diff options
| author | Jens Axboe <jens.axboe@oracle.com> | 2008-05-07 09:51:23 +0200 |
|---|---|---|
| committer | Jens Axboe <jens.axboe@oracle.com> | 2008-05-07 09:51:23 +0200 |
| commit | 6d63c275572d1e6f00d4fa154f16fbb0d8c2d2bf (patch) | |
| tree | 715f4bab902f117c958a929e44cd0b2257e3be29 | |
| parent | dbaf2c003e151ad9231778819b0977f95e20e06f (diff) | |
cfq-iosched: make io priorities inherit CPU scheduling class as well as nice
We currently set all processes to the best-effort scheduling class,
regardless of what CPU scheduling class they belong to. Improve that
so that we correctly track idle and rt scheduling classes as well.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
| -rw-r--r-- | block/cfq-iosched.c | 4 | ||||
| -rw-r--r-- | include/linux/ioprio.h | 14 |
2 files changed, 16 insertions, 2 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 7f909d2f488..b399c62936e 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1303,10 +1303,10 @@ static void cfq_init_prio_data(struct cfq_queue *cfqq, struct io_context *ioc) printk(KERN_ERR "cfq: bad prio %x\n", ioprio_class); case IOPRIO_CLASS_NONE: /* - * no prio set, place us in the middle of the BE classes + * no prio set, inherit CPU scheduling settings */ cfqq->ioprio = task_nice_ioprio(tsk); - cfqq->ioprio_class = IOPRIO_CLASS_BE; + cfqq->ioprio_class = task_nice_ioclass(tsk); break; case IOPRIO_CLASS_RT: cfqq->ioprio = task_ioprio(ioc); diff --git a/include/linux/ioprio.h b/include/linux/ioprio.h index 2a3bb1bb743..f98a656b17e 100644 --- a/include/linux/ioprio.h +++ b/include/linux/ioprio.h @@ -68,6 +68,20 @@ static inline int task_nice_ioprio(struct task_struct *task) } /* + * This is for the case where the task hasn't asked for a specific IO class. + * Check for idle and rt task process, and return appropriate IO class. + */ +static inline int task_nice_ioclass(struct task_struct *task) +{ + if (task->policy == SCHED_IDLE) + return IOPRIO_CLASS_IDLE; + else if (task->policy == SCHED_FIFO || task->policy == SCHED_RR) + return IOPRIO_CLASS_RT; + else + return IOPRIO_CLASS_BE; +} + +/* * For inheritance, return the highest of the two given priorities */ extern int ioprio_best(unsigned short aprio, unsigned short bprio); |