diff options
author | Ming Lei <ming.lei@redhat.com> | 2018-12-17 09:46:00 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2018-12-16 19:53:47 -0700 |
commit | cc56694f132a8f5fa9334e3afe990de8c3378866 (patch) | |
tree | c67715ced5609fdcd34e95c3dcc24e6bc8ae494a /block | |
parent | f9824952ee1cd02ae1a74e35e0e8653f8a4db772 (diff) | |
download | linux-next-cc56694f132a8f5fa9334e3afe990de8c3378866.tar.gz |
blk-mq-debugfs: support rq_qos
blk-mq-debugfs has been proved as very helpful for debug some
tough issues, such as IO hang.
We have seen blk-wbt related IO hang several times, even inside
Red Hat BZ, there is such report not sovled yet, so this patch
adds support debugfs on rq_qos.
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
-rw-r--r-- | block/blk-mq-debugfs.c | 54 | ||||
-rw-r--r-- | block/blk-mq-debugfs.h | 17 | ||||
-rw-r--r-- | block/blk-rq-qos.c | 2 | ||||
-rw-r--r-- | block/blk-rq-qos.h | 24 |
4 files changed, 97 insertions, 0 deletions
diff --git a/block/blk-mq-debugfs.c b/block/blk-mq-debugfs.c index a32bb79d6c95..2793e91bc7a4 100644 --- a/block/blk-mq-debugfs.c +++ b/block/blk-mq-debugfs.c @@ -23,6 +23,7 @@ #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) { @@ -856,6 +857,15 @@ int blk_mq_debugfs_register(struct request_queue *q) goto err; } + if (q->rq_qos) { + struct rq_qos *rqos = q->rq_qos; + + while (rqos) { + blk_mq_debugfs_register_rqos(rqos); + rqos = rqos->next; + } + } + return 0; err: @@ -978,6 +988,50 @@ void blk_mq_debugfs_unregister_sched(struct request_queue *q) 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; +} + +int 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 (!q->debugfs_dir) + return -ENOENT; + + if (rqos->debugfs_dir || !rqos->ops->debugfs_attrs) + return 0; + + if (!q->rqos_debugfs_dir) { + q->rqos_debugfs_dir = debugfs_create_dir("rqos", + q->debugfs_dir); + if (!q->rqos_debugfs_dir) + return -ENOMEM; + } + + rqos->debugfs_dir = debugfs_create_dir(dir_name, + rqos->q->rqos_debugfs_dir); + if (!rqos->debugfs_dir) + return -ENOMEM; + + if (!debugfs_create_files(rqos->debugfs_dir, rqos, + rqos->ops->debugfs_attrs)) + goto err; + return 0; + err: + blk_mq_debugfs_unregister_rqos(rqos); + return -ENOMEM; +} + +void blk_mq_debugfs_unregister_queue_rqos(struct request_queue *q) +{ + debugfs_remove_recursive(q->rqos_debugfs_dir); + q->rqos_debugfs_dir = NULL; +} + int blk_mq_debugfs_register_sched_hctx(struct request_queue *q, struct blk_mq_hw_ctx *hctx) { diff --git a/block/blk-mq-debugfs.h b/block/blk-mq-debugfs.h index a9160be12be0..8c9012a578c1 100644 --- a/block/blk-mq-debugfs.h +++ b/block/blk-mq-debugfs.h @@ -31,6 +31,10 @@ void blk_mq_debugfs_unregister_sched(struct request_queue *q); int blk_mq_debugfs_register_sched_hctx(struct request_queue *q, struct blk_mq_hw_ctx *hctx); void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx); + +int blk_mq_debugfs_register_rqos(struct rq_qos *rqos); +void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos); +void blk_mq_debugfs_unregister_queue_rqos(struct request_queue *q); #else static inline int blk_mq_debugfs_register(struct request_queue *q) { @@ -78,6 +82,19 @@ static inline int blk_mq_debugfs_register_sched_hctx(struct request_queue *q, static inline void blk_mq_debugfs_unregister_sched_hctx(struct blk_mq_hw_ctx *hctx) { } + +static inline int blk_mq_debugfs_register_rqos(struct rq_qos *rqos) +{ + return 0; +} + +static inline void blk_mq_debugfs_unregister_rqos(struct rq_qos *rqos) +{ +} + +static inline void blk_mq_debugfs_unregister_queue_rqos(struct request_queue *q) +{ +} #endif #ifdef CONFIG_BLK_DEBUG_FS_ZONED diff --git a/block/blk-rq-qos.c b/block/blk-rq-qos.c index e932ef9d2718..d169d7188fa6 100644 --- a/block/blk-rq-qos.c +++ b/block/blk-rq-qos.c @@ -264,6 +264,8 @@ void rq_qos_wait(struct rq_wait *rqw, void *private_data, void rq_qos_exit(struct request_queue *q) { + blk_mq_debugfs_unregister_queue_rqos(q); + while (q->rq_qos) { struct rq_qos *rqos = q->rq_qos; q->rq_qos = rqos->next; diff --git a/block/blk-rq-qos.h b/block/blk-rq-qos.h index 8678875de420..3c85f26d3846 100644 --- a/block/blk-rq-qos.h +++ b/block/blk-rq-qos.h @@ -7,6 +7,10 @@ #include <linux/atomic.h> #include <linux/wait.h> +#include "blk-mq-debugfs.h" + +struct blk_mq_debugfs_attr; + enum rq_qos_id { RQ_QOS_WBT, RQ_QOS_CGROUP, @@ -22,6 +26,9 @@ struct rq_qos { struct request_queue *q; enum rq_qos_id id; struct rq_qos *next; +#ifdef CONFIG_BLK_DEBUG_FS + struct dentry *debugfs_dir; +#endif }; struct rq_qos_ops { @@ -33,6 +40,7 @@ struct rq_qos_ops { void (*done_bio)(struct rq_qos *, struct bio *); void (*cleanup)(struct rq_qos *, struct bio *); void (*exit)(struct rq_qos *); + const struct blk_mq_debugfs_attr *debugfs_attrs; }; struct rq_depth { @@ -66,6 +74,17 @@ static inline struct rq_qos *blkcg_rq_qos(struct request_queue *q) return rq_qos_id(q, RQ_QOS_CGROUP); } +static inline const char *rq_qos_id_to_name(enum rq_qos_id id) +{ + switch (id) { + case RQ_QOS_WBT: + return "wbt"; + case RQ_QOS_CGROUP: + return "cgroup"; + } + return "unknown"; +} + static inline void rq_wait_init(struct rq_wait *rq_wait) { atomic_set(&rq_wait->inflight, 0); @@ -76,6 +95,9 @@ static inline void rq_qos_add(struct request_queue *q, struct rq_qos *rqos) { rqos->next = q->rq_qos; q->rq_qos = rqos; + + if (rqos->ops->debugfs_attrs) + blk_mq_debugfs_register_rqos(rqos); } static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos) @@ -91,6 +113,8 @@ static inline void rq_qos_del(struct request_queue *q, struct rq_qos *rqos) } prev = cur; } + + blk_mq_debugfs_unregister_rqos(rqos); } typedef bool (acquire_inflight_cb_t)(struct rq_wait *rqw, void *private_data); |