linux/block/blk-mq-debugfs.c

1003 lines
24 KiB
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-debugfs.h"
#include "blk-mq-tag.h"
static void print_stat(struct seq_file *m, struct blk_rq_stat *stat)
{
if (stat->nr_samples) {
seq_printf(m, "samples=%d, mean=%lld, min=%llu, max=%llu",
stat->nr_samples, stat->mean, stat->min, stat->max);
} else {
seq_puts(m, "samples=0");
}
}
static int queue_poll_stat_show(void *data, struct seq_file *m)
{
struct request_queue *q = data;
int bucket;
for (bucket = 0; bucket < BLK_MQ_POLL_STATS_BKTS/2; bucket++) {
seq_printf(m, "read (%d Bytes): ", 1 << (9+bucket));
print_stat(m, &q->poll_stat[2*bucket]);
seq_puts(m, "\n");
seq_printf(m, "write (%d Bytes): ", 1 << (9+bucket));
print_stat(m, &q->poll_stat[2*bucket+1]);
seq_puts(m, "\n");
}
return 0;
}
static void *queue_requeue_list_start(struct seq_file *m, loff_t *pos)
__acquires(&q->requeue_lock)
{
struct request_queue *q = m->private;
spin_lock_irq(&q->requeue_lock);
return seq_list_start(&q->requeue_list, *pos);
}
static void *queue_requeue_list_next(struct seq_file *m, void *v, loff_t *pos)
{
struct request_queue *q = m->private;
return seq_list_next(v, &q->requeue_list, pos);
}
static void queue_requeue_list_stop(struct seq_file *m, void *v)
__releases(&q->requeue_lock)
{
struct request_queue *q = m->private;
spin_unlock_irq(&q->requeue_lock);
}
static const struct seq_operations queue_requeue_list_seq_ops = {
.start = queue_requeue_list_start,
.next = queue_requeue_list_next,
.stop = queue_requeue_list_stop,
.show = blk_mq_debugfs_rq_show,
};
static int blk_flags_show(struct seq_file *m, const unsigned long flags,
const char *const *flag_name, int flag_name_count)
{
bool sep = false;
int i;
for (i = 0; i < sizeof(flags) * BITS_PER_BYTE; i++) {
if (!(flags & BIT(i)))
continue;
if (sep)
seq_puts(m, "|");
sep = true;
if (i < flag_name_count && flag_name[i])
seq_puts(m, flag_name[i]);
else
seq_printf(m, "%d", i);
}
return 0;
}
#define QUEUE_FLAG_NAME(name) [QUEUE_FLAG_##name] = #name
static const char *const blk_queue_flag_name[] = {
QUEUE_FLAG_NAME(QUEUED),
QUEUE_FLAG_NAME(STOPPED),
QUEUE_FLAG_NAME(DYING),
QUEUE_FLAG_NAME(BYPASS),
QUEUE_FLAG_NAME(BIDI),
QUEUE_FLAG_NAME(NOMERGES),
QUEUE_FLAG_NAME(SAME_COMP),
QUEUE_FLAG_NAME(FAIL_IO),
QUEUE_FLAG_NAME(NONROT),
QUEUE_FLAG_NAME(IO_STAT),
QUEUE_FLAG_NAME(DISCARD),
QUEUE_FLAG_NAME(NOXMERGES),
QUEUE_FLAG_NAME(ADD_RANDOM),
QUEUE_FLAG_NAME(SECERASE),
QUEUE_FLAG_NAME(SAME_FORCE),
QUEUE_FLAG_NAME(DEAD),
QUEUE_FLAG_NAME(INIT_DONE),
QUEUE_FLAG_NAME(NO_SG_MERGE),
QUEUE_FLAG_NAME(POLL),
QUEUE_FLAG_NAME(WC),
QUEUE_FLAG_NAME(FUA),
QUEUE_FLAG_NAME(FLUSH_NQ),
QUEUE_FLAG_NAME(DAX),
QUEUE_FLAG_NAME(STATS),
QUEUE_FLAG_NAME(POLL_STATS),
QUEUE_FLAG_NAME(REGISTERED),
QUEUE_FLAG_NAME(SCSI_PASSTHROUGH),
QUEUE_FLAG_NAME(QUIESCED),
QUEUE_FLAG_NAME(PREEMPT_ONLY),
};
#undef QUEUE_FLAG_NAME
static int queue_state_show(void *data, struct seq_file *m)
{
struct request_queue *q = data;
blk_flags_show(m, q->queue_flags, blk_queue_flag_name,
ARRAY_SIZE(blk_queue_flag_name));
seq_puts(m, "\n");
return 0;
}
static ssize_t queue_state_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct request_queue *q = data;
char opbuf[16] = { }, *op;
/*
* The "state" attribute is removed after blk_cleanup_queue() has called
* blk_mq_free_queue(). Return if QUEUE_FLAG_DEAD has been set to avoid
* triggering a use-after-free.
*/
if (blk_queue_dead(q))
return -ENOENT;
if (count >= sizeof(opbuf)) {
pr_err("%s: operation too long\n", __func__);
goto inval;
}
if (copy_from_user(opbuf, buf, count))
return -EFAULT;
op = strstrip(opbuf);
if (strcmp(op, "run") == 0) {
blk_mq_run_hw_queues(q, true);
} else if (strcmp(op, "start") == 0) {
blk_mq_start_stopped_hw_queues(q, true);
} else if (strcmp(op, "kick") == 0) {
blk_mq_kick_requeue_list(q);
} else {
pr_err("%s: unsupported operation '%s'\n", __func__, op);
inval:
pr_err("%s: use 'run', 'start' or 'kick'\n", __func__);
return -EINVAL;
}
return count;
}
static int queue_write_hint_show(void *data, struct seq_file *m)
{
struct request_queue *q = data;
int i;
for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
seq_printf(m, "hint%d: %llu\n", i, q->write_hints[i]);
return 0;
}
static ssize_t queue_write_hint_store(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct request_queue *q = data;
int i;
for (i = 0; i < BLK_MAX_WRITE_HINTS; i++)
q->write_hints[i] = 0;
return count;
}
static const struct blk_mq_debugfs_attr blk_mq_debugfs_queue_attrs[] = {
{ "poll_stat", 0400, queue_poll_stat_show },
{ "requeue_list", 0400, .seq_ops = &queue_requeue_list_seq_ops },
{ "state", 0600, queue_state_show, queue_state_write },
{ "write_hints", 0600, queue_write_hint_show, queue_write_hint_store },
{ "zone_wlock", 0400, queue_zone_wlock_show, NULL },
{ },
};
#define HCTX_STATE_NAME(name) [BLK_MQ_S_##name] = #name
static const char *const hctx_state_name[] = {
HCTX_STATE_NAME(STOPPED),
HCTX_STATE_NAME(TAG_ACTIVE),
HCTX_STATE_NAME(SCHED_RESTART),
};
#undef HCTX_STATE_NAME
static int hctx_state_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
blk_flags_show(m, hctx->state, hctx_state_name,
ARRAY_SIZE(hctx_state_name));
seq_puts(m, "\n");
return 0;
}
#define BLK_TAG_ALLOC_NAME(name) [BLK_TAG_ALLOC_##name] = #name
static const char *const alloc_policy_name[] = {
BLK_TAG_ALLOC_NAME(FIFO),
BLK_TAG_ALLOC_NAME(RR),
};
#undef BLK_TAG_ALLOC_NAME
#define HCTX_FLAG_NAME(name) [ilog2(BLK_MQ_F_##name)] = #name
static const char *const hctx_flag_name[] = {
HCTX_FLAG_NAME(SHOULD_MERGE),
HCTX_FLAG_NAME(TAG_SHARED),
HCTX_FLAG_NAME(SG_MERGE),
HCTX_FLAG_NAME(BLOCKING),
HCTX_FLAG_NAME(NO_SCHED),
};
#undef HCTX_FLAG_NAME
static int hctx_flags_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
const int alloc_policy = BLK_MQ_FLAG_TO_ALLOC_POLICY(hctx->flags);
seq_puts(m, "alloc_policy=");
if (alloc_policy < ARRAY_SIZE(alloc_policy_name) &&
alloc_policy_name[alloc_policy])
seq_puts(m, alloc_policy_name[alloc_policy]);
else
seq_printf(m, "%d", alloc_policy);
seq_puts(m, " ");
blk_flags_show(m,
hctx->flags ^ BLK_ALLOC_POLICY_TO_MQ_FLAG(alloc_policy),
hctx_flag_name, ARRAY_SIZE(hctx_flag_name));
seq_puts(m, "\n");
return 0;
}
#define REQ_OP_NAME(name) [REQ_OP_##name] = #name
static const char *const op_name[] = {
REQ_OP_NAME(READ),
REQ_OP_NAME(WRITE),
REQ_OP_NAME(FLUSH),
REQ_OP_NAME(DISCARD),
REQ_OP_NAME(ZONE_REPORT),
REQ_OP_NAME(SECURE_ERASE),
REQ_OP_NAME(ZONE_RESET),
REQ_OP_NAME(WRITE_SAME),
REQ_OP_NAME(WRITE_ZEROES),
REQ_OP_NAME(SCSI_IN),
REQ_OP_NAME(SCSI_OUT),
REQ_OP_NAME(DRV_IN),
REQ_OP_NAME(DRV_OUT),
};
#undef REQ_OP_NAME
#define CMD_FLAG_NAME(name) [__REQ_##name] = #name
static const char *const cmd_flag_name[] = {
CMD_FLAG_NAME(FAILFAST_DEV),
CMD_FLAG_NAME(FAILFAST_TRANSPORT),
CMD_FLAG_NAME(FAILFAST_DRIVER),
CMD_FLAG_NAME(SYNC),
CMD_FLAG_NAME(META),
CMD_FLAG_NAME(PRIO),
CMD_FLAG_NAME(NOMERGE),
CMD_FLAG_NAME(IDLE),
CMD_FLAG_NAME(INTEGRITY),
CMD_FLAG_NAME(FUA),
CMD_FLAG_NAME(PREFLUSH),
CMD_FLAG_NAME(RAHEAD),
CMD_FLAG_NAME(BACKGROUND),
CMD_FLAG_NAME(NOUNMAP),
CMD_FLAG_NAME(NOWAIT),
};
#undef CMD_FLAG_NAME
#define RQF_NAME(name) [ilog2((__force u32)RQF_##name)] = #name
static const char *const rqf_name[] = {
RQF_NAME(SORTED),
RQF_NAME(STARTED),
RQF_NAME(QUEUED),
RQF_NAME(SOFTBARRIER),
RQF_NAME(FLUSH_SEQ),
RQF_NAME(MIXED_MERGE),
RQF_NAME(MQ_INFLIGHT),
RQF_NAME(DONTPREP),
RQF_NAME(PREEMPT),
RQF_NAME(COPY_USER),
RQF_NAME(FAILED),
RQF_NAME(QUIET),
RQF_NAME(ELVPRIV),
RQF_NAME(IO_STAT),
RQF_NAME(ALLOCED),
RQF_NAME(PM),
RQF_NAME(HASHED),
RQF_NAME(STATS),
RQF_NAME(SPECIAL_PAYLOAD),
RQF_NAME(ZONE_WRITE_LOCKED),
RQF_NAME(MQ_POLL_SLEPT),
};
#undef RQF_NAME
static const char *const blk_mq_rq_state_name_array[] = {
[MQ_RQ_IDLE] = "idle",
[MQ_RQ_IN_FLIGHT] = "in_flight",
[MQ_RQ_COMPLETE] = "complete",
};
static const char *blk_mq_rq_state_name(enum mq_rq_state rq_state)
{
if (WARN_ON_ONCE((unsigned int)rq_state >=
ARRAY_SIZE(blk_mq_rq_state_name_array)))
return "(?)";
return blk_mq_rq_state_name_array[rq_state];
}
int __blk_mq_debugfs_rq_show(struct seq_file *m, struct request *rq)
{
const struct blk_mq_ops *const mq_ops = rq->q->mq_ops;
const unsigned int op = rq->cmd_flags & REQ_OP_MASK;
seq_printf(m, "%p {.op=", rq);
if (op < ARRAY_SIZE(op_name) && op_name[op])
seq_printf(m, "%s", op_name[op]);
else
seq_printf(m, "%d", op);
seq_puts(m, ", .cmd_flags=");
blk_flags_show(m, rq->cmd_flags & ~REQ_OP_MASK, cmd_flag_name,
ARRAY_SIZE(cmd_flag_name));
seq_puts(m, ", .rq_flags=");
blk_flags_show(m, (__force unsigned int)rq->rq_flags, rqf_name,
ARRAY_SIZE(rqf_name));
seq_printf(m, ", .state=%s", blk_mq_rq_state_name(blk_mq_rq_state(rq)));
seq_printf(m, ", .tag=%d, .internal_tag=%d", rq->tag,
rq->internal_tag);
if (mq_ops->show_rq)
mq_ops->show_rq(m, rq);
seq_puts(m, "}\n");
return 0;
}
EXPORT_SYMBOL_GPL(__blk_mq_debugfs_rq_show);
int blk_mq_debugfs_rq_show(struct seq_file *m, void *v)
{
return __blk_mq_debugfs_rq_show(m, list_entry_rq(v));
}
EXPORT_SYMBOL_GPL(blk_mq_debugfs_rq_show);
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,
};
struct show_busy_params {
struct seq_file *m;
struct blk_mq_hw_ctx *hctx;
};
/*
* Note: the state of a request may change while this function is in progress,
* e.g. due to a concurrent blk_mq_finish_request() call.
*/
static void hctx_show_busy_rq(struct request *rq, void *data, bool reserved)
{
const struct show_busy_params *params = data;
if (blk_mq_map_queue(rq->q, rq->mq_ctx->cpu) == params->hctx &&
blk_mq_rq_state(rq) != MQ_RQ_IDLE)
__blk_mq_debugfs_rq_show(params->m,
list_entry_rq(&rq->queuelist));
}
static int hctx_busy_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
struct show_busy_params params = { .m = m, .hctx = hctx };
blk_mq_tagset_busy_iter(hctx->queue->tag_set, hctx_show_busy_rq,
&params);
return 0;
}
static int hctx_ctx_map_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
sbitmap_bitmap_show(&hctx->ctx_map, m);
return 0;
}
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(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
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_bitmap_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
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_sched_tags_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
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_bitmap_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
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_io_poll_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
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 ssize_t hctx_io_poll_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
hctx->poll_considered = hctx->poll_invoked = hctx->poll_success = 0;
return count;
}
static int hctx_dispatched_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
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 ssize_t hctx_dispatched_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
int i;
for (i = 0; i < BLK_MQ_MAX_DISPATCH_ORDER; i++)
hctx->dispatched[i] = 0;
return count;
}
static int hctx_queued_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%lu\n", hctx->queued);
return 0;
}
static ssize_t hctx_queued_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
hctx->queued = 0;
return count;
}
static int hctx_run_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%lu\n", hctx->run);
return 0;
}
static ssize_t hctx_run_write(void *data, const char __user *buf, size_t count,
loff_t *ppos)
{
struct blk_mq_hw_ctx *hctx = data;
hctx->run = 0;
return count;
}
static int hctx_active_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%d\n", atomic_read(&hctx->nr_active));
return 0;
}
static int hctx_dispatch_busy_show(void *data, struct seq_file *m)
{
struct blk_mq_hw_ctx *hctx = data;
seq_printf(m, "%u\n", hctx->dispatch_busy);
return 0;
}
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_dispatched_show(void *data, struct seq_file *m)
{
struct blk_mq_ctx *ctx = data;
seq_printf(m, "%lu %lu\n", ctx->rq_dispatched[1], ctx->rq_dispatched[0]);
return 0;
}
static ssize_t ctx_dispatched_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_ctx *ctx = data;
ctx->rq_dispatched[0] = ctx->rq_dispatched[1] = 0;
return count;
}
static int ctx_merged_show(void *data, struct seq_file *m)
{
struct blk_mq_ctx *ctx = data;
seq_printf(m, "%lu\n", ctx->rq_merged);
return 0;
}
static ssize_t ctx_merged_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_ctx *ctx = data;
ctx->rq_merged = 0;
return count;
}
static int ctx_completed_show(void *data, struct seq_file *m)
{
struct blk_mq_ctx *ctx = data;
seq_printf(m, "%lu %lu\n", ctx->rq_completed[1], ctx->rq_completed[0]);
return 0;
}
static ssize_t ctx_completed_write(void *data, const char __user *buf,
size_t count, loff_t *ppos)
{
struct blk_mq_ctx *ctx = data;
ctx->rq_completed[0] = ctx->rq_completed[1] = 0;
return count;
}
static int blk_mq_debugfs_show(struct seq_file *m, void *v)
{
const struct blk_mq_debugfs_attr *attr = m->private;
void *data = d_inode(m->file->f_path.dentry->d_parent)->i_private;
return attr->show(data, m);
}
static ssize_t blk_mq_debugfs_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct seq_file *m = file->private_data;
const struct blk_mq_debugfs_attr *attr = m->private;
void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
/*
* Attributes that only implement .seq_ops are read-only and 'attr' is
* the same with 'data' in this case.
*/
if (attr == data || !attr->write)
return -EPERM;
return attr->write(data, buf, count, ppos);
}
static int blk_mq_debugfs_open(struct inode *inode, struct file *file)
{
const struct blk_mq_debugfs_attr *attr = inode->i_private;
void *data = d_inode(file->f_path.dentry->d_parent)->i_private;
struct seq_file *m;
int ret;
if (attr->seq_ops) {
ret = seq_open(file, attr->seq_ops);
if (!ret) {
m = file->private_data;
m->private = data;
}
return ret;
}
if (WARN_ON_ONCE(!attr->show))
return -EPERM;
return single_open(file, blk_mq_debugfs_show, inode->i_private);
}
static int blk_mq_debugfs_release(struct inode *inode, struct file *file)
{
const struct blk_mq_debugfs_attr *attr = inode->i_private;
if (attr->show)
return single_release(inode, file);
else
return seq_release(inode, file);
}
static const struct file_operations blk_mq_debugfs_fops = {
.open = blk_mq_debugfs_open,
.read = seq_read,
.write = blk_mq_debugfs_write,
.llseek = seq_lseek,
.release = blk_mq_debugfs_release,
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_hctx_attrs[] = {
{"state", 0400, hctx_state_show},
{"flags", 0400, hctx_flags_show},
{"dispatch", 0400, .seq_ops = &hctx_dispatch_seq_ops},
{"busy", 0400, hctx_busy_show},
{"ctx_map", 0400, hctx_ctx_map_show},
{"tags", 0400, hctx_tags_show},
{"tags_bitmap", 0400, hctx_tags_bitmap_show},
{"sched_tags", 0400, hctx_sched_tags_show},
{"sched_tags_bitmap", 0400, hctx_sched_tags_bitmap_show},
{"io_poll", 0600, hctx_io_poll_show, hctx_io_poll_write},
{"dispatched", 0600, hctx_dispatched_show, hctx_dispatched_write},
{"queued", 0600, hctx_queued_show, hctx_queued_write},
{"run", 0600, hctx_run_show, hctx_run_write},
{"active", 0400, hctx_active_show},
{"dispatch_busy", 0400, hctx_dispatch_busy_show},
{},
};
static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
{"rq_list", 0400, .seq_ops = &ctx_rq_list_seq_ops},
{"dispatched", 0600, ctx_dispatched_show, ctx_dispatched_write},
{"merged", 0600, ctx_merged_show, ctx_merged_write},
{"completed", 0600, ctx_completed_show, ctx_completed_write},
{},
};
static bool debugfs_create_files(struct dentry *parent, void *data,
const struct blk_mq_debugfs_attr *attr)
{
d_inode(parent)->i_private = data;
for (; attr->name; attr++) {
if (!debugfs_create_file(attr->name, attr->mode, parent,
(void *)attr, &blk_mq_debugfs_fops))
return false;
}
return true;
}
int blk_mq_debugfs_register(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
if (!blk_debugfs_root)
return -ENOENT;
q->debugfs_dir = debugfs_create_dir(kobject_name(q->kobj.parent),
blk_debugfs_root);
if (!q->debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(q->debugfs_dir, q,
blk_mq_debugfs_queue_attrs))
goto err;
/*
* blk_mq_init_sched() attempted to do this already, but q->debugfs_dir
* didn't exist yet (because we don't know what to name the directory
* until the queue is registered to a gendisk).
*/
if (q->elevator && !q->sched_debugfs_dir)
blk_mq_debugfs_register_sched(q);
/* Similarly, blk_mq_init_hctx() couldn't do this previously. */
queue_for_each_hw_ctx(q, hctx, i) {
if (!hctx->debugfs_dir && blk_mq_debugfs_register_hctx(q, hctx))
goto err;
if (q->elevator && !hctx->sched_debugfs_dir &&
blk_mq_debugfs_register_sched_hctx(q, hctx))
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->sched_debugfs_dir = NULL;
q->debugfs_dir = NULL;
}
static int blk_mq_debugfs_register_ctx(struct blk_mq_hw_ctx *hctx,
struct blk_mq_ctx *ctx)
{
struct dentry *ctx_dir;
char name[20];
snprintf(name, sizeof(name), "cpu%u", ctx->cpu);
ctx_dir = debugfs_create_dir(name, hctx->debugfs_dir);
if (!ctx_dir)
return -ENOMEM;
if (!debugfs_create_files(ctx_dir, ctx, blk_mq_debugfs_ctx_attrs))
return -ENOMEM;
return 0;
}
int blk_mq_debugfs_register_hctx(struct request_queue *q,
struct blk_mq_hw_ctx *hctx)
{
struct blk_mq_ctx *ctx;
char name[20];
int i;
if (!q->debugfs_dir)
return -ENOENT;
snprintf(name, sizeof(name), "hctx%u", hctx->queue_num);
hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir);
if (!hctx->debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(hctx->debugfs_dir, hctx,
blk_mq_debugfs_hctx_attrs))
goto err;
hctx_for_each_ctx(hctx, ctx, i) {
if (blk_mq_debugfs_register_ctx(hctx, ctx))
goto err;
}
return 0;
err:
blk_mq_debugfs_unregister_hctx(hctx);
return -ENOMEM;
}
void blk_mq_debugfs_unregister_hctx(struct blk_mq_hw_ctx *hctx)
{
debugfs_remove_recursive(hctx->debugfs_dir);
hctx->sched_debugfs_dir = NULL;
hctx->debugfs_dir = NULL;
}
int blk_mq_debugfs_register_hctxs(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
queue_for_each_hw_ctx(q, hctx, i) {
if (blk_mq_debugfs_register_hctx(q, hctx))
return -ENOMEM;
}
return 0;
}
void blk_mq_debugfs_unregister_hctxs(struct request_queue *q)
{
struct blk_mq_hw_ctx *hctx;
int i;
queue_for_each_hw_ctx(q, hctx, i)
blk_mq_debugfs_unregister_hctx(hctx);
}
int blk_mq_debugfs_register_sched(struct request_queue *q)
{
struct elevator_type *e = q->elevator->type;
if (!q->debugfs_dir)
return -ENOENT;
if (!e->queue_debugfs_attrs)
return 0;
q->sched_debugfs_dir = debugfs_create_dir("sched", q->debugfs_dir);
if (!q->sched_debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(q->sched_debugfs_dir, q,
e->queue_debugfs_attrs))
goto err;
return 0;
err:
blk_mq_debugfs_unregister_sched(q);
return -ENOMEM;
}
void blk_mq_debugfs_unregister_sched(struct request_queue *q)
{
debugfs_remove_recursive(q->sched_debugfs_dir);
q->sched_debugfs_dir = NULL;
}
int blk_mq_debugfs_register_sched_hctx(struct request_queue *q,
struct blk_mq_hw_ctx *hctx)
{
struct elevator_type *e = q->elevator->type;
if (!hctx->debugfs_dir)
return -ENOENT;
if (!e->hctx_debugfs_attrs)
return 0;
hctx->sched_debugfs_dir = debugfs_create_dir("sched",
hctx->debugfs_dir);
if (!hctx->sched_debugfs_dir)
return -ENOMEM;
if (!debugfs_create_files(hctx->sched_debugfs_dir, hctx,
e->hctx_debugfs_attrs))
return -ENOMEM;
return 0;
}
void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx)
{
debugfs_remove_recursive(hctx->sched_debugfs_dir);
hctx->sched_debugfs_dir = NULL;
}