From patchwork Fri Dec 13 09:22:04 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Rafael J. Wysocki" X-Patchwork-Id: 11290327 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 41BC3175D for ; Fri, 13 Dec 2019 09:28:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20E3A2465A for ; Fri, 13 Dec 2019 09:28:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726713AbfLMJ1d (ORCPT ); Fri, 13 Dec 2019 04:27:33 -0500 Received: from cloudserver094114.home.pl ([79.96.170.134]:61210 "EHLO cloudserver094114.home.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725945AbfLMJ1d (ORCPT ); Fri, 13 Dec 2019 04:27:33 -0500 Received: from 79.184.255.82.ipv4.supernova.orange.pl (79.184.255.82) (HELO kreacher.localnet) by serwer1319399.home.pl (79.96.170.134) with SMTP (IdeaSmtpServer 0.83.320) id 3e4136f9a6c3eaa5; Fri, 13 Dec 2019 10:27:30 +0100 From: "Rafael J. Wysocki" To: Linux PM Cc: LKML , Linux ACPI , Len Brown , Srinivas Pandruvada , Len Brown Subject: [PATCH v1 07/10] cpuidle: Allow idle states to be disabled by default Date: Fri, 13 Dec 2019 10:22:04 +0100 Message-ID: <23901825.xGlorUmkL0@kreacher> In-Reply-To: <3950312.2WmFeOdZGY@kreacher> References: <3950312.2WmFeOdZGY@kreacher> MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org From: "Rafael J. Wysocki" In certain situations it may be useful to prevent some idle states from being used by default while allowing user space to enable them later on. For this purpose, introduce a new state flag, CPUIDLE_FLAG_OFF, to mark idle states that should be disabled by default, make the core set CPUIDLE_STATE_DISABLED_BY_USER for those states at the initialization time and add a new state attribute in sysfs, "default_status", to inform user space of the initial status of the given idle state ("disabled" if CPUIDLE_FLAG_OFF is set for it, "enabled" otherwise). Signed-off-by: Rafael J. Wysocki --- Changes from the RFC version: - Call the new sysfs attribute "default_status" (instead of "initial_status"). --- Documentation/ABI/testing/sysfs-devices-system-cpu | 6 ++++++ Documentation/admin-guide/pm/cpuidle.rst | 3 +++ drivers/cpuidle/cpuidle.c | 6 +++++- drivers/cpuidle/sysfs.c | 10 ++++++++++ include/linux/cpuidle.h | 1 + 5 files changed, 25 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index fc20cde63d1e..2e0e3b45d02a 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -196,6 +196,12 @@ Description: does not reflect it. Likewise, if one enables a deep state but a lighter state still is disabled, then this has no effect. +What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/default_status +Date: December 2019 +KernelVersion: v5.6 +Contact: Linux power management list +Description: + (RO) The default status of this state, "enabled" or "disabled". What: /sys/devices/system/cpu/cpuX/cpuidle/stateN/residency Date: March 2014 diff --git a/Documentation/admin-guide/pm/cpuidle.rst b/Documentation/admin-guide/pm/cpuidle.rst index e70b365dbc60..311cd7cc2b75 100644 --- a/Documentation/admin-guide/pm/cpuidle.rst +++ b/Documentation/admin-guide/pm/cpuidle.rst @@ -506,6 +506,9 @@ object corresponding to it, as follows: ``disable`` Whether or not this idle state is disabled. +``default_status`` + The default status of this state, "enabled" or "disabled". + ``latency`` Exit latency of the idle state in microseconds. diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 0005be5ea2b4..24eaa4c8138b 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -571,10 +571,14 @@ static int __cpuidle_register_device(struct cpuidle_device *dev) if (!try_module_get(drv->owner)) return -EINVAL; - for (i = 0; i < drv->state_count; i++) + for (i = 0; i < drv->state_count; i++) { if (drv->states[i].flags & CPUIDLE_FLAG_UNUSABLE) dev->states_usage[i].disable |= CPUIDLE_STATE_DISABLED_BY_DRIVER; + if (drv->states[i].flags & CPUIDLE_FLAG_OFF) + dev->states_usage[i].disable |= CPUIDLE_STATE_DISABLED_BY_USER; + } + per_cpu(cpuidle_devices, dev->cpu) = dev; list_add(&dev->device_list, &cpuidle_detected_devices); diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 38ef770be90d..254d1560dc19 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -327,6 +327,14 @@ static ssize_t store_state_disable(struct cpuidle_state *state, return size; } +static ssize_t show_state_default_status(struct cpuidle_state *state, + struct cpuidle_state_usage *state_usage, + char *buf) +{ + return sprintf(buf, "%s\n", + state->flags & CPUIDLE_FLAG_OFF ? "disabled" : "enabled"); +} + define_one_state_ro(name, show_state_name); define_one_state_ro(desc, show_state_desc); define_one_state_ro(latency, show_state_exit_latency); @@ -337,6 +345,7 @@ define_one_state_ro(time, show_state_time); define_one_state_rw(disable, show_state_disable, store_state_disable); define_one_state_ro(above, show_state_above); define_one_state_ro(below, show_state_below); +define_one_state_ro(default_status, show_state_default_status); static struct attribute *cpuidle_state_default_attrs[] = { &attr_name.attr, @@ -349,6 +358,7 @@ static struct attribute *cpuidle_state_default_attrs[] = { &attr_disable.attr, &attr_above.attr, &attr_below.attr, + &attr_default_status.attr, NULL }; diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h index 1dabe36bd011..ebfb52b3ffbf 100644 --- a/include/linux/cpuidle.h +++ b/include/linux/cpuidle.h @@ -77,6 +77,7 @@ struct cpuidle_state { #define CPUIDLE_FLAG_COUPLED BIT(1) /* state applies to multiple cpus */ #define CPUIDLE_FLAG_TIMER_STOP BIT(2) /* timer is stopped on this state */ #define CPUIDLE_FLAG_UNUSABLE BIT(3) /* avoid using this state */ +#define CPUIDLE_FLAG_OFF BIT(4) /* disable this state by default */ struct cpuidle_device_kobj; struct cpuidle_state_kobj;