mm, oom: fix race when specifying a thread as the oom origin

[mirror_ubuntu-artful-kernel.git] / include / linux / oom.h

diff --git a/include/linux/oom.h b/include/linux/oom.h
index d36a8221f58be3ac51ae37730469c380a433149e..da60007075b509b864d386b3d9092c77aec97c64 100644 (file)
--- a/include/linux/oom.h
+++ b/include/linux/oom.h
@@ -1,18 +1,11 @@
 #ifndef __INCLUDE_LINUX_OOM_H
 #define __INCLUDE_LINUX_OOM_H
 
-/*
- * /proc/<pid>/oom_score_adj set to OOM_SCORE_ADJ_MIN disables oom killing for
- * pid.
- */
-#define OOM_SCORE_ADJ_MIN      (-1000)
-#define OOM_SCORE_ADJ_MAX      1000
-
-#ifdef __KERNEL__
 
 #include <linux/sched.h>
 #include <linux/types.h>
 #include <linux/nodemask.h>
+#include <uapi/linux/oom.h>
 
 struct zonelist;
 struct notifier_block;
@@ -36,8 +29,23 @@ enum oom_scan_t {
        OOM_SCAN_SELECT,        /* always select this thread first */
 };
 
-extern void compare_swap_oom_score_adj(int old_val, int new_val);
-extern int test_set_oom_score_adj(int new_val);
+/* Thread is the potential origin of an oom condition; kill first on oom */
+#define OOM_FLAG_ORIGIN                ((__force oom_flags_t)0x1)
+
+static inline void set_current_oom_origin(void)
+{
+       current->signal->oom_flags |= OOM_FLAG_ORIGIN;
+}
+
+static inline void clear_current_oom_origin(void)
+{
+       current->signal->oom_flags &= ~OOM_FLAG_ORIGIN;
+}
+
+static inline bool oom_task_origin(const struct task_struct *p)
+{
+       return !!(p->signal->oom_flags & OOM_FLAG_ORIGIN);
+}
 
 extern unsigned long oom_badness(struct task_struct *p,
                struct mem_cgroup *memcg, const nodemask_t *nodemask,
@@ -56,8 +64,6 @@ extern void check_panic_on_oom(enum oom_constraint constraint, gfp_t gfp_mask,
 extern enum oom_scan_t oom_scan_process_thread(struct task_struct *task,
                unsigned long totalpages, const nodemask_t *nodemask,
                bool force_kill);
-extern void mem_cgroup_out_of_memory(struct mem_cgroup *memcg, gfp_t gfp_mask,
-                                    int order);
 
 extern void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask,
                int order, nodemask_t *mask, bool force_kill);
@@ -82,5 +88,4 @@ extern struct task_struct *find_lock_task_mm(struct task_struct *p);
 extern int sysctl_oom_dump_tasks;
 extern int sysctl_oom_kill_allocating_task;
 extern int sysctl_panic_on_oom;
-#endif /* __KERNEL__*/
 #endif /* _INCLUDE_LINUX_OOM_H */