From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id 9A6416B0062 for ; Mon, 14 Dec 2009 07:32:24 -0500 (EST) Received: from m3.gw.fujitsu.co.jp ([10.0.50.73]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nBECWKiI003985 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Mon, 14 Dec 2009 21:32:20 +0900 Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 26D4345DE50 for ; Mon, 14 Dec 2009 21:32:20 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 014D345DE4D for ; Mon, 14 Dec 2009 21:32:20 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id DCA8C1DB8041 for ; Mon, 14 Dec 2009 21:32:19 +0900 (JST) Received: from m107.s.css.fujitsu.com (m107.s.css.fujitsu.com [10.249.87.107]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 913B51DB803C for ; Mon, 14 Dec 2009 21:32:19 +0900 (JST) From: KOSAKI Motohiro Subject: [PATCH 7/8] Use TASK_KILLABLE instead TASK_UNINTERRUPTIBLE In-Reply-To: <20091214210823.BBAE.A69D9226@jp.fujitsu.com> References: <20091211164651.036f5340@annuminas.surriel.com> <20091214210823.BBAE.A69D9226@jp.fujitsu.com> Message-Id: <20091214213145.BBC3.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Mon, 14 Dec 2009 21:32:18 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Rik van Riel Cc: kosaki.motohiro@jp.fujitsu.com, lwoodman@redhat.com, akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, minchan.kim@gmail.com List-ID: When fork bomb invoke OOM Killer, almost task might start to reclaim and sleep on shrink_zone_begin(). if we use TASK_UNINTERRUPTIBLE, OOM killer can't kill such task. it mean we never recover from fork bomb. This patch fixes it. Signed-off-by: KOSAKI Motohiro --- mm/vmscan.c | 20 +++++++++++++------- 1 files changed, 13 insertions(+), 7 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index bf229d3..e537361 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1618,7 +1618,10 @@ static int shrink_zone_begin(struct zone *zone, struct scan_control *sc) * we would just make things slower. */ for (;;) { - prepare_to_wait_exclusive(wq, &wait, TASK_UNINTERRUPTIBLE); + prepare_to_wait_exclusive(wq, &wait, TASK_KILLABLE); + + if (fatal_signal_pending(current)) + goto stop_reclaim; if (atomic_read(&zone->concurrent_reclaimers) <= max_zone_concurrent_reclaimers) @@ -1631,18 +1634,21 @@ static int shrink_zone_begin(struct zone *zone, struct scan_control *sc) * break out of the loop and go back to the allocator. */ if (zone_watermark_ok(zone, sc->order, low_wmark_pages(zone), - 0, 0)) { - wake_up_all(wq); - finish_wait(wq, &wait); - sc->nr_reclaimed += sc->nr_to_reclaim; - return -ERESTARTSYS; - } + 0, 0)) + goto found_lots_memory; } finish_wait(wq, &wait); out: atomic_inc(&zone->concurrent_reclaimers); return 0; + + found_lots_memory: + wake_up_all(wq); + stop_reclaim: + finish_wait(wq, &wait); + sc->nr_reclaimed += sc->nr_to_reclaim; + return -ERESTARTSYS; } static void shrink_zone_end(struct zone *zone, struct scan_control *sc) -- 1.6.5.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org