dm crypt: use WQ_HIGHPRI for the IO and crypt workqueues (a1b89132) · Commits · 戴 / test

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>

drivers/md/dm-crypt.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -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";

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