Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932712Ab3DDCBt (ORCPT ); Wed, 3 Apr 2013 22:01:49 -0400 Received: from mga14.intel.com ([143.182.124.37]:45838 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932691Ab3DDCBs (ORCPT ); Wed, 3 Apr 2013 22:01:48 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.87,404,1363158000"; d="scan'208";a="280534050" From: Alex Shi To: mingo@redhat.com, peterz@infradead.org, tglx@linutronix.de, akpm@linux-foundation.org, arjan@linux.intel.com, bp@alien8.de, pjt@google.com, namhyung@kernel.org, efault@gmx.de, morten.rasmussen@arm.com Cc: vincent.guittot@linaro.org, gregkh@linuxfoundation.org, preeti@linux.vnet.ibm.com, viresh.kumar@linaro.org, linux-kernel@vger.kernel.org, alex.shi@intel.com, len.brown@intel.com, rafael.j.wysocki@intel.com, jkosina@suse.cz, clark.williams@gmail.com, tony.luck@intel.com, keescook@chromium.org, mgorman@suse.de, riel@redhat.com Subject: [patch v7 04/21] sched: add sysfs interface for sched_balance_policy selection Date: Thu, 4 Apr 2013 10:00:45 +0800 Message-Id: <1365040862-8390-5-git-send-email-alex.shi@intel.com> X-Mailer: git-send-email 1.7.12 In-Reply-To: <1365040862-8390-1-git-send-email-alex.shi@intel.com> References: <1365040862-8390-1-git-send-email-alex.shi@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4793 Lines: 139 This patch add the power aware scheduler knob into sysfs: $cat /sys/devices/system/cpu/sched_balance_policy/available_sched_balance_policy performance powersaving $cat /sys/devices/system/cpu/sched_balance_policy/current_sched_balance_policy powersaving This means the using sched balance policy is 'powersaving'. User can change the policy by commend 'echo': echo performance > /sys/devices/system/cpu/sched_balance_policy/current_sched_balance_policy Signed-off-by: Alex Shi --- Documentation/ABI/testing/sysfs-devices-system-cpu | 22 +++++++ kernel/sched/fair.c | 69 ++++++++++++++++++++++ 2 files changed, 91 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 9c978dc..b602882 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -53,6 +53,28 @@ Description: Dynamic addition and removal of CPU's. This is not hotplug the system. Information writtento the file to remove CPU's is architecture specific. +What: /sys/devices/system/cpu/sched_balance_policy/current_sched_balance_policy + /sys/devices/system/cpu/sched_balance_policy/available_sched_balance_policy +Date: Oct 2012 +Contact: Linux kernel mailing list +Description: CFS balance policy show and set interface. + + available_sched_balance_policy: shows there are 2 kinds of + policies: + performance powersaving. + current_sched_balance_policy: shows current scheduler policy. + User can change the policy by writing it. + + Policy decides the CFS scheduler how to balance tasks onto + different CPU unit. + + performance: try to spread tasks onto more CPU sockets, + more CPU cores. performance oriented. + + powersaving: try to pack tasks onto same core or same CPU + until every LCPUs are busy in the core or CPU socket. + powersaving oriented. + What: /sys/devices/system/cpu/cpu#/node Date: October 2009 Contact: Linux memory management mailing list diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 04dd319..2e49c3f 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -6096,6 +6096,75 @@ static unsigned int get_rr_interval_fair(struct rq *rq, struct task_struct *task /* The default scheduler policy is 'performance'. */ int __read_mostly sched_balance_policy = SCHED_POLICY_PERFORMANCE; +#ifdef CONFIG_SYSFS +static ssize_t show_available_sched_balance_policy(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "performance powersaving\n"); +} + +static ssize_t show_current_sched_balance_policy(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (sched_balance_policy == SCHED_POLICY_PERFORMANCE) + return sprintf(buf, "performance\n"); + else if (sched_balance_policy == SCHED_POLICY_POWERSAVING) + return sprintf(buf, "powersaving\n"); + return 0; +} + +static ssize_t set_sched_balance_policy(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + unsigned int ret = -EINVAL; + char str_policy[16]; + + ret = sscanf(buf, "%15s", str_policy); + if (ret != 1) + return -EINVAL; + + if (!strcmp(str_policy, "performance")) + sched_balance_policy = SCHED_POLICY_PERFORMANCE; + else if (!strcmp(str_policy, "powersaving")) + sched_balance_policy = SCHED_POLICY_POWERSAVING; + else + return -EINVAL; + + return count; +} + +/* + * * Sysfs setup bits: + * */ +static DEVICE_ATTR(current_sched_balance_policy, 0644, + show_current_sched_balance_policy, set_sched_balance_policy); + +static DEVICE_ATTR(available_sched_balance_policy, 0444, + show_available_sched_balance_policy, NULL); + +static struct attribute *sched_balance_policy_default_attrs[] = { + &dev_attr_current_sched_balance_policy.attr, + &dev_attr_available_sched_balance_policy.attr, + NULL +}; +static struct attribute_group sched_balance_policy_attr_group = { + .attrs = sched_balance_policy_default_attrs, + .name = "sched_balance_policy", +}; + +int __init create_sysfs_sched_balance_policy_group(struct device *dev) +{ + return sysfs_create_group(&dev->kobj, &sched_balance_policy_attr_group); +} + +static int __init sched_balance_policy_sysfs_init(void) +{ + return create_sysfs_sched_balance_policy_group(cpu_subsys.dev_root); +} + +core_initcall(sched_balance_policy_sysfs_init); +#endif /* CONFIG_SYSFS */ + /* * All the scheduling class methods: */ -- 1.7.12 -- 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/