diff options
Diffstat (limited to 'block/blk-mq-debugfs.c')
| -rw-r--r-- | block/blk-mq-debugfs.c | 994 |
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, + ¶ms); + + 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; +} |