[PATCH V10 2/7] locking/percpu-rwsem: Add guard support

kan.liang
2025-03-14T17:26:51Z

From: "Peter Zijlstra (Intel)" <peterz@infradead.org>

To simplify the usage of the percpu rw semaphore.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: linux-mm@kvack.org
---

No changes since V9

include/linux/percpu-rwsem.h | 8 ++++++++
1 file changed, 8 insertions(+)

diff --git a/include/linux/percpu-rwsem.h b/include/linux/percpu-rwsem.h
index c012df33a9f0..af7d75ede619 100644
--- a/include/linux/percpu-rwsem.h
+++ b/include/linux/percpu-rwsem.h
@@ -8,6 +8,7 @@
#include <linux/wait.h>
#include <linux/rcu_sync.h>
#include <linux/lockdep.h>
+#include <linux/cleanup.h>

struct percpu_rw_semaphore {
struct rcu_sync rss;
@@ -125,6 +126,13 @@ extern bool percpu_is_read_locked(struct percpu_rw_semaphore *);
extern void percpu_down_write(struct percpu_rw_semaphore *);
extern void percpu_up_write(struct percpu_rw_semaphore *);

+DEFINE_GUARD(percpu_read, struct percpu_rw_semaphore *,
+ percpu_down_read(_T), percpu_up_read(_T))
+DEFINE_GUARD_COND(percpu_read, _try, percpu_down_read_trylock(_T))
+
+DEFINE_GUARD(percpu_write, struct percpu_rw_semaphore *,
+ percpu_down_write(_T), percpu_up_write(_T))
+
static inline bool percpu_is_write_locked(struct percpu_rw_semaphore *sem)
{
return atomic_read(&sem->block);
--
2.38.1