From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752141AbaEWLaz (ORCPT ); Fri, 23 May 2014 07:30:55 -0400 Received: from ip4-83-240-18-248.cust.nbox.cz ([83.240.18.248]:43223 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751572AbaEWLan (ORCPT ); Fri, 23 May 2014 07:30:43 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: Roman Pen , Steven Rostedt , Frederic Weisbecker , Ingo Molnar , linux-kernel@vger.kernel.org, Jens Axboe , Jiri Slaby Subject: [patch added to the 3.12 stable tree] blktrace: fix accounting of partially completed requests Date: Fri, 23 May 2014 13:30:07 +0200 Message-Id: <1400844641-27494-9-git-send-email-jslaby@suse.cz> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1400844641-27494-1-git-send-email-jslaby@suse.cz> References: <1400844641-27494-1-git-send-email-jslaby@suse.cz> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Roman Pen This patch has been added to the 3.12 stable tree. If you have any objections, please let us know. =============== commit af5040da01ef980670b3741b3e10733ee3e33566 upstream. trace_block_rq_complete does not take into account that request can be partially completed, so we can get the following incorrect output of blkparser: C R 232 + 240 [0] C R 240 + 232 [0] C R 248 + 224 [0] C R 256 + 216 [0] but should be: C R 232 + 8 [0] C R 240 + 8 [0] C R 248 + 8 [0] C R 256 + 8 [0] Also, the whole output summary statistics of completed requests and final throughput will be incorrect. This patch takes into account real completion size of the request and fixes wrong completion accounting. Signed-off-by: Roman Pen CC: Steven Rostedt CC: Frederic Weisbecker CC: Ingo Molnar CC: linux-kernel@vger.kernel.org Signed-off-by: Jens Axboe Signed-off-by: Jiri Slaby --- block/blk-core.c | 2 +- include/trace/events/block.h | 33 ++++++++++++++++++++++++++++++--- kernel/trace/blktrace.c | 20 +++++++++++--------- 3 files changed, 42 insertions(+), 13 deletions(-) diff --git a/block/blk-core.c b/block/blk-core.c index fce4b9387f36..bf214ae98937 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -2297,7 +2297,7 @@ bool blk_update_request(struct request *req, int error, unsigned int nr_bytes) if (!req->bio) return false; - trace_block_rq_complete(req->q, req); + trace_block_rq_complete(req->q, req, nr_bytes); /* * For fs requests, rq is just carrier of independent bio's diff --git a/include/trace/events/block.h b/include/trace/events/block.h index 4c2301d2ef1a..2aaf370c462b 100644 --- a/include/trace/events/block.h +++ b/include/trace/events/block.h @@ -132,6 +132,7 @@ DEFINE_EVENT(block_rq_with_error, block_rq_requeue, * block_rq_complete - block IO operation completed by device driver * @q: queue containing the block operation request * @rq: block operations request + * @nr_bytes: number of completed bytes * * The block_rq_complete tracepoint event indicates that some portion * of operation request has been completed by the device driver. If @@ -139,11 +140,37 @@ DEFINE_EVENT(block_rq_with_error, block_rq_requeue, * do for the request. If @rq->bio is non-NULL then there is * additional work required to complete the request. */ -DEFINE_EVENT(block_rq_with_error, block_rq_complete, +TRACE_EVENT(block_rq_complete, - TP_PROTO(struct request_queue *q, struct request *rq), + TP_PROTO(struct request_queue *q, struct request *rq, + unsigned int nr_bytes), - TP_ARGS(q, rq) + TP_ARGS(q, rq, nr_bytes), + + TP_STRUCT__entry( + __field( dev_t, dev ) + __field( sector_t, sector ) + __field( unsigned int, nr_sector ) + __field( int, errors ) + __array( char, rwbs, RWBS_LEN ) + __dynamic_array( char, cmd, blk_cmd_buf_len(rq) ) + ), + + TP_fast_assign( + __entry->dev = rq->rq_disk ? disk_devt(rq->rq_disk) : 0; + __entry->sector = blk_rq_pos(rq); + __entry->nr_sector = nr_bytes >> 9; + __entry->errors = rq->errors; + + blk_fill_rwbs(__entry->rwbs, rq->cmd_flags, nr_bytes); + blk_dump_cmd(__get_str(cmd), rq); + ), + + TP_printk("%d,%d %s (%s) %llu + %u [%d]", + MAJOR(__entry->dev), MINOR(__entry->dev), + __entry->rwbs, __get_str(cmd), + (unsigned long long)__entry->sector, + __entry->nr_sector, __entry->errors) ); DECLARE_EVENT_CLASS(block_rq, diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 7f727b34280d..e0e5f73db5a4 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -703,6 +703,7 @@ void blk_trace_shutdown(struct request_queue *q) * blk_add_trace_rq - Add a trace for a request oriented action * @q: queue the io is for * @rq: the source request + * @nr_bytes: number of completed bytes * @what: the action * * Description: @@ -710,7 +711,7 @@ void blk_trace_shutdown(struct request_queue *q) * **/ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, - u32 what) + unsigned int nr_bytes, u32 what) { struct blk_trace *bt = q->blk_trace; @@ -719,11 +720,11 @@ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { what |= BLK_TC_ACT(BLK_TC_PC); - __blk_add_trace(bt, 0, blk_rq_bytes(rq), rq->cmd_flags, + __blk_add_trace(bt, 0, nr_bytes, rq->cmd_flags, what, rq->errors, rq->cmd_len, rq->cmd); } else { what |= BLK_TC_ACT(BLK_TC_FS); - __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), + __blk_add_trace(bt, blk_rq_pos(rq), nr_bytes, rq->cmd_flags, what, rq->errors, 0, NULL); } } @@ -731,33 +732,34 @@ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, static void blk_add_trace_rq_abort(void *ignore, struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_ABORT); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_ABORT); } static void blk_add_trace_rq_insert(void *ignore, struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_INSERT); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_INSERT); } static void blk_add_trace_rq_issue(void *ignore, struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_ISSUE); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_ISSUE); } static void blk_add_trace_rq_requeue(void *ignore, struct request_queue *q, struct request *rq) { - blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); + blk_add_trace_rq(q, rq, blk_rq_bytes(rq), BLK_TA_REQUEUE); } static void blk_add_trace_rq_complete(void *ignore, struct request_queue *q, - struct request *rq) + struct request *rq, + unsigned int nr_bytes) { - blk_add_trace_rq(q, rq, BLK_TA_COMPLETE); + blk_add_trace_rq(q, rq, nr_bytes, BLK_TA_COMPLETE); } /** -- 1.9.3