summaryrefslogtreecommitdiff
path: root/kernel/exit.c
diff options
context:
space:
mode:
authorBalbir Singh <balbir@linux.vnet.ibm.com>2008-10-15 22:01:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-16 11:21:28 -0700
commit9363b9f23c9cc36cc8ef6c05fdf879ee4a96ae92 (patch)
tree482746b06d6fdd8be606de4dff584a3a40054c4c /kernel/exit.c
parent1648993fb05c487947c1cec6307aca29d8002abe (diff)
memrlimit: cgroup mm owner callback changes to add task info
This patch adds an additional field to the mm_owner callbacks. This field is required to get to the mm that changed. Hold mmap_sem in write mode before calling the mm_owner_changed callback [hugh@veritas.com: fix mmap_sem deadlock] Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: Sudhir Kumar <skumar@linux.vnet.ibm.com> Cc: YAMAMOTO Takashi <yamamoto@valinux.co.jp> Cc: Paul Menage <menage@google.com> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Pavel Emelianov <xemul@openvz.org> Cc: Balbir Singh <balbir@linux.vnet.ibm.com> Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Cc: David Rientjes <rientjes@google.com> Cc: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/exit.c')
-rw-r--r--kernel/exit.c9
1 files changed, 4 insertions, 5 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 85a83c831856..0ef4673e351b 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -640,24 +640,23 @@ retry:
assign_new_owner:
BUG_ON(c == p);
get_task_struct(c);
+ read_unlock(&tasklist_lock);
+ down_write(&mm->mmap_sem);
/*
* The task_lock protects c->mm from changing.
* We always want mm->owner->mm == mm
*/
task_lock(c);
- /*
- * Delay read_unlock() till we have the task_lock()
- * to ensure that c does not slip away underneath us
- */
- read_unlock(&tasklist_lock);
if (c->mm != mm) {
task_unlock(c);
+ up_write(&mm->mmap_sem);
put_task_struct(c);
goto retry;
}
cgroup_mm_owner_callbacks(mm->owner, c);
mm->owner = c;
task_unlock(c);
+ up_write(&mm->mmap_sem);
put_task_struct(c);
}
#endif /* CONFIG_MM_OWNER */