From: Jacob Pan <jacob.jun.pan@linux.intel.com>
To: LKML <linux-kernel@vger.kernel.org>,
Linux PM <linux-pm@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>,
Rafael Wysocki <rafael.j.wysocki@intel.com>,
"Chen, Yu C" <yu.c.chen@intel.com>,
Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
Petr Mladek <pmladek@suse.com>,
Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
Arjan van de Ven <arjan@linux.intel.com>,
Jacob Pan <jacob.jun.pan@linux.intel.com>
Subject: [PATCH 2/3] cpuidle: allow setting deepest idle
Date: Wed, 9 Nov 2016 11:05:11 -0800 [thread overview]
Message-ID: <1478718312-12847-3-git-send-email-jacob.jun.pan@linux.intel.com> (raw)
In-Reply-To: <1478718312-12847-1-git-send-email-jacob.jun.pan@linux.intel.com>
When idle injection is used to cap power, we need to override
governor's choice of idle states. This patch allows caller to select
the deepest idle state on a CPU therefore achieve the maximum
potential power saving.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
---
drivers/cpuidle/cpuidle.c | 12 ++++++++++++
include/linux/cpuidle.h | 4 +++-
kernel/sched/idle.c | 3 +++
3 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index c73207a..9ad45b3 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -97,6 +97,18 @@ static int find_deepest_state(struct cpuidle_driver *drv,
return ret;
}
+/* Set the current cpu to use the deepest idle state, override governors */
+void cpuidle_use_deepest_state(bool enable)
+{
+ struct cpuidle_device *dev;
+
+ preempt_disable();
+ dev = cpuidle_get_device();
+ dev->use_deepest_state = enable;
+ preempt_enable();
+}
+EXPORT_SYMBOL_GPL(cpuidle_use_deepest_state);
+
#ifdef CONFIG_SUSPEND
/**
* cpuidle_find_deepest_state - Find the deepest available idle state.
diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index bb31373..7f93c63 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -74,6 +74,7 @@ struct cpuidle_state {
struct cpuidle_device {
unsigned int registered:1;
unsigned int enabled:1;
+ unsigned int use_deepest_state:1;
unsigned int cpu;
int last_residency;
@@ -192,11 +193,12 @@ static inline struct cpuidle_driver *cpuidle_get_cpu_driver(
static inline struct cpuidle_device *cpuidle_get_device(void) {return NULL; }
#endif
-#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_SUSPEND)
+#if defined(CONFIG_CPU_IDLE)
extern int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
struct cpuidle_device *dev);
extern int cpuidle_enter_freeze(struct cpuidle_driver *drv,
struct cpuidle_device *dev);
+extern void cpuidle_use_deepest_state(bool enable);
#else
static inline int cpuidle_find_deepest_state(struct cpuidle_driver *drv,
struct cpuidle_device *dev)
diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index ffd9a83..fc65147 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -173,6 +173,9 @@ static void cpuidle_idle_call(void)
next_state = cpuidle_find_deepest_state(drv, dev);
call_cpuidle(drv, dev, next_state);
+ } else if (dev->use_deepest_state) {
+ next_state = cpuidle_find_deepest_state(drv, dev);
+ call_cpuidle(drv, dev, next_state);
} else {
/*
* Ask the cpuidle framework to choose a convenient idle state.
--
1.9.1
next prev parent reply other threads:[~2016-11-09 19:07 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-09 19:05 [PATCH 0/3] Stop sched tick in idle injection task Jacob Pan
2016-11-09 19:05 ` [PATCH 1/3] idle: add support for tasks that inject idle Jacob Pan
2016-11-14 14:57 ` Peter Zijlstra
2016-11-14 15:01 ` Peter Zijlstra
2016-11-14 15:01 ` Peter Zijlstra
2016-11-14 16:20 ` Jacob Pan
2016-11-14 16:22 ` Peter Zijlstra
2016-11-14 16:29 ` Jacob Pan
2016-11-09 19:05 ` Jacob Pan [this message]
2016-11-14 14:58 ` [PATCH 2/3] cpuidle: allow setting deepest idle Peter Zijlstra
2016-11-09 19:05 ` [PATCH 3/3] thermal/powerclamp: use PF_IDLE in injection kthread Jacob Pan
2016-11-14 15:11 ` Peter Zijlstra
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