GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-07-22 06:41:39 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

block: get rid of struct blk_issue_stat

Browse source 
struct blk_issue_stat squashes three things into one u64:

- The time the driver started working on a request
- The original size of the request (for the io.low controller)
- Flags for writeback throttling

It turns out that on x86_64, we have a 4 byte hole in struct request
which we can fill with the non-timestamp fields from blk_issue_stat,
simplifying things quite a bit.

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 02:08:50 -07:00 • committed by Jens Axboe
parent 5238dcf413
commit 544ccc8dc9
10 changed files with 41 additions and 77 deletions
Download patch file Download diff file Expand all files Collapse all files

26
include/linux/blkdev.h
View file

@ -206,8 +206,18 @@ struct request {
struct gendisk *rq_disk;
struct hd_struct *part;
unsigned long start_time;
struct blk_issue_stat issue_stat;
/* Number of scatter-gather DMA addr+len pairs after
/* Time that I/O was submitted to the device. */
u64 io_start_time_ns;
#ifdef CONFIG_BLK_WBT
unsigned short wbt_flags;
#endif
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
unsigned short throtl_size;
#endif
/*
* Number of scatter-gather DMA addr+len pairs after
* physical address coalescing is performed.
*/
unsigned short nr_phys_segments;
@ -267,8 +277,8 @@ struct request {
#ifdef CONFIG_BLK_CGROUP
struct request_list *rl; /* rl this rq is alloced from */
unsigned long long start_time_ns;
unsigned long long io_start_time_ns; /* when passed to hardware */
unsigned long long cgroup_start_time_ns;
unsigned long long cgroup_io_start_time_ns; /* when passed to hardware */
#endif
};
@ -1797,25 +1807,25 @@ int kblockd_mod_delayed_work_on(int cpu, struct delayed_work *dwork, unsigned lo
static inline void set_start_time_ns(struct request *req)
{
preempt_disable();
req->start_time_ns = sched_clock();
req->cgroup_start_time_ns = sched_clock();
preempt_enable();
}
static inline void set_io_start_time_ns(struct request *req)
{
preempt_disable();
req->io_start_time_ns = sched_clock();
req->cgroup_io_start_time_ns = sched_clock();
preempt_enable();
}
static inline uint64_t rq_start_time_ns(struct request *req)
{
return req->start_time_ns;
return req->cgroup_start_time_ns;
}
static inline uint64_t rq_io_start_time_ns(struct request *req)
{
return req->io_start_time_ns;
return req->cgroup_io_start_time_ns;
}
#else
static inline void set_start_time_ns(struct request *req) {}