summaryrefslogtreecommitdiffstats
path: root/block/cfq-iosched.c
diff options
context:
space:
mode:
authorOmar Sandoval <osandov@fb.com>2018-05-09 02:08:53 -0700
committerJens Axboe <axboe@kernel.dk>2018-05-09 08:33:09 -0600
commit522a777566f5669606a1227bf13f3fb40963780b (patch)
tree7d37c9d591e5a9abb4fd1209f1c503ae1a0e8475 /block/cfq-iosched.c
parent4bc6339a583cec650b05d6fdcc83f03f941c1a3b (diff)
downloadlinux-0-day-522a777566f5669606a1227bf13f3fb40963780b.tar.gz
block: consolidate struct request timestamp fields
Currently, struct request has four timestamp fields: - A start time, set at get_request time, in jiffies, used for iostats - An I/O start time, set at start_request time, in ktime nanoseconds, used for blk-stats (i.e., wbt, kyber, hybrid polling) - Another start time and another I/O start time, used for cfq and bfq These can all be consolidated into one start time and one I/O start time, both in ktime nanoseconds, shaving off up to 16 bytes from struct request depending on the kernel config. Signed-off-by: Omar Sandoval <osandov@fb.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/cfq-iosched.c')
-rw-r--r--block/cfq-iosched.c15
1 files changed, 3 insertions, 12 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 652ca06..6b9f6b1 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -4228,8 +4228,8 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
cfqd->rq_in_driver--;
cfqq->dispatched--;
(RQ_CFQG(rq))->dispatched--;
- cfqg_stats_update_completion(cfqq->cfqg, rq_start_time_ns(rq),
- rq_io_start_time_ns(rq), rq->cmd_flags);
+ cfqg_stats_update_completion(cfqq->cfqg, rq->start_time_ns,
+ rq->io_start_time_ns, rq->cmd_flags);
cfqd->rq_in_flight[cfq_cfqq_sync(cfqq)]--;
@@ -4245,16 +4245,7 @@ static void cfq_completed_request(struct request_queue *q, struct request *rq)
cfqq_type(cfqq));
st->ttime.last_end_request = now;
- /*
- * We have to do this check in jiffies since start_time is in
- * jiffies and it is not trivial to convert to ns. If
- * cfq_fifo_expire[1] ever comes close to 1 jiffie, this test
- * will become problematic but so far we are fine (the default
- * is 128 ms).
- */
- if (!time_after(rq->start_time +
- nsecs_to_jiffies(cfqd->cfq_fifo_expire[1]),
- jiffies))
+ if (rq->start_time_ns + cfqd->cfq_fifo_expire[1] <= now)
cfqd->last_delayed_sync = now;
}