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>

1 files changed, 2 insertions, 2 deletions

diff --git a/block/bfq-iosched.c b/block/bfq-iosched.c
index 771ae9730ac6..ebc264c87a09 100644
--- a/block/bfq-iosched.c
+++ b/block/bfq-iosched.c
@@ -4778,8 +4778,8 @@ static void bfq_finish_requeue_request(struct request *rq)
 
         if (rq->rq_flags & RQF_STARTED)
                 bfqg_stats_update_completion(bfqq_group(bfqq),
-                                             rq_start_time_ns(rq),
-                                             rq_io_start_time_ns(rq),
+                                             rq->start_time_ns,
+                                             rq->io_start_time_ns,
                                              rq->cmd_flags);
 
         if (likely(rq->rq_flags & RQF_STARTED)) {