From patchwork Thu Apr 30 08:39:42 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 11519509 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 5C4E892C for ; Thu, 30 Apr 2020 08:46:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4F53421974 for ; Thu, 30 Apr 2020 08:46:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726893AbgD3IqW (ORCPT ); Thu, 30 Apr 2020 04:46:22 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:3393 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726626AbgD3IqW (ORCPT ); Thu, 30 Apr 2020 04:46:22 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 6AA9EAF8174EEA4EDE8B; Thu, 30 Apr 2020 16:46:20 +0800 (CST) Received: from linux-ibm.site (10.175.102.37) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 30 Apr 2020 16:46:10 +0800 From: Hanjun Guo To: "Rafael J. Wysocki" , Daniel Lezcano , Doug Smythies CC: , Jonathan Corbet , Hanjun Guo Subject: [RFC v2 PATCH 1/6] cpuidle: sysfs: Fix the overlap for showing available governors Date: Thu, 30 Apr 2020 16:39:42 +0800 Message-ID: <1588235987-12300-2-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> References: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org When showing the available governors, it's "%s " in scnprintf(), not "%s", so if the governor name has 15 characters, it will overlap with the later one, fix it by adding one more for the size. While we are at it, fix the minor coding sytle as well. Signed-off-by: Hanjun Guo --- drivers/cpuidle/sysfs.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index d3ef1d7..3485210 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -35,10 +35,10 @@ static ssize_t show_available_governors(struct device *dev, mutex_lock(&cpuidle_lock); list_for_each_entry(tmp, &cpuidle_governors, governor_list) { - if (i >= (ssize_t) ((PAGE_SIZE/sizeof(char)) - + if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) - CPUIDLE_NAME_LEN - 2)) goto out; - i += scnprintf(&buf[i], CPUIDLE_NAME_LEN, "%s ", tmp->name); + i += scnprintf(&buf[i], CPUIDLE_NAME_LEN + 1, "%s ", tmp->name); } out: From patchwork Thu Apr 30 08:39:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 11519521 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 38C7992C for ; Thu, 30 Apr 2020 08:46:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 21D5D20838 for ; Thu, 30 Apr 2020 08:46:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727094AbgD3Iqb (ORCPT ); Thu, 30 Apr 2020 04:46:31 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:3395 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726766AbgD3Iqb (ORCPT ); Thu, 30 Apr 2020 04:46:31 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 557EB5F83E79386DA22A; Thu, 30 Apr 2020 16:46:20 +0800 (CST) Received: from linux-ibm.site (10.175.102.37) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 30 Apr 2020 16:46:11 +0800 From: Hanjun Guo To: "Rafael J. Wysocki" , Daniel Lezcano , Doug Smythies CC: , Jonathan Corbet , Hanjun Guo Subject: [RFC v2 PATCH 2/6] cpuidle: sysfs: Accept governor name with 15 characters Date: Thu, 30 Apr 2020 16:39:43 +0800 Message-ID: <1588235987-12300-3-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> References: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org CPUIDLE_NAME_LEN is 16, so it's possible to accept governor name with 15 characters, but now store_current_governor() rejects governor name with 15 characters as it returns -EINVAL if count equals CPUIDLE_NAME_LEN. Refactor the code to accept such case and simplify the code. Signed-off-by: Hanjun Guo --- drivers/cpuidle/sysfs.c | 23 +++++++---------------- 1 file changed, 7 insertions(+), 16 deletions(-) diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 3485210..af5a65f 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -85,34 +85,25 @@ static ssize_t store_current_governor(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { - char gov_name[CPUIDLE_NAME_LEN]; - int ret = -EINVAL; - size_t len = count; + char gov_name[CPUIDLE_NAME_LEN + 1]; + int ret; struct cpuidle_governor *gov; - if (!len || len >= sizeof(gov_name)) + ret = sscanf(buf, "%" __stringify(CPUIDLE_NAME_LEN) "s", gov_name); + if (ret != 1) return -EINVAL; - memcpy(gov_name, buf, len); - gov_name[len] = '\0'; - if (gov_name[len - 1] == '\n') - gov_name[--len] = '\0'; - mutex_lock(&cpuidle_lock); - + ret = -EINVAL; list_for_each_entry(gov, &cpuidle_governors, governor_list) { - if (strlen(gov->name) == len && !strcmp(gov->name, gov_name)) { + if (!strncmp(gov->name, gov_name, CPUIDLE_NAME_LEN)) { ret = cpuidle_switch_governor(gov); break; } } - mutex_unlock(&cpuidle_lock); - if (ret) - return ret; - else - return count; + return ret ? ret : count; } static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL); From patchwork Thu Apr 30 08:39:44 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 11519519 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 0EAC192C for ; Thu, 30 Apr 2020 08:46:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB8AA20838 for ; Thu, 30 Apr 2020 08:46:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726412AbgD3IqY (ORCPT ); Thu, 30 Apr 2020 04:46:24 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:3398 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726420AbgD3IqX (ORCPT ); Thu, 30 Apr 2020 04:46:23 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 6F52DCA2C81BFA93F45E; Thu, 30 Apr 2020 16:46:20 +0800 (CST) Received: from linux-ibm.site (10.175.102.37) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 30 Apr 2020 16:46:11 +0800 From: Hanjun Guo To: "Rafael J. Wysocki" , Daniel Lezcano , Doug Smythies CC: , Jonathan Corbet , Hanjun Guo Subject: [RFC v2 PATCH 3/6] cpuidle: Make cpuidle governor switchable to be the default behaviour Date: Thu, 30 Apr 2020 16:39:44 +0800 Message-ID: <1588235987-12300-4-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> References: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org For now cpuidle governor can be switched via sysfs only when the boot option "cpuidle_sysfs_switch" is passed, but it's important to switch the governor to adapt to different workloads, especially after TEO and haltpoll governor were introduced. Add available_governors and current_governor into the default attributes, but reserve the current_governor_ro for temporal compatibility. Signed-off-by: Hanjun Guo Acked-by: Daniel Lezcano --- drivers/cpuidle/sysfs.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index af5a65f..2425c6a 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -106,19 +106,20 @@ static ssize_t store_current_governor(struct device *dev, return ret ? ret : count; } +static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL); static DEVICE_ATTR(current_driver, 0444, show_current_driver, NULL); +static DEVICE_ATTR(current_governor, 0644, show_current_governor, + store_current_governor); static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL); static struct attribute *cpuidle_default_attrs[] = { + &dev_attr_available_governors.attr, &dev_attr_current_driver.attr, + &dev_attr_current_governor.attr, &dev_attr_current_governor_ro.attr, NULL }; -static DEVICE_ATTR(available_governors, 0444, show_available_governors, NULL); -static DEVICE_ATTR(current_governor, 0644, show_current_governor, - store_current_governor); - static struct attribute *cpuidle_switch_attrs[] = { &dev_attr_available_governors.attr, &dev_attr_current_driver.attr, From patchwork Thu Apr 30 08:39:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 11519513 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 8DDF192C for ; Thu, 30 Apr 2020 08:46:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E5BA21974 for ; Thu, 30 Apr 2020 08:46:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726474AbgD3IqY (ORCPT ); Thu, 30 Apr 2020 04:46:24 -0400 Received: from szxga05-in.huawei.com ([45.249.212.191]:3349 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726845AbgD3IqX (ORCPT ); Thu, 30 Apr 2020 04:46:23 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 898E14AE9353540B38F3; Thu, 30 Apr 2020 16:46:20 +0800 (CST) Received: from linux-ibm.site (10.175.102.37) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 30 Apr 2020 16:46:11 +0800 From: Hanjun Guo To: "Rafael J. Wysocki" , Daniel Lezcano , Doug Smythies CC: , Jonathan Corbet , Hanjun Guo Subject: [RFC v2 PATCH 4/6] cpuidle: sysfs: Remove sysfs_switch and switch attributes Date: Thu, 30 Apr 2020 16:39:45 +0800 Message-ID: <1588235987-12300-5-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> References: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Since the cpuidle governor can be switched via sysfs in default, remove sysfs_switch and cpuidle_switch_attrs. Signed-off-by: Hanjun Guo Acked-by: Daniel Lezcano --- drivers/cpuidle/sysfs.c | 22 ++-------------------- 1 file changed, 2 insertions(+), 20 deletions(-) diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 2425c6a..c3bbfc7 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -18,14 +18,6 @@ #include "cpuidle.h" -static unsigned int sysfs_switch; -static int __init cpuidle_sysfs_setup(char *unused) -{ - sysfs_switch = 1; - return 1; -} -__setup("cpuidle_sysfs_switch", cpuidle_sysfs_setup); - static ssize_t show_available_governors(struct device *dev, struct device_attribute *attr, char *buf) @@ -112,7 +104,7 @@ static DEVICE_ATTR(current_governor, 0644, show_current_governor, store_current_governor); static DEVICE_ATTR(current_governor_ro, 0444, show_current_governor, NULL); -static struct attribute *cpuidle_default_attrs[] = { +static struct attribute *cpuidle_attrs[] = { &dev_attr_available_governors.attr, &dev_attr_current_driver.attr, &dev_attr_current_governor.attr, @@ -120,15 +112,8 @@ static DEVICE_ATTR(current_governor, 0644, show_current_governor, NULL }; -static struct attribute *cpuidle_switch_attrs[] = { - &dev_attr_available_governors.attr, - &dev_attr_current_driver.attr, - &dev_attr_current_governor.attr, - NULL -}; - static struct attribute_group cpuidle_attr_group = { - .attrs = cpuidle_default_attrs, + .attrs = cpuidle_attrs, .name = "cpuidle", }; @@ -138,9 +123,6 @@ static DEVICE_ATTR(current_governor, 0644, show_current_governor, */ int cpuidle_add_interface(struct device *dev) { - if (sysfs_switch) - cpuidle_attr_group.attrs = cpuidle_switch_attrs; - return sysfs_create_group(&dev->kobj, &cpuidle_attr_group); } From patchwork Thu Apr 30 08:39:46 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 11519515 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 8916892C for ; Thu, 30 Apr 2020 08:46:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 79ECE20787 for ; Thu, 30 Apr 2020 08:46:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726420AbgD3IqZ (ORCPT ); Thu, 30 Apr 2020 04:46:25 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:3397 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726752AbgD3IqY (ORCPT ); Thu, 30 Apr 2020 04:46:24 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 5FA6D4087341CB18A256; Thu, 30 Apr 2020 16:46:20 +0800 (CST) Received: from linux-ibm.site (10.175.102.37) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 30 Apr 2020 16:46:12 +0800 From: Hanjun Guo To: "Rafael J. Wysocki" , Daniel Lezcano , Doug Smythies CC: , Jonathan Corbet , Hanjun Guo Subject: [RFC v2 PATCH 5/6] Documentation: cpuidle: update the document Date: Thu, 30 Apr 2020 16:39:46 +0800 Message-ID: <1588235987-12300-6-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> References: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Update the document after the remove of cpuidle_sysfs_switch. Signed-off-by: Hanjun Guo --- Documentation/ABI/testing/sysfs-devices-system-cpu | 24 ++++++++-------------- Documentation/admin-guide/pm/cpuidle.rst | 20 ++++++++---------- Documentation/driver-api/pm/cpuidle.rst | 5 ++--- 3 files changed, 20 insertions(+), 29 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 2e0e3b4..6b5dafa 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -106,10 +106,10 @@ Description: CPU topology files that describe a logical CPU's relationship See Documentation/admin-guide/cputopology.rst for more information. -What: /sys/devices/system/cpu/cpuidle/current_driver - /sys/devices/system/cpu/cpuidle/current_governer_ro - /sys/devices/system/cpu/cpuidle/available_governors +What: /sys/devices/system/cpu/cpuidle/available_governors + /sys/devices/system/cpu/cpuidle/current_driver /sys/devices/system/cpu/cpuidle/current_governor + /sys/devices/system/cpu/cpuidle/current_governer_ro Date: September 2007 Contact: Linux kernel mailing list Description: Discover cpuidle policy and mechanism @@ -119,24 +119,18 @@ Description: Discover cpuidle policy and mechanism consumption during idle. Idle policy (governor) is differentiated from idle mechanism - (driver) - - current_driver: (RO) displays current idle mechanism - - current_governor_ro: (RO) displays current idle policy - - With the cpuidle_sysfs_switch boot option enabled (meant for - developer testing), the following three attributes are visible - instead: - - current_driver: same as described above + (driver). available_governors: (RO) displays a space separated list of - available governors + available governors. + + current_driver: (RO) displays current idle mechanism. current_governor: (RW) displays current idle policy. Users can switch the governor at runtime by writing to this file. + current_governor_ro: (RO) displays current idle policy. + See Documentation/admin-guide/pm/cpuidle.rst and Documentation/driver-api/pm/cpuidle.rst for more information. diff --git a/Documentation/admin-guide/pm/cpuidle.rst b/Documentation/admin-guide/pm/cpuidle.rst index 5605cc6..a96a423 100644 --- a/Documentation/admin-guide/pm/cpuidle.rst +++ b/Documentation/admin-guide/pm/cpuidle.rst @@ -159,17 +159,15 @@ governor uses that information depends on what algorithm is implemented by it and that is the primary reason for having more than one governor in the ``CPUIdle`` subsystem. -There are three ``CPUIdle`` governors available, ``menu``, `TEO `_ -and ``ladder``. Which of them is used by default depends on the configuration -of the kernel and in particular on whether or not the scheduler tick can be -`stopped by the idle loop `_. It is possible to change the -governor at run time if the ``cpuidle_sysfs_switch`` command line parameter has -been passed to the kernel, but that is not safe in general, so it should not be -done on production systems (that may change in the future, though). The name of -the ``CPUIdle`` governor currently used by the kernel can be read from the -:file:`current_governor_ro` (or :file:`current_governor` if -``cpuidle_sysfs_switch`` is present in the kernel command line) file under -:file:`/sys/devices/system/cpu/cpuidle/` in ``sysfs``. +There are four ``CPUIdle`` governors available, ``menu``, `TEO `_, +``ladder`` and ``haltpoll``. Which of them is used by default depends on the +configuration of the kernel and in particular on whether or not the scheduler +tick can be `stopped by the idle loop `_. Available +governors can be read from the :file:`available_governors`, and the governor +can be changed at runtime. The name of the ``CPUIdle`` governor currently +used by the kernel can be read from the :file:`current_governor_ro` or +:file:`current_governor` file under :file:`/sys/devices/system/cpu/cpuidle/` +in ``sysfs``. Which ``CPUIdle`` driver is used, on the other hand, usually depends on the platform the kernel is running on, but there are platforms with more than one diff --git a/Documentation/driver-api/pm/cpuidle.rst b/Documentation/driver-api/pm/cpuidle.rst index 006cf6d..3588bf0 100644 --- a/Documentation/driver-api/pm/cpuidle.rst +++ b/Documentation/driver-api/pm/cpuidle.rst @@ -68,9 +68,8 @@ only one in the list (that is, the list was empty before) or the value of its governor currently in use, or the name of the new governor was passed to the kernel as the value of the ``cpuidle.governor=`` command line parameter, the new governor will be used from that point on (there can be only one ``CPUIdle`` -governor in use at a time). Also, if ``cpuidle_sysfs_switch`` is passed to the -kernel in the command line, user space can choose the ``CPUIdle`` governor to -use at run time via ``sysfs``. +governor in use at a time). Also, user space can choose the ``CPUIdle`` +governor to use at run time via ``sysfs``. Once registered, ``CPUIdle`` governors cannot be unregistered, so it is not practical to put them into loadable kernel modules. From patchwork Thu Apr 30 08:39:47 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hanjun Guo X-Patchwork-Id: 11519525 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 0DD5392C for ; Thu, 30 Apr 2020 08:46:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 000CF20787 for ; Thu, 30 Apr 2020 08:46:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727794AbgD3Iqt (ORCPT ); Thu, 30 Apr 2020 04:46:49 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:3396 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726766AbgD3Iqs (ORCPT ); Thu, 30 Apr 2020 04:46:48 -0400 Received: from DGGEMS402-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id 5ABEF243B61531968836; Thu, 30 Apr 2020 16:46:20 +0800 (CST) Received: from linux-ibm.site (10.175.102.37) by DGGEMS402-HUB.china.huawei.com (10.3.19.202) with Microsoft SMTP Server id 14.3.487.0; Thu, 30 Apr 2020 16:46:12 +0800 From: Hanjun Guo To: "Rafael J. Wysocki" , Daniel Lezcano , Doug Smythies CC: , Jonathan Corbet , Hanjun Guo Subject: [RFC v2 PATCH 6/6] Documentation: ABI: make current_governer_ro as a candidate for removal Date: Thu, 30 Apr 2020 16:39:47 +0800 Message-ID: <1588235987-12300-7-git-send-email-guohanjun@huawei.com> X-Mailer: git-send-email 1.7.12.4 In-Reply-To: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> References: <1588235987-12300-1-git-send-email-guohanjun@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.102.37] X-CFilter-Loop: Reflected Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Since both current_governor and current_governor_ro co-exist under /sys/devices/te system/cpu/cpuidle/ file, and it's duplicate, make current_governer_ro as a candidate for removal. Signed-off-by: Hanjun Guo Acked-by: Daniel Lezcano --- Documentation/ABI/obsolete/sysfs-cpuidle | 9 +++++++++ 1 file changed, 9 insertions(+) create mode 100644 Documentation/ABI/obsolete/sysfs-cpuidle diff --git a/Documentation/ABI/obsolete/sysfs-cpuidle b/Documentation/ABI/obsolete/sysfs-cpuidle new file mode 100644 index 00000000..f984b9c --- /dev/null +++ b/Documentation/ABI/obsolete/sysfs-cpuidle @@ -0,0 +1,9 @@ +What: /sys/devices/system/cpu/cpuidle/current_governor_ro +Date: April, 2020 +Contact: linux-pm@vger.kernel.org +Description: + current_governor_ro shows current using cpuidle governor, but read only. + with the update that cpuidle governor can be changed at runtime in default, + both current_governor and current_governor_ro co-exist under + /sys/devices/te system/cpu/cpuidle/ file, it's duplicate so make + current_governor_ro obselete.