;
const int next_sorted = next->rq_flags & RQF_SORTED;
bool next_sorted = false;
if (next_sorted && e->type->ops.elevator_merge_req_fn)
e->type->ops.elevator_merge_req_fn(q, rq, next);
if (e->uses_mq && e->type->ops.mq.requests_merged)
e->type->ops.mq.requests_merged(q, rq, next);
else if (e->type->ops.sq.elevator_merge_req_fn) {
next_sorted = next->rq_flags & RQF_SORTED;
if (next_sorted)
e->type->ops.sq.elevator_merge_req_fn(q, rq, next);
}
elv_rqhash_reposition(q, rq);
@ -528,8 +558,11 @@ void elv_bio_merged(struct request_queue *q, struct request *rq,
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_bio_merged_fn)
e->type->ops.elevator_bio_merged_fn(q, rq, bio);
if (WARN_ON_ONCE(e->uses_mq))
return;
if (e->type->ops.sq.elevator_bio_merged_fn)
e->type->ops.sq.elevator_bio_merged_fn(q, rq, bio);
}
#ifdef CONFIG_PM
@ -574,11 +607,15 @@ void elv_requeue_request(struct request_queue *q, struct request *rq)
void elv_drain_elevator(struct request_queue *q)
{
struct elevator_queue *e = q->elevator;
static int printed;
if (WARN_ON_ONCE(e->uses_mq))
return;
lockdep_assert_held(q->queue_lock);
while (q->elevator->type->ops.elevator_dispatch_fn(q, 1))
while (e->type->ops.sq.elevator_dispatch_fn(q, 1))
;
if (q->nr_sorted && printed++ < 10) {
printk(KERN_ERR "%s: forced dispatching is broken "
@ -653,7 +690,7 @@ void __elv_add_request(struct request_queue *q, struct request *rq, int where)
* rq cannot be accessed after calling
* elevator_add_req_fn.
*/
q->elevator->type->ops.elevator_add_req_fn(q, rq);
q->elevator->type->ops.sq.elevator_add_req_fn(q, rq);
break;
case ELEVATOR_INSERT_FLUSH:
@ -682,8 +719,11 @@ struct request *elv_latter_request(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_latter_req_fn)
return e->type->ops.elevator_latter_req_fn(q, rq);
if (e->uses_mq && e->type->ops.mq.next_request)
return e->type->ops.mq.next_request(q, rq);
else if (!e->uses_mq && e->type->ops.sq.elevator_latter_req_fn)
return e->type->ops.sq.elevator_latter_req_fn(q, rq);
return NULL;
}
@ -691,8 +731,10 @@ struct request *elv_former_request(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_former_req_fn)
return e->type->ops.elevator_former_req_fn(q, rq);
if (e->uses_mq && e->type->ops.mq.former_request)
return e->type->ops.mq.former_request(q, rq);
if (!e->uses_mq && e->type->ops.sq.elevator_former_req_fn)
return e->type->ops.sq.elevator_former_req_fn(q, rq);
return NULL;
}
@ -701,8 +743,11 @@ int elv_set_request(struct request_queue *q, struct request *rq,
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_set_req_fn)
return e->type->ops.elevator_set_req_fn(q, rq, bio, gfp_mask);
if (WARN_ON_ONCE(e->uses_mq))
return 0;
if (e->type->ops.sq.elevator_set_req_fn)
return e->type->ops.sq.elevator_set_req_fn(q, rq, bio, gfp_mask);
return 0;
}
@ -710,16 +755,22 @@ void elv_put_request(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_put_req_fn)
e->type->ops.elevator_put_req_fn(rq);
if (WARN_ON_ONCE(e->uses_mq))
return;
if (e->type->ops.sq.elevator_put_req_fn)
e->type->ops.sq.elevator_put_req_fn(rq);
}
int elv_may_queue(struct request_queue *q, unsigned int op)
{
struct elevator_queue *e = q->elevator;
if (e->type->ops.elevator_may_queue_fn)
return e->type->ops.elevator_may_queue_fn(q, op);
if (WARN_ON_ONCE(e->uses_mq))
return 0;
if (e->type->ops.sq.elevator_may_queue_fn)
return e->type->ops.sq.elevator_may_queue_fn(q, op);
return ELV_MQUEUE_MAY;
}
@ -728,14 +779,17 @@ void elv_completed_request(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
if (WARN_ON_ONCE(e->uses_mq))
return;
/*
* request is released from the driver, io must be done
*/
if (blk_account_rq(rq)) {
q->in_flight[rq_is_sync(rq)]--;
if ((rq->rq_flags & RQF_SORTED) &&
e->type->ops.elevator_completed_req_fn)
e->type->ops.elevator_completed_req_fn(q, rq);
e->type->ops.sq.elevator_completed_req_fn)
e->type->ops.sq.elevator_completed_req_fn(q, rq);
}
}
@ -803,8 +857,8 @@ int elv_register_queue(struct request_queue *q)
}
kobject_uevent(&e->kobj, KOBJ_ADD);
e->registered = 1;
if (e->type->ops.elevator_registered_fn)
e->type->ops.elevator_registered_fn(q);
if (!e->uses_mq && e->type->ops.sq.elevator_registered_fn)
e->type->ops.sq.elevator_registered_fn(q);
}
return error;
}
@ -891,9 +945,14 @@ EXPORT_SYMBOL_GPL(elv_unregister);
static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
{
struct elevator_queue *old = q->elevator;
bool registered = old->registered;
bool old_registered = false;
int err;
if (q->mq_ops) {
blk_mq_freeze_queue(q);
blk_mq_quiesce_queue(q);
}
/*
* Turn on BYPASS and drain all requests w/ elevator private data.
* Block layer doesn't call into a quiesced elevator - all requests
@ -901,42 +960,76 @@ static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
* using INSERT_BACK. All requests have SOFTBARRIER set and no
* merge happens either.
*/
blk_queue_bypass_start(q);
if (old) {
old_registered = old->registered;
/* unregister and clear all auxiliary data of the old elevator */
if (registered)
elv_unregister_queue(q);
if (old->uses_mq)
blk_mq_sched_teardown(q);
spin_lock_irq(q->queue_lock);
ioc_clear_queue(q);
spin_unlock_irq(q->queue_lock);
if (!q->mq_ops)
blk_queue_bypass_start(q);
/* unregister and clear all auxiliary data of the old elevator */
if (old_registered)
elv_unregister_queue(q);
spin_lock_irq(q->queue_lock);
ioc_clear_queue(q);
spin_unlock_irq(q->queue_lock);
}
/* allocate, init and register new elevator */
err = new_e->ops.elevator_init_fn(q, new_e);
if (err)
goto fail_init;
if (new_e) {
if (new_e->uses_mq) {
err = blk_mq_sched_setup(q);
if (!err)
err = new_e->ops.mq.init_sched(q, new_e);
} else
err = new_e->ops.sq.elevator_init_fn(q, new_e);
if (err)
goto fail_init;
if (registered) {
err = elv_register_queue(q);
if (err)
goto fail_register;
}
} else
q->elevator = NULL;
/* done, kill the old one and finish */
elevator_exit(old);
blk_queue_bypass_end(q);
if (old) {
elevator_exit(old);
if (!q->mq_ops)
blk_queue_bypass_end(q);
}
blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name);
if (q->mq_ops) {
blk_mq_unfreeze_queue(q);
blk_mq_start_stopped_hw_queues(q, true);
}
if (new_e)
blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name);
else
blk_add_trace_msg(q, "elv switch: none");
return 0;
fail_register:
if (q->mq_ops)
blk_mq_sched_teardown(q);
elevator_exit(q->elevator);
fail_init:
/* switch failed, restore and re-register old elevator */
q->elevator = old;
elv_register_queue(q);
blk_queue_bypass_end(q);
if (old) {
q->elevator = old;
elv_register_queue(q);
if (!q->mq_ops)
blk_queue_bypass_end(q);
}
if (q->mq_ops) {
blk_mq_unfreeze_queue(q);
blk_mq_start_stopped_hw_queues(q, true);
}
return err;
}
@ -949,8 +1042,11 @@ static int __elevator_change(struct request_queue *q, const char *name)
char elevator_name[ELV_NAME_MAX];
struct elevator_type *e;
if (!q->elevator)
return -ENXIO;
/*
* Special case for mq, turn off scheduling
*/
if (q->mq_ops && !strncmp(name, "none", 4))
return elevator_switch(q, NULL);
strlcpy(elevator_name, name, sizeof(elevator_name));
e = elevator_get(strstrip(elevator_name), true);
@ -959,11 +1055,21 @@ static int __elevator_change(struct request_queue *q, const char *name)
return -EINVAL;
}
if (!strcmp(elevator_name, q->elevator->type->elevator_name)) {
if (q->elevator &&
!strcmp(elevator_name, q->elevator->type->elevator_name)) {
elevator_put(e);
return 0;
}
if (!e->uses_mq && q->mq_ops) {
elevator_put(e);
return -EINVAL;
}
if (e->uses_mq && !q->mq_ops) {
elevator_put(e);
return -EINVAL;
}
return elevator_switch(q, e);
}
@ -985,7 +1091,7 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
{
int ret;
if (!q->elevator)
if (!(q->mq_ops || q->request_fn))
return count;
ret = __elevator_change(q, name);
@ -999,24 +1105,34 @@ ssize_t elv_iosched_store(struct request_queue *q, const char *name,
ssize_t elv_iosched_show(struct request_queue *q, char *name)
{
struct elevator_queue *e = q->elevator;
struct elevator_type *elv;
struct elevator_type *elv = NULL;
struct elevator_type *__e;
int len = 0;
if (!q->elevator || !blk_queue_stackable(q))
if (!blk_queue_stackable(q))
return sprintf(name, "none\n");
elv = e->type;
if (!q->elevator)
len += sprintf(name+len, "[none] ");
else
elv = e->type;
spin_lock(&elv_list_lock);
list_for_each_entry(__e, &elv_list, list) {
if (!strcmp(elv->elevator_name, __e->elevator_name))
if (elv && !strcmp(elv->elevator_name, __e->elevator_name)) {
len += sprintf(name+len, "[%s] ", elv->elevator_name);
else
continue;
}
if (__e->uses_mq && q->mq_ops)
len += sprintf(name+len, "%s ", __e->elevator_name);
else if (!__e->uses_mq && !q->mq_ops)
len += sprintf(name+len, "%s ", __e->elevator_name);
}
spin_unlock(&elv_list_lock);
if (q->mq_ops && q->elevator)
len += sprintf(name+len, "none");
len += sprintf(len+name, "\n");
return len;
}

555
block/mq-deadline.c Normal file
View File

@ -0,0 +1,555 @@
/*
* MQ Deadline i/o scheduler - adaptation of the legacy deadline scheduler,
* for the blk-mq scheduling framework
*
* Copyright (C) 2016 Jens Axboe <axboe@kernel.dk>
*/
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/blk-mq.h>
#include <linux/elevator.h>
#include <linux/bio.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/compiler.h>
#include <linux/rbtree.h>
#include <linux/sbitmap.h>
#include "blk.h"
#include "blk-mq.h"
#include "blk-mq-tag.h"
#include "blk-mq-sched.h"
/*
* See Documentation/block/deadline-iosched.txt
*/
static const int read_expire = HZ / 2; /* max time before a read is submitted. */
static const int write_expire = 5 * HZ; /* ditto for writes, these limits are SOFT! */
static const int writes_starved = 2; /* max times reads can starve a write */
static const int fifo_batch = 16; /* # of sequential requests treated as one
by the above parameters. For throughput. */
struct deadline_data {
/*
* run time data
*/
/*
* requests (deadline_rq s) are present on both sort_list and fifo_list
*/
struct rb_root sort_list[2];
struct list_head fifo_list[2];
/*
* next in sort order. read, write or both are NULL
*/
struct request *next_rq[2];
unsigned int batching; /* number of sequential requests made */
unsigned int starved; /* times reads have starved writes */
/*
* settings that change how the i/o scheduler behaves
*/
int fifo_expire[2];
int fifo_batch;
int writes_starved;
int front_merges;
spinlock_t lock;
struct list_head dispatch;
};
static inline struct rb_root *
deadline_rb_root(struct deadline_data *dd, struct request *rq)
{
return &dd->sort_list[rq_data_dir(rq)];
}
/*
* get the request after `rq' in sector-sorted order
*/
static inline struct request *
deadline_latter_request(struct request *rq)
{
struct rb_node *node = rb_next(&rq->rb_node);
if (node)
return rb_entry_rq(node);
return NULL;
}
static void
deadline_add_rq_rb(struct deadline_data *dd, struct request *rq)
{
struct rb_root *root = deadline_rb_root(dd, rq);
elv_rb_add(root, rq);
}
static inline void
deadline_del_rq_rb(struct deadline_data *dd, struct request *rq)
{
const int data_dir = rq_data_dir(rq);
if (dd->next_rq[data_dir] == rq)
dd->next_rq[data_dir] = deadline_latter_request(rq);
elv_rb_del(deadline_rb_root(dd, rq), rq);
}
/*
* remove rq from rbtree and fifo.
*/
static void deadline_remove_request(struct request_queue *q, struct request *rq)
{
struct deadline_data *dd = q->elevator->elevator_data;
list_del_init(&rq->queuelist);
/*
* We might not be on the rbtree, if we are doing an insert merge
*/
if (!RB_EMPTY_NODE(&rq->rb_node))
deadline_del_rq_rb(dd, rq);
elv_rqhash_del(q, rq);
if (q->last_merge == rq)
q->last_merge = NULL;
}
static void dd_request_merged(struct request_queue *q, struct request *req,
int type)
{
struct deadline_data *dd = q->elevator->elevator_data;
/*
* if the merge was a front merge, we need to reposition request
*/
if (type == ELEVATOR_FRONT_MERGE) {
elv_rb_del(deadline_rb_root(dd, req), req);
deadline_add_rq_rb(dd, req);
}
}
static void dd_merged_requests(struct request_queue *q, struct request *req,
struct request *next)
{
/*
* if next expires before rq, assign its expire time to rq
* and move into next position (next will be deleted) in fifo
*/
if (!list_empty(&req->queuelist) && !list_empty(&next->queuelist)) {
if (time_before((unsigned long)next->fifo_time,
(unsigned long)req->fifo_time)) {
list_move(&req->queuelist, &next->queuelist);
req->fifo_time = next->fifo_time;
}
}
/*
* kill knowledge of next, this one is a goner
*/
deadline_remove_request(q, next);
}
/*
* move an entry to dispatch queue
*/
static void
deadline_move_request(struct deadline_data *dd, struct request *rq)
{
const int data_dir = rq_data_dir(rq);
dd->next_rq[READ] = NULL;
dd->next_rq[WRITE] = NULL;
dd->next_rq[data_dir] = deadline_latter_request(rq);
/*
* take it off the sort and fifo list
*/
deadline_remove_request(rq->q, rq);
}
/*
* deadline_check_fifo returns 0 if there are no expired requests on the fifo,
* 1 otherwise. Requires !list_empty(&dd->fifo_list[data_dir])
*/
static inline int deadline_check_fifo(struct deadline_data *dd, int ddir)
{
struct request *rq = rq_entry_fifo(dd->fifo_list[ddir].next);
/*
* rq is expired!
*/
if (time_after_eq(jiffies, (unsigned long)rq->fifo_time))
return 1;
return 0;
}
/*
* deadline_dispatch_requests selects the best request according to
* read/write expire, fifo_batch, etc
*/
static struct request *__dd_dispatch_request(struct blk_mq_hw_ctx *hctx)
{
struct deadline_data *dd = hctx->queue->elevator->elevator_data;
struct request *rq;
bool reads, writes;
int data_dir;
if (!list_empty(&dd->dispatch)) {
rq = list_first_entry(&dd->dispatch, struct request, queuelist);
list_del_init(&rq->queuelist);
goto done;
}
reads = !list_empty(&dd->fifo_list[READ]);
writes = !list_empty(&dd->fifo_list[WRITE]);
/*
* batches are currently reads XOR writes
*/
if (dd->next_rq[WRITE])
rq = dd->next_rq[WRITE];
else
rq = dd->next_rq[READ];
if (rq && dd->batching < dd->fifo_batch)
/* we have a next request are still entitled to batch */
goto dispatch_request;
/*
* at this point we are not running a batch. select the appropriate
* data direction (read / write)
*/
if (reads) {
BUG_ON(RB_EMPTY_ROOT(&dd->sort_list[READ]));
if (writes && (dd->starved++ >= dd->writes_starved))
goto dispatch_writes;
data_dir = READ;
goto dispatch_find_request;
}
/*
* there are either no reads or writes have been starved
*/
if (writes) {
dispatch_writes:
BUG_ON(RB_EMPTY_ROOT(&dd->sort_list[WRITE]));
dd->starved = 0;
data_dir = WRITE;
goto dispatch_find_request;
}
return NULL;
dispatch_find_request:
/*
* we are not running a batch, find best request for selected data_dir
*/
if (deadline_check_fifo(dd, data_dir) || !dd->next_rq[data_dir]) {
/*
* A deadline has expired, the last request was in the other
* direction, or we have run out of higher-sectored requests.
* Start again from the request with the earliest expiry time.
*/
rq = rq_entry_fifo(dd->fifo_list[data_dir].next);
} else {
/*
* The last req was the same dir and we have a next request in
* sort order. No expired requests so continue on from here.
*/
rq = dd->next_rq[data_dir];
}
dd->batching = 0;
dispatch_request:
/*
* rq is the selected appropriate request.
*/
dd->batching++;
deadline_move_request(dd, rq);
done:
rq->rq_flags |= RQF_STARTED;
return rq;
}
static struct request *dd_dispatch_request(struct blk_mq_hw_ctx *hctx)
{
struct deadline_data *dd = hctx->queue->elevator->elevator_data;
struct request *rq;
spin_lock(&dd->lock);
rq = __dd_dispatch_request(hctx);
spin_unlock(&dd->lock);
return rq;
}
static void dd_exit_queue(struct elevator_queue *e)
{
struct deadline_data *dd = e->elevator_data;
BUG_ON(!list_empty(&dd->fifo_list[READ]));
BUG_ON(!list_empty(&dd->fifo_list[WRITE]));
kfree(dd);
}
/*
* initialize elevator private data (deadline_data).
*/
static int dd_init_queue(struct request_queue *q, struct elevator_type *e)
{
struct deadline_data *dd;
struct elevator_queue *eq;
eq = elevator_alloc(q, e);
if (!eq)
return -ENOMEM;
dd = kzalloc_node(sizeof(*dd), GFP_KERNEL, q->node);
if (!dd) {
kobject_put(&eq->kobj);
return -ENOMEM;
}
eq->elevator_data = dd;
INIT_LIST_HEAD(&dd->fifo_list[READ]);
INIT_LIST_HEAD(&dd->fifo_list[WRITE]);
dd->sort_list[READ] = RB_ROOT;
dd->sort_list[WRITE] = RB_ROOT;
dd->fifo_expire[READ] = read_expire;
dd->fifo_expire[WRITE] = write_expire;
dd->writes_starved = writes_starved;
dd->front_merges = 1;
dd->fifo_batch = fifo_batch;
spin_lock_init(&dd->lock);
INIT_LIST_HEAD(&dd->dispatch);
q->elevator = eq;
return 0;
}
static int dd_request_merge(struct request_queue *q, struct request **rq,
struct bio *bio)
{
struct deadline_data *dd = q->elevator->elevator_data;
sector_t sector = bio_end_sector(bio);
struct request *__rq;
if (!dd->front_merges)
return ELEVATOR_NO_MERGE;
__rq = elv_rb_find(&dd->sort_list[bio_data_dir(bio)], sector);
if (__rq) {
BUG_ON(sector != blk_rq_pos(__rq));
if (elv_bio_merge_ok(__rq, bio)) {
*rq = __rq;
return ELEVATOR_FRONT_MERGE;
}
}
return ELEVATOR_NO_MERGE;
}
static bool dd_bio_merge(struct blk_mq_hw_ctx *hctx, struct bio *bio)
{
struct request_queue *q = hctx->queue;
struct deadline_data *dd = q->elevator->elevator_data;
int ret;
spin_lock(&dd->lock);
ret = blk_mq_sched_try_merge(q, bio);
spin_unlock(&dd->lock);
return ret;
}
/*
* add rq to rbtree and fifo
*/
static void dd_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
bool at_head)
{
struct request_queue *q = hctx->queue;
struct deadline_data *dd = q->elevator->elevator_data;
const int data_dir = rq_data_dir(rq);
if (blk_mq_sched_try_insert_merge(q, rq))
return;
blk_mq_sched_request_inserted(rq);
if (blk_mq_sched_bypass_insert(hctx, rq))
return;
if (at_head || rq->cmd_type != REQ_TYPE_FS) {
if (at_head)
list_add(&rq->queuelist, &dd->dispatch);
else
list_add_tail(&rq->queuelist, &dd->dispatch);
} else {
deadline_add_rq_rb(dd, rq);
if (rq_mergeable(rq)) {
elv_rqhash_add(q, rq);
if (!q->last_merge)
q->last_merge = rq;
}
/*
* set expire time and add to fifo list
*/
rq->fifo_time = jiffies + dd->fifo_expire[data_dir];
list_add_tail(&rq->queuelist, &dd->fifo_list[data_dir]);
}
}
static void dd_insert_requests(struct blk_mq_hw_ctx *hctx,
struct list_head *list, bool at_head)
{
struct request_queue *q = hctx->queue;
struct deadline_data *dd = q->elevator->elevator_data;
spin_lock(&dd->lock);
while (!list_empty(list)) {
struct request *rq;
rq = list_first_entry(list, struct request, queuelist);
list_del_init(&rq->queuelist);
dd_insert_request(hctx, rq, at_head);
}
spin_unlock(&dd->lock);
}
static bool dd_has_work(struct blk_mq_hw_ctx *hctx)
{
struct deadline_data *dd = hctx->queue->elevator->elevator_data;
return !list_empty_careful(&dd->dispatch) ||
!list_empty_careful(&dd->fifo_list[0]) ||
!list_empty_careful(&dd->fifo_list[1]);
}
/*
* sysfs parts below
*/
static ssize_t
deadline_var_show(int var, char *page)
{
return sprintf(page, "%d\n", var);
}
static ssize_t
deadline_var_store(int *var, const char *page, size_t count)
{
char *p = (char *) page;
*var = simple_strtol(p, &p, 10);
return count;
}
#define SHOW_FUNCTION(__FUNC, __VAR, __CONV) \
static ssize_t __FUNC(struct elevator_queue *e, char *page) \
{ \
struct deadline_data *dd = e->elevator_data; \
int __data = __VAR; \
if (__CONV) \
__data = jiffies_to_msecs(__data); \
return deadline_var_show(__data, (page)); \
}
SHOW_FUNCTION(deadline_read_expire_show, dd->fifo_expire[READ], 1);
SHOW_FUNCTION(deadline_write_expire_show, dd->fifo_expire[WRITE], 1);
SHOW_FUNCTION(deadline_writes_starved_show, dd->writes_starved, 0);
SHOW_FUNCTION(deadline_front_merges_show, dd->front_merges, 0);
SHOW_FUNCTION(deadline_fifo_batch_show, dd->fifo_batch, 0);
#undef SHOW_FUNCTION
#define STORE_FUNCTION(__FUNC, __PTR, MIN, MAX, __CONV) \
static ssize_t __FUNC(struct elevator_queue *e, const char *page, size_t count) \
{ \
struct deadline_data *dd = e->elevator_data; \
int __data; \
int ret = deadline_var_store(&__data, (page), count); \
if (__data < (MIN)) \
__data = (MIN); \
else if (__data > (MAX)) \
__data = (MAX); \
if (__CONV) \
*(__PTR) = msecs_to_jiffies(__data); \
else \
*(__PTR) = __data; \
return ret; \
}
STORE_FUNCTION(deadline_read_expire_store, &dd->fifo_expire[READ], 0, INT_MAX, 1);
STORE_FUNCTION(deadline_write_expire_store, &dd->fifo_expire[WRITE], 0, INT_MAX, 1);
STORE_FUNCTION(deadline_writes_starved_store, &dd->writes_starved, INT_MIN, INT_MAX, 0);
STORE_FUNCTION(deadline_front_merges_store, &dd->front_merges, 0, 1, 0);
STORE_FUNCTION(deadline_fifo_batch_store, &dd->fifo_batch, 0, INT_MAX, 0);
#undef STORE_FUNCTION
#define DD_ATTR(name) \
__ATTR(name, S_IRUGO|S_IWUSR, deadline_##name##_show, \
deadline_##name##_store)
static struct elv_fs_entry deadline_attrs[] = {
DD_ATTR(read_expire),
DD_ATTR(write_expire),
DD_ATTR(writes_starved),
DD_ATTR(front_merges),
DD_ATTR(fifo_batch),
__ATTR_NULL
};
static struct elevator_type mq_deadline = {
.ops.mq = {
.insert_requests = dd_insert_requests,
.dispatch_request = dd_dispatch_request,
.next_request = elv_rb_latter_request,
.former_request = elv_rb_former_request,
.bio_merge = dd_bio_merge,
.request_merge = dd_request_merge,
.requests_merged = dd_merged_requests,
.request_merged = dd_request_merged,
.has_work = dd_has_work,
.init_sched = dd_init_queue,
.exit_sched = dd_exit_queue,
},
.uses_mq = true,
.elevator_attrs = deadline_attrs,
.elevator_name = "mq-deadline",
.elevator_owner = THIS_MODULE,
};
static int __init deadline_init(void)
{
return elv_register(&mq_deadline);
}
static void __exit deadline_exit(void)
{
elv_unregister(&mq_deadline);
}
module_init(deadline_init);
module_exit(deadline_exit);
MODULE_AUTHOR("Jens Axboe");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MQ deadline IO scheduler");

2
block/noop-iosched.c
View File

@ -92,7 +92,7 @@ static void noop_exit_queue(struct elevator_queue *e)
}
static struct elevator_type elevator_noop = {
.ops = {
.ops.sq = {
.elevator_merge_req_fn = noop_merged_requests,
.elevator_dispatch_fn = noop_dispatch,
.elevator_add_req_fn = noop_add_request,

17
block/partitions/efi.c
View File

@ -293,7 +293,7 @@ static gpt_entry *alloc_read_gpt_entries(struct parsed_partitions *state,
if (!gpt)
return NULL;
count = le32_to_cpu(gpt->num_partition_entries) *
count = (size_t)le32_to_cpu(gpt->num_partition_entries) *
le32_to_cpu(gpt->sizeof_partition_entry);
if (!count)
return NULL;
@ -352,7 +352,7 @@ static int is_gpt_valid(struct parsed_partitions *state, u64 lba,
gpt_header **gpt, gpt_entry **ptes)
{
u32 crc, origcrc;
u64 lastlba;
u64 lastlba, pt_size;
if (!ptes)
return 0;
@ -434,13 +434,20 @@ static int is_gpt_valid(struct parsed_partitions *state, u64 lba,
goto fail;
}
/* Sanity check partition table size */
pt_size = (u64)le32_to_cpu((*gpt)->num_partition_entries) *
le32_to_cpu((*gpt)->sizeof_partition_entry);
if (pt_size > KMALLOC_MAX_SIZE) {
pr_debug("GUID Partition Table is too large: %llu > %lu bytes\n",
(unsigned long long)pt_size, KMALLOC_MAX_SIZE);
goto fail;
}
if (!(*ptes = alloc_read_gpt_entries(state, *gpt)))
goto fail;
/* Check the GUID Partition Entry Array CRC */
crc = efi_crc32((const unsigned char *) (*ptes),
le32_to_cpu((*gpt)->num_partition_entries) *
le32_to_cpu((*gpt)->sizeof_partition_entry));
crc = efi_crc32((const unsigned char *) (*ptes), pt_size);
if (crc != le32_to_cpu((*gpt)->partition_entry_array_crc32)) {
pr_debug("GUID Partition Entry Array CRC check failed.\n");

2
drivers/block/floppy.c
View File

@ -3119,7 +3119,7 @@ static int raw_cmd_copyin(int cmd, void __user *param,
*rcmd = NULL;
loop:
ptr = kmalloc(sizeof(struct floppy_raw_cmd), GFP_USER);
ptr = kmalloc(sizeof(struct floppy_raw_cmd), GFP_KERNEL);
if (!ptr)
return -ENOMEM;
*rcmd = ptr;

2
drivers/md/bcache/request.c
View File

@ -666,7 +666,7 @@ static inline struct search *search_alloc(struct bio *bio,
s->iop.write_prio = 0;
s->iop.error = 0;
s->iop.flags = 0;
s->iop.flush_journal = (bio->bi_opf & (REQ_PREFLUSH|REQ_FUA)) != 0;
s->iop.flush_journal = op_is_flush(bio->bi_opf);
s->iop.wq = bcache_wq;
return s;

13
drivers/md/dm-cache-target.c
View File

@ -787,8 +787,7 @@ static void check_if_tick_bio_needed(struct cache *cache, struct bio *bio)
struct per_bio_data *pb = get_per_bio_data(bio, pb_data_size);
spin_lock_irqsave(&cache->lock, flags);
if (cache->need_tick_bio &&
!(bio->bi_opf & (REQ_FUA | REQ_PREFLUSH)) &&
if (cache->need_tick_bio && !op_is_flush(bio->bi_opf) &&
bio_op(bio) != REQ_OP_DISCARD) {
pb->tick = true;
cache->need_tick_bio = false;
@ -828,11 +827,6 @@ static dm_oblock_t get_bio_block(struct cache *cache, struct bio *bio)
return to_oblock(block_nr);
}
static int bio_triggers_commit(struct cache *cache, struct bio *bio)
{
return bio->bi_opf & (REQ_PREFLUSH | REQ_FUA);
}
/*
* You must increment the deferred set whilst the prison cell is held. To
* encourage this, we ask for 'cell' to be passed in.
@ -884,7 +878,7 @@ static void issue(struct cache *cache, struct bio *bio)
{
unsigned long flags;
if (!bio_triggers_commit(cache, bio)) {
if (!op_is_flush(bio->bi_opf)) {
accounted_request(cache, bio);
return;
}
@ -1069,8 +1063,7 @@ static void dec_io_migrations(struct cache *cache)
static bool discard_or_flush(struct bio *bio)
{
return bio_op(bio) == REQ_OP_DISCARD ||
bio->bi_opf & (REQ_PREFLUSH | REQ_FUA);
return bio_op(bio) == REQ_OP_DISCARD || op_is_flush(bio->bi_opf);
}
static void __cell_defer(struct cache *cache, struct dm_bio_prison_cell *cell)

13
drivers/md/dm-thin.c
View File

@ -699,7 +699,7 @@ static void remap_to_origin(struct thin_c *tc, struct bio *bio)
static int bio_triggers_commit(struct thin_c *tc, struct bio *bio)
{
return (bio->bi_opf & (REQ_PREFLUSH | REQ_FUA)) &&
return op_is_flush(bio->bi_opf) &&
dm_thin_changed_this_transaction(tc->td);
}
@ -870,8 +870,7 @@ static void __inc_remap_and_issue_cell(void *context,
struct bio *bio;
while ((bio = bio_list_pop(&cell->bios))) {
if (bio->bi_opf & (REQ_PREFLUSH | REQ_FUA) ||
bio_op(bio) == REQ_OP_DISCARD)
if (op_is_flush(bio->bi_opf) || bio_op(bio) == REQ_OP_DISCARD)
bio_list_add(&info->defer_bios, bio);
else {
inc_all_io_entry(info->tc->pool, bio);
@ -1716,9 +1715,8 @@ static void __remap_and_issue_shared_cell(void *context,
struct bio *bio;
while ((bio = bio_list_pop(&cell->bios))) {
if ((bio_data_dir(bio) == WRITE) ||
(bio->bi_opf & (REQ_PREFLUSH | REQ_FUA) ||
bio_op(bio) == REQ_OP_DISCARD))
if (bio_data_dir(bio) == WRITE || op_is_flush(bio->bi_opf) ||
bio_op(bio) == REQ_OP_DISCARD)
bio_list_add(&info->defer_bios, bio);
else {
struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));;
@ -2635,8 +2633,7 @@ static int thin_bio_map(struct dm_target *ti, struct bio *bio)
return DM_MAPIO_SUBMITTED;
}
if (bio->bi_opf & (REQ_PREFLUSH | REQ_FUA) ||
bio_op(bio) == REQ_OP_DISCARD) {
if (op_is_flush(bio->bi_opf) || bio_op(bio) == REQ_OP_DISCARD) {
thin_defer_bio_with_throttle(tc, bio);
return DM_MAPIO_SUBMITTED;
}

1
drivers/nvme/host/pci.c
View File

@ -1178,6 +1178,7 @@ static int nvme_alloc_admin_tags(struct nvme_dev *dev)
dev->admin_tagset.timeout = ADMIN_TIMEOUT;
dev->admin_tagset.numa_node = dev_to_node(dev->dev);
dev->admin_tagset.cmd_size = nvme_cmd_size(dev);
dev->admin_tagset.flags = BLK_MQ_F_NO_SCHED;
dev->admin_tagset.driver_data = dev;
if (blk_mq_alloc_tag_set(&dev->admin_tagset))

9
include/linux/blk-mq.h
View File

@ -22,6 +22,7 @@ struct blk_mq_hw_ctx {
unsigned long flags; /* BLK_MQ_F_* flags */
void *sched_data;
struct request_queue *queue;
struct blk_flush_queue *fq;
@ -35,6 +36,7 @@ struct blk_mq_hw_ctx {
atomic_t wait_index;
struct blk_mq_tags *tags;
struct blk_mq_tags *sched_tags;
struct srcu_struct queue_rq_srcu;
@ -60,7 +62,7 @@ struct blk_mq_hw_ctx {
struct blk_mq_tag_set {
unsigned int *mq_map;
struct blk_mq_ops *ops;
const struct blk_mq_ops *ops;
unsigned int nr_hw_queues;
unsigned int queue_depth; /* max hw supported */
unsigned int reserved_tags;
@ -151,11 +153,13 @@ enum {
BLK_MQ_F_SG_MERGE = 1 << 2,
BLK_MQ_F_DEFER_ISSUE = 1 << 4,
BLK_MQ_F_BLOCKING = 1 << 5,
BLK_MQ_F_NO_SCHED = 1 << 6,
BLK_MQ_F_ALLOC_POLICY_START_BIT = 8,
BLK_MQ_F_ALLOC_POLICY_BITS = 1,
BLK_MQ_S_STOPPED = 0,
BLK_MQ_S_TAG_ACTIVE = 1,
BLK_MQ_S_SCHED_RESTART = 2,
BLK_MQ_MAX_DEPTH = 10240,
@ -179,14 +183,13 @@ void blk_mq_free_tag_set(struct blk_mq_tag_set *set);
void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
void blk_mq_insert_request(struct request *, bool, bool, bool);
void blk_mq_free_request(struct request *rq);
void blk_mq_free_hctx_request(struct blk_mq_hw_ctx *, struct request *rq);
bool blk_mq_can_queue(struct blk_mq_hw_ctx *);
enum {
BLK_MQ_REQ_NOWAIT = (1 << 0), /* return when out of requests */
BLK_MQ_REQ_RESERVED = (1 << 1), /* allocate from reserved pool */
BLK_MQ_REQ_INTERNAL = (1 << 2), /* allocate internal/sched tag */
};
struct request *blk_mq_alloc_request(struct request_queue *q, int rw,

31
include/linux/blk_types.h
View File

@ -220,6 +220,15 @@ static inline bool op_is_write(unsigned int op)
return (op & 1);
}
/*
* Check if the bio or request is one that needs special treatment in the
* flush state machine.
*/
static inline bool op_is_flush(unsigned int op)
{
return op & (REQ_FUA | REQ_PREFLUSH);
}
/*
* Reads are always treated as synchronous, as are requests with the FUA or
* PREFLUSH flag. Other operations may be marked as synchronous using the
@ -232,22 +241,29 @@ static inline bool op_is_sync(unsigned int op)
}
typedef unsigned int blk_qc_t;
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
#define BLK_QC_T_NONE -1U
#define BLK_QC_T_SHIFT 16
#define BLK_QC_T_INTERNAL (1U << 31)
static inline bool blk_qc_t_valid(blk_qc_t cookie)
{
return cookie != BLK_QC_T_NONE;
}
static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num)
static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,
bool internal)
{
return tag | (queue_num << BLK_QC_T_SHIFT);
blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);
if (internal)
ret |= BLK_QC_T_INTERNAL;
return ret;
}
static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)
{
return cookie >> BLK_QC_T_SHIFT;
return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;
}
static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
@ -255,6 +271,11 @@ static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
return cookie & ((1u << BLK_QC_T_SHIFT) - 1);
}
static inline bool blk_qc_t_is_internal(blk_qc_t cookie)
{
return (cookie & BLK_QC_T_INTERNAL) != 0;
}
struct blk_issue_stat {
u64 time;
};

34
include/linux/blkdev.h
View File

@ -154,6 +154,7 @@ struct request {
/* the following two fields are internal, NEVER access directly */
unsigned int __data_len; /* total data len */
int tag;
sector_t __sector; /* sector cursor */
struct bio *bio;
@ -220,9 +221,10 @@ struct request {
unsigned short ioprio;
int internal_tag;
void *special; /* opaque pointer available for LLD use */
int tag;
int errors;
/*
@ -407,7 +409,7 @@ struct request_queue {
dma_drain_needed_fn *dma_drain_needed;
lld_busy_fn *lld_busy_fn;
struct blk_mq_ops *mq_ops;
const struct blk_mq_ops *mq_ops;
unsigned int *mq_map;
@ -569,6 +571,11 @@ struct request_queue {
struct list_head tag_set_list;
struct bio_set *bio_split;
#ifdef CONFIG_DEBUG_FS
struct dentry *debugfs_dir;
struct dentry *mq_debugfs_dir;
#endif
bool mq_sysfs_init_done;
};
@ -600,6 +607,7 @@ struct request_queue {
#define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */
#define QUEUE_FLAG_DAX 26 /* device supports DAX */
#define QUEUE_FLAG_STATS 27 /* track rq completion times */
#define QUEUE_FLAG_RESTART 28 /* queue needs restart at completion */
#define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
(1 << QUEUE_FLAG_STACKABLE) | \
@ -1620,6 +1628,25 @@ static inline bool bvec_gap_to_prev(struct request_queue *q,
return __bvec_gap_to_prev(q, bprv, offset);
}
/*
* Check if the two bvecs from two bios can be merged to one segment.
* If yes, no need to check gap between the two bios since the 1st bio
* and the 1st bvec in the 2nd bio can be handled in one segment.
*/
static inline bool bios_segs_mergeable(struct request_queue *q,
struct bio *prev, struct bio_vec *prev_last_bv,
struct bio_vec *next_first_bv)
{
if (!BIOVEC_PHYS_MERGEABLE(prev_last_bv, next_first_bv))
return false;
if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
return false;
if (prev->bi_seg_back_size + next_first_bv->bv_len >
queue_max_segment_size(q))
return false;
return true;
}
static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
struct bio *next)
{
@ -1629,7 +1656,8 @@ static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
bio_get_last_bvec(prev, &pb);
bio_get_first_bvec(next, &nb);
return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
if (!bios_segs_mergeable(q, prev, &pb, &nb))
return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
}
return false;

36
include/linux/elevator.h
View File

@ -77,6 +77,34 @@ struct elevator_ops
elevator_registered_fn *elevator_registered_fn;
};
struct blk_mq_alloc_data;
struct blk_mq_hw_ctx;
struct elevator_mq_ops {
int (*init_sched)(struct request_queue *, struct elevator_type *);
void (*exit_sched)(struct elevator_queue *);
bool (*allow_merge)(struct request_queue *, struct request *, struct bio *);
bool (*bio_merge)(struct blk_mq_hw_ctx *, struct bio *);
int (*request_merge)(struct request_queue *q, struct request **, struct bio *);
void (*request_merged)(struct request_queue *, struct request *, int);
void (*requests_merged)(struct request_queue *, struct request *, struct request *);
struct request *(*get_request)(struct request_queue *, unsigned int, struct blk_mq_alloc_data *);
void (*put_request)(struct request *);
void (*insert_requests)(struct blk_mq_hw_ctx *, struct list_head *, bool);
struct request *(*dispatch_request)(struct blk_mq_hw_ctx *);
bool (*has_work)(struct blk_mq_hw_ctx *);
void (*completed_request)(struct blk_mq_hw_ctx *, struct request *);
void (*started_request)(struct request *);
void (*requeue_request)(struct request *);
struct request *(*former_request)(struct request_queue *, struct request *);
struct request *(*next_request)(struct request_queue *, struct request *);
int (*get_rq_priv)(struct request_queue *, struct request *);
void (*put_rq_priv)(struct request_queue *, struct request *);
void (*init_icq)(struct io_cq *);
void (*exit_icq)(struct io_cq *);
};
#define ELV_NAME_MAX (16)
struct elv_fs_entry {
@ -94,12 +122,16 @@ struct elevator_type
struct kmem_cache *icq_cache;
/* fields provided by elevator implementation */
struct elevator_ops ops;
union {
struct elevator_ops sq;
struct elevator_mq_ops mq;
} ops;
size_t icq_size; /* see iocontext.h */
size_t icq_align; /* ditto */
struct elv_fs_entry *elevator_attrs;
char elevator_name[ELV_NAME_MAX];
struct module *elevator_owner;
bool uses_mq;
/* managed by elevator core */
char icq_cache_name[ELV_NAME_MAX + 5]; /* elvname + "_io_cq" */
@ -123,6 +155,7 @@ struct elevator_queue
struct kobject kobj;
struct mutex sysfs_lock;
unsigned int registered:1;
unsigned int uses_mq:1;
DECLARE_HASHTABLE(hash, ELV_HASH_BITS);
};
@ -139,6 +172,7 @@ extern void elv_merge_requests(struct request_queue *, struct request *,
extern void elv_merged_request(struct request_queue *, struct request *, int);
extern void elv_bio_merged(struct request_queue *q, struct request *,
struct bio *);
extern bool elv_attempt_insert_merge(struct request_queue *, struct request *);
extern void elv_requeue_request(struct request_queue *, struct request *);
extern struct request *elv_former_request(struct request_queue *, struct request *);
extern struct request *elv_latter_request(struct request_queue *, struct request *);

30
include/linux/sbitmap.h
View File

@ -258,6 +258,26 @@ static inline int sbitmap_test_bit(struct sbitmap *sb, unsigned int bitnr)
unsigned int sbitmap_weight(const struct sbitmap *sb);
/**
* sbitmap_show() - Dump &struct sbitmap information to a &struct seq_file.
* @sb: Bitmap to show.
* @m: struct seq_file to write to.
*
* This is intended for debugging. The format may change at any time.
*/
void sbitmap_show(struct sbitmap *sb, struct seq_file *m);
/**
* sbitmap_bitmap_show() - Write a hex dump of a &struct sbitmap to a &struct
* seq_file.
* @sb: Bitmap to show.
* @m: struct seq_file to write to.
*
* This is intended for debugging. The output isn't guaranteed to be internally
* consistent.
*/
void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m);
/**
* sbitmap_queue_init_node() - Initialize a &struct sbitmap_queue on a specific
* memory node.
@ -370,4 +390,14 @@ static inline struct sbq_wait_state *sbq_wait_ptr(struct sbitmap_queue *sbq,
*/
void sbitmap_queue_wake_all(struct sbitmap_queue *sbq);
/**
* sbitmap_queue_show() - Dump &struct sbitmap_queue information to a &struct
* seq_file.
* @sbq: Bitmap queue to show.
* @m: struct seq_file to write to.
*
* This is intended for debugging. The format may change at any time.
*/
void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m);
#endif /* __LINUX_SCALE_BITMAP_H */

139
lib/sbitmap.c
View File

@ -17,6 +17,7 @@
#include <linux/random.h>
#include <linux/sbitmap.h>
#include <linux/seq_file.h>
int sbitmap_init_node(struct sbitmap *sb, unsigned int depth, int shift,
gfp_t flags, int node)
@ -180,6 +181,62 @@ unsigned int sbitmap_weight(const struct sbitmap *sb)
}
EXPORT_SYMBOL_GPL(sbitmap_weight);
void sbitmap_show(struct sbitmap *sb, struct seq_file *m)
{
seq_printf(m, "depth=%u\n", sb->depth);
seq_printf(m, "busy=%u\n", sbitmap_weight(sb));
seq_printf(m, "bits_per_word=%u\n", 1U << sb->shift);
seq_printf(m, "map_nr=%u\n", sb->map_nr);
}
EXPORT_SYMBOL_GPL(sbitmap_show);
static inline void emit_byte(struct seq_file *m, unsigned int offset, u8 byte)
{
if ((offset & 0xf) == 0) {
if (offset != 0)
seq_putc(m, '\n');
seq_printf(m, "%08x:", offset);
}
if ((offset & 0x1) == 0)
seq_putc(m, ' ');
seq_printf(m, "%02x", byte);
}
void sbitmap_bitmap_show(struct sbitmap *sb, struct seq_file *m)
{
u8 byte = 0;
unsigned int byte_bits = 0;
unsigned int offset = 0;
int i;
for (i = 0; i < sb->map_nr; i++) {
unsigned long word = READ_ONCE(sb->map[i].word);
unsigned int word_bits = READ_ONCE(sb->map[i].depth);
while (word_bits > 0) {
unsigned int bits = min(8 - byte_bits, word_bits);
byte |= (word & (BIT(bits) - 1)) << byte_bits;
byte_bits += bits;
if (byte_bits == 8) {
emit_byte(m, offset, byte);
byte = 0;
byte_bits = 0;
offset++;
}
word >>= bits;
word_bits -= bits;
}
}
if (byte_bits) {
emit_byte(m, offset, byte);
offset++;
}
if (offset)
seq_putc(m, '\n');
}
EXPORT_SYMBOL_GPL(sbitmap_bitmap_show);
static unsigned int sbq_calc_wake_batch(unsigned int depth)
{
unsigned int wake_batch;
@ -239,7 +296,19 @@ EXPORT_SYMBOL_GPL(sbitmap_queue_init_node);
void sbitmap_queue_resize(struct sbitmap_queue *sbq, unsigned int depth)
{
sbq->wake_batch = sbq_calc_wake_batch(depth);
unsigned int wake_batch = sbq_calc_wake_batch(depth);
int i;
if (sbq->wake_batch != wake_batch) {
WRITE_ONCE(sbq->wake_batch, wake_batch);
/*
* Pairs with the memory barrier in sbq_wake_up() to ensure that
* the batch size is updated before the wait counts.
*/
smp_mb__before_atomic();
for (i = 0; i < SBQ_WAIT_QUEUES; i++)
atomic_set(&sbq->ws[i].wait_cnt, 1);
}
sbitmap_resize(&sbq->sb, depth);
}
EXPORT_SYMBOL_GPL(sbitmap_queue_resize);
@ -297,20 +366,39 @@ static struct sbq_wait_state *sbq_wake_ptr(struct sbitmap_queue *sbq)
static void sbq_wake_up(struct sbitmap_queue *sbq)
{
struct sbq_wait_state *ws;
unsigned int wake_batch;
int wait_cnt;
/* Ensure that the wait list checks occur after clear_bit(). */
smp_mb();
/*
* Pairs with the memory barrier in set_current_state() to ensure the
* proper ordering of clear_bit()/waitqueue_active() in the waker and
* test_and_set_bit()/prepare_to_wait()/finish_wait() in the waiter. See
* the comment on waitqueue_active(). This is __after_atomic because we
* just did clear_bit() in the caller.
*/
smp_mb__after_atomic();
ws = sbq_wake_ptr(sbq);
if (!ws)
return;
wait_cnt = atomic_dec_return(&ws->wait_cnt);
if (unlikely(wait_cnt < 0))
wait_cnt = atomic_inc_return(&ws->wait_cnt);
if (wait_cnt == 0) {
atomic_add(sbq->wake_batch, &ws->wait_cnt);
if (wait_cnt <= 0) {
wake_batch = READ_ONCE(sbq->wake_batch);
/*
* Pairs with the memory barrier in sbitmap_queue_resize() to
* ensure that we see the batch size update before the wait
* count is reset.
*/
smp_mb__before_atomic();
/*
* If there are concurrent callers to sbq_wake_up(), the last
* one to decrement the wait count below zero will bump it back
* up. If there is a concurrent resize, the count reset will
* either cause the cmpxchg to fail or overwrite after the
* cmpxchg.
*/
atomic_cmpxchg(&ws->wait_cnt, wait_cnt, wait_cnt + wake_batch);
sbq_index_atomic_inc(&sbq->wake_index);
wake_up(&ws->wait);
}
@ -331,7 +419,8 @@ void sbitmap_queue_wake_all(struct sbitmap_queue *sbq)
int i, wake_index;
/*
* Make sure all changes prior to this are visible from other CPUs.
* Pairs with the memory barrier in set_current_state() like in
* sbq_wake_up().
*/
smp_mb();
wake_index = atomic_read(&sbq->wake_index);
@ -345,3 +434,37 @@ void sbitmap_queue_wake_all(struct sbitmap_queue *sbq)
}
}
EXPORT_SYMBOL_GPL(sbitmap_queue_wake_all);
void sbitmap_queue_show(struct sbitmap_queue *sbq, struct seq_file *m)
{
bool first;
int i;
sbitmap_show(&sbq->sb, m);
seq_puts(m, "alloc_hint={");
first = true;
for_each_possible_cpu(i) {
if (!first)
seq_puts(m, ", ");
first = false;
seq_printf(m, "%u", *per_cpu_ptr(sbq->alloc_hint, i));
}
seq_puts(m, "}\n");
seq_printf(m, "wake_batch=%u\n", sbq->wake_batch);
seq_printf(m, "wake_index=%d\n", atomic_read(&sbq->wake_index));
seq_puts(m, "ws={\n");
for (i = 0; i < SBQ_WAIT_QUEUES; i++) {
struct sbq_wait_state *ws = &sbq->ws[i];
seq_printf(m, "\t{.wait_cnt=%d, .wait=%s},\n",
atomic_read(&ws->wait_cnt),
waitqueue_active(&ws->wait) ? "active" : "inactive");
}
seq_puts(m, "}\n");
seq_printf(m, "round_robin=%d\n", sbq->round_robin);
}
EXPORT_SYMBOL_GPL(sbitmap_queue_show);