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| author | Namhyung Kim <namhyung@gmail.com> | 2011-05-24 10:23:21 +0200 |
|---|---|---|
| committer | Jens Axboe <jaxboe@fusionio.com> | 2011-05-24 10:23:21 +0200 |
| commit | 229836bd63c5413a4f8eed93d610b432be141e9b (patch) | |
| tree | a55fa492dbcde4c8f179d58d07165bdff872c34e /block/cfq-iosched.c | |
| parent | b9f8ce059940064a732da49b5d6e618381dad956 (diff) | |
| download | lwn-229836bd63c5413a4f8eed93d610b432be141e9b.tar.gz lwn-229836bd63c5413a4f8eed93d610b432be141e9b.zip | |
cfq-iosched: reduce bit operations in cfq_choose_req()
Reduce the number of bit operations in cfq_choose_req() on average
(and worst) cases.
Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 00763e510228..7ffceddee420 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -667,15 +667,11 @@ cfq_choose_req(struct cfq_data *cfqd, struct request *rq1, struct request *rq2, if (rq2 == NULL) return rq1; - if (rq_is_sync(rq1) && !rq_is_sync(rq2)) - return rq1; - else if (rq_is_sync(rq2) && !rq_is_sync(rq1)) - return rq2; - if ((rq1->cmd_flags & REQ_META) && !(rq2->cmd_flags & REQ_META)) - return rq1; - else if ((rq2->cmd_flags & REQ_META) && - !(rq1->cmd_flags & REQ_META)) - return rq2; + if (rq_is_sync(rq1) != rq_is_sync(rq2)) + return rq_is_sync(rq1) ? rq1 : rq2; + + if ((rq1->cmd_flags ^ rq2->cmd_flags) & REQ_META) + return rq1->cmd_flags & REQ_META ? rq1 : rq2; s1 = blk_rq_pos(rq1); s2 = blk_rq_pos(rq2); |