Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752527AbaDYIZG (ORCPT ); Fri, 25 Apr 2014 04:25:06 -0400 Received: from mail-oa0-f50.google.com ([209.85.219.50]:55697 "EHLO mail-oa0-f50.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751779AbaDYIYx (ORCPT ); Fri, 25 Apr 2014 04:24:53 -0400 MIME-Version: 1.0 In-Reply-To: <20140425081830.10258.10979.stgit@srivatsabhat.in.ibm.com> References: <20140425081728.10258.63980.stgit@srivatsabhat.in.ibm.com> <20140425081830.10258.10979.stgit@srivatsabhat.in.ibm.com> Date: Fri, 25 Apr 2014 13:54:52 +0530 Message-ID: Subject: Re: [PATCH 3/3] cpufreq, powernow-k7: Fix double invocation of cpufreq_freq_transition_begin/end From: Viresh Kumar To: "Srivatsa S. Bhat" Cc: "Rafael J. Wysocki" , Meelis Roos , "cpufreq@vger.kernel.org" , "linux-pm@vger.kernel.org" , Linux Kernel Mailing List Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 25 April 2014 13:48, Srivatsa S. Bhat wrote: > During frequency transitions, the cpufreq core takes the responsibility of > invoking cpufreq_freq_transition_begin() and cpufreq_freq_transition_end() > for those cpufreq drivers that define the ->target_index callback but don't > set the ASYNC_NOTIFICATION flag. > > The powernow-k7 cpufreq driver falls under this category, but this driver was > invoking the _begin() and _end() APIs itself around frequency transitions, > which led to double invocation of the _begin() API. The _begin API makes > contending callers wait until the previous invocation is complete. Hence, > the powernow-k7 driver ended up waiting on itself, leading to system hangs > during boot. > > Fix this by removing the calls to the _begin() and _end() APIs from the > powernow-k7 driver, since they rightly belong to the cpufreq core. > > Signed-off-by: Srivatsa S. Bhat > --- > > drivers/cpufreq/powernow-k7.c | 4 ---- > 1 file changed, 4 deletions(-) Acked-by: Viresh Kumar -- 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/