From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751700AbaD0MjQ (ORCPT ); Sun, 27 Apr 2014 08:39:16 -0400 Received: from v094114.home.net.pl ([79.96.170.134]:58860 "HELO v094114.home.net.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751083AbaD0MjO (ORCPT ); Sun, 27 Apr 2014 08:39:14 -0400 From: "Rafael J. Wysocki" To: Linux PM list Cc: Linux Kernel Mailing List , "'Daniel Lezcano'" , Ingo Molnar , Peter Zijlstra Subject: [PATCH 2/2] cpuidle / menu: Return error code if there are no suitable states Date: Sun, 27 Apr 2014 14:55:30 +0200 Message-ID: <6832089.A5AOPipfbA@vostro.rjw.lan> User-Agent: KMail/4.11.5 (Linux/3.14.0-rc7+; KDE/4.11.5; x86_64; ; ) In-Reply-To: <2471963.urOyfY8mOG@vostro.rjw.lan> References: <2471963.urOyfY8mOG@vostro.rjw.lan> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="utf-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Rafael J. Wysocki If there is a PM QoS latency limit and all of the sufficiently shallow C-states are disabled, the cpuidle menu governor returns 0 which on some systems is CPUIDLE_DRIVER_STATE_START and shouldn't be returned if that C-state has been disabled. Fix the issue by modifying the menu governor to return an error code in such situations. Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/governors/menu.c | 2 +- include/linux/cpuidle.h | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) Index: linux-pm/drivers/cpuidle/governors/menu.c =================================================================== --- linux-pm.orig/drivers/cpuidle/governors/menu.c +++ linux-pm/drivers/cpuidle/governors/menu.c @@ -296,7 +296,7 @@ static int menu_select(struct cpuidle_dr data->needs_update = 0; } - data->last_state_idx = 0; + data->last_state_idx = CPUIDLE_DRIVER_STATE_POLL; /* Special case when user has set very strict latency requirement */ if (unlikely(latency_req == 0)) Index: linux-pm/include/linux/cpuidle.h =================================================================== --- linux-pm.orig/include/linux/cpuidle.h +++ linux-pm/include/linux/cpuidle.h @@ -217,8 +217,10 @@ static inline int cpuidle_register_gover #ifdef CONFIG_ARCH_HAS_CPU_RELAX #define CPUIDLE_DRIVER_STATE_START 1 +#define CPUIDLE_DRIVER_STATE_POLL 0 #else #define CPUIDLE_DRIVER_STATE_START 0 +#define CPUIDLE_DRIVER_STATE_POLL (-ENXIO) #endif #endif /* _LINUX_CPUIDLE_H */