oom: add per-mm oom disable count
[pandora-kernel.git] / kernel / fork.c
index c445f8c..e87aaaa 100644 (file)
@@ -65,6 +65,7 @@
 #include <linux/perf_event.h>
 #include <linux/posix-timers.h>
 #include <linux/user-return-notifier.h>
+#include <linux/oom.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -488,6 +489,7 @@ static struct mm_struct * mm_init(struct mm_struct * mm, struct task_struct *p)
        mm->cached_hole_size = ~0UL;
        mm_init_aio(mm);
        mm_init_owner(mm, p);
+       atomic_set(&mm->oom_disable_count, 0);
 
        if (likely(!mm_alloc_pgd(mm))) {
                mm->def_flags = 0;
@@ -741,6 +743,8 @@ good_mm:
        /* Initializing for Swap token stuff */
        mm->token_priority = 0;
        mm->last_interval = 0;
+       if (tsk->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+               atomic_inc(&mm->oom_disable_count);
 
        tsk->mm = mm;
        tsk->active_mm = mm;
@@ -1299,8 +1303,13 @@ bad_fork_cleanup_io:
 bad_fork_cleanup_namespaces:
        exit_task_namespaces(p);
 bad_fork_cleanup_mm:
-       if (p->mm)
+       if (p->mm) {
+               task_lock(p);
+               if (p->signal->oom_score_adj == OOM_SCORE_ADJ_MIN)
+                       atomic_dec(&p->mm->oom_disable_count);
+               task_unlock(p);
                mmput(p->mm);
+       }
 bad_fork_cleanup_signal:
        if (!(clone_flags & CLONE_THREAD))
                free_signal_struct(p->signal);
@@ -1693,6 +1702,10 @@ SYSCALL_DEFINE1(unshare, unsigned long, unshare_flags)
                        active_mm = current->active_mm;
                        current->mm = new_mm;
                        current->active_mm = new_mm;
+                       if (current->signal->oom_score_adj == OOM_SCORE_ADJ_MIN) {
+                               atomic_dec(&mm->oom_disable_count);
+                               atomic_inc(&new_mm->oom_disable_count);
+                       }
                        activate_mm(active_mm, new_mm);
                        new_mm = mm;
                }