From: Breno Leitao Date: Mon, 11 May 2026 12:14:18 +0000 (-0700) Subject: workqueue: drop apply_wqattrs_lock()/unlock() wrappers X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=dfca46365afc030fb09bb40226514c500202dcdc;p=thirdparty%2Fkernel%2Flinux.git workqueue: drop apply_wqattrs_lock()/unlock() wrappers The apply_wqattrs_lock()/unlock() helpers were introduced by commit a0111cf6710b ("workqueue: separate out and refactor the locking of applying attrs") to encapsulate the get_online_cpus() (later cpus_read_lock()) + mutex_lock(&wq_pool_mutex) acquire pair that was duplicated across the apply-attrs paths. Since commit 19af45757383 ("workqueue: Remove cpus_read_lock() from apply_wqattrs_lock()") removed the cpus_read_lock() (pwq creation and installation now operate on wq_online_cpumask, so CPU hotplug no longer needs to be excluded), the wrappers have been one-line forwarders to mutex_lock(&wq_pool_mutex)/mutex_unlock(&wq_pool_mutex). They no longer encode any non-trivial locking rule and obscure the fact that callers just take the existing wq_pool_mutex. This align with the "unnecessary" helpers that got discussed in [1] Inline the eight call sites and remove the wrappers. No functional change. Link: https://lore.kernel.org/all/afs_44-6ToJJVZTn@gmail.com/ [1] Signed-off-by: Breno Leitao Signed-off-by: Tejun Heo --- diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 3d2e3b2ec5283..9adee917e2bb9 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -5300,16 +5300,6 @@ static struct pool_workqueue *alloc_unbound_pwq(struct workqueue_struct *wq, return pwq; } -static void apply_wqattrs_lock(void) -{ - mutex_lock(&wq_pool_mutex); -} - -static void apply_wqattrs_unlock(void) -{ - mutex_unlock(&wq_pool_mutex); -} - /** * wq_calc_pod_cpumask - calculate a wq_attrs' cpumask for a pod * @attrs: the wq_attrs of the default pwq of the target workqueue @@ -5863,7 +5853,7 @@ static struct workqueue_struct *__alloc_workqueue(const char *fmt, * wq_pool_mutex protects the workqueues list, allocations of PWQs, * and the global freeze state. */ - apply_wqattrs_lock(); + mutex_lock(&wq_pool_mutex); if (alloc_and_link_pwqs(wq) < 0) goto err_unlock_free_node_nr_active; @@ -5877,7 +5867,7 @@ static struct workqueue_struct *__alloc_workqueue(const char *fmt, if (wq_online && init_rescuer(wq) < 0) goto err_unlock_destroy; - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); if ((wq->flags & WQ_SYSFS) && workqueue_sysfs_register(wq)) goto err_destroy; @@ -5885,7 +5875,7 @@ static struct workqueue_struct *__alloc_workqueue(const char *fmt, return wq; err_unlock_free_node_nr_active: - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); /* * Failed alloc_and_link_pwqs() may leave pending pwq->release_work, * flushing the pwq_release_worker ensures that the pwq_release_workfn() @@ -5900,7 +5890,7 @@ err_free_wq: kfree(wq); return NULL; err_unlock_destroy: - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); err_destroy: destroy_workqueue(wq); return NULL; @@ -7301,7 +7291,7 @@ static ssize_t wq_nice_store(struct device *dev, struct device_attribute *attr, struct workqueue_attrs *attrs; int ret = -ENOMEM; - apply_wqattrs_lock(); + mutex_lock(&wq_pool_mutex); attrs = wq_sysfs_prep_attrs(wq); if (!attrs) @@ -7314,7 +7304,7 @@ static ssize_t wq_nice_store(struct device *dev, struct device_attribute *attr, ret = -EINVAL; out_unlock: - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); free_workqueue_attrs(attrs); return ret ?: count; } @@ -7340,7 +7330,7 @@ static ssize_t wq_cpumask_store(struct device *dev, struct workqueue_attrs *attrs; int ret = -ENOMEM; - apply_wqattrs_lock(); + mutex_lock(&wq_pool_mutex); attrs = wq_sysfs_prep_attrs(wq); if (!attrs) @@ -7351,7 +7341,7 @@ static ssize_t wq_cpumask_store(struct device *dev, ret = apply_workqueue_attrs_locked(wq, attrs); out_unlock: - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); free_workqueue_attrs(attrs); return ret ?: count; } @@ -7387,13 +7377,13 @@ static ssize_t wq_affn_scope_store(struct device *dev, if (affn < 0) return affn; - apply_wqattrs_lock(); + mutex_lock(&wq_pool_mutex); attrs = wq_sysfs_prep_attrs(wq); if (attrs) { attrs->affn_scope = affn; ret = apply_workqueue_attrs_locked(wq, attrs); } - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); free_workqueue_attrs(attrs); return ret ?: count; } @@ -7418,13 +7408,13 @@ static ssize_t wq_affinity_strict_store(struct device *dev, if (sscanf(buf, "%d", &v) != 1) return -EINVAL; - apply_wqattrs_lock(); + mutex_lock(&wq_pool_mutex); attrs = wq_sysfs_prep_attrs(wq); if (attrs) { attrs->affn_strict = (bool)v; ret = apply_workqueue_attrs_locked(wq, attrs); } - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); free_workqueue_attrs(attrs); return ret ?: count; } @@ -7465,12 +7455,12 @@ static int workqueue_set_unbound_cpumask(cpumask_var_t cpumask) cpumask_and(cpumask, cpumask, cpu_possible_mask); if (!cpumask_empty(cpumask)) { ret = 0; - apply_wqattrs_lock(); + mutex_lock(&wq_pool_mutex); if (!cpumask_equal(cpumask, wq_unbound_cpumask)) ret = workqueue_apply_unbound_cpumask(cpumask); if (!ret) cpumask_copy(wq_requested_unbound_cpumask, cpumask); - apply_wqattrs_unlock(); + mutex_unlock(&wq_pool_mutex); } return ret;