From 522a777566f5669606a1227bf13f3fb40963780b Mon Sep 17 00:00:00 2001 From: Omar Sandoval Date: Wed, 9 May 2018 02:08:53 -0700 Subject: 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 Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) (limited to 'block/cfq-iosched.c') diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 652ca064de206..6b9f6b1cd33b9 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; } -- cgit v1.2.3