[PATCH 11/33] cpuset: Provide lockdep check for cpuset lock held
From: Frederic Weisbecker <frederic@kernel.org>
Date: 2025-10-13 20:33:25
Also in:
cgroups, linux-arm-kernel, linux-block, linux-mm, linux-pci, lkml
Subsystem:
control group (cgroup), control group - cpuset, the rest · Maintainers:
Tejun Heo, Johannes Weiner, Michal Koutný, Waiman Long, Linus Torvalds
cpuset modifies partitions, including isolated, while holding the cpuset mutex. This means that holding the cpuset mutex is safe to synchronize against housekeeping cpumask changes. Provide a lockdep check to validate that. Signed-off-by: Frederic Weisbecker <frederic@kernel.org> --- include/linux/cpuset.h | 2 ++ kernel/cgroup/cpuset.c | 7 +++++++ 2 files changed, 9 insertions(+)
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 2ddb256187b5..051d36fec578 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h@@ -18,6 +18,8 @@ #include <linux/mmu_context.h> #include <linux/jump_label.h> +extern bool lockdep_is_cpuset_held(void); + #ifdef CONFIG_CPUSETS /*
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index 8595f1eadf23..aa1ac7bcf2ea 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c@@ -279,6 +279,13 @@ void cpuset_full_unlock(void) cpus_read_unlock(); } +#ifdef CONFIG_LOCKDEP +bool lockdep_is_cpuset_held(void) +{ + return lockdep_is_held(&cpuset_mutex); +} +#endif + static DEFINE_SPINLOCK(callback_lock); void cpuset_callback_lock_irq(void)
--
2.51.0