[PATCH 2/5] block: simplify and extended the block_bio_merge tracepoint class

Christoph Hellwig
2020-11-30T18:06:11Z

The block_bio_merge tracepoint class can be reused for most bio-based
tracepoints. For that is just needs to lose the superflous and rq
parameters.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
block/blk-core.c | 2 +-
block/blk-merge.c | 4 +-
block/blk-mq.c | 2 +-
block/bounce.c | 2 +-
include/trace/events/block.h | 158 ++++++++---------------------------
kernel/trace/blktrace.c | 41 +++------
6 files changed, 48 insertions(+), 161 deletions(-)

diff --git a/block/blk-core.c b/block/blk-core.c
index cee568389b7e11..cb24654983e1e4 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -907,7 +907,7 @@ static noinline_for_stack bool submit_bio_checks(struct bio *bio)
blkcg_bio_issue_init(bio);

if (!bio_flagged(bio, BIO_TRACE_COMPLETION)) {
- trace_block_bio_queue(q, bio);
+ trace_block_bio_queue(bio);
/* Now that enqueuing has been traced, we need to trace
* completion as well.
*/
diff --git a/block/blk-merge.c b/block/blk-merge.c
index cb351ab9b77dbd..1a46d5bbd399e3 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -922,7 +922,7 @@ static enum bio_merge_status bio_attempt_back_merge(struct request *req,
if (!ll_back_merge_fn(req, bio, nr_segs))
return BIO_MERGE_FAILED;

- trace_block_bio_backmerge(req->q, req, bio);
+ trace_block_bio_backmerge(bio);
rq_qos_merge(req->q, req, bio);

if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
@@ -946,7 +946,7 @@ static enum bio_merge_status bio_attempt_front_merge(struct request *req,
if (!ll_front_merge_fn(req, bio, nr_segs))
return BIO_MERGE_FAILED;

- trace_block_bio_frontmerge(req->q, req, bio);
+ trace_block_bio_frontmerge(bio);
rq_qos_merge(req->q, req, bio);

if ((req->cmd_flags & REQ_FAILFAST_MASK) != ff)
diff --git a/block/blk-mq.c b/block/blk-mq.c
index a2593748fa5342..13636458f32f1c 100644
--- a/block/blk-mq.c
+++ b/block/blk-mq.c
@@ -2183,7 +2183,7 @@ blk_qc_t blk_mq_submit_bio(struct bio *bio)
goto queue_exit;
}

- trace_block_getrq(q, bio, bio->bi_opf);
+ trace_block_getrq(bio);

rq_qos_track(q, rq, bio);

diff --git a/block/bounce.c b/block/bounce.c
index 162a6eee89996a..d3f51acd6e3b51 100644
--- a/block/bounce.c
+++ b/block/bounce.c
@@ -340,7 +340,7 @@ static void __blk_queue_bounce(struct request_queue *q, struct bio **bio_orig,
}
}

- trace_block_bio_bounce(q, *bio_orig);
+ trace_block_bio_bounce(*bio_orig);

bio->bi_flags |= (1 << BIO_BOUNCED);

diff --git a/include/trace/events/block.h b/include/trace/events/block.h
index 76459cf750e14d..506c29dc7c76fd 100644
--- a/include/trace/events/block.h
+++ b/include/trace/events/block.h
@@ -226,45 +226,6 @@ DEFINE_EVENT(block_rq, block_rq_merge,
TP_ARGS(q, rq)
);

-/**
- * block_bio_bounce - used bounce buffer when processing block operation
- * @q: queue holding the block operation
- * @bio: block operation
- *
- * A bounce buffer was used to handle the block operation @bio in @q.
- * This occurs when hardware limitations prevent a direct transfer of
- * data between the @bio data memory area and the IO device. Use of a
- * bounce buffer requires extra copying of data and decreases
- * performance.
- */
-TRACE_EVENT(block_bio_bounce,
-
- TP_PROTO(struct request_queue *q, struct bio *bio),
-
- TP_ARGS(q, bio),
-
- TP_STRUCT__entry(
- __field( dev_t, dev )
- __field( sector_t, sector )
- __field( unsigned int, nr_sector )
- __array( char, rwbs, RWBS_LEN )
- __array( char, comm, TASK_COMM_LEN )
- ),
-
- TP_fast_assign(
- __entry->dev = bio_dev(bio);
- __entry->sector = bio->bi_iter.bi_sector;
- __entry->nr_sector = bio_sectors(bio);
- blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
- memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
- ),
-
- TP_printk("%d,%d %s %llu + %u [%s]",
- MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
- (unsigned long long)__entry->sector,
- __entry->nr_sector, __entry->comm)
-);
-
/**
* block_bio_complete - completed all work on the block operation
* @q: queue holding the block operation
@@ -301,11 +262,11 @@ TRACE_EVENT(block_bio_complete,
__entry->nr_sector, __entry->error)
);

-DECLARE_EVENT_CLASS(block_bio_merge,
+DECLARE_EVENT_CLASS(block_bio,

- TP_PROTO(struct request_queue *q, struct request *rq, struct bio *bio),
+ TP_PROTO(struct bio *bio),

- TP_ARGS(q, rq, bio),
+ TP_ARGS(bio),

TP_STRUCT__entry(
__field( dev_t, dev )
@@ -329,116 +290,63 @@ DECLARE_EVENT_CLASS(block_bio_merge,
__entry->nr_sector, __entry->comm)
);

+/**
+ * block_bio_bounce - used bounce buffer when processing block operation
+ * @bio: block operation
+ *
+ * A bounce buffer was used to handle the block operation @bio in @q.
+ * This occurs when hardware limitations prevent a direct transfer of
+ * data between the @bio data memory area and the IO device. Use of a
+ * bounce buffer requires extra copying of data and decreases
+ * performance.
+ */
+DEFINE_EVENT(block_bio, block_bio_bounce,
+ TP_PROTO(struct bio *bio),
+ TP_ARGS(bio)
+);
+
/**
* block_bio_backmerge - merging block operation to the end of an existing operation
- * @q: queue holding operation
- * @rq: request bio is being merged into
* @bio: new block operation to merge
*
- * Merging block request @bio to the end of an existing block request
- * in queue @q.
+ * Merging block request @bio to the end of an existing block request.
*/
-DEFINE_EVENT(block_bio_merge, block_bio_backmerge,
-
- TP_PROTO(struct request_queue *q, struct request *rq, struct bio *bio),
-
- TP_ARGS(q, rq, bio)
+DEFINE_EVENT(block_bio, block_bio_backmerge,
+ TP_PROTO(struct bio *bio),
+ TP_ARGS(bio)
);

/**
* block_bio_frontmerge - merging block operation to the beginning of an existing operation
- * @q: queue holding operation
- * @rq: request bio is being merged into
* @bio: new block operation to merge
*
- * Merging block IO operation @bio to the beginning of an existing block
- * operation in queue @q.
+ * Merging block IO operation @bio to the beginning of an existing block request.
*/
-DEFINE_EVENT(block_bio_merge, block_bio_frontmerge,
-
- TP_PROTO(struct request_queue *q, struct request *rq, struct bio *bio),
-
- TP_ARGS(q, rq, bio)
+DEFINE_EVENT(block_bio, block_bio_frontmerge,
+ TP_PROTO(struct bio *bio),
+ TP_ARGS(bio)
);

/**
* block_bio_queue - putting new block IO operation in queue
- * @q: queue holding operation
* @bio: new block operation
*
* About to place the block IO operation @bio into queue @q.
*/
-TRACE_EVENT(block_bio_queue,
-
- TP_PROTO(struct request_queue *q, struct bio *bio),
-
- TP_ARGS(q, bio),
-
- TP_STRUCT__entry(
- __field( dev_t, dev )
- __field( sector_t, sector )
- __field( unsigned int, nr_sector )
- __array( char, rwbs, RWBS_LEN )
- __array( char, comm, TASK_COMM_LEN )
- ),
-
- TP_fast_assign(
- __entry->dev = bio_dev(bio);
- __entry->sector = bio->bi_iter.bi_sector;
- __entry->nr_sector = bio_sectors(bio);
- blk_fill_rwbs(__entry->rwbs, bio->bi_opf, bio->bi_iter.bi_size);
- memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
- ),
-
- TP_printk("%d,%d %s %llu + %u [%s]",
- MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
- (unsigned long long)__entry->sector,
- __entry->nr_sector, __entry->comm)
-);
-
-DECLARE_EVENT_CLASS(block_get_rq,
-
- TP_PROTO(struct request_queue *q, struct bio *bio, int rw),
-
- TP_ARGS(q, bio, rw),
-
- TP_STRUCT__entry(
- __field( dev_t, dev )
- __field( sector_t, sector )
- __field( unsigned int, nr_sector )
- __array( char, rwbs, RWBS_LEN )
- __array( char, comm, TASK_COMM_LEN )
- ),
-
- TP_fast_assign(
- __entry->dev = bio ? bio_dev(bio) : 0;
- __entry->sector = bio ? bio->bi_iter.bi_sector : 0;
- __entry->nr_sector = bio ? bio_sectors(bio) : 0;
- blk_fill_rwbs(__entry->rwbs,
- bio ? bio->bi_opf : 0, __entry->nr_sector);
- memcpy(__entry->comm, current->comm, TASK_COMM_LEN);
- ),
-
- TP_printk("%d,%d %s %llu + %u [%s]",
- MAJOR(__entry->dev), MINOR(__entry->dev), __entry->rwbs,
- (unsigned long long)__entry->sector,
- __entry->nr_sector, __entry->comm)
+DEFINE_EVENT(block_bio, block_bio_queue,
+ TP_PROTO(struct bio *bio),
+ TP_ARGS(bio)
);

/**
* block_getrq - get a free request entry in queue for block IO operations
- * @q: queue for operations
* @bio: pending block IO operation (can be %NULL)
- * @rw: low bit indicates a read (%0) or a write (%1)
*
- * A request struct for queue @q has been allocated to handle the
- * block IO operation @bio.
+ * A request struct has been allocated to handle the block IO operation @bio.
*/
-DEFINE_EVENT(block_get_rq, block_getrq,
-
- TP_PROTO(struct request_queue *q, struct bio *bio, int rw),
-
- TP_ARGS(q, bio, rw)
+DEFINE_EVENT(block_bio, block_getrq,
+ TP_PROTO(struct bio *bio),
+ TP_ARGS(bio)
);

/**
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index ced589df304b57..7ab88e00c15765 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -906,10 +906,9 @@ static void blk_add_trace_bio(struct request_queue *q, struct bio *bio,
rcu_read_unlock();
}

-static void blk_add_trace_bio_bounce(void *ignore,
- struct request_queue *q, struct bio *bio)
+static void blk_add_trace_bio_bounce(void *ignore, struct bio *bio)
{
- blk_add_trace_bio(q, bio, BLK_TA_BOUNCE, 0);
+ blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_BOUNCE, 0);
}

static void blk_add_trace_bio_complete(void *ignore,
@@ -919,44 +918,24 @@ static void blk_add_trace_bio_complete(void *ignore,
blk_status_to_errno(bio->bi_status));
}

-static void blk_add_trace_bio_backmerge(void *ignore,
- struct request_queue *q,
- struct request *rq,
- struct bio *bio)
+static void blk_add_trace_bio_backmerge(void *ignore, struct bio *bio)
{
- blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE, 0);
+ blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_BACKMERGE, 0);
}

-static void blk_add_trace_bio_frontmerge(void *ignore,
- struct request_queue *q,
- struct request *rq,
- struct bio *bio)
+static void blk_add_trace_bio_frontmerge(void *ignore, struct bio *bio)
{
- blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE, 0);
+ blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_FRONTMERGE, 0);
}

-static void blk_add_trace_bio_queue(void *ignore,
- struct request_queue *q, struct bio *bio)
+static void blk_add_trace_bio_queue(void *ignore, struct bio *bio)
{
- blk_add_trace_bio(q, bio, BLK_TA_QUEUE, 0);
+ blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_QUEUE, 0);
}

-static void blk_add_trace_getrq(void *ignore,
- struct request_queue *q,
- struct bio *bio, int rw)
+static void blk_add_trace_getrq(void *ignore, struct bio *bio)
{
- if (bio)
- blk_add_trace_bio(q, bio, BLK_TA_GETRQ, 0);
- else {
- struct blk_trace *bt;
-
- rcu_read_lock();
- bt = rcu_dereference(q->blk_trace);
- if (bt)
- __blk_add_trace(bt, 0, 0, rw, 0, BLK_TA_GETRQ, 0, 0,
- NULL, 0);
- rcu_read_unlock();
- }
+ blk_add_trace_bio(bio->bi_disk->queue, bio, BLK_TA_GETRQ, 0);
}

static void blk_add_trace_plug(void *ignore, struct request_queue *q)
--
2.29.2