From 805f6b5e1cbfedfb9b3d354013e7f4b13a79270f Mon Sep 17 00:00:00 2001 From: Tao Ma Date: Fri, 11 Mar 2011 20:11:59 +0100 Subject: [PATCH] blktrace: Use rq->cmd_flags directly in blk_add_trace_rq. In blk_add_trace_rq, we only chose the minor 2 bits from request's cmd_flags and did some check for discard. so most of other flags(e.g, REQ_SYNC) are missing. For example, with a sync write after blkparse we get: 8,16 1 1 0.001776503 7509 A WS 1349632 + 1024 <- (8,17) 1347584 8,16 1 2 0.001776813 7509 Q WS 1349632 + 1024 [dd] 8,16 1 3 0.001780395 7509 G WS 1349632 + 1024 [dd] 8,16 1 5 0.001783186 7509 I W 1349632 + 1024 [dd] 8,16 1 11 0.001816987 7509 D W 1349632 + 1024 [dd] 8,16 0 2 0.006218192 0 C W 1349632 + 1024 [0] Since now we have integrated the flags of both bio and request, it is safe to pass rq->cmd_flags directly to __blk_add_trace. With this patch, after a sync write we get: 8,16 1 1 0.001776900 5425 A WS 1189888 + 1024 <- (8,17) 1187840 8,16 1 2 0.001777179 5425 Q WS 1189888 + 1024 [dd] 8,16 1 3 0.001780797 5425 G WS 1189888 + 1024 [dd] 8,16 1 5 0.001783402 5425 I WS 1189888 + 1024 [dd] 8,16 1 11 0.001817468 5425 D WS 1189888 + 1024 [dd] 8,16 0 2 0.005640709 0 C WS 1189888 + 1024 [0] Signed-off-by: Tao Ma Acked-by: Jeff Moyer Signed-off-by: Jens Axboe --- kernel/trace/blktrace.c | 15 ++++----------- 1 file changed, 4 insertions(+), 11 deletions(-) diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index cbafed7d4f38..7aa40f8e182d 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -703,28 +703,21 @@ void blk_trace_shutdown(struct request_queue *q) * **/ static void blk_add_trace_rq(struct request_queue *q, struct request *rq, - u32 what) + u32 what) { struct blk_trace *bt = q->blk_trace; - int rw = rq->cmd_flags & 0x03; if (likely(!bt)) return; - if (rq->cmd_flags & REQ_DISCARD) - rw |= REQ_DISCARD; - - if (rq->cmd_flags & REQ_SECURE) - rw |= REQ_SECURE; - if (rq->cmd_type == REQ_TYPE_BLOCK_PC) { what |= BLK_TC_ACT(BLK_TC_PC); - __blk_add_trace(bt, 0, blk_rq_bytes(rq), rw, + __blk_add_trace(bt, 0, blk_rq_bytes(rq), 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), rw, - what, rq->errors, 0, NULL); + __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq), + rq->cmd_flags, what, rq->errors, 0, NULL); } }