From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754097Ab3F0Tbk (ORCPT ); Thu, 27 Jun 2013 15:31:40 -0400 Received: from ns1.pc-advies.be ([83.149.101.17]:52689 "EHLO spo001.leaseweb.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753796Ab3F0Tbj (ORCPT ); Thu, 27 Jun 2013 15:31:39 -0400 Date: Thu, 27 Jun 2013 21:31:38 +0200 From: Wim Van Sebroeck To: anish kumar Cc: linux@roeck-us.net, linux-watchdog@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] [RFC]Watchdog:core: constant pinging until userspace timesout when delay very less Message-ID: <20130627193138.GB30433@spo001.leaseweb.com> References: <1370167987-14252-1-git-send-email-anish198519851985@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1370167987-14252-1-git-send-email-anish198519851985@gmail.com> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Anish, > Certain watchdog drivers use a timer to keep kicking the watchdog at > a rate of 0.5s (HZ/2) untill userspace times out.They do this as > we can't guarantee that watchdog will be pinged fast enough > for all system loads, especially if timeout is configured for > less than or equal to 1 second(basically small values). > > As suggested by Wim Van Sebroeck & Guenter Roeck we should > add this functionality of individual watchdog drivers in the core > watchdog core. Have you considered the effect this change has on all watchdog drivers that don't need a timer? Kind regards, Wim.