[PATCH 1/4] mm: introduce zone lock wrappers

[Dmitry Ilvokhin <d@ilvokhin.com>]

Add thin wrappers around zone lock acquire/release operations. This
prepares the code for future tracepoint instrumentation without
modifying individual call sites.

Centralizing zone lock operations behind wrappers allows future
instrumentation or debugging hooks to be added without touching
all users.

No functional change intended. The wrappers are introduced in
preparation for subsequent patches and are not yet used.

Signed-off-by: Dmitry Ilvokhin <d@ilvokhin.com>
---
 MAINTAINERS               |  1 +
 include/linux/zone_lock.h | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)
 create mode 100644 include/linux/zone_lock.h

diff --git a/MAINTAINERS b/MAINTAINERS
index b4088f7290be..680c9ae02d7e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -16498,6 +16498,7 @@ F:	include/linux/pgtable.h
 F:	include/linux/ptdump.h
 F:	include/linux/vmpressure.h
 F:	include/linux/vmstat.h
+F:	include/linux/zone_lock.h
 F:	kernel/fork.c
 F:	mm/Kconfig
 F:	mm/debug.c
diff --git a/include/linux/zone_lock.h b/include/linux/zone_lock.h
new file mode 100644
index 000000000000..c531e26280e6
--- /dev/null
+++ b/include/linux/zone_lock.h
@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_ZONE_LOCK_H
+#define _LINUX_ZONE_LOCK_H
+
+#include <linux/mmzone.h>
+#include <linux/spinlock.h>
+
+static inline void zone_lock_init(struct zone *zone)
+{
+	spin_lock_init(&zone->lock);
+}
+
+#define zone_lock_irqsave(zone, flags)				\
+do {								\
+	spin_lock_irqsave(&(zone)->lock, flags);		\
+} while (0)
+
+#define zone_trylock_irqsave(zone, flags)			\
+({								\
+	spin_trylock_irqsave(&(zone)->lock, flags);		\
+})
+
+static inline void zone_unlock_irqrestore(struct zone *zone, unsigned long flags)
+{
+	spin_unlock_irqrestore(&zone->lock, flags);
+}
+
+static inline void zone_lock_irq(struct zone *zone)
+{
+	spin_lock_irq(&zone->lock);
+}
+
+static inline void zone_unlock_irq(struct zone *zone)
+{
+	spin_unlock_irq(&zone->lock);
+}
+
+#endif /* _LINUX_ZONE_LOCK_H */
-- 
2.47.3