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| author | Jens Axboe <jens.axboe@oracle.com> | 2010-02-23 08:40:43 +0100 |
|---|---|---|
| committer | Jens Axboe <jens.axboe@oracle.com> | 2010-02-23 08:40:43 +0100 |
| commit | 79da0644a8e0838522828f106e4049639eea6baf (patch) | |
| tree | 4dbb8e1a3a4be78a79f14e8ebac5d6fe817a2fb4 | |
| parent | 9f3a6284880ceea452903e2043c88d7226736318 (diff) | |
| download | linux-79da0644a8e0838522828f106e4049639eea6baf.tar.gz linux-79da0644a8e0838522828f106e4049639eea6baf.tar.bz2 linux-79da0644a8e0838522828f106e4049639eea6baf.zip | |
Revert "block: improve queue_should_plug() by looking at IO depths"
This reverts commit fb1e75389bd06fd5987e9cda1b4e0305c782f854.
"Benjamin S." <sbenni@gmx.de> reports that the patch in question
causes a big drop in sequential throughput for him, dropping from
200MB/sec down to only 70MB/sec.
Needs to be investigated more fully, for now lets just revert the
offending commit.
Conflicts:
include/linux/blkdev.h
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| -rw-r--r-- | block/blk-core.c | 11 | ||||
| -rw-r--r-- | include/linux/blkdev.h | 4 |
2 files changed, 3 insertions, 12 deletions
diff --git a/block/blk-core.c b/block/blk-core.c index 718897e6d37f..d1a9a0a64f95 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1147,7 +1147,7 @@ void init_request_from_bio(struct request *req, struct bio *bio) */ static inline bool queue_should_plug(struct request_queue *q) { - return !(blk_queue_nonrot(q) && blk_queue_queuing(q)); + return !(blk_queue_nonrot(q) && blk_queue_tagged(q)); } static int __make_request(struct request_queue *q, struct bio *bio) @@ -1859,15 +1859,8 @@ void blk_dequeue_request(struct request *rq) * and to it is freed is accounted as io that is in progress at * the driver side. */ - if (blk_account_rq(rq)) { + if (blk_account_rq(rq)) q->in_flight[rq_is_sync(rq)]++; - /* - * Mark this device as supporting hardware queuing, if - * we have more IOs in flight than 4. - */ - if (!blk_queue_queuing(q) && queue_in_flight(q) > 4) - set_bit(QUEUE_FLAG_CQ, &q->queue_flags); - } } /** diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 5c8018977efa..1896e868854f 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -461,8 +461,7 @@ struct request_queue #define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */ #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */ #define QUEUE_FLAG_IO_STAT 15 /* do IO stats */ -#define QUEUE_FLAG_CQ 16 /* hardware does queuing */ -#define QUEUE_FLAG_DISCARD 17 /* supports DISCARD */ +#define QUEUE_FLAG_DISCARD 16 /* supports DISCARD */ #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ (1 << QUEUE_FLAG_CLUSTER) | \ @@ -586,7 +585,6 @@ enum { #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) -#define blk_queue_queuing(q) test_bit(QUEUE_FLAG_CQ, &(q)->queue_flags) #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags) #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags) |