1 files changed, 52 insertions, 0 deletions
diff --git a/include/linux/vmpressure.h b/include/linux/vmpressure.h
new file mode 100644
index 000000000..6a2f51ebb
--- /dev/null
+++ b/include/linux/vmpressure.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_VMPRESSURE_H
+#define __LINUX_VMPRESSURE_H
+
+#include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/workqueue.h>
+#include <linux/gfp.h>
+#include <linux/types.h>
+#include <linux/cgroup.h>
+#include <linux/eventfd.h>
+
+struct vmpressure {
+	unsigned long scanned;
+	unsigned long reclaimed;
+
+	unsigned long tree_scanned;
+	unsigned long tree_reclaimed;
+	/* The lock is used to keep the scanned/reclaimed above in sync. */
+	spinlock_t sr_lock;
+
+	/* The list of vmpressure_event structs. */
+	struct list_head events;
+	/* Have to grab the lock on events traversal or modifications. */
+	struct mutex events_lock;
+
+	struct work_struct work;
+};
+
+struct mem_cgroup;
+
+#ifdef CONFIG_MEMCG
+extern void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, bool tree,
+		       unsigned long scanned, unsigned long reclaimed);
+extern void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg, int prio);
+
+extern void vmpressure_init(struct vmpressure *vmpr);
+extern void vmpressure_cleanup(struct vmpressure *vmpr);
+extern struct vmpressure *memcg_to_vmpressure(struct mem_cgroup *memcg);
+extern struct mem_cgroup *vmpressure_to_memcg(struct vmpressure *vmpr);
+extern int vmpressure_register_event(struct mem_cgroup *memcg,
+				     struct eventfd_ctx *eventfd,
+				     const char *args);
+extern void vmpressure_unregister_event(struct mem_cgroup *memcg,
+					struct eventfd_ctx *eventfd);
+#else
+static inline void vmpressure(gfp_t gfp, struct mem_cgroup *memcg, bool tree,
+			      unsigned long scanned, unsigned long reclaimed) {}
+static inline void vmpressure_prio(gfp_t gfp, struct mem_cgroup *memcg,
+				   int prio) {}
+#endif /* CONFIG_MEMCG */
+#endif /* __LINUX_VMPRESSURE_H */