From 4a823c0be80fa996234ebb41c80d40458b1bec1e Mon Sep 17 00:00:00 2001
From: Jia-Ju Bai <baijiaju1990@gmail.com>
Date: Fri, 26 Jan 2018 16:48:49 +0800
Subject: [PATCH 1/3] opp: cpu: Replace GFP_ATOMIC with GFP_KERNEL in
 dev_pm_opp_init_cpufreq_table

After checking all possible call chains to
dev_pm_opp_init_cpufreq_table() here,
my tool finds that this function is never called in atomic context,
namely never in an interrupt handler or holding a spinlock.
And dev_pm_opp_init_cpufreq_table() calls dev_pm_opp_get_opp_count(),
which calls mutex_lock that can sleep.
It indicates that atmtcp_v_send() can call functions which may sleep.
Thus GFP_ATOMIC is not necessary, and it can be replaced with GFP_KERNEL.

This is found by a static analysis tool named DCNS written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/opp/cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/opp/cpu.c b/drivers/opp/cpu.c
index 2d87bc1adf38b..0c09107094350 100644
--- a/drivers/opp/cpu.c
+++ b/drivers/opp/cpu.c
@@ -55,7 +55,7 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
 	if (max_opps <= 0)
 		return max_opps ? max_opps : -ENODATA;
 
-	freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC);
+	freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL);
 	if (!freq_table)
 		return -ENOMEM;
 

From b6d8ef86cb7b8b6920b6815ebf1352757d3adb87 Mon Sep 17 00:00:00 2001
From: Aishwarya Pant <aishpant@gmail.com>
Date: Wed, 7 Feb 2018 19:04:36 +0530
Subject: [PATCH 2/3] Documentation/ABI: update cpuidle sysfs documentation

Update cpuidle documentation using git logs and existing documentation
in Documentation/cpuidle/sysfs.txt. This might be useful for scripting
and tracking changes in the ABI.

Signed-off-by: Aishwarya Pant <aishpant@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 .../ABI/testing/sysfs-devices-system-cpu      | 77 ++++++++++++++++++-
 1 file changed, 75 insertions(+), 2 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu
index bfd29bc8d37af..4ed63b6cfb155 100644
--- a/Documentation/ABI/testing/sysfs-devices-system-cpu
+++ b/Documentation/ABI/testing/sysfs-devices-system-cpu
@@ -108,6 +108,8 @@ Description:	CPU topology files that describe a logical CPU's relationship
 
 What:		/sys/devices/system/cpu/cpuidle/current_driver
 		/sys/devices/system/cpu/cpuidle/current_governer_ro
+		/sys/devices/system/cpu/cpuidle/available_governors
+		/sys/devices/system/cpu/cpuidle/current_governor
 Date:		September 2007
 Contact:	Linux kernel mailing list <linux-kernel@vger.kernel.org>
 Description:	Discover cpuidle policy and mechanism
@@ -119,13 +121,84 @@ Description:	Discover cpuidle policy and mechanism
 		Idle policy (governor) is differentiated from idle mechanism
 		(driver)
 
-		current_driver: displays current idle mechanism
+		current_driver: (RO) displays current idle mechanism
 
-		current_governor_ro: displays current idle policy
+		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
+
+		available_governors: (RO) displays a space separated list of
+		available governors
+
+		current_governor: (RW) displays current idle policy. Users can
+		switch the governor at runtime by writing to this file.
 
 		See files in Documentation/cpuidle/ for more information.
 
 
+What:		/sys/devices/system/cpu/cpuX/cpuidle/stateN/name
+		/sys/devices/system/cpu/cpuX/cpuidle/stateN/latency
+		/sys/devices/system/cpu/cpuX/cpuidle/stateN/power
+		/sys/devices/system/cpu/cpuX/cpuidle/stateN/time
+		/sys/devices/system/cpu/cpuX/cpuidle/stateN/usage
+Date:		September 2007
+KernelVersion:	v2.6.24
+Contact:	Linux power management list <linux-pm@vger.kernel.org>
+Description:
+		The directory /sys/devices/system/cpu/cpuX/cpuidle contains per
+		logical CPU specific cpuidle information for each online cpu X.
+		The processor idle states which are available for use have the
+		following attributes:
+
+		name: (RO) Name of the idle state (string).
+
+		latency: (RO) The latency to exit out of this idle state (in
+		microseconds).
+
+		power: (RO) The power consumed while in this idle state (in
+		milliwatts).
+
+		time: (RO) The total time spent in this idle state (in microseconds).
+
+		usage: (RO) Number of times this state was entered (a count).
+
+
+What:		/sys/devices/system/cpu/cpuX/cpuidle/stateN/desc
+Date:		February 2008
+KernelVersion:	v2.6.25
+Contact:	Linux power management list <linux-pm@vger.kernel.org>
+Description:
+		(RO) A small description about the idle state (string).
+
+
+What:		/sys/devices/system/cpu/cpuX/cpuidle/stateN/disable
+Date:		March 2012
+KernelVersion:	v3.10
+Contact:	Linux power management list <linux-pm@vger.kernel.org>
+Description:
+		(RW) Option to disable this idle state (bool). The behavior and
+		the effect of the disable variable depends on the implementation
+		of a particular governor. In the ladder governor, for example,
+		it is not coherent, i.e. if one is disabling a light state, then
+		all deeper states are disabled as well, but the disable variable
+		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/residency
+Date:		March 2014
+KernelVersion:	v3.15
+Contact:	Linux power management list <linux-pm@vger.kernel.org>
+Description:
+		(RO) Display the target residency i.e. the minimum amount of
+		time (in microseconds) this cpu should spend in this idle state
+		to make the transition worth the effort.
+
+
 What:		/sys/devices/system/cpu/cpu#/cpufreq/*
 Date:		pre-git history
 Contact:	linux-pm@vger.kernel.org

From d7212cfb05ba802bea4dd6c90d61cfe6366ea224 Mon Sep 17 00:00:00 2001
From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Date: Mon, 12 Feb 2018 11:34:22 +0100
Subject: [PATCH 3/3] PM: cpuidle: Fix cpuidle_poll_state_init() prototype

Commit f85942207516 (x86: PM: Make APM idle driver initialize polling
state) made apm_init() call cpuidle_poll_state_init(), but that only
is defined for CONFIG_CPU_IDLE set, so make the empty stub of it
available for CONFIG_CPU_IDLE unset too to fix the resulting build
issue.

Fixes: f85942207516 (x86: PM: Make APM idle driver initialize polling state)
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 include/linux/cpuidle.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/cpuidle.h b/include/linux/cpuidle.h
index 8f7788d23b573..a6989e02d0a06 100644
--- a/include/linux/cpuidle.h
+++ b/include/linux/cpuidle.h
@@ -225,7 +225,7 @@ static inline void cpuidle_coupled_parallel_barrier(struct cpuidle_device *dev,
 }
 #endif
 
-#ifdef CONFIG_ARCH_HAS_CPU_RELAX
+#if defined(CONFIG_CPU_IDLE) && defined(CONFIG_ARCH_HAS_CPU_RELAX)
 void cpuidle_poll_state_init(struct cpuidle_driver *drv);
 #else
 static inline void cpuidle_poll_state_init(struct cpuidle_driver *drv) {}