[PATCH -rt] memcg: use migrate_disable()/migrate_enable( ) inmemcg_check_events()
From: Yong Zhang
Date: Wed Nov 16 2011 - 04:17:11 EST
Looking at commit 4799401f [memcg: Fix race condition in
memcg_check_events() with this_cpu usage], we just want
to disable migration. So use the right API in -rt. This
will cure below warning.
BUG: sleeping function called from invalid context at linux/kernel/rtmutex.c:645
in_atomic(): 1, irqs_disabled(): 0, pid: 1, name: swapper/0
1 lock held by swapper/0/1:
#0: (&sig->cred_guard_mutex){+.+.+.}, at: [<ffffffff81154c45>] prepare_bprm_creds+0x35/0x80
Pid: 1, comm: swapper/0 Not tainted 3.2.0-rc1-rt2-11311-g3c4c0e7-dirty #10
Call Trace:
[<ffffffff81040c4e>] __might_sleep+0x12e/0x1e0
[<ffffffff815f4d74>] rt_spin_lock+0x24/0x60
[<ffffffff8114506e>] memcg_check_events+0x11e/0x230
[<ffffffff81146c5a>] T.1144+0x8a/0xf0
[<ffffffff81146d16>] __mem_cgroup_commit_charge_lrucare+0x56/0x180
[<ffffffff810430c9>] ? sub_preempt_count+0xa9/0xe0
[<ffffffff81147d08>] mem_cgroup_cache_charge+0xd8/0xe0
[<ffffffff81103a49>] add_to_page_cache_locked+0x49/0x100
[<ffffffff8110344f>] ? find_get_page+0xdf/0x1a0
[<ffffffff81103b22>] add_to_page_cache_lru+0x22/0x50
[<ffffffff81103ca5>] do_read_cache_page+0x75/0x1a0
[<ffffffff812695f0>] ? nfs_follow_link+0xc0/0xc0
[<ffffffff81103e1c>] read_cache_page_async+0x1c/0x20
[<ffffffff81103e2e>] read_cache_page+0xe/0x20
[<ffffffff81269589>] nfs_follow_link+0x59/0xc0
[<ffffffff8115de07>] path_openat+0x2a7/0x470
[<ffffffff8115e0e9>] do_filp_open+0x49/0xa0
[<ffffffff81155b22>] open_exec+0x32/0xf0
[<ffffffff811a3e0b>] load_elf_binary+0x85b/0x1d30
[<ffffffff81096d55>] ? __lock_acquire+0x4f5/0xbf0
[<ffffffff8100a819>] ? native_sched_clock+0x29/0x80
[<ffffffff8108429f>] ? local_clock+0x4f/0x60
[<ffffffff815f4658>] ? rt_spin_lock_slowunlock+0x78/0x80
[<ffffffff81091a39>] ? trace_hardirqs_off_caller+0x29/0x120
[<ffffffff8109119e>] ? put_lock_stats+0xe/0x40
[<ffffffff815f4658>] ? rt_spin_lock_slowunlock+0x78/0x80
[<ffffffff811a35b0>] ? elf_map+0x1d0/0x1d0
[<ffffffff810430c9>] ? sub_preempt_count+0xa9/0xe0
[<ffffffff811a35b0>] ? elf_map+0x1d0/0x1d0
[<ffffffff81154748>] search_binary_handler+0x1c8/0x4b0
[<ffffffff811545d7>] ? search_binary_handler+0x57/0x4b0
[<ffffffff81156876>] do_execve_common+0x276/0x330
[<ffffffff811569ba>] do_execve+0x3a/0x40
[<ffffffff8100bdca>] sys_execve+0x4a/0x80
[<ffffffff815f85e8>] kernel_execve+0x68/0xd0
[<ffffffff81000333>] ? run_init_process+0x23/0x30
[<ffffffff81000398>] init_post+0x58/0xd0
[<ffffffff81b5e6bd>] kernel_init+0x156/0x160
[<ffffffff815f8574>] kernel_thread_helper+0x4/0x10
[<ffffffff810423bc>] ? finish_task_switch+0x8c/0x110
[<ffffffff815f5bab>] ? _raw_spin_unlock_irq+0x3b/0x70
[<ffffffff815f5f61>] ? retint_restore_args+0xe/0xe
[<ffffffff81b5e567>] ? parse_early_options+0x20/0x20
[<ffffffff815f8570>] ? gs_change+0xb/0xb
Signed-off-by: Yong Zhang <yong.zhang0@xxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
---
mm/memcontrol.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6aff93c..afa1954 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -722,7 +722,7 @@ static void __mem_cgroup_target_update(struct mem_cgroup *memcg, int target)
*/
static void memcg_check_events(struct mem_cgroup *memcg, struct page *page)
{
- preempt_disable();
+ migrate_disable();
/* threshold event is triggered in finer grain than soft limit */
if (unlikely(__memcg_event_check(memcg, MEM_CGROUP_TARGET_THRESH))) {
mem_cgroup_threshold(memcg);
@@ -742,7 +742,7 @@ static void memcg_check_events(struct mem_cgroup *memcg, struct page *page)
}
#endif
}
- preempt_enable();
+ migrate_enable();
}
static struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont)
--
1.7.5.4
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/