ptp: add debugfs interface to see applied channel masks

Use debugfs to be able to view channel mask applied to every timestamp
event queue.

Every time the device is opened, a new entry is created in
`$DEBUGFS_MOUNTPOINT/ptpN/$INSTANCE_ADDRESS/mask`.

The mask value can be viewed grouped in 32bit decimal values using cat,
or converted to hexadecimal with the included `ptpchmaskfmt.sh` script.
32 bit values are listed from least significant to most significant.

Signed-off-by: Xabier Marquiegui <reibax@gmail.com>
Suggested-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Xabier Marquiegui 2023-10-12 00:39:57 +02:00 committed by David S. Miller
parent c5a445b1e9
commit 403376ddb4
4 changed files with 39 additions and 0 deletions

View File

@ -10,6 +10,7 @@
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/timekeeping.h>
#include <linux/debugfs.h>
#include <linux/nospec.h>
@ -106,6 +107,7 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
struct ptp_clock *ptp =
container_of(pccontext->clk, struct ptp_clock, clock);
struct timestamp_event_queue *queue;
char debugfsname[32];
queue = kzalloc(sizeof(*queue), GFP_KERNEL);
if (!queue)
@ -119,6 +121,17 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode)
spin_lock_init(&queue->lock);
list_add_tail(&queue->qlist, &ptp->tsevqs);
pccontext->private_clkdata = queue;
/* Debugfs contents */
sprintf(debugfsname, "0x%p", queue);
queue->debugfs_instance =
debugfs_create_dir(debugfsname, ptp->debugfs_root);
queue->dfs_bitmap.array = (u32 *)queue->mask;
queue->dfs_bitmap.n_elements =
DIV_ROUND_UP(PTP_MAX_CHANNELS, BITS_PER_BYTE * sizeof(u32));
debugfs_create_u32_array("mask", 0444, queue->debugfs_instance,
&queue->dfs_bitmap);
return 0;
}
@ -128,6 +141,7 @@ int ptp_release(struct posix_clock_context *pccontext)
unsigned long flags;
if (queue) {
debugfs_remove(queue->debugfs_instance);
pccontext->private_clkdata = NULL;
spin_lock_irqsave(&queue->lock, flags);
list_del(&queue->qlist);

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@ -15,6 +15,7 @@
#include <linux/slab.h>
#include <linux/syscalls.h>
#include <linux/uaccess.h>
#include <linux/debugfs.h>
#include <uapi/linux/sched/types.h>
#include "ptp_private.h"
@ -185,6 +186,7 @@ static void ptp_clock_release(struct device *dev)
spin_unlock_irqrestore(&tsevq->lock, flags);
bitmap_free(tsevq->mask);
kfree(tsevq);
debugfs_remove(ptp->debugfs_root);
ida_free(&ptp_clocks_map, ptp->index);
kfree(ptp);
}
@ -218,6 +220,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
struct ptp_clock *ptp;
struct timestamp_event_queue *queue = NULL;
int err = 0, index, major = MAJOR(ptp_devt);
char debugfsname[8];
size_t size;
if (info->n_alarm > PTP_MAX_ALARMS)
@ -339,6 +342,10 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
return ERR_PTR(err);
}
/* Debugfs initialization */
sprintf(debugfsname, "ptp%d", ptp->index);
ptp->debugfs_root = debugfs_create_dir(debugfsname, NULL);
return ptp;
no_pps:

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@ -17,6 +17,7 @@
#include <linux/time.h>
#include <linux/list.h>
#include <linux/bitmap.h>
#include <linux/debugfs.h>
#define PTP_MAX_TIMESTAMPS 128
#define PTP_BUF_TIMESTAMPS 30
@ -30,6 +31,8 @@ struct timestamp_event_queue {
spinlock_t lock;
struct list_head qlist;
unsigned long *mask;
struct dentry *debugfs_instance;
struct debugfs_u32_array dfs_bitmap;
};
struct ptp_clock {
@ -57,6 +60,7 @@ struct ptp_clock {
struct mutex n_vclocks_mux; /* protect concurrent n_vclocks access */
bool is_virtual_clock;
bool has_cycles;
struct dentry *debugfs_root;
};
#define info_to_vclock(d) container_of((d), struct ptp_vclock, info)

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@ -0,0 +1,14 @@
#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
# Simple helper script to transform ptp debugfs timestamp event queue filtering
# masks from decimal values to hexadecimal values
# Only takes the debugfs mask file path as an argument
DEBUGFS_MASKFILE="${1}"
#shellcheck disable=SC2013,SC2086
for int in $(cat "$DEBUGFS_MASKFILE") ; do
printf '0x%08X ' "$int"
done
echo