From: Jens Axboe Date: Tue, 12 Apr 2011 08:12:19 +0000 (+0200) Subject: block: fixup block IO unplug trace call X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=94b5eb28b41cc79d9713696e0005ae167b5afd1b;p=deliverable%2Flinux.git block: fixup block IO unplug trace call It was removed with the on-stack plugging, readd it and track the depth of requests added when flushing the plug. Signed-off-by: Jens Axboe --- diff --git a/block/blk-core.c b/block/blk-core.c index eeaca0998df5..d20ce1e849c8 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2668,12 +2668,19 @@ static int plug_rq_cmp(void *priv, struct list_head *a, struct list_head *b) return !(rqa->q <= rqb->q); } +static void queue_unplugged(struct request_queue *q, unsigned int depth) +{ + trace_block_unplug_io(q, depth); + __blk_run_queue(q, false); +} + static void flush_plug_list(struct blk_plug *plug) { struct request_queue *q; unsigned long flags; struct request *rq; LIST_HEAD(list); + unsigned int depth; BUG_ON(plug->magic != PLUG_MAGIC); @@ -2688,6 +2695,7 @@ static void flush_plug_list(struct blk_plug *plug) } q = NULL; + depth = 0; local_irq_save(flags); while (!list_empty(&list)) { rq = list_entry_rq(list.next); @@ -2696,10 +2704,11 @@ static void flush_plug_list(struct blk_plug *plug) BUG_ON(!rq->q); if (rq->q != q) { if (q) { - __blk_run_queue(q, false); + queue_unplugged(q, depth); spin_unlock(q->queue_lock); } q = rq->q; + depth = 0; spin_lock(q->queue_lock); } rq->cmd_flags &= ~REQ_ON_PLUG; @@ -2711,10 +2720,12 @@ static void flush_plug_list(struct blk_plug *plug) __elv_add_request(q, rq, ELEVATOR_INSERT_FLUSH); else __elv_add_request(q, rq, ELEVATOR_INSERT_SORT_MERGE); + + depth++; } if (q) { - __blk_run_queue(q, false); + queue_unplugged(q, depth); spin_unlock(q->queue_lock); } diff --git a/include/trace/events/block.h b/include/trace/events/block.h index 43a985390bb6..006e60b58306 100644 --- a/include/trace/events/block.h +++ b/include/trace/events/block.h @@ -401,9 +401,9 @@ TRACE_EVENT(block_plug, DECLARE_EVENT_CLASS(block_unplug, - TP_PROTO(struct request_queue *q), + TP_PROTO(struct request_queue *q, unsigned int depth), - TP_ARGS(q), + TP_ARGS(q, depth), TP_STRUCT__entry( __field( int, nr_rq ) @@ -411,7 +411,7 @@ DECLARE_EVENT_CLASS(block_unplug, ), TP_fast_assign( - __entry->nr_rq = q->rq.count[READ] + q->rq.count[WRITE]; + __entry->nr_rq = depth; memcpy(__entry->comm, current->comm, TASK_COMM_LEN); ), @@ -421,15 +421,16 @@ DECLARE_EVENT_CLASS(block_unplug, /** * block_unplug_io - release of operations requests in request queue * @q: request queue to unplug + * @depth: number of requests just added to the queue * * Unplug request queue @q because device driver is scheduled to work * on elements in the request queue. */ DEFINE_EVENT(block_unplug, block_unplug_io, - TP_PROTO(struct request_queue *q), + TP_PROTO(struct request_queue *q, unsigned int depth), - TP_ARGS(q) + TP_ARGS(q, depth) ); /** diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 824708cbfb7b..3e3970d53d14 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -850,13 +850,13 @@ static void blk_add_trace_plug(void *ignore, struct request_queue *q) __blk_add_trace(bt, 0, 0, 0, BLK_TA_PLUG, 0, 0, NULL); } -static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q) +static void blk_add_trace_unplug_io(void *ignore, struct request_queue *q, + unsigned int depth) { struct blk_trace *bt = q->blk_trace; if (bt) { - unsigned int pdu = q->rq.count[READ] + q->rq.count[WRITE]; - __be64 rpdu = cpu_to_be64(pdu); + __be64 rpdu = cpu_to_be64(depth); __blk_add_trace(bt, 0, 0, 0, BLK_TA_UNPLUG_IO, 0, sizeof(rpdu), &rpdu);