Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752697AbZLNMcY (ORCPT ); Mon, 14 Dec 2009 07:32:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750997AbZLNMcX (ORCPT ); Mon, 14 Dec 2009 07:32:23 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:35340 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750875AbZLNMcW (ORCPT ); Mon, 14 Dec 2009 07:32:22 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Rik van Riel Subject: [PATCH 7/8] Use TASK_KILLABLE instead TASK_UNINTERRUPTIBLE 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 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 X-Mailer: Becky! ver. 2.50.07 [ja] Date: Mon, 14 Dec 2009 21:32:18 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1939 Lines: 65 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 from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/