block: Optimize ioprio_best()

Since ioprio_best() translates IOPRIO_CLASS_NONE into IOPRIO_CLASS_BE
and since lower numerical priority values represent a higher priority
a simple numerical comparison is sufficient.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Adam Manzanares <adam.manzanares@wdc.com>
Tested-by: Adam Manzanares <adam.manzanares@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Bart Van Assche 2017-04-19 14:01:28 -07:00 committed by Jens Axboe
parent 0be0dee64e
commit 9a87182c4b
1 changed files with 1 additions and 11 deletions

View File

@ -163,22 +163,12 @@ out:
int ioprio_best(unsigned short aprio, unsigned short bprio)
{
unsigned short aclass;
unsigned short bclass;
if (!ioprio_valid(aprio))
aprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM);
if (!ioprio_valid(bprio))
bprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, IOPRIO_NORM);
aclass = IOPRIO_PRIO_CLASS(aprio);
bclass = IOPRIO_PRIO_CLASS(bprio);
if (aclass == bclass)
return min(aprio, bprio);
if (aclass > bclass)
return bprio;
else
return aprio;
return min(aprio, bprio);
}
SYSCALL_DEFINE2(ioprio_get, int, which, int, who)