[PATCH v3 0/3] blk-mq: fix start_time_ns and alloc_time_ns for pre-allocated rq

chengming.zhou
2023-06-28T12:47:05Z

From: Chengming Zhou <zhouchengming@bytedance.com>

Hello,

This patchset fix start_time_ns and alloc_time_ns for pre-allocated rq.

patch 1 and 2 is preparation that we ktime_get_ns() outside batched rq init
for batched requests start_time_ns setting.

patch 3 is the fix patch that we set alloc_time_ns and start_time_ns
to now when the pre-allocated rq is actually used.

v3:
- Skip setting the alloc_time_ns and start_time_ns during pre-allocation,
which is clearer, as suggested by Tejun.
- [v2] https://lore.kernel.org/all/20230626050405.781253-1-chengming.zhou@linux.dev/

v2:
- Let blk_mq_rq_ctx_init() receive start_time_ns for batched time setting.
- Set alloc_time_ns and start_time_ns when the pre-allocated rq is actually
used, as suggested by Tejun.
- [v1] https://lore.kernel.org/all/20230601053919.3639954-1-chengming.zhou@linux.dev/

Chengming Zhou (3):
blk-mq: always use __blk_mq_alloc_requests() to alloc and init rq
blk-mq: ktime_get_ns() only once for batched requests init
blk-mq: fix start_time_ns and alloc_time_ns for pre-allocated rq

block/blk-mq.c | 94 ++++++++++++++++++++++++------------------
include/linux/blk-mq.h | 6 +--
2 files changed, 56 insertions(+), 44 deletions(-)

--
2.39.2