From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with SMTP id B456F6B0044 for ; Mon, 14 Dec 2009 07:30:29 -0500 (EST) Received: from m4.gw.fujitsu.co.jp ([10.0.50.74]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id nBECUK4Q003099 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Mon, 14 Dec 2009 21:30:21 +0900 Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 8A4B045DE60 for ; Mon, 14 Dec 2009 21:30:20 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 68B0C45DE4D for ; Mon, 14 Dec 2009 21:30:20 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 34CCE1DB803B for ; Mon, 14 Dec 2009 21:30:20 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id E50C41DB8037 for ; Mon, 14 Dec 2009 21:30:19 +0900 (JST) From: KOSAKI Motohiro Subject: [PATCH 4/8] Use prepare_to_wait_exclusive() instead prepare_to_wait() 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 Date: Mon, 14 Dec 2009 21:30:19 +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: 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, 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