aleph/lkl_linux
1
0
Fork 0
mirror of https://github.com/lkl/linux.git synced 2025-12-19 08:03:01 +09:00
Code Issues Packages Projects Releases Wiki Activity

block: consolidate struct request timestamp fields

Browse Source 
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>
This commit is contained in:
Omar Sandoval
2018-05-09 02:08:53 -07:00
committed by Jens Axboe
parent 4bc6339a58
commit 522a777566
10 changed files with 30 additions and 76 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
block/blk-stat.c
View File

@@ -47,15 +47,14 @@ static void __blk_stat_add(struct blk_rq_stat *stat, u64 value)
stat->nr_samples++;
}
void blk_stat_add(struct request *rq)
void blk_stat_add(struct request *rq, u64 now)
{
struct request_queue *q = rq->q;
struct blk_stat_callback *cb;
struct blk_rq_stat *stat;
int bucket;
u64 now, value;
u64 value;
now = ktime_get_ns();
value = (now >= rq->io_start_time_ns) ? now - rq->io_start_time_ns : 0;
blk_throtl_stat_add(rq, value);