Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759574Ab3GaKjc (ORCPT ); Wed, 31 Jul 2013 06:39:32 -0400 Received: from szxga03-in.huawei.com ([119.145.14.66]:10794 "EHLO szxga03-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755572Ab3GaKja (ORCPT ); Wed, 31 Jul 2013 06:39:30 -0400 Message-ID: <51F8E922.3070008@huawei.com> Date: Wed, 31 Jul 2013 18:38:26 +0800 From: "zhangwei(Jovi)" User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Andrew Morton , Ingo Molnar CC: "linux-kernel@vger.kernel.org" , Dan Carpenter , Steven Rostedt , Jens Axboe , Al Viro , Eric Dumazet Subject: Re: [PATCH] relay: fix timer madness References: <51F8E06C.1010408@huawei.com> In-Reply-To: <51F8E06C.1010408@huawei.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.66.58.241] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1585 Lines: 41 On 2013/7/31 18:01, zhangwei(Jovi) wrote: > From: Ingo Molnar > > When I'm using ktap script to tracing all event tracepoints by relay > transport, without this patch, the system will hang in few seconds. > > I found the original patch discussion in 2007. > http://marc.info/?l=linux-kernel&m=118544794717162&w=2 > (In that mail thread, the patch didn't fix that problem, but it fix > the problem I encountered now) > > Changed from origina patch: > - mod timer interval changed from jiffies+1 to HZ/10, as Ingo suggested. > - mod timer interval changed from HZ/10 to jiffies + HZ/10, suggested > by Dan Carpenter, since mod_timer() takes an offset for interval. > > Original patch changelog from Ingo in 2007: > > Remove timer calls (!!!) from deep within the tracing infrastructure. > This was totally bogus code that can cause lockups and worse. > Poll the buffer every 2 jiffies for now. > > Signed-off-by: Ingo Molnar > Signed-off-by: "zhangwei(Jovi)" > Cc: Dan Carpenter > Cc: Steven Rostedt > Cc: Jens Axboe > Cc: Al Viro > Cc: Eric Dumazet > --- Hi Andrew, How about this patch? this version folded the suggestion from Ingo and Dan. jovi -- 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/