From 878aee7d6b5504e01b9caffce080e792b6b8d090 Mon Sep 17 00:00:00 2001 From: Andrea Arcangeli Date: Thu, 13 Jan 2011 15:47:10 -0800 Subject: thp: freeze khugepaged and ksmd It's unclear why schedule friendly kernel threads can't be taken away by the CPU through the scheduler itself. It's safer to stop them as they can trigger memory allocation, if kswapd also freezes itself to avoid generating I/O they have too. Signed-off-by: Andrea Arcangeli Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/ksm.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'mm/ksm.c') diff --git a/mm/ksm.c b/mm/ksm.c index 5e7d5d3..e2b0afd 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include "internal.h" @@ -1365,7 +1366,7 @@ static void ksm_do_scan(unsigned int scan_npages) struct rmap_item *rmap_item; struct page *uninitialized_var(page); - while (scan_npages--) { + while (scan_npages-- && likely(!freezing(current))) { cond_resched(); rmap_item = scan_get_next_rmap_item(&page); if (!rmap_item) @@ -1383,6 +1384,7 @@ static int ksmd_should_run(void) static int ksm_scan_thread(void *nothing) { + set_freezable(); set_user_nice(current, 5); while (!kthread_should_stop()) { @@ -1391,11 +1393,13 @@ static int ksm_scan_thread(void *nothing) ksm_do_scan(ksm_thread_pages_to_scan); mutex_unlock(&ksm_thread_mutex); + try_to_freeze(); + if (ksmd_should_run()) { schedule_timeout_interruptible( msecs_to_jiffies(ksm_thread_sleep_millisecs)); } else { - wait_event_interruptible(ksm_thread_wait, + wait_event_freezable(ksm_thread_wait, ksmd_should_run() || kthread_should_stop()); } } -- cgit v1.1