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| author | Jens Axboe <axboe@fb.com> | 2015-06-10 08:01:20 -0600 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-06-10 08:01:20 -0600 |
| commit | 0bb979472a7401022109e81dd89d777adea58710 (patch) | |
| tree | 27cf4730d269d037ad5b0db1f89d5ecf788cb3d0 /block/cfq-iosched.c | |
| parent | ae11f7efda05dc568521924c890c80d0be908d43 (diff) | |
| download | lwn-0bb979472a7401022109e81dd89d777adea58710.tar.gz lwn-0bb979472a7401022109e81dd89d777adea58710.zip | |
cfq-iosched: fix the setting of IOPS mode on SSDs
A previous commit wanted to make CFQ default to IOPS mode on
non-rotational storage, however it did so when the queue was
initialized and the non-rotational flag is only set later on
in the probe.
Add an elevator hook that gets called off the add_disk() path,
at that point we know that feature probing has finished, and
we can reliably check for the various flags that drivers can
set.
Fixes: 41c0126b ("block: Make CFQ default to IOPS mode on SSDs")
Tested-by: Romain Francoise <romain@orebokech.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block/cfq-iosched.c')
| -rw-r--r-- | block/cfq-iosched.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index c808ad87652d..d1d0cb235cd2 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -4508,7 +4508,7 @@ static int cfq_init_queue(struct request_queue *q, struct elevator_type *e) cfqd->cfq_slice[1] = cfq_slice_sync; cfqd->cfq_target_latency = cfq_target_latency; cfqd->cfq_slice_async_rq = cfq_slice_async_rq; - cfqd->cfq_slice_idle = blk_queue_nonrot(q) ? 0 : cfq_slice_idle; + cfqd->cfq_slice_idle = cfq_slice_idle; cfqd->cfq_group_idle = cfq_group_idle; cfqd->cfq_latency = 1; cfqd->hw_tag = -1; @@ -4525,6 +4525,18 @@ out_free: return ret; } +static void cfq_registered_queue(struct request_queue *q) +{ + struct elevator_queue *e = q->elevator; + struct cfq_data *cfqd = e->elevator_data; + + /* + * Default to IOPS mode with no idling for SSDs + */ + if (blk_queue_nonrot(q)) + cfqd->cfq_slice_idle = 0; +} + /* * sysfs parts below --> */ @@ -4640,6 +4652,7 @@ static struct elevator_type iosched_cfq = { .elevator_may_queue_fn = cfq_may_queue, .elevator_init_fn = cfq_init_queue, .elevator_exit_fn = cfq_exit_queue, + .elevator_registered_fn = cfq_registered_queue, }, .icq_size = sizeof(struct cfq_io_cq), .icq_align = __alignof__(struct cfq_io_cq), |