diff options
authorMichal Hocko <mhocko@suse.cz>2014-02-25 15:01:44 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-02-25 15:25:44 -0800
commit08088cb9ac0a9c28d4cf3efa4f6848a9b053ccfd (patch)
parent9845cbbd113fbb5b769a45d8e88dc47bc12df4e0 (diff)
memcg: change oom_info_lock to mutex
Kirill has reported the following: Task in /test killed as a result of limit of /test memory: usage 10240kB, limit 10240kB, failcnt 51 memory+swap: usage 10240kB, limit 10240kB, failcnt 0 kmem: usage 0kB, limit 18014398509481983kB, failcnt 0 Memory cgroup stats for /test: BUG: sleeping function called from invalid context at kernel/cpu.c:68 in_atomic(): 1, irqs_disabled(): 0, pid: 66, name: memcg_test 2 locks held by memcg_test/66: #0: (memcg_oom_lock#2){+.+...}, at: [<ffffffff81131014>] pagefault_out_of_memory+0x14/0x90 #1: (oom_info_lock){+.+...}, at: [<ffffffff81197b2a>] mem_cgroup_print_oom_info+0x2a/0x390 CPU: 2 PID: 66 Comm: memcg_test Not tainted 3.14.0-rc1-dirty #745 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Bochs 01/01/2011 Call Trace: __might_sleep+0x16a/0x210 get_online_cpus+0x1c/0x60 mem_cgroup_read_stat+0x27/0xb0 mem_cgroup_print_oom_info+0x260/0x390 dump_header+0x88/0x251 ? trace_hardirqs_on+0xd/0x10 oom_kill_process+0x258/0x3d0 mem_cgroup_oom_synchronize+0x656/0x6c0 ? mem_cgroup_charge_common+0xd0/0xd0 pagefault_out_of_memory+0x14/0x90 mm_fault_error+0x91/0x189 __do_page_fault+0x48e/0x580 do_page_fault+0xe/0x10 page_fault+0x22/0x30 which complains that mem_cgroup_read_stat cannot be called from an atomic context but mem_cgroup_print_oom_info takes a spinlock. Change oom_info_lock to a mutex. This was introduced by 947b3dd1a84b ("memcg, oom: lock mem_cgroup_print_oom_info"). Signed-off-by: Michal Hocko <mhocko@suse.cz> Reported-by: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 files changed, 3 insertions, 3 deletions
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 53385cd4e6f0..ce7a8cc7b404 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1687,7 +1687,7 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
* protects memcg_name and makes sure that parallel ooms do not
* interleave
- static DEFINE_SPINLOCK(oom_info_lock);
+ static DEFINE_MUTEX(oom_info_lock);
struct cgroup *task_cgrp;
struct cgroup *mem_cgrp;
static char memcg_name[PATH_MAX];
@@ -1698,7 +1698,7 @@ void mem_cgroup_print_oom_info(struct mem_cgroup *memcg, struct task_struct *p)
if (!p)
- spin_lock(&oom_info_lock);
+ mutex_lock(&oom_info_lock);
mem_cgrp = memcg->css.cgroup;
@@ -1767,7 +1767,7 @@ done:
- spin_unlock(&oom_info_lock);
+ mutex_unlock(&oom_info_lock);