From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752172AbaK1SaA (ORCPT ); Fri, 28 Nov 2014 13:30:00 -0500 Received: from mail-wi0-f180.google.com ([209.85.212.180]:39856 "EHLO mail-wi0-f180.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751174AbaK1SYZ (ORCPT ); Fri, 28 Nov 2014 13:24:25 -0500 From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Tony Luck , Peter Zijlstra , Heiko Carstens , Benjamin Herrenschmidt , Thomas Gleixner , Oleg Nesterov , Paul Mackerras , Wu Fengguang , Ingo Molnar , Rik van Riel , Martin Schwidefsky Subject: [RFC PATCH 08/30] apm32: Fix cputime == jiffies assumption Date: Fri, 28 Nov 2014 19:23:38 +0100 Message-Id: <1417199040-21044-9-git-send-email-fweisbec@gmail.com> X-Mailer: git-send-email 2.1.3 In-Reply-To: <1417199040-21044-1-git-send-email-fweisbec@gmail.com> References: <1417199040-21044-1-git-send-email-fweisbec@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org That code wrongly assumes that cputime_t wraps jiffies_t. Lets use the correct accessors/mutators. Cc: Benjamin Herrenschmidt Cc: Heiko Carstens Cc: Ingo Molnar Cc: Martin Schwidefsky Cc: Oleg Nesterov Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Rik van Riel Cc: Thomas Gleixner Cc: Tony Luck Cc: Wu Fengguang Signed-off-by: Frederic Weisbecker --- arch/x86/kernel/apm_32.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/apm_32.c b/arch/x86/kernel/apm_32.c index 5848744..b3949c3 100644 --- a/arch/x86/kernel/apm_32.c +++ b/arch/x86/kernel/apm_32.c @@ -920,7 +920,7 @@ recalc: } else if (jiffies_since_last_check > idle_period) { unsigned int idle_percentage; - idle_percentage = stime - last_stime; + idle_percentage = cputime_to_jiffies(stime - last_stime); idle_percentage *= 100; idle_percentage /= jiffies_since_last_check; use_apm_idle = (idle_percentage > idle_threshold); -- 2.1.3