From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933505Ab1DNRyH (ORCPT ); Thu, 14 Apr 2011 13:54:07 -0400 Received: from mail.windriver.com ([147.11.1.11]:38442 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933357Ab1DNRrE (ORCPT ); Thu, 14 Apr 2011 13:47:04 -0400 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Ken Chen , Andrew Morton , Linus Torvalds , Paul Gortmaker Subject: [34-longterm 064/209] latencytop: fix per task accumulator Date: Thu, 14 Apr 2011 13:41:34 -0400 Message-Id: <1302803039-9400-65-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1302803039-9400-1-git-send-email-paul.gortmaker@windriver.com> References: <1302803039-9400-1-git-send-email-paul.gortmaker@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Ken Chen ===================================================================== | This is a commit scheduled for the next v2.6.34 longterm release. | | If you see a problem with using this for longterm, please comment.| ===================================================================== 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: Paul Gortmaker --- kernel/latencytop.c | 17 ++++++++--------- 1 files changed, 8 insertions(+), 9 deletions(-) diff --git a/kernel/latencytop.c b/kernel/latencytop.c index 877fb30..17110a4 100644 --- a/kernel/latencytop.c +++ b/kernel/latencytop.c @@ -194,14 +194,7 @@ __account_scheduler_latency(struct task_struct *tsk, int usecs, int inter) 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_struct *tsk, int usecs, int inter) } } + /* + * 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: -- 1.7.4.4