[PATCH] oom_kill_task(): cleanup ->mm checks

- It is not possible to have task->mm == &init_mm.

- task_lock() buys nothing for 'if (!p->mm)' check.

Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 2 insertions, 5 deletions

diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index 991bf0cf4778..a5493a3b4851 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -260,14 +260,11 @@ static void __oom_kill_task(struct task_struct *p, const char *message)
                 return;
         }
 
-        task_lock(p);
-        if (!p->mm || p->mm == &init_mm) {
+        if (!p->mm) {
                 WARN_ON(1);
                 printk(KERN_WARNING "tried to kill an mm-less task!\n");
-                task_unlock(p);
                 return;
         }
-        task_unlock(p);
 
         if (message) {
                 printk(KERN_ERR "%s: Killed process %d (%s).\n",
@@ -301,7 +298,7 @@ static int oom_kill_task(struct task_struct *p, const char *message)
          * However, this is of no concern to us.
          */
 
-        if (mm == NULL || mm == &init_mm)
+        if (mm == NULL)
                 return 1;
 
         __oom_kill_task(p, message);