From 78daf80bdbcaea2e2c65462d6f374421e002cac2 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Fri, 2 Dec 2011 14:06:48 +1100 Subject: [PATCH] thp: reduce khugepaged freezing latency Use wait_event_freezable_timeout() instead of schedule_timeout_interruptible() to avoid missing freezer wakeups. A try_to_freeze() would have been needed in the khugepaged_alloc_hugepage tight loop too in case of the allocation failing repeatedly, and wait_event_freezable_timeout will provide it too. khugepaged would still freeze just fine by trying again the next minute but it's better if it freezes immediately. Reported-by: Jiri Slaby Signed-off-by: Andrea Arcangeli Tested-by: Jiri Slaby Cc: Tejun Heo Cc: Oleg Nesterov Cc: "Srivatsa S. Bhat" Cc: "Rafael J. Wysocki" --- mm/huge_memory.c | 16 ++++------------ 1 file changed, 4 insertions(+), 12 deletions(-) diff --git a/mm/huge_memory.c b/mm/huge_memory.c index 4298abaae153..36b3d988b4ef 100644 --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -2259,12 +2259,8 @@ static void khugepaged_do_scan(struct page **hpage) static void khugepaged_alloc_sleep(void) { - DEFINE_WAIT(wait); - add_wait_queue(&khugepaged_wait, &wait); - schedule_timeout_interruptible( - msecs_to_jiffies( - khugepaged_alloc_sleep_millisecs)); - remove_wait_queue(&khugepaged_wait, &wait); + wait_event_freezable_timeout(khugepaged_wait, false, + msecs_to_jiffies(khugepaged_alloc_sleep_millisecs)); } #ifndef CONFIG_NUMA @@ -2313,14 +2309,10 @@ static void khugepaged_loop(void) if (unlikely(kthread_should_stop())) break; if (khugepaged_has_work()) { - DEFINE_WAIT(wait); if (!khugepaged_scan_sleep_millisecs) continue; - add_wait_queue(&khugepaged_wait, &wait); - schedule_timeout_interruptible( - msecs_to_jiffies( - khugepaged_scan_sleep_millisecs)); - remove_wait_queue(&khugepaged_wait, &wait); + wait_event_freezable_timeout(khugepaged_wait, false, + msecs_to_jiffies(khugepaged_scan_sleep_millisecs)); } else if (khugepaged_enabled()) wait_event_freezable(khugepaged_wait, khugepaged_wait_event()); -- 2.39.5