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-rw-r--r--block/blk-mq-debugfs.c994
1 files changed, 994 insertions, 0 deletions
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c
new file mode 100644
index 000000000..212e1e795
--- /dev/null
+++ b/block/blk-mq-debugfs.c
@@ -0,0 +1,994 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Facebook
+ */
+
+#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"
+#include "blk-rq-qos.h"
+
+static void print_stat(struct seq_file *m, struct blk_rq_stat *stat)
+{
+ if (stat->nr_samples) {
+ seq_printf(m, "samples=%d, mean=%llu, 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;
+}
+
+static int queue_pm_only_show(void *data, struct seq_file *m)
+{
+ struct request_queue *q = data;
+
+ seq_printf(m, "%d\n", atomic_read(&q->pm_only));
+ return 0;
+}
+
+#define QUEUE_FLAG_NAME(name) [QUEUE_FLAG_##name] = #name
+static const char *const blk_queue_flag_name[] = {
+ QUEUE_FLAG_NAME(STOPPED),
+ QUEUE_FLAG_NAME(DYING),
+ 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(STABLE_WRITES),
+ QUEUE_FLAG_NAME(POLL),
+ QUEUE_FLAG_NAME(WC),
+ QUEUE_FLAG_NAME(FUA),
+ 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(PCI_P2PDMA),
+ QUEUE_FLAG_NAME(ZONE_RESETALL),
+ QUEUE_FLAG_NAME(RQ_ALLOC_TIME),
+ QUEUE_FLAG_NAME(HCTX_ACTIVE),
+ QUEUE_FLAG_NAME(NOWAIT),
+};
+#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 },
+ { "pm_only", 0600, queue_pm_only_show, NULL },
+ { "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),
+ HCTX_STATE_NAME(INACTIVE),
+};
+#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_QUEUE_SHARED),
+ HCTX_FLAG_NAME(BLOCKING),
+ HCTX_FLAG_NAME(NO_SCHED),
+ HCTX_FLAG_NAME(STACKING),
+ HCTX_FLAG_NAME(TAG_HCTX_SHARED),
+};
+#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 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(NOWAIT),
+ CMD_FLAG_NAME(NOUNMAP),
+ CMD_FLAG_NAME(HIPRI),
+};
+#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(SOFTBARRIER),
+ RQF_NAME(FLUSH_SEQ),
+ RQF_NAME(MIXED_MERGE),
+ RQF_NAME(MQ_INFLIGHT),
+ RQF_NAME(DONTPREP),
+ 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 = req_op(rq);
+ const char *op_str = blk_op_str(op);
+
+ seq_printf(m, "%p {.op=", rq);
+ if (strcmp(op_str, "UNKNOWN") == 0)
+ seq_printf(m, "%u", op);
+ else
+ seq_printf(m, "%s", op_str);
+ 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. Returns true to
+ * keep iterating requests.
+ */
+static bool hctx_show_busy_rq(struct request *rq, void *data, bool reserved)
+{
+ const struct show_busy_params *params = data;
+
+ if (rq->mq_hctx == params->hctx)
+ __blk_mq_debugfs_rq_show(params->m, rq);
+
+ return true;
+}
+
+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 const char *const hctx_types[] = {
+ [HCTX_TYPE_DEFAULT] = "default",
+ [HCTX_TYPE_READ] = "read",
+ [HCTX_TYPE_POLL] = "poll",
+};
+
+static int hctx_type_show(void *data, struct seq_file *m)
+{
+ struct blk_mq_hw_ctx *hctx = data;
+
+ BUILD_BUG_ON(ARRAY_SIZE(hctx_types) != HCTX_MAX_TYPES);
+ seq_printf(m, "%s\n", hctx_types[hctx->type]);
+ 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;
+}
+
+#define CTX_RQ_SEQ_OPS(name, type) \
+static void *ctx_##name##_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_lists[type], *pos); \
+} \
+ \
+static void *ctx_##name##_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_lists[type], pos); \
+} \
+ \
+static void ctx_##name##_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_##name##_rq_list_seq_ops = { \
+ .start = ctx_##name##_rq_list_start, \
+ .next = ctx_##name##_rq_list_next, \
+ .stop = ctx_##name##_rq_list_stop, \
+ .show = blk_mq_debugfs_rq_show, \
+}
+
+CTX_RQ_SEQ_OPS(default, HCTX_TYPE_DEFAULT);
+CTX_RQ_SEQ_OPS(read, HCTX_TYPE_READ);
+CTX_RQ_SEQ_OPS(poll, HCTX_TYPE_POLL);
+
+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);
+
+ 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},
+ {"type", 0400, hctx_type_show},
+ {},
+};
+
+static const struct blk_mq_debugfs_attr blk_mq_debugfs_ctx_attrs[] = {
+ {"default_rq_list", 0400, .seq_ops = &ctx_default_rq_list_seq_ops},
+ {"read_rq_list", 0400, .seq_ops = &ctx_read_rq_list_seq_ops},
+ {"poll_rq_list", 0400, .seq_ops = &ctx_poll_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 void debugfs_create_files(struct dentry *parent, void *data,
+ const struct blk_mq_debugfs_attr *attr)
+{
+ if (IS_ERR_OR_NULL(parent))
+ return;
+
+ d_inode(parent)->i_private = data;
+
+ for (; attr->name; attr++)
+ debugfs_create_file(attr->name, attr->mode, parent,
+ (void *)attr, &blk_mq_debugfs_fops);
+}
+
+void blk_mq_debugfs_register(struct request_queue *q)
+{
+ struct blk_mq_hw_ctx *hctx;
+ int i;
+
+ debugfs_create_files(q->debugfs_dir, q, blk_mq_debugfs_queue_attrs);
+
+ /*
+ * 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);
+ if (q->elevator && !hctx->sched_debugfs_dir)
+ blk_mq_debugfs_register_sched_hctx(q, hctx);
+ }
+
+ if (q->rq_qos) {
+ struct rq_qos *rqos = q->rq_qos;
+
+ while (rqos) {
+ blk_mq_debugfs_register_rqos(rqos);
+ rqos = rqos->next;
+ }
+ }
+}
+
+void blk_mq_debugfs_unregister(struct request_queue *q)
+{
+ q->sched_debugfs_dir = NULL;
+}
+
+static void 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);
+
+ debugfs_create_files(ctx_dir, ctx, blk_mq_debugfs_ctx_attrs);
+}
+
+void 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;
+
+ snprintf(name, sizeof(name), "hctx%u", hctx->queue_num);
+ hctx->debugfs_dir = debugfs_create_dir(name, q->debugfs_dir);
+
+ debugfs_create_files(hctx->debugfs_dir, hctx, blk_mq_debugfs_hctx_attrs);
+
+ hctx_for_each_ctx(hctx, ctx, i)
+ blk_mq_debugfs_register_ctx(hctx, ctx);
+}
+
+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;
+}
+
+void 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)
+ blk_mq_debugfs_register_hctx(q, hctx);
+}
+
+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);
+}
+
+void blk_mq_debugfs_register_sched(struct request_queue *q)
+{
+ struct elevator_type *e = q->elevator->type;
+
+ /*
+ * If the parent directory has not been created yet, return, we will be
+ * called again later on and the directory/files will be created then.
+ */
+ if (!q->debugfs_dir)
+ return;
+
+ if (!e->queue_debugfs_attrs)
+ return;
+
+ q->sched_debugfs_dir = debugfs_create_dir("sched", q->debugfs_dir);
+
+ debugfs_create_files(q->sched_debugfs_dir, q, e->queue_debugfs_attrs);
+}
+
+void blk_mq_debugfs_unregister_sched(struct request_queue *q)
+{
+ debugfs_remove_recursive(q->sched_debugfs_dir);
+ q->sched_debugfs_dir = NULL;
+}
+
+void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos)
+{
+ debugfs_remove_recursive(rqos->debugfs_dir);
+ rqos->debugfs_dir = NULL;
+}
+
+void blk_mq_debugfs_register_rqos(struct rq_qos *rqos)
+{
+ struct request_queue *q = rqos->q;
+ const char *dir_name = rq_qos_id_to_name(rqos->id);
+
+ if (rqos->debugfs_dir || !rqos->ops->debugfs_attrs)
+ return;
+
+ if (!q->rqos_debugfs_dir)
+ q->rqos_debugfs_dir = debugfs_create_dir("rqos",
+ q->debugfs_dir);
+
+ rqos->debugfs_dir = debugfs_create_dir(dir_name,
+ rqos->q->rqos_debugfs_dir);
+
+ debugfs_create_files(rqos->debugfs_dir, rqos, rqos->ops->debugfs_attrs);
+}
+
+void blk_mq_debugfs_unregister_queue_rqos(struct request_queue *q)
+{
+ debugfs_remove_recursive(q->rqos_debugfs_dir);
+ q->rqos_debugfs_dir = NULL;
+}
+
+void blk_mq_debugfs_register_sched_hctx(struct request_queue *q,
+ struct blk_mq_hw_ctx *hctx)
+{
+ struct elevator_type *e = q->elevator->type;
+
+ if (!e->hctx_debugfs_attrs)
+ return;
+
+ hctx->sched_debugfs_dir = debugfs_create_dir("sched",
+ hctx->debugfs_dir);
+ debugfs_create_files(hctx->sched_debugfs_dir, hctx,
+ e->hctx_debugfs_attrs);
+}
+
+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;
+}