https://github.com/torvalds/linux
Tip revision: 4495c08e84729385774601b5146d51d9e5849f81 authored by Linus Torvalds on 12 March 2017, 21:47:08 UTC
Linux 4.11-rc2
Linux 4.11-rc2
Tip revision: 4495c08
blk-mq-debugfs.c
/*
* 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.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 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_flags=0x%x, .rq_flags=0x%x, .tag=%d, .internal_tag=%d}\n",
rq, rq->cmd_flags, (__force unsigned int)rq->rq_flags,
rq->tag, rq->internal_tag);
return 0;
}
static void *hctx_dispatch_start(struct seq_file *m, loff_t *pos)
__acquires(&hctx->lock)
{
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)
__releases(&hctx->lock)
{
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;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->tags)
blk_mq_debugfs_tags_show(m, hctx->tags);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
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;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->tags)
sbitmap_bitmap_show(&hctx->tags->bitmap_tags.sb, m);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
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;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->sched_tags)
blk_mq_debugfs_tags_show(m, hctx->sched_tags);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
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;
int res;
res = mutex_lock_interruptible(&q->sysfs_lock);
if (res)
goto out;
if (hctx->sched_tags)
sbitmap_bitmap_show(&hctx->sched_tags->bitmap_tags.sb, m);
mutex_unlock(&q->sysfs_lock);
out:
return res;
}
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)
__acquires(&ctx->lock)
{
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)
__releases(&ctx->lock)
{
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 (!blk_debugfs_root)
return -ENOENT;
q->debugfs_dir = debugfs_create_dir(name, blk_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 bool debugfs_create_files(struct dentry *parent, void *data,
const struct blk_mq_debugfs_attr *attr)
{
for (; attr->name; attr++) {
if (!debugfs_create_file(attr->name, attr->mode, parent,
data, attr->fops))
return false;
}
return true;
}
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];
snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
ctx_dir = debugfs_create_dir(name, hctx_dir);
if (!ctx_dir)
return -ENOMEM;
if (!debugfs_create_files(ctx_dir, ctx, blk_mq_debugfs_ctx_attrs))
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;
if (!debugfs_create_files(hctx_dir, hctx, blk_mq_debugfs_hctx_attrs))
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;
}