dm crypt: use WQ_HIGHPRI for the IO and crypt workqueues

Running dm-crypt with workqueues at the standard priority results in IO
competing for CPU time with standard user apps, which can lead to
pipeline bubbles and seriously degraded performance.  Move to using
WQ_HIGHPRI workqueues to protect against that.

Signed-off-by: Tim Murray <timmurray@google.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Tim Murray 2017-04-21 11:11:36 +02:00 committed by Mike Snitzer
parent c82feeec9a
commit a1b89132dc

View file

@ -2749,16 +2749,17 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
}
ret = -ENOMEM;
cc->io_queue = alloc_workqueue("kcryptd_io", WQ_MEM_RECLAIM, 1);
cc->io_queue = alloc_workqueue("kcryptd_io", WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
if (!cc->io_queue) {
ti->error = "Couldn't create kcryptd io queue";
goto bad;
}
if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
cc->crypt_queue = alloc_workqueue("kcryptd", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
cc->crypt_queue = alloc_workqueue("kcryptd", WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 1);
else
cc->crypt_queue = alloc_workqueue("kcryptd", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
cc->crypt_queue = alloc_workqueue("kcryptd",
WQ_HIGHPRI | WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
num_online_cpus());
if (!cc->crypt_queue) {
ti->error = "Couldn't create kcryptd queue";