[PATCH] dm: add WQ_PERCPU to alloc_workqueue users

[PATCH] dm: add WQ_PERCPU to alloc_workqueue users

[Marco Crivellari]

This continues the effort to refactor workqueue APIs, which began with
the introduction of new workqueues and a new alloc_workqueue flag in:

   commit 128ea9f6ccfb ("workqueue: Add system_percpu_wq and system_dfl_wq")
   commit 930c2ea566af ("workqueue: Add new WQ_PERCPU flag")

The refactoring is going to alter the default behavior of
alloc_workqueue() to be unbound by default.

With the introduction of the WQ_PERCPU flag (equivalent to !WQ_UNBOUND),
any alloc_workqueue() caller that doesn’t explicitly specify WQ_UNBOUND
must now use WQ_PERCPU. For more details see the Link tag below.

In order to keep alloc_workqueue() behavior identical, explicitly request
WQ_PERCPU.

Link: https://lore.kernel.org/all/20250221112003.1dSuoGyc@linutronix.de/
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Marco Crivellari <marco.crivellari@suse.com>
---
 drivers/md/dm-bufio.c              |  3 ++-
 drivers/md/dm-cache-target.c       |  3 ++-
 drivers/md/dm-clone-target.c       |  3 ++-
 drivers/md/dm-crypt.c              |  6 ++++--
 drivers/md/dm-delay.c              |  4 +++-
 drivers/md/dm-integrity.c          | 15 ++++++++++-----
 drivers/md/dm-kcopyd.c             |  3 ++-
 drivers/md/dm-log-userspace-base.c |  3 ++-
 drivers/md/dm-mpath.c              |  5 +++--
 drivers/md/dm-raid1.c              |  5 +++--
 drivers/md/dm-snap-persistent.c    |  3 ++-
 drivers/md/dm-stripe.c             |  2 +-
 drivers/md/dm-verity-target.c      |  4 +++-
 drivers/md/dm-writecache.c         |  3 ++-
 drivers/md/dm.c                    |  3 ++-
 drivers/md/md.c                    |  4 ++--
 16 files changed, 45 insertions(+), 24 deletions(-)

diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c
index 5235f3e4924b..f41f649c01d4 100644
--- a/drivers/md/dm-bufio.c
+++ b/drivers/md/dm-bufio.c
@@ -2833,7 +2833,8 @@ static int __init dm_bufio_init(void)
 	__cache_size_refresh();
 	mutex_unlock(&dm_bufio_clients_lock);
 
-	dm_bufio_wq = alloc_workqueue("dm_bufio_cache", WQ_MEM_RECLAIM, 0);
+	dm_bufio_wq = alloc_workqueue("dm_bufio_cache",
+				      WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 	if (!dm_bufio_wq)
 		return -ENOMEM;
 
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index a10d75a562db..7bad7cc87d37 100644
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -2533,7 +2533,8 @@ static int cache_create(struct cache_args *ca, struct cache **result)
 		goto bad;
 	}
 
-	cache->wq = alloc_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM, 0);
+	cache->wq = alloc_workqueue("dm-" DM_MSG_PREFIX,
+				    WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 	if (!cache->wq) {
 		*error = "could not create workqueue for metadata object";
 		goto bad;
diff --git a/drivers/md/dm-clone-target.c b/drivers/md/dm-clone-target.c
index e956d980672c..b25845e36274 100644
--- a/drivers/md/dm-clone-target.c
+++ b/drivers/md/dm-clone-target.c
@@ -1877,7 +1877,8 @@ static int clone_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	clone->hydration_offset = 0;
 	atomic_set(&clone->hydrations_in_flight, 0);
 
-	clone->wq = alloc_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM, 0);
+	clone->wq = alloc_workqueue("dm-" DM_MSG_PREFIX,
+				    WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 	if (!clone->wq) {
 		ti->error = "Failed to allocate workqueue";
 		r = -ENOMEM;
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 79704fbc523b..0e479de75ad0 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -3400,7 +3400,9 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags))
 		common_wq_flags |= WQ_HIGHPRI;
 
-	cc->io_queue = alloc_workqueue("kcryptd_io-%s-%d", common_wq_flags, 1, devname, wq_id);
+	cc->io_queue = alloc_workqueue("kcryptd_io-%s-%d",
+				       common_wq_flags | WQ_PERCPU, 1,
+				       devname, wq_id);
 	if (!cc->io_queue) {
 		ti->error = "Couldn't create kcryptd io queue";
 		goto bad;
@@ -3408,7 +3410,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 
 	if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) {
 		cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d",
-						  common_wq_flags | WQ_CPU_INTENSIVE,
+						  common_wq_flags | WQ_CPU_INTENSIVE | WQ_PERCPU,
 						  1, devname, wq_id);
 	} else {
 		/*
diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c
index 4bb6553278c7..029f04776490 100644
--- a/drivers/md/dm-delay.c
+++ b/drivers/md/dm-delay.c
@@ -290,7 +290,9 @@ static int delay_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	} else {
 		timer_setup(&dc->delay_timer, handle_delayed_timer, 0);
 		INIT_WORK(&dc->flush_expired_bios, flush_expired_bios);
-		dc->kdelayd_wq = alloc_workqueue("kdelayd", WQ_MEM_RECLAIM, 0);
+		dc->kdelayd_wq = alloc_workqueue("kdelayd",
+						 WQ_MEM_RECLAIM | WQ_PERCPU,
+						 0);
 		if (!dc->kdelayd_wq) {
 			ret = -EINVAL;
 			DMERR("Couldn't start kdelayd");
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c
index 170bf67a2edd..564d8099361a 100644
--- a/drivers/md/dm-integrity.c
+++ b/drivers/md/dm-integrity.c
@@ -4990,7 +4990,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned int argc, char **argv
 	}
 
 	ic->metadata_wq = alloc_workqueue("dm-integrity-metadata",
-					  WQ_MEM_RECLAIM, METADATA_WORKQUEUE_MAX_ACTIVE);
+					  WQ_MEM_RECLAIM | WQ_PERCPU,
+					  METADATA_WORKQUEUE_MAX_ACTIVE);
 	if (!ic->metadata_wq) {
 		ti->error = "Cannot allocate workqueue";
 		r = -ENOMEM;
@@ -5008,7 +5009,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned int argc, char **argv
 		goto bad;
 	}
 
-	ic->offload_wq = alloc_workqueue("dm-integrity-offload", WQ_MEM_RECLAIM,
+	ic->offload_wq = alloc_workqueue("dm-integrity-offload",
+					  WQ_MEM_RECLAIM | WQ_PERCPU,
 					  METADATA_WORKQUEUE_MAX_ACTIVE);
 	if (!ic->offload_wq) {
 		ti->error = "Cannot allocate workqueue";
@@ -5016,7 +5018,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned int argc, char **argv
 		goto bad;
 	}
 
-	ic->commit_wq = alloc_workqueue("dm-integrity-commit", WQ_MEM_RECLAIM, 1);
+	ic->commit_wq = alloc_workqueue("dm-integrity-commit",
+					WQ_MEM_RECLAIM | WQ_PERCPU, 1);
 	if (!ic->commit_wq) {
 		ti->error = "Cannot allocate workqueue";
 		r = -ENOMEM;
@@ -5025,7 +5028,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned int argc, char **argv
 	INIT_WORK(&ic->commit_work, integrity_commit);
 
 	if (ic->mode == 'J' || ic->mode == 'B') {
-		ic->writer_wq = alloc_workqueue("dm-integrity-writer", WQ_MEM_RECLAIM, 1);
+		ic->writer_wq = alloc_workqueue("dm-integrity-writer",
+						WQ_MEM_RECLAIM | WQ_PERCPU, 1);
 		if (!ic->writer_wq) {
 			ti->error = "Cannot allocate workqueue";
 			r = -ENOMEM;
@@ -5197,7 +5201,8 @@ static int dm_integrity_ctr(struct dm_target *ti, unsigned int argc, char **argv
 	}
 
 	if (ic->internal_hash) {
-		ic->recalc_wq = alloc_workqueue("dm-integrity-recalc", WQ_MEM_RECLAIM, 1);
+		ic->recalc_wq = alloc_workqueue("dm-integrity-recalc",
+						WQ_MEM_RECLAIM | WQ_PERCPU, 1);
 		if (!ic->recalc_wq) {
 			ti->error = "Cannot allocate workqueue";
 			r = -ENOMEM;
diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c
index 6ea75436a433..cec9a60227b6 100644
--- a/drivers/md/dm-kcopyd.c
+++ b/drivers/md/dm-kcopyd.c
@@ -934,7 +934,8 @@ struct dm_kcopyd_client *dm_kcopyd_client_create(struct dm_kcopyd_throttle *thro
 		goto bad_slab;
 
 	INIT_WORK(&kc->kcopyd_work, do_work);
-	kc->kcopyd_wq = alloc_workqueue("kcopyd", WQ_MEM_RECLAIM, 0);
+	kc->kcopyd_wq = alloc_workqueue("kcopyd", WQ_MEM_RECLAIM | WQ_PERCPU,
+					0);
 	if (!kc->kcopyd_wq) {
 		r = -ENOMEM;
 		goto bad_workqueue;
diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
index 9fbb4b48fb2b..607436804a8b 100644
--- a/drivers/md/dm-log-userspace-base.c
+++ b/drivers/md/dm-log-userspace-base.c
@@ -299,7 +299,8 @@ static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
 	}
 
 	if (lc->integrated_flush) {
-		lc->dmlog_wq = alloc_workqueue("dmlogd", WQ_MEM_RECLAIM, 0);
+		lc->dmlog_wq = alloc_workqueue("dmlogd",
+					       WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 		if (!lc->dmlog_wq) {
 			DMERR("couldn't start dmlogd");
 			r = -ENOMEM;
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index d5d6ef7ba838..c748e7f952c4 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -2328,7 +2328,8 @@ static int __init dm_multipath_init(void)
 {
 	int r = -ENOMEM;
 
-	kmultipathd = alloc_workqueue("kmpathd", WQ_MEM_RECLAIM, 0);
+	kmultipathd = alloc_workqueue("kmpathd", WQ_MEM_RECLAIM | WQ_PERCPU,
+				      0);
 	if (!kmultipathd) {
 		DMERR("failed to create workqueue kmpathd");
 		goto bad_alloc_kmultipathd;
@@ -2347,7 +2348,7 @@ static int __init dm_multipath_init(void)
 		goto bad_alloc_kmpath_handlerd;
 	}
 
-	dm_mpath_wq = alloc_workqueue("dm_mpath_wq", 0, 0);
+	dm_mpath_wq = alloc_workqueue("dm_mpath_wq", WQ_PERCPU, 0);
 	if (!dm_mpath_wq) {
 		DMERR("failed to create workqueue dm_mpath_wq");
 		goto bad_alloc_dm_mpath_wq;
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index 268f734ca9c3..943c0c6b2087 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -1128,7 +1128,8 @@ static int mirror_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	ti->num_discard_bios = 1;
 	ti->per_io_data_size = sizeof(struct dm_raid1_bio_record);
 
-	ms->kmirrord_wq = alloc_workqueue("kmirrord", WQ_MEM_RECLAIM, 0);
+	ms->kmirrord_wq = alloc_workqueue("kmirrord",
+					  WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 	if (!ms->kmirrord_wq) {
 		DMERR("couldn't start kmirrord");
 		r = -ENOMEM;
@@ -1500,7 +1501,7 @@ static int __init dm_mirror_init(void)
 {
 	int r;
 
-	dm_raid1_wq = alloc_workqueue("dm_raid1_wq", 0, 0);
+	dm_raid1_wq = alloc_workqueue("dm_raid1_wq", WQ_PERCPU, 0);
 	if (!dm_raid1_wq) {
 		DMERR("Failed to alloc workqueue");
 		return -ENOMEM;
diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index 568d10842b1f..0e13d60bfdd1 100644
--- a/drivers/md/dm-snap-persistent.c
+++ b/drivers/md/dm-snap-persistent.c
@@ -871,7 +871,8 @@ static int persistent_ctr(struct dm_exception_store *store, char *options)
 	atomic_set(&ps->pending_count, 0);
 	ps->callbacks = NULL;
 
-	ps->metadata_wq = alloc_workqueue("ksnaphd", WQ_MEM_RECLAIM, 0);
+	ps->metadata_wq = alloc_workqueue("ksnaphd",
+					  WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 	if (!ps->metadata_wq) {
 		DMERR("couldn't start header metadata update thread");
 		r = -ENOMEM;
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 1461dc740dae..1cff9df5b8b4 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -489,7 +489,7 @@ int __init dm_stripe_init(void)
 {
 	int r;
 
-	dm_stripe_wq = alloc_workqueue("dm_stripe_wq", 0, 0);
+	dm_stripe_wq = alloc_workqueue("dm_stripe_wq", WQ_PERCPU, 0);
 	if (!dm_stripe_wq)
 		return -ENOMEM;
 	r = dm_register_target(&stripe_target);
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 5c17472d7896..d00298d50ffb 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -1651,7 +1651,9 @@ static int verity_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	 * will fall-back to using it for error handling (or if the bufio cache
 	 * doesn't have required hashes).
 	 */
-	v->verify_wq = alloc_workqueue("kverityd", WQ_MEM_RECLAIM | WQ_HIGHPRI, 0);
+	v->verify_wq = alloc_workqueue("kverityd",
+				       WQ_MEM_RECLAIM | WQ_HIGHPRI | WQ_PERCPU,
+				       0);
 	if (!v->verify_wq) {
 		ti->error = "Cannot allocate workqueue";
 		r = -ENOMEM;
diff --git a/drivers/md/dm-writecache.c b/drivers/md/dm-writecache.c
index d8de4a3076a1..af54e289bceb 100644
--- a/drivers/md/dm-writecache.c
+++ b/drivers/md/dm-writecache.c
@@ -2275,7 +2275,8 @@ static int writecache_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 		goto bad;
 	}
 
-	wc->writeback_wq = alloc_workqueue("writecache-writeback", WQ_MEM_RECLAIM, 1);
+	wc->writeback_wq = alloc_workqueue("writecache-writeback",
+					   WQ_MEM_RECLAIM | WQ_PERCPU, 1);
 	if (!wc->writeback_wq) {
 		r = -ENOMEM;
 		ti->error = "Could not allocate writeback workqueue";
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index b63279202260..ea2c43cddde1 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2366,7 +2366,8 @@ static struct mapped_device *alloc_dev(int minor)
 
 	format_dev_t(md->name, MKDEV(_major, minor));
 
-	md->wq = alloc_workqueue("kdmflush/%s", WQ_MEM_RECLAIM, 0, md->name);
+	md->wq = alloc_workqueue("kdmflush/%s", WQ_MEM_RECLAIM | WQ_PERCPU, 0,
+				 md->name);
 	if (!md->wq)
 		goto bad;
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 6d73f6e196a9..3882a66bad85 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -10493,11 +10493,11 @@ static int __init md_init(void)
 		goto err_bitmap;
 
 	ret = -ENOMEM;
-	md_wq = alloc_workqueue("md", WQ_MEM_RECLAIM, 0);
+	md_wq = alloc_workqueue("md", WQ_MEM_RECLAIM | WQ_PERCPU, 0);
 	if (!md_wq)
 		goto err_wq;
 
-	md_misc_wq = alloc_workqueue("md_misc", 0, 0);
+	md_misc_wq = alloc_workqueue("md_misc", WQ_PERCPU, 0);
 	if (!md_misc_wq)
 		goto err_misc_wq;
 
-- 
2.52.0

Re: [PATCH] dm: add WQ_PERCPU to alloc_workqueue users

[Marco Crivellari]

On Tue, Jan 13, 2026 at 12:03 PM Marco Crivellari
<marco.crivellari@suse.com> wrote:
>  drivers/md/dm-bufio.c              |  3 ++-
>  drivers/md/dm-cache-target.c       |  3 ++-
>  drivers/md/dm-clone-target.c       |  3 ++-
>  drivers/md/dm-crypt.c              |  6 ++++--
>  drivers/md/dm-delay.c              |  4 +++-
>  drivers/md/dm-integrity.c          | 15 ++++++++++-----
>  drivers/md/dm-kcopyd.c             |  3 ++-
>  drivers/md/dm-log-userspace-base.c |  3 ++-
>  drivers/md/dm-mpath.c              |  5 +++--
>  drivers/md/dm-raid1.c              |  5 +++--
>  drivers/md/dm-snap-persistent.c    |  3 ++-
>  drivers/md/dm-stripe.c             |  2 +-
>  drivers/md/dm-verity-target.c      |  4 +++-
>  drivers/md/dm-writecache.c         |  3 ++-
>  drivers/md/dm.c                    |  3 ++-
>  drivers/md/md.c                    |  4 ++--
>  16 files changed, 45 insertions(+), 24 deletions(-)

Gentle ping.

Thanks!

-- 

Marco Crivellari

L3 Support Engineer

Re: [PATCH] dm: add WQ_PERCPU to alloc_workqueue users

[Mikulas Patocka]

[-- Attachment #1: Type: text/plain, Size: 1147 bytes --]



On Mon, 23 Feb 2026, Marco Crivellari wrote:

> On Tue, Jan 13, 2026 at 12:03 PM Marco Crivellari
> <marco.crivellari@suse.com> wrote:
> >  drivers/md/dm-bufio.c              |  3 ++-
> >  drivers/md/dm-cache-target.c       |  3 ++-
> >  drivers/md/dm-clone-target.c       |  3 ++-
> >  drivers/md/dm-crypt.c              |  6 ++++--
> >  drivers/md/dm-delay.c              |  4 +++-
> >  drivers/md/dm-integrity.c          | 15 ++++++++++-----
> >  drivers/md/dm-kcopyd.c             |  3 ++-
> >  drivers/md/dm-log-userspace-base.c |  3 ++-
> >  drivers/md/dm-mpath.c              |  5 +++--
> >  drivers/md/dm-raid1.c              |  5 +++--
> >  drivers/md/dm-snap-persistent.c    |  3 ++-
> >  drivers/md/dm-stripe.c             |  2 +-
> >  drivers/md/dm-verity-target.c      |  4 +++-
> >  drivers/md/dm-writecache.c         |  3 ++-
> >  drivers/md/dm.c                    |  3 ++-
> >  drivers/md/md.c                    |  4 ++--
> >  16 files changed, 45 insertions(+), 24 deletions(-)
> 
> Gentle ping.
> 
> Thanks!

Hi

The patch was already committed to 7.0-rc1. See the commit 
d4880868670198df321627a949e7b7f2d76cf54e.

Mikulas

Re: [PATCH] dm: add WQ_PERCPU to alloc_workqueue users

[Marco Crivellari]

On Mon, Feb 23, 2026 at 1:13 PM Mikulas Patocka <mpatocka@redhat.com> wrote:
> [...]
> Hi
>
> The patch was already committed to 7.0-rc1. See the commit
> d4880868670198df321627a949e7b7f2d76cf54e.
>
> Mikulas

Hi,

Ouch, many thanks!


-- 

Marco Crivellari

L3 Support Engineer