[PATCH] out of memory notifier

[pandora-kernel.git] / mm / oom_kill.c

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index d46ed0f..7d05684 100644 (file)
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -21,6 +21,8 @@
 #include <linux/timex.h>
 #include <linux/jiffies.h>
 #include <linux/cpuset.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
 
 int sysctl_panic_on_oom;
 /* #define DEBUG */
@@ -225,7 +227,7 @@ static struct task_struct *select_bad_process(unsigned long *ppoints)
  * CAP_SYS_RAW_IO set, send SIGTERM instead (but it's unlikely that
  * we select a process with CAP_SYS_RAW_IO set).
  */
-static void __oom_kill_task(task_t *p, const char *message)
+static void __oom_kill_task(struct task_struct *p, const char *message)
 {
        if (p->pid == 1) {
                WARN_ON(1);
@@ -255,10 +257,10 @@ static void __oom_kill_task(task_t *p, const char *message)
        force_sig(SIGKILL, p);
 }
 
-static int oom_kill_task(task_t *p, const char *message)
+static int oom_kill_task(struct task_struct *p, const char *message)
 {
        struct mm_struct *mm;
-       task_t * g, * q;
+       struct task_struct *g, *q;
 
        mm = p->mm;
 
@@ -306,6 +308,20 @@ static int oom_kill_process(struct task_struct *p, unsigned long points,
        return oom_kill_task(p, message);
 }
 
+static BLOCKING_NOTIFIER_HEAD(oom_notify_list);
+
+int register_oom_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_register(&oom_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(register_oom_notifier);
+
+int unregister_oom_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_unregister(&oom_notify_list, nb);
+}
+EXPORT_SYMBOL_GPL(unregister_oom_notifier);
+
 /**
  * out_of_memory - kill the "best" process when we run out of memory
  *
@@ -316,8 +332,14 @@ static int oom_kill_process(struct task_struct *p, unsigned long points,
  */
 void out_of_memory(struct zonelist *zonelist, gfp_t gfp_mask, int order)
 {
-       task_t *p;
+       struct task_struct *p;
        unsigned long points = 0;
+       unsigned long freed = 0;
+
+       blocking_notifier_call_chain(&oom_notify_list, 0, &freed);
+       if (freed > 0)
+               /* Got some memory back in the last second. */
+               return;
 
        if (printk_ratelimit()) {
                printk("oom-killer: gfp_mask=0x%x, order=%d\n",