mm, oom: remove task_lock protecting comm printing
The oom killer takes task_lock() in a couple of places solely to protect
printing the task's comm.
A process's comm, including current's comm, may change due to
/proc/pid/comm or PR_SET_NAME.
The comm will always be NULL-terminated, so the worst race scenario would
only be during update. We can tolerate a comm being printed that is in
the middle of an update to avoid taking the lock.
Other locations in the kernel have already dropped task_lock() when
printing comm, so this is consistent.
Signed-off-by: David Rientjes <rientjes@google.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h
index 1b35799..5a13119 100644
--- a/include/linux/cpuset.h
+++ b/include/linux/cpuset.h
@@ -93,7 +93,7 @@
extern void rebuild_sched_domains(void);
-extern void cpuset_print_task_mems_allowed(struct task_struct *p);
+extern void cpuset_print_current_mems_allowed(void);
/*
* read_mems_allowed_begin is required when making decisions involving
@@ -219,7 +219,7 @@
partition_sched_domains(1, NULL, NULL);
}
-static inline void cpuset_print_task_mems_allowed(struct task_struct *p)
+static inline void cpuset_print_current_mems_allowed(void)
{
}