diff options
| author | Omar Sandoval <osandov@fb.com> | 2018-05-09 02:08:53 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2018-05-09 08:33:09 -0600 |
| commit | 522a777566f5669606a1227bf13f3fb40963780b (patch) | |
| tree | 7d37c9d591e5a9abb4fd1209f1c503ae1a0e8475 /block/blk-merge.c | |
| parent | 4bc6339a583cec650b05d6fdcc83f03f941c1a3b (diff) | |
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/blk-merge.c')
| -rw-r--r-- | block/blk-merge.c | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/block/blk-merge.c b/block/blk-merge.c index 782940c65d8a..5573d0fbec53 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -724,13 +724,12 @@ static struct request *attempt_merge(struct request_queue *q, } /* - * At this point we have either done a back merge - * or front merge. We need the smaller start_time of - * the merged requests to be the current request - * for accounting purposes. + * At this point we have either done a back merge or front merge. We + * need the smaller start_time_ns of the merged requests to be the + * current request for accounting purposes. */ - if (time_after(req->start_time, next->start_time)) - req->start_time = next->start_time; + if (next->start_time_ns < req->start_time_ns) + req->start_time_ns = next->start_time_ns; req->biotail->bi_next = next->bio; req->biotail = next->biotail; |