From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932451Ab0LHBCY (ORCPT ); Tue, 7 Dec 2010 20:02:24 -0500 Received: from kroah.org ([198.145.64.141]:33422 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757326Ab0LHBCR (ORCPT ); Tue, 7 Dec 2010 20:02:17 -0500 X-Mailbox-Line: From gregkh@clark.site Tue Dec 7 16:57:38 2010 Message-Id: <20101208005738.570723192@clark.site> User-Agent: quilt/0.48-11.2 Date: Tue, 07 Dec 2010 16:59:08 -0800 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Ken Chen Subject: [171/289] latencytop: fix per task accumulator In-Reply-To: <20101208005821.GA2922@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.36-stable review patch. If anyone has any objections, please let us know. ------------------ From: Ken Chen commit 38715258aa2e8cd94bd4aafadc544e5104efd551 upstream. Per task latencytop accumulator prematurely terminates due to erroneous placement of latency_record_count. It should be incremented whenever a new record is allocated instead of increment on every latencytop event. Also fix search iterator to only search known record events instead of blindly searching all pre-allocated space. Signed-off-by: Ken Chen Reviewed-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- kernel/latencytop.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) --- a/kernel/latencytop.c +++ b/kernel/latencytop.c @@ -194,14 +194,7 @@ __account_scheduler_latency(struct task_ account_global_scheduler_latency(tsk, &lat); - /* - * short term hack; if we're > 32 we stop; future we recycle: - */ - tsk->latency_record_count++; - if (tsk->latency_record_count >= LT_SAVECOUNT) - goto out_unlock; - - for (i = 0; i < LT_SAVECOUNT; i++) { + for (i = 0; i < tsk->latency_record_count; i++) { struct latency_record *mylat; int same = 1; @@ -227,8 +220,14 @@ __account_scheduler_latency(struct task_ } } + /* + * short term hack; if we're > 32 we stop; future we recycle: + */ + if (tsk->latency_record_count >= LT_SAVECOUNT) + goto out_unlock; + /* Allocated a new one: */ - i = tsk->latency_record_count; + i = tsk->latency_record_count++; memcpy(&tsk->latency_record[i], &lat, sizeof(struct latency_record)); out_unlock: