Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754117AbZLNMaZ (ORCPT ); Mon, 14 Dec 2009 07:30:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750888AbZLNMaY (ORCPT ); Mon, 14 Dec 2009 07:30:24 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:35270 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750793AbZLNMaX (ORCPT ); Mon, 14 Dec 2009 07:30:23 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Rik van Riel Subject: [PATCH 4/8] Use prepare_to_wait_exclusive() instead prepare_to_wait() 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: <20091214212936.BBBA.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 21:30:19 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1305 Lines: 40 if we don't use exclusive queue, wake_up() function wake _all_ waited task. This is simply cpu wasting. Signed-off-by: KOSAKI Motohiro --- mm/vmscan.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/vmscan.c b/mm/vmscan.c index e0cb834..3562a2d 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -1618,7 +1618,7 @@ static int shrink_zone_begin(struct zone *zone, struct scan_control *sc) * we would just make things slower. */ for (;;) { - prepare_to_wait(wq, &wait, TASK_UNINTERRUPTIBLE); + prepare_to_wait_exclusive(wq, &wait, TASK_UNINTERRUPTIBLE); if (atomic_read(&zone->concurrent_reclaimers) <= max_zone_concurrent_reclaimers) @@ -1632,7 +1632,7 @@ static int shrink_zone_begin(struct zone *zone, struct scan_control *sc) */ if (zone_watermark_ok(zone, sc->order, low_wmark_pages(zone), 0, 0)) { - wake_up(wq); + wake_up_all(wq); finish_wait(wq, &wait); sc->nr_reclaimed += sc->nr_to_reclaim; return -ERESTARTSYS; -- 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/