[PATCH] oom: less memdie

[linux-2.6.git] / mm / oom_kill.c

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 2e3ce3a928b97dd8eeb54b42fb6f363d15a6d2ae..223d9ccb7d64b6b28f5642ba3ab12629a170419a 100644 (file)
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -264,7 +264,7 @@ static struct task_struct *select_bad_process(unsigned long *ppoints)
  * flag though it's unlikely that  we select a process with CAP_SYS_RAW_IO
  * set.
  */
-static void __oom_kill_task(struct task_struct *p, const char *message)
+static void __oom_kill_task(struct task_struct *p, int verbose)
 {
        if (is_init(p)) {
                WARN_ON(1);
@@ -278,10 +278,8 @@ static void __oom_kill_task(struct task_struct *p, const char *message)
                return;
        }
 
-       if (message) {
-               printk(KERN_ERR "%s: Killed process %d (%s).\n",
-                               message, p->pid, p->comm);
-       }
+       if (verbose)
+               printk(KERN_ERR "Killed process %d (%s)\n", p->pid, p->comm);
 
        /*
         * We give our sacrificial lamb high priority and access to
@@ -294,7 +292,7 @@ static void __oom_kill_task(struct task_struct *p, const char *message)
        force_sig(SIGKILL, p);
 }
 
-static int oom_kill_task(struct task_struct *p, const char *message)
+static int oom_kill_task(struct task_struct *p)
 {
        struct mm_struct *mm;
        struct task_struct *g, *q;
@@ -313,15 +311,25 @@ static int oom_kill_task(struct task_struct *p, const char *message)
        if (mm == NULL)
                return 1;
 
-       __oom_kill_task(p, message);
+       /*
+        * Don't kill the process if any threads are set to OOM_DISABLE
+        */
+       do_each_thread(g, q) {
+               if (q->mm == mm && p->oomkilladj == OOM_DISABLE)
+                       return 1;
+       } while_each_thread(g, q);
+
+       __oom_kill_task(p, 1);
+
        /*
         * kill all processes that share the ->mm (i.e. all threads),
-        * but are in a different thread group
+        * but are in a different thread group. Don't let them have access
+        * to memory reserves though, otherwise we might deplete all memory.
         */
-       do_each_thread(g, q)
+       do_each_thread(g, q) {
                if (q->mm == mm && q->tgid != p->tgid)
-                       __oom_kill_task(q, message);
-       while_each_thread(g, q);
+                       force_sig(SIGKILL, p);
+       } while_each_thread(g, q);
 
        return 0;
 }
@@ -337,21 +345,22 @@ static int oom_kill_process(struct task_struct *p, unsigned long points,
         * its children or threads, just set TIF_MEMDIE so it can die quickly
         */
        if (p->flags & PF_EXITING) {
-               __oom_kill_task(p, NULL);
+               __oom_kill_task(p, 0);
                return 0;
        }
 
-       printk(KERN_ERR "Out of Memory: Kill process %d (%s) score %li"
-                       " and children.\n", p->pid, p->comm, points);
+       printk(KERN_ERR "%s: kill process %d (%s) score %li or a child\n",
+                                       message, p->pid, p->comm, points);
+
        /* Try to kill a child first */
        list_for_each(tsk, &p->children) {
                c = list_entry(tsk, struct task_struct, sibling);
                if (c->mm == p->mm)
                        continue;
-               if (!oom_kill_task(c, message))
+               if (!oom_kill_task(c))
                        return 0;
        }
-       return oom_kill_task(p, message);
+       return oom_kill_task(p);
 }
 
 static BLOCKING_NOTIFIER_HEAD(oom_notify_list);