Khazhismel Kumykov <[email protected]> writes:
> mixing sched_clock() and ktime_get_ns() will give bad results, don't do
> it
>
> Fixes: 2613eab11996 ("dm mpath: add Historical Service Time Path Selector")
> Signed-off-by: Khazhismel Kumykov <[email protected]>
Looks good.
Reviewed-by: Gabriel Krisman Bertazi <[email protected]>
> ---
> drivers/md/dm-ps-historical-service-time.c | 11 +++++------
> 1 file changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/md/dm-ps-historical-service-time.c b/drivers/md/dm-ps-historical-service-time.c
> index 875bca30a0dd..82f2a06153dc 100644
> --- a/drivers/md/dm-ps-historical-service-time.c
> +++ b/drivers/md/dm-ps-historical-service-time.c
> @@ -27,7 +27,6 @@
> #include <linux/blkdev.h>
> #include <linux/slab.h>
> #include <linux/module.h>
> -#include <linux/sched/clock.h>
>
>
> #define DM_MSG_PREFIX "multipath historical-service-time"
> @@ -433,7 +432,7 @@ static struct dm_path *hst_select_path(struct path_selector *ps,
> {
> struct selector *s = ps->context;
> struct path_info *pi = NULL, *best = NULL;
> - u64 time_now = sched_clock();
> + u64 time_now = ktime_get_ns();
> struct dm_path *ret = NULL;
> unsigned long flags;
>
> @@ -474,7 +473,7 @@ static int hst_start_io(struct path_selector *ps, struct dm_path *path,
>
> static u64 path_service_time(struct path_info *pi, u64 start_time)
> {
> - u64 sched_now = ktime_get_ns();
> + u64 now = ktime_get_ns();
>
> /* if a previous disk request has finished after this IO was
> * sent to the hardware, pretend the submission happened
> @@ -483,11 +482,11 @@ static u64 path_service_time(struct path_info *pi, u64 start_time)
> if (time_after64(pi->last_finish, start_time))
> start_time = pi->last_finish;
>
> - pi->last_finish = sched_now;
> - if (time_before64(sched_now, start_time))
> + pi->last_finish = now;
> + if (time_before64(now, start_time))
> return 0;
>
> - return sched_now - start_time;
> + return now - start_time;
> }
>
> static int hst_end_io(struct path_selector *ps, struct dm_path *path,
--
Gabriel Krisman Bertazi