From e788892ba3cc71d385b75895f7a375fbc659ce86 Mon Sep 17 00:00:00 2001
From: Rafael J. Wysocki
Date: Thu, 2 Jun 2016 23:24:15 +0200
Subject: cpufreq: governor: Get rid of governor events

The design of the cpufreq governor API is not very straightforward,
as struct cpufreq_governor provides only one callback to be invoked
from different code paths for different purposes.  The purpose it is
invoked for is determined by its second "event" argument, causing it
to act as a "callback multiplexer" of sorts.

Unfortunately, that leads to extra complexity in governors, some of
which implement the ->governor() callback as a switch statement
that simply checks the event argument and invokes a separate function
to handle that specific event.

That extra complexity can be eliminated by replacing the all-purpose
->governor() callback with a family of callbacks to carry out specific
governor operations: initialization and exit, start and stop and policy
limits updates.  That also turns out to reduce the code size too, so
do it.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 include/linux/cpufreq.h | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 4e81e08db752..5bcda3e6aa9e 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -455,18 +455,14 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
 #define MIN_LATENCY_MULTIPLIER		(20)
 #define TRANSITION_LATENCY_LIMIT	(10 * 1000 * 1000)
 
-/* Governor Events */
-#define CPUFREQ_GOV_START	1
-#define CPUFREQ_GOV_STOP	2
-#define CPUFREQ_GOV_LIMITS	3
-#define CPUFREQ_GOV_POLICY_INIT	4
-#define CPUFREQ_GOV_POLICY_EXIT	5
-
 struct cpufreq_governor {
 	char	name[CPUFREQ_NAME_LEN];
 	int	initialized;
-	int	(*governor)	(struct cpufreq_policy *policy,
-				 unsigned int event);
+	int	(*init)(struct cpufreq_policy *policy);
+	void	(*exit)(struct cpufreq_policy *policy);
+	int	(*start)(struct cpufreq_policy *policy);
+	void	(*stop)(struct cpufreq_policy *policy);
+	void	(*limits)(struct cpufreq_policy *policy);
 	ssize_t	(*show_setspeed)	(struct cpufreq_policy *policy,
 					 char *buf);
 	int	(*store_setspeed)	(struct cpufreq_policy *policy,
-- 
cgit v1.2.3-55-g7522


From bf2be2de8493dd5f86d6e0f0d4eecb5810ad035b Mon Sep 17 00:00:00 2001
From: Viresh Kumar
Date: Wed, 18 May 2016 17:55:31 +0530
Subject: cpufreq: governor: Create cpufreq_policy_apply_limits()

Create a new helper to avoid code duplication across governors.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/cpufreq/cpufreq_governor.c | 7 +------
 include/linux/cpufreq.h            | 8 ++++++++
 kernel/sched/cpufreq_schedutil.c   | 9 +--------
 3 files changed, 10 insertions(+), 14 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 18eab7f4ba4c..4b88b5bec4ef 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -553,12 +553,7 @@ void cpufreq_dbs_governor_limits(struct cpufreq_policy *policy)
 	struct policy_dbs_info *policy_dbs = policy->governor_data;
 
 	mutex_lock(&policy_dbs->timer_mutex);
-
-	if (policy->max < policy->cur)
-		__cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
-	else if (policy->min > policy->cur)
-		__cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
-
+	cpufreq_policy_apply_limits(policy);
 	gov_update_sample_delay(policy_dbs, 0);
 
 	mutex_unlock(&policy_dbs->timer_mutex);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 5bcda3e6aa9e..3be54a0b4373 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -489,6 +489,14 @@ void cpufreq_unregister_governor(struct cpufreq_governor *governor);
 struct cpufreq_governor *cpufreq_default_governor(void);
 struct cpufreq_governor *cpufreq_fallback_governor(void);
 
+static inline void cpufreq_policy_apply_limits(struct cpufreq_policy *policy)
+{
+	if (policy->max < policy->cur)
+		__cpufreq_driver_target(policy, policy->max, CPUFREQ_RELATION_H);
+	else if (policy->min > policy->cur)
+		__cpufreq_driver_target(policy, policy->min, CPUFREQ_RELATION_L);
+}
+
 /* Governor attribute set */
 struct gov_attr_set {
 	struct kobject kobj;
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index fdcee3cf38fc..758efd7f3abe 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -463,14 +463,7 @@ static void sugov_limits(struct cpufreq_policy *policy)
 
 	if (!policy->fast_switch_enabled) {
 		mutex_lock(&sg_policy->work_lock);
-
-		if (policy->max < policy->cur)
-			__cpufreq_driver_target(policy, policy->max,
-						CPUFREQ_RELATION_H);
-		else if (policy->min > policy->cur)
-			__cpufreq_driver_target(policy, policy->min,
-						CPUFREQ_RELATION_L);
-
+		cpufreq_policy_apply_limits(policy);
 		mutex_unlock(&sg_policy->work_lock);
 	}
 
-- 
cgit v1.2.3-55-g7522


From 9a15fb2c797a15524e63eacb10bd6cd68a99e830 Mon Sep 17 00:00:00 2001
From: Rafael J. Wysocki
Date: Wed, 18 May 2016 22:59:49 +0200
Subject: cpufreq: Drop the 'initialized' field from struct cpufreq_governor

The 'initialized' field in struct cpufreq_governor is only used by
the conservative governor (as a usage counter) and the way that
happens is far from straightforward and arguably incorrect.

Namely, the value of 'initialized' is checked by
cpufreq_dbs_governor_init() and cpufreq_dbs_governor_exit() and
the results of those checks are passed (as the second argument) to
the ->init() and ->exit() callbacks in struct dbs_governor.  Those
callbacks are only implemented by the ondemand and conservative
governors and ondemand doesn't use their second argument at all.
In turn, the conservative governor uses it to decide whether or not
to either register or unregister a transition notifier.

That whole mechanism is not only unnecessarily convoluted, but also
racy, because the 'initialized' field of struct cpufreq_governor is
updated in cpufreq_init_governor() and cpufreq_exit_governor() under
policy->rwsem which doesn't help if one of these functions is run
twice in parallel for different policies (which isn't impossible in
principle), for example.

Instead of it, add a proper usage counter to the conservative
governor and update it from cs_init() and cs_exit() which is
guaranteed to be non-racy, as those functions are only called
under gov_dbs_data_mutex which is global.

With that in place, drop the 'initialized' field from struct
cpufreq_governor as it is not used any more.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/cpufreq/cpufreq.c              |  3 ---
 drivers/cpufreq/cpufreq_conservative.c | 44 ++++++++++++++++++++++------------
 drivers/cpufreq/cpufreq_governor.c     |  6 ++---
 drivers/cpufreq/cpufreq_governor.h     |  4 ++--
 drivers/cpufreq/cpufreq_ondemand.c     |  4 ++--
 include/linux/cpufreq.h                |  1 -
 6 files changed, 36 insertions(+), 26 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index d98ff688b2f1..bdf1f280ae39 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2031,7 +2031,6 @@ static int cpufreq_init_governor(struct cpufreq_policy *policy)
 		}
 	}
 
-	policy->governor->initialized++;
 	return 0;
 }
 
@@ -2045,7 +2044,6 @@ static void cpufreq_exit_governor(struct cpufreq_policy *policy)
 	if (policy->governor->exit)
 		policy->governor->exit(policy);
 
-	policy->governor->initialized--;
 	module_put(policy->governor->owner);
 }
 
@@ -2110,7 +2108,6 @@ int cpufreq_register_governor(struct cpufreq_governor *governor)
 
 	mutex_lock(&cpufreq_governor_mutex);
 
-	governor->initialized = 0;
 	err = -EBUSY;
 	if (!find_governor(governor->name)) {
 		err = 0;
diff --git a/drivers/cpufreq/cpufreq_conservative.c b/drivers/cpufreq/cpufreq_conservative.c
index 78faa9fbc384..f967ec6c5720 100644
--- a/drivers/cpufreq/cpufreq_conservative.c
+++ b/drivers/cpufreq/cpufreq_conservative.c
@@ -127,7 +127,6 @@ static struct notifier_block cs_cpufreq_notifier_block = {
 };
 
 /************************** sysfs interface ************************/
-static struct dbs_governor cs_dbs_gov;
 
 static ssize_t store_sampling_down_factor(struct gov_attr_set *attr_set,
 					  const char *buf, size_t count)
@@ -255,6 +254,13 @@ static struct attribute *cs_attributes[] = {
 
 /************************** sysfs end ************************/
 
+struct cs_governor {
+	struct dbs_governor dbs_gov;
+	unsigned int usage_count;
+};
+
+static struct cs_governor cs_gov;
+
 static struct policy_dbs_info *cs_alloc(void)
 {
 	struct cs_policy_dbs_info *dbs_info;
@@ -268,7 +274,7 @@ static void cs_free(struct policy_dbs_info *policy_dbs)
 	kfree(to_dbs_info(policy_dbs));
 }
 
-static int cs_init(struct dbs_data *dbs_data, bool notify)
+static int cs_init(struct dbs_data *dbs_data)
 {
 	struct cs_dbs_tuners *tuners;
 
@@ -286,16 +292,22 @@ static int cs_init(struct dbs_data *dbs_data, bool notify)
 	dbs_data->min_sampling_rate = MIN_SAMPLING_RATE_RATIO *
 		jiffies_to_usecs(10);
 
-	if (notify)
+	/*
+	 * This function and cs_exit() are only called under gov_dbs_data_mutex
+	 * which is global, so the cs_gov.usage_count accesses are guaranteed
+	 * to be serialized.
+	 */
+	if (!cs_gov.usage_count++)
 		cpufreq_register_notifier(&cs_cpufreq_notifier_block,
 					  CPUFREQ_TRANSITION_NOTIFIER);
 
 	return 0;
 }
 
-static void cs_exit(struct dbs_data *dbs_data, bool notify)
+static void cs_exit(struct dbs_data *dbs_data)
 {
-	if (notify)
+	/* Protected by gov_dbs_data_mutex - see the comment in cs_init(). */
+	if (!--cs_gov.usage_count)
 		cpufreq_unregister_notifier(&cs_cpufreq_notifier_block,
 					    CPUFREQ_TRANSITION_NOTIFIER);
 
@@ -310,18 +322,20 @@ static void cs_start(struct cpufreq_policy *policy)
 	dbs_info->requested_freq = policy->cur;
 }
 
-static struct dbs_governor cs_dbs_gov = {
-	.gov = CPUFREQ_DBS_GOVERNOR_INITIALIZER("conservative"),
-	.kobj_type = { .default_attrs = cs_attributes },
-	.gov_dbs_timer = cs_dbs_timer,
-	.alloc = cs_alloc,
-	.free = cs_free,
-	.init = cs_init,
-	.exit = cs_exit,
-	.start = cs_start,
+static struct cs_governor cs_gov = {
+	.dbs_gov = {
+		.gov = CPUFREQ_DBS_GOVERNOR_INITIALIZER("conservative"),
+		.kobj_type = { .default_attrs = cs_attributes },
+		.gov_dbs_timer = cs_dbs_timer,
+		.alloc = cs_alloc,
+		.free = cs_free,
+		.init = cs_init,
+		.exit = cs_exit,
+		.start = cs_start,
+	},
 };
 
-#define CPU_FREQ_GOV_CONSERVATIVE	(&cs_dbs_gov.gov)
+#define CPU_FREQ_GOV_CONSERVATIVE	(&cs_gov.dbs_gov.gov)
 
 static int dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
 				void *data)
diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 4b88b5bec4ef..31369e247192 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -429,7 +429,7 @@ int cpufreq_dbs_governor_init(struct cpufreq_policy *policy)
 
 	gov_attr_set_init(&dbs_data->attr_set, &policy_dbs->list);
 
-	ret = gov->init(dbs_data, !policy->governor->initialized);
+	ret = gov->init(dbs_data);
 	if (ret)
 		goto free_policy_dbs_info;
 
@@ -464,7 +464,7 @@ int cpufreq_dbs_governor_init(struct cpufreq_policy *policy)
 
 	if (!have_governor_per_policy())
 		gov->gdbs_data = NULL;
-	gov->exit(dbs_data, !policy->governor->initialized);
+	gov->exit(dbs_data);
 	kfree(dbs_data);
 
 free_policy_dbs_info:
@@ -494,7 +494,7 @@ void cpufreq_dbs_governor_exit(struct cpufreq_policy *policy)
 		if (!have_governor_per_policy())
 			gov->gdbs_data = NULL;
 
-		gov->exit(dbs_data, policy->governor->initialized == 1);
+		gov->exit(dbs_data);
 		kfree(dbs_data);
 	}
 
diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
index 36f0d19dd869..ef1037e9c92b 100644
--- a/drivers/cpufreq/cpufreq_governor.h
+++ b/drivers/cpufreq/cpufreq_governor.h
@@ -138,8 +138,8 @@ struct dbs_governor {
 	unsigned int (*gov_dbs_timer)(struct cpufreq_policy *policy);
 	struct policy_dbs_info *(*alloc)(void);
 	void (*free)(struct policy_dbs_info *policy_dbs);
-	int (*init)(struct dbs_data *dbs_data, bool notify);
-	void (*exit)(struct dbs_data *dbs_data, bool notify);
+	int (*init)(struct dbs_data *dbs_data);
+	void (*exit)(struct dbs_data *dbs_data);
 	void (*start)(struct cpufreq_policy *policy);
 };
 
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index 4441a11139f1..c84fc2240d49 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -361,7 +361,7 @@ static void od_free(struct policy_dbs_info *policy_dbs)
 	kfree(to_dbs_info(policy_dbs));
 }
 
-static int od_init(struct dbs_data *dbs_data, bool notify)
+static int od_init(struct dbs_data *dbs_data)
 {
 	struct od_dbs_tuners *tuners;
 	u64 idle_time;
@@ -400,7 +400,7 @@ static int od_init(struct dbs_data *dbs_data, bool notify)
 	return 0;
 }
 
-static void od_exit(struct dbs_data *dbs_data, bool notify)
+static void od_exit(struct dbs_data *dbs_data)
 {
 	kfree(dbs_data->tuners);
 }
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 3be54a0b4373..fbd696edf5bd 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -457,7 +457,6 @@ static inline unsigned long cpufreq_scale(unsigned long old, u_int div,
 
 struct cpufreq_governor {
 	char	name[CPUFREQ_NAME_LEN];
-	int	initialized;
 	int	(*init)(struct cpufreq_policy *policy);
 	void	(*exit)(struct cpufreq_policy *policy);
 	int	(*start)(struct cpufreq_policy *policy);
-- 
cgit v1.2.3-55-g7522


From 1aefc75b2449eb68a6fc3ca932e2a4ee353b748d Mon Sep 17 00:00:00 2001
From: Rafael J. Wysocki
Date: Tue, 31 May 2016 22:14:44 +0200
Subject: cpufreq: stats: Make the stats code non-modular

The modularity of cpufreq_stats is quite problematic.

First off, the usage of policy notifiers for the initialization
and cleanup in the cpufreq_stats module is inherently racy with
respect to CPU offline/online and the initialization and cleanup
of the cpufreq driver.

Second, fast frequency switching (used by the schedutil governor)
cannot be enabled if any transition notifiers are registered, so
if the cpufreq_stats module (that registers a transition notifier
for updating transition statistics) is loaded, the schedutil governor
cannot use fast frequency switching.

On the other hand, allowing cpufreq_stats to be built as a module
doesn't really add much value.  Arguably, there's not much reason
for that code to be modular at all.

For the above reasons, make the cpufreq stats code non-modular,
modify the core to invoke functions provided by that code directly
and drop the notifiers from it.

Make the stats sysfs attributes appear empty if fast frequency
switching is enabled as the statistics will not be updated in that
case anyway (and returning -EBUSY from those attributes breaks
powertop).

While at it, clean up Kconfig help for the CPU_FREQ_STAT and
CPU_FREQ_STAT_DETAILS options.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 drivers/cpufreq/Kconfig         |  13 ++--
 drivers/cpufreq/cpufreq.c       |   4 ++
 drivers/cpufreq/cpufreq_stats.c | 154 ++++++----------------------------------
 include/linux/cpufreq.h         |  12 ++++
 4 files changed, 41 insertions(+), 142 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig
index b7445b6ae5a4..c822d72629d5 100644
--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig
@@ -31,23 +31,18 @@ config CPU_FREQ_BOOST_SW
 	depends on THERMAL
 
 config CPU_FREQ_STAT
-	tristate "CPU frequency translation statistics"
+	bool "CPU frequency transition statistics"
 	default y
 	help
-	  This driver exports CPU frequency statistics information through sysfs
-	  file system.
-
-	  To compile this driver as a module, choose M here: the
-	  module will be called cpufreq_stats.
+	  Export CPU frequency statistics information through sysfs.
 
 	  If in doubt, say N.
 
 config CPU_FREQ_STAT_DETAILS
-	bool "CPU frequency translation statistics details"
+	bool "CPU frequency transition statistics details"
 	depends on CPU_FREQ_STAT
 	help
-	  This will show detail CPU frequency translation table in sysfs file
-	  system.
+	  Show detailed CPU frequency transition table in sysfs.
 
 	  If in doubt, say N.
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 198416bc22de..c6a14ba239a2 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -347,6 +347,7 @@ static void __cpufreq_notify_transition(struct cpufreq_policy *policy,
 		pr_debug("FREQ: %lu - CPU: %lu\n",
 			 (unsigned long)freqs->new, (unsigned long)freqs->cpu);
 		trace_cpu_frequency(freqs->new, freqs->cpu);
+		cpufreq_stats_record_transition(policy, freqs->new);
 		srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
 				CPUFREQ_POSTCHANGE, freqs);
 		if (likely(policy) && likely(policy->cpu == freqs->cpu))
@@ -1108,6 +1109,7 @@ static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy, bool notify)
 					     CPUFREQ_REMOVE_POLICY, policy);
 
 	down_write(&policy->rwsem);
+	cpufreq_stats_free_table(policy);
 	cpufreq_remove_dev_symlink(policy);
 	kobj = &policy->kobj;
 	cmp = &policy->kobj_unregister;
@@ -1262,6 +1264,8 @@ static int cpufreq_online(unsigned int cpu)
 		ret = cpufreq_add_dev_interface(policy);
 		if (ret)
 			goto out_exit_policy;
+
+		cpufreq_stats_create_table(policy);
 		blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
 				CPUFREQ_CREATE_POLICY, policy);
 
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 5e370a30a964..c6e7f81a0397 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -15,7 +15,7 @@
 #include <linux/slab.h>
 #include <linux/cputime.h>
 
-static spinlock_t cpufreq_stats_lock;
+static DEFINE_SPINLOCK(cpufreq_stats_lock);
 
 struct cpufreq_stats {
 	unsigned int total_trans;
@@ -52,6 +52,9 @@ static ssize_t show_time_in_state(struct cpufreq_policy *policy, char *buf)
 	ssize_t len = 0;
 	int i;
 
+	if (policy->fast_switch_enabled)
+		return 0;
+
 	cpufreq_stats_update(stats);
 	for (i = 0; i < stats->state_num; i++) {
 		len += sprintf(buf + len, "%u %llu\n", stats->freq_table[i],
@@ -68,6 +71,9 @@ static ssize_t show_trans_table(struct cpufreq_policy *policy, char *buf)
 	ssize_t len = 0;
 	int i, j;
 
+	if (policy->fast_switch_enabled)
+		return 0;
+
 	len += snprintf(buf + len, PAGE_SIZE - len, "   From  :    To\n");
 	len += snprintf(buf + len, PAGE_SIZE - len, "         : ");
 	for (i = 0; i < stats->state_num; i++) {
@@ -130,7 +136,7 @@ static int freq_table_get_index(struct cpufreq_stats *stats, unsigned int freq)
 	return -1;
 }
 
-static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
+void cpufreq_stats_free_table(struct cpufreq_policy *policy)
 {
 	struct cpufreq_stats *stats = policy->stats;
 
@@ -146,20 +152,7 @@ static void __cpufreq_stats_free_table(struct cpufreq_policy *policy)
 	policy->stats = NULL;
 }
 
-static void cpufreq_stats_free_table(unsigned int cpu)
-{
-	struct cpufreq_policy *policy;
-
-	policy = cpufreq_cpu_get(cpu);
-	if (!policy)
-		return;
-
-	__cpufreq_stats_free_table(policy);
-
-	cpufreq_cpu_put(policy);
-}
-
-static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
+void cpufreq_stats_create_table(struct cpufreq_policy *policy)
 {
 	unsigned int i = 0, count = 0, ret = -ENOMEM;
 	struct cpufreq_stats *stats;
@@ -170,15 +163,15 @@ static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
 	/* We need cpufreq table for creating stats table */
 	table = cpufreq_frequency_get_table(cpu);
 	if (unlikely(!table))
-		return 0;
+		return;
 
 	/* stats already initialized */
 	if (policy->stats)
-		return -EEXIST;
+		return;
 
 	stats = kzalloc(sizeof(*stats), GFP_KERNEL);
 	if (!stats)
-		return -ENOMEM;
+		return;
 
 	/* Find total allocation size */
 	cpufreq_for_each_valid_entry(pos, table)
@@ -215,80 +208,32 @@ static int __cpufreq_stats_create_table(struct cpufreq_policy *policy)
 	policy->stats = stats;
 	ret = sysfs_create_group(&policy->kobj, &stats_attr_group);
 	if (!ret)
-		return 0;
+		return;
 
 	/* We failed, release resources */
 	policy->stats = NULL;
 	kfree(stats->time_in_state);
 free_stat:
 	kfree(stats);
-
-	return ret;
-}
-
-static void cpufreq_stats_create_table(unsigned int cpu)
-{
-	struct cpufreq_policy *policy;
-
-	/*
-	 * "likely(!policy)" because normally cpufreq_stats will be registered
-	 * before cpufreq driver
-	 */
-	policy = cpufreq_cpu_get(cpu);
-	if (likely(!policy))
-		return;
-
-	__cpufreq_stats_create_table(policy);
-
-	cpufreq_cpu_put(policy);
 }
 
-static int cpufreq_stat_notifier_policy(struct notifier_block *nb,
-		unsigned long val, void *data)
+void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
+				     unsigned int new_freq)
 {
-	int ret = 0;
-	struct cpufreq_policy *policy = data;
-
-	if (val == CPUFREQ_CREATE_POLICY)
-		ret = __cpufreq_stats_create_table(policy);
-	else if (val == CPUFREQ_REMOVE_POLICY)
-		__cpufreq_stats_free_table(policy);
-
-	return ret;
-}
-
-static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
-		unsigned long val, void *data)
-{
-	struct cpufreq_freqs *freq = data;
-	struct cpufreq_policy *policy = cpufreq_cpu_get(freq->cpu);
-	struct cpufreq_stats *stats;
+	struct cpufreq_stats *stats = policy->stats;
 	int old_index, new_index;
 
-	if (!policy) {
-		pr_err("%s: No policy found\n", __func__);
-		return 0;
-	}
-
-	if (val != CPUFREQ_POSTCHANGE)
-		goto put_policy;
-
-	if (!policy->stats) {
+	if (!stats) {
 		pr_debug("%s: No stats found\n", __func__);
-		goto put_policy;
+		return;
 	}
 
-	stats = policy->stats;
-
 	old_index = stats->last_index;
-	new_index = freq_table_get_index(stats, freq->new);
+	new_index = freq_table_get_index(stats, new_freq);
 
 	/* We can't do stats->time_in_state[-1]= .. */
-	if (old_index == -1 || new_index == -1)
-		goto put_policy;
-
-	if (old_index == new_index)
-		goto put_policy;
+	if (old_index == -1 || new_index == -1 || old_index == new_index)
+		return;
 
 	cpufreq_stats_update(stats);
 
@@ -297,61 +242,4 @@ static int cpufreq_stat_notifier_trans(struct notifier_block *nb,
 	stats->trans_table[old_index * stats->max_state + new_index]++;
 #endif
 	stats->total_trans++;
-
-put_policy:
-	cpufreq_cpu_put(policy);
-	return 0;
 }
-
-static struct notifier_block notifier_policy_block = {
-	.notifier_call = cpufreq_stat_notifier_policy
-};
-
-static struct notifier_block notifier_trans_block = {
-	.notifier_call = cpufreq_stat_notifier_trans
-};
-
-static int __init cpufreq_stats_init(void)
-{
-	int ret;
-	unsigned int cpu;
-
-	spin_lock_init(&cpufreq_stats_lock);
-	ret = cpufreq_register_notifier(&notifier_policy_block,
-				CPUFREQ_POLICY_NOTIFIER);
-	if (ret)
-		return ret;
-
-	for_each_online_cpu(cpu)
-		cpufreq_stats_create_table(cpu);
-
-	ret = cpufreq_register_notifier(&notifier_trans_block,
-				CPUFREQ_TRANSITION_NOTIFIER);
-	if (ret) {
-		cpufreq_unregister_notifier(&notifier_policy_block,
-				CPUFREQ_POLICY_NOTIFIER);
-		for_each_online_cpu(cpu)
-			cpufreq_stats_free_table(cpu);
-		return ret;
-	}
-
-	return 0;
-}
-static void __exit cpufreq_stats_exit(void)
-{
-	unsigned int cpu;
-
-	cpufreq_unregister_notifier(&notifier_policy_block,
-			CPUFREQ_POLICY_NOTIFIER);
-	cpufreq_unregister_notifier(&notifier_trans_block,
-			CPUFREQ_TRANSITION_NOTIFIER);
-	for_each_online_cpu(cpu)
-		cpufreq_stats_free_table(cpu);
-}
-
-MODULE_AUTHOR("Zou Nan hai <nanhai.zou@intel.com>");
-MODULE_DESCRIPTION("Export cpufreq stats via sysfs");
-MODULE_LICENSE("GPL");
-
-module_init(cpufreq_stats_init);
-module_exit(cpufreq_stats_exit);
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index fbd696edf5bd..7ed93c310c08 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -185,6 +185,18 @@ static inline unsigned int cpufreq_quick_get_max(unsigned int cpu)
 static inline void disable_cpufreq(void) { }
 #endif
 
+#ifdef CONFIG_CPU_FREQ_STAT
+void cpufreq_stats_create_table(struct cpufreq_policy *policy);
+void cpufreq_stats_free_table(struct cpufreq_policy *policy);
+void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
+				     unsigned int new_freq);
+#else
+static inline void cpufreq_stats_create_table(struct cpufreq_policy *policy) { }
+static inline void cpufreq_stats_free_table(struct cpufreq_policy *policy) { }
+static inline void cpufreq_stats_record_transition(struct cpufreq_policy *policy,
+						   unsigned int new_freq) { }
+#endif /* CONFIG_CPU_FREQ_STAT */
+
 /*********************************************************************
  *                      CPUFREQ DRIVER INTERFACE                     *
  *********************************************************************/
-- 
cgit v1.2.3-55-g7522


From f8bfc116cacbdf7e0e655d8a798a242087ed70a5 Mon Sep 17 00:00:00 2001
From: Viresh Kumar
Date: Fri, 3 Jun 2016 10:58:47 +0530
Subject: cpufreq: Remove cpufreq_frequency_get_table()

Most of the callers of cpufreq_frequency_get_table() already have the
pointer to a valid 'policy' structure and they don't really need to go
through the per-cpu variable first and then a check to validate the
frequency, in order to find the freq-table for the policy.

Directly use the policy->freq_table field instead for them.

Only one user of that API is left after above changes, cpu_cooling.c and
it accesses the freq_table in a racy way as the policy can get freed in
between.

Fix it by using cpufreq_cpu_get() properly.

Since there are no more users of cpufreq_frequency_get_table() left, get
rid of it.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Javi Merino <javi.merino@arm.com> (cpu_cooling.c)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/cpufreq/cpufreq.c             | 38 +++++++++++++----------------------
 drivers/cpufreq/cpufreq_ondemand.c    |  2 +-
 drivers/cpufreq/cpufreq_stats.c       |  3 +--
 drivers/cpufreq/freq_table.c          |  9 +++------
 drivers/cpufreq/ppc_cbe_cpufreq_pmi.c |  3 +--
 drivers/thermal/cpu_cooling.c         | 24 +++++++++++++++++-----
 include/linux/cpufreq.h               |  2 --
 7 files changed, 39 insertions(+), 42 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index c6a14ba239a2..cc252eecc45a 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -126,15 +126,6 @@ struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy)
 }
 EXPORT_SYMBOL_GPL(get_governor_parent_kobj);
 
-struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
-{
-	struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
-
-	return policy && !policy_is_inactive(policy) ?
-		policy->freq_table : NULL;
-}
-EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
-
 static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
 {
 	u64 idle_time;
@@ -1950,7 +1941,7 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
 	if (!cpufreq_driver->target_index)
 		return -EINVAL;
 
-	freq_table = cpufreq_frequency_get_table(policy->cpu);
+	freq_table = policy->freq_table;
 	if (unlikely(!freq_table)) {
 		pr_err("%s: Unable to find freq_table\n", __func__);
 		return -EINVAL;
@@ -2345,26 +2336,25 @@ static struct notifier_block __refdata cpufreq_cpu_notifier = {
  *********************************************************************/
 static int cpufreq_boost_set_sw(int state)
 {
-	struct cpufreq_frequency_table *freq_table;
 	struct cpufreq_policy *policy;
 	int ret = -EINVAL;
 
 	for_each_active_policy(policy) {
-		freq_table = cpufreq_frequency_get_table(policy->cpu);
-		if (freq_table) {
-			ret = cpufreq_frequency_table_cpuinfo(policy,
-							freq_table);
-			if (ret) {
-				pr_err("%s: Policy frequency update failed\n",
-				       __func__);
-				break;
-			}
+		if (!policy->freq_table)
+			continue;
 
-			down_write(&policy->rwsem);
-			policy->user_policy.max = policy->max;
-			cpufreq_governor_limits(policy);
-			up_write(&policy->rwsem);
+		ret = cpufreq_frequency_table_cpuinfo(policy,
+						      policy->freq_table);
+		if (ret) {
+			pr_err("%s: Policy frequency update failed\n",
+			       __func__);
+			break;
 		}
+
+		down_write(&policy->rwsem);
+		policy->user_policy.max = policy->max;
+		cpufreq_governor_limits(policy);
+		up_write(&policy->rwsem);
 	}
 
 	return ret;
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index c84fc2240d49..4d2fe2710c5d 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -113,7 +113,7 @@ static void ondemand_powersave_bias_init(struct cpufreq_policy *policy)
 {
 	struct od_policy_dbs_info *dbs_info = to_dbs_info(policy->governor_data);
 
-	dbs_info->freq_table = cpufreq_frequency_get_table(policy->cpu);
+	dbs_info->freq_table = policy->freq_table;
 	dbs_info->freq_lo = 0;
 }
 
diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index c6e7f81a0397..06d3abdffd3a 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -157,11 +157,10 @@ void cpufreq_stats_create_table(struct cpufreq_policy *policy)
 	unsigned int i = 0, count = 0, ret = -ENOMEM;
 	struct cpufreq_stats *stats;
 	unsigned int alloc_size;
-	unsigned int cpu = policy->cpu;
 	struct cpufreq_frequency_table *pos, *table;
 
 	/* We need cpufreq table for creating stats table */
-	table = cpufreq_frequency_get_table(cpu);
+	table = policy->freq_table;
 	if (unlikely(!table))
 		return;
 
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index 4e5c5dbfed7a..f52b5473b1f4 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -106,12 +106,10 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
  */
 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
 {
-	struct cpufreq_frequency_table *table =
-		cpufreq_frequency_get_table(policy->cpu);
-	if (!table)
+	if (!policy->freq_table)
 		return -ENODEV;
 
-	return cpufreq_frequency_table_verify(policy, table);
+	return cpufreq_frequency_table_verify(policy, policy->freq_table);
 }
 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
 
@@ -210,9 +208,8 @@ EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
 		unsigned int freq)
 {
-	struct cpufreq_frequency_table *pos, *table;
+	struct cpufreq_frequency_table *pos, *table = policy->freq_table;
 
-	table = cpufreq_frequency_get_table(policy->cpu);
 	if (unlikely(!table)) {
 		pr_debug("%s: Unable to find frequency table\n", __func__);
 		return -ENOENT;
diff --git a/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c b/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c
index 7c4cd5c634f2..dc112481a408 100644
--- a/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c
+++ b/drivers/cpufreq/ppc_cbe_cpufreq_pmi.c
@@ -94,7 +94,7 @@ static int pmi_notifier(struct notifier_block *nb,
 				       unsigned long event, void *data)
 {
 	struct cpufreq_policy *policy = data;
-	struct cpufreq_frequency_table *cbe_freqs;
+	struct cpufreq_frequency_table *cbe_freqs = policy->freq_table;
 	u8 node;
 
 	/* Should this really be called for CPUFREQ_ADJUST and CPUFREQ_NOTIFY
@@ -103,7 +103,6 @@ static int pmi_notifier(struct notifier_block *nb,
 	if (event == CPUFREQ_START)
 		return 0;
 
-	cbe_freqs = cpufreq_frequency_get_table(policy->cpu);
 	node = cbe_cpu_to_node(policy->cpu);
 
 	pr_debug("got notified, event=%lu, node=%u\n", event, node);
diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index 6ceac4f2d4b2..4d678cfc81b1 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -787,22 +787,34 @@ __cpufreq_cooling_register(struct device_node *np,
 			const struct cpumask *clip_cpus, u32 capacitance,
 			get_static_t plat_static_func)
 {
+	struct cpufreq_policy *policy;
 	struct thermal_cooling_device *cool_dev;
 	struct cpufreq_cooling_device *cpufreq_dev;
 	char dev_name[THERMAL_NAME_LENGTH];
 	struct cpufreq_frequency_table *pos, *table;
+	struct cpumask temp_mask;
 	unsigned int freq, i, num_cpus;
 	int ret;
 
-	table = cpufreq_frequency_get_table(cpumask_first(clip_cpus));
+	cpumask_and(&temp_mask, clip_cpus, cpu_online_mask);
+	policy = cpufreq_cpu_get(cpumask_first(&temp_mask));
+	if (!policy) {
+		pr_debug("%s: CPUFreq policy not found\n", __func__);
+		return ERR_PTR(-EPROBE_DEFER);
+	}
+
+	table = policy->freq_table;
 	if (!table) {
 		pr_debug("%s: CPUFreq table not found\n", __func__);
-		return ERR_PTR(-EPROBE_DEFER);
+		cool_dev = ERR_PTR(-ENODEV);
+		goto put_policy;
 	}
 
 	cpufreq_dev = kzalloc(sizeof(*cpufreq_dev), GFP_KERNEL);
-	if (!cpufreq_dev)
-		return ERR_PTR(-ENOMEM);
+	if (!cpufreq_dev) {
+		cool_dev = ERR_PTR(-ENOMEM);
+		goto put_policy;
+	}
 
 	num_cpus = cpumask_weight(clip_cpus);
 	cpufreq_dev->time_in_idle = kcalloc(num_cpus,
@@ -892,7 +904,7 @@ __cpufreq_cooling_register(struct device_node *np,
 					  CPUFREQ_POLICY_NOTIFIER);
 	mutex_unlock(&cooling_cpufreq_lock);
 
-	return cool_dev;
+	goto put_policy;
 
 remove_idr:
 	release_idr(&cpufreq_idr, cpufreq_dev->id);
@@ -906,6 +918,8 @@ free_time_in_idle:
 	kfree(cpufreq_dev->time_in_idle);
 free_cdev:
 	kfree(cpufreq_dev);
+put_policy:
+	cpufreq_cpu_put(policy);
 
 	return cool_dev;
 }
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 7ed93c310c08..1342cbc0f25e 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -632,8 +632,6 @@ static inline bool policy_has_boost_freq(struct cpufreq_policy *policy)
 	return false;
 }
 #endif
-/* the following funtion is for cpufreq core use only */
-struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu);
 
 /* the following are really really optional */
 extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
-- 
cgit v1.2.3-55-g7522


From 7ab4aabbaa98fbf9f8967fd93162d675439337e1 Mon Sep 17 00:00:00 2001
From: Viresh Kumar
Date: Fri, 3 Jun 2016 10:58:49 +0530
Subject: cpufreq: Drop freq-table param to cpufreq_frequency_table_target()

The policy already has this pointer set, use it instead.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 Documentation/cpu-freq/cpu-drivers.txt |  1 -
 drivers/cpufreq/amd_freq_sensitivity.c |  3 +--
 drivers/cpufreq/cpufreq.c              |  4 ++--
 drivers/cpufreq/cpufreq_ondemand.c     | 11 +++++------
 drivers/cpufreq/freq_table.c           |  2 +-
 drivers/cpufreq/powernv-cpufreq.c      |  3 +--
 drivers/cpufreq/s3c24xx-cpufreq.c      | 11 +++++------
 drivers/cpufreq/s5pv210-cpufreq.c      |  3 +--
 include/linux/cpufreq.h                |  1 -
 9 files changed, 16 insertions(+), 23 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
index decbb8cb5573..74e812f0719c 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -244,7 +244,6 @@ policy->max, and all other criteria are met. This is helpful for the
 ->verify call.
 
 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
-                                   struct cpufreq_frequency_table *table,
                                    unsigned int target_freq,
                                    unsigned int relation,
                                    unsigned int *index);
diff --git a/drivers/cpufreq/amd_freq_sensitivity.c b/drivers/cpufreq/amd_freq_sensitivity.c
index bc86816693a8..3bea1bb791a9 100644
--- a/drivers/cpufreq/amd_freq_sensitivity.c
+++ b/drivers/cpufreq/amd_freq_sensitivity.c
@@ -92,8 +92,7 @@ static unsigned int amd_powersave_bias_target(struct cpufreq_policy *policy,
 			unsigned int index;
 
 			cpufreq_frequency_table_target(policy,
-				policy->freq_table, policy->cur - 1,
-				CPUFREQ_RELATION_H, &index);
+				policy->cur - 1, CPUFREQ_RELATION_H, &index);
 			freq_next = policy->freq_table[index].frequency;
 		}
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index cc252eecc45a..a28144697128 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1947,8 +1947,8 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
 		return -EINVAL;
 	}
 
-	retval = cpufreq_frequency_table_target(policy, freq_table, target_freq,
-						relation, &index);
+	retval = cpufreq_frequency_table_target(policy, target_freq, relation,
+						&index);
 	if (unlikely(retval)) {
 		pr_err("%s: Unable to find matching freq\n", __func__);
 		return retval;
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index 528353f204fd..2ee476f5a2bd 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -79,20 +79,19 @@ static unsigned int generic_powersave_bias_target(struct cpufreq_policy *policy,
 		return freq_next;
 	}
 
-	cpufreq_frequency_table_target(policy, freq_table, freq_next, relation,
-				       &index);
+	cpufreq_frequency_table_target(policy, freq_next, relation, &index);
 	freq_req = freq_table[index].frequency;
 	freq_reduc = freq_req * od_tuners->powersave_bias / 1000;
 	freq_avg = freq_req - freq_reduc;
 
 	/* Find freq bounds for freq_avg in freq_table */
 	index = 0;
-	cpufreq_frequency_table_target(policy, freq_table, freq_avg,
-				       CPUFREQ_RELATION_H, &index);
+	cpufreq_frequency_table_target(policy, freq_avg, CPUFREQ_RELATION_H,
+				       &index);
 	freq_lo = freq_table[index].frequency;
 	index = 0;
-	cpufreq_frequency_table_target(policy, freq_table, freq_avg,
-				       CPUFREQ_RELATION_L, &index);
+	cpufreq_frequency_table_target(policy, freq_avg, CPUFREQ_RELATION_L,
+				       &index);
 	freq_hi = freq_table[index].frequency;
 
 	/* Find out how long we have to be in hi and lo freqs */
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index f52b5473b1f4..f145b64649ef 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -114,7 +114,6 @@ int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
 
 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
-				   struct cpufreq_frequency_table *table,
 				   unsigned int target_freq,
 				   unsigned int relation,
 				   unsigned int *index)
@@ -128,6 +127,7 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
 		.frequency = 0,
 	};
 	struct cpufreq_frequency_table *pos;
+	struct cpufreq_frequency_table *table = policy->freq_table;
 	unsigned int freq, diff, i = 0;
 
 	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index 54c45368e3f1..bf267c2dfe20 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -760,8 +760,7 @@ void powernv_cpufreq_work_fn(struct work_struct *work)
 		struct cpufreq_policy policy;
 
 		cpufreq_get_policy(&policy, cpu);
-		cpufreq_frequency_table_target(&policy, policy.freq_table,
-					       policy.cur,
+		cpufreq_frequency_table_target(&policy, policy.cur,
 					       CPUFREQ_RELATION_C, &index);
 		powernv_cpufreq_target_index(&policy, index);
 		cpumask_andnot(&mask, &mask, policy.cpus);
diff --git a/drivers/cpufreq/s3c24xx-cpufreq.c b/drivers/cpufreq/s3c24xx-cpufreq.c
index 4567c3cab095..05a9737278f3 100644
--- a/drivers/cpufreq/s3c24xx-cpufreq.c
+++ b/drivers/cpufreq/s3c24xx-cpufreq.c
@@ -293,9 +293,8 @@ static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 		     __func__, policy, target_freq, relation);
 
 	if (ftab) {
-		if (cpufreq_frequency_table_target(policy, ftab,
-						   target_freq, relation,
-						   &index)) {
+		if (cpufreq_frequency_table_target(policy, target_freq,
+						   relation, &index)) {
 			s3c_freq_dbg("%s: table failed\n", __func__);
 			return -EINVAL;
 		}
@@ -323,14 +322,14 @@ static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 		tmp_policy.min = policy->min * 1000;
 		tmp_policy.max = policy->max * 1000;
 		tmp_policy.cpu = policy->cpu;
+		tmp_policy.freq_table = pll_reg;
 
 		/* cpufreq_frequency_table_target uses a pointer to 'index'
 		 * which is the number of the table entry, not the value of
 		 * the table entry's index field. */
 
-		ret = cpufreq_frequency_table_target(&tmp_policy, pll_reg,
-						     target_freq, relation,
-						     &index);
+		ret = cpufreq_frequency_table_target(&tmp_policy, target_freq,
+						     relation, &index);
 
 		if (ret < 0) {
 			pr_err("%s: no PLL available\n", __func__);
diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c
index 06d85917b6d5..6b0cfc3b8c46 100644
--- a/drivers/cpufreq/s5pv210-cpufreq.c
+++ b/drivers/cpufreq/s5pv210-cpufreq.c
@@ -246,8 +246,7 @@ static int s5pv210_target(struct cpufreq_policy *policy, unsigned int index)
 	new_freq = s5pv210_freq_table[index].frequency;
 
 	/* Finding current running level index */
-	if (cpufreq_frequency_table_target(policy, s5pv210_freq_table,
-					   old_freq, CPUFREQ_RELATION_H,
+	if (cpufreq_frequency_table_target(policy, old_freq, CPUFREQ_RELATION_H,
 					   &priv_index)) {
 		ret = -EINVAL;
 		goto exit;
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index 1342cbc0f25e..bdd7f0c035ae 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -598,7 +598,6 @@ int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy);
 
 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
-				   struct cpufreq_frequency_table *table,
 				   unsigned int target_freq,
 				   unsigned int relation,
 				   unsigned int *index);
-- 
cgit v1.2.3-55-g7522


From d218ed773915a2b762d132be6bb765637338c360 Mon Sep 17 00:00:00 2001
From: Viresh Kumar
Date: Fri, 3 Jun 2016 10:58:51 +0530
Subject: cpufreq: Return index from cpufreq_frequency_table_target()

This routine can't fail unless the frequency table is invalid and
doesn't contain any valid entries.

Make it return the index and WARN() in case it is used for an invalid
table.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 Documentation/cpu-freq/cpu-drivers.txt |  7 +++----
 drivers/cpufreq/amd_freq_sensitivity.c |  4 ++--
 drivers/cpufreq/cpufreq.c              |  9 ++-------
 drivers/cpufreq/cpufreq_ondemand.c     | 14 ++++++--------
 drivers/cpufreq/freq_table.c           | 24 +++++++++++++-----------
 drivers/cpufreq/powernv-cpufreq.c      |  4 ++--
 drivers/cpufreq/s3c24xx-cpufreq.c      | 26 ++++++--------------------
 drivers/cpufreq/s5pv210-cpufreq.c      |  7 ++-----
 include/linux/cpufreq.h                |  3 +--
 9 files changed, 37 insertions(+), 61 deletions(-)

(limited to 'include/linux/cpufreq.h')

diff --git a/Documentation/cpu-freq/cpu-drivers.txt b/Documentation/cpu-freq/cpu-drivers.txt
index 74e812f0719c..772b94fde264 100644
--- a/Documentation/cpu-freq/cpu-drivers.txt
+++ b/Documentation/cpu-freq/cpu-drivers.txt
@@ -245,12 +245,11 @@ policy->max, and all other criteria are met. This is helpful for the
 
 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
                                    unsigned int target_freq,
-                                   unsigned int relation,
-                                   unsigned int *index);
+                                   unsigned int relation);
 
 is the corresponding frequency table helper for the ->target
-stage. Just pass the values to this function, and the unsigned int
-index returns the number of the frequency table entry which contains
+stage. Just pass the values to this function, and this function
+returns the number of the frequency table entry which contains
 the frequency the CPU shall be set to.
 
 The following macros can be used as iterators over cpufreq_frequency_table:
diff --git a/drivers/cpufreq/amd_freq_sensitivity.c b/drivers/cpufreq/amd_freq_sensitivity.c
index 3bea1bb791a9..6d5dc04c3a37 100644
--- a/drivers/cpufreq/amd_freq_sensitivity.c
+++ b/drivers/cpufreq/amd_freq_sensitivity.c
@@ -91,8 +91,8 @@ static unsigned int amd_powersave_bias_target(struct cpufreq_policy *policy,
 		else {
 			unsigned int index;
 
-			cpufreq_frequency_table_target(policy,
-				policy->cur - 1, CPUFREQ_RELATION_H, &index);
+			index = cpufreq_frequency_table_target(policy,
+				policy->cur - 1, CPUFREQ_RELATION_H);
 			freq_next = policy->freq_table[index].frequency;
 		}
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 1685e930770f..07c933c6c29a 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -1914,7 +1914,7 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
 			    unsigned int relation)
 {
 	unsigned int old_target_freq = target_freq;
-	int index, retval;
+	int index;
 
 	if (cpufreq_disabled())
 		return -ENODEV;
@@ -1943,12 +1943,7 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
 	if (!cpufreq_driver->target_index)
 		return -EINVAL;
 
-	retval = cpufreq_frequency_table_target(policy, target_freq, relation,
-						&index);
-	if (unlikely(retval)) {
-		pr_err("%s: Unable to find matching freq\n", __func__);
-		return retval;
-	}
+	index = cpufreq_frequency_table_target(policy, target_freq, relation);
 
 	return __target_index(policy, index);
 }
diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
index 2ee476f5a2bd..0c93cd9dee99 100644
--- a/drivers/cpufreq/cpufreq_ondemand.c
+++ b/drivers/cpufreq/cpufreq_ondemand.c
@@ -65,7 +65,7 @@ static unsigned int generic_powersave_bias_target(struct cpufreq_policy *policy,
 {
 	unsigned int freq_req, freq_reduc, freq_avg;
 	unsigned int freq_hi, freq_lo;
-	unsigned int index = 0;
+	unsigned int index;
 	unsigned int delay_hi_us;
 	struct policy_dbs_info *policy_dbs = policy->governor_data;
 	struct od_policy_dbs_info *dbs_info = to_dbs_info(policy_dbs);
@@ -79,19 +79,17 @@ static unsigned int generic_powersave_bias_target(struct cpufreq_policy *policy,
 		return freq_next;
 	}
 
-	cpufreq_frequency_table_target(policy, freq_next, relation, &index);
+	index = cpufreq_frequency_table_target(policy, freq_next, relation);
 	freq_req = freq_table[index].frequency;
 	freq_reduc = freq_req * od_tuners->powersave_bias / 1000;
 	freq_avg = freq_req - freq_reduc;
 
 	/* Find freq bounds for freq_avg in freq_table */
-	index = 0;
-	cpufreq_frequency_table_target(policy, freq_avg, CPUFREQ_RELATION_H,
-				       &index);
+	index = cpufreq_frequency_table_target(policy, freq_avg,
+					       CPUFREQ_RELATION_H);
 	freq_lo = freq_table[index].frequency;
-	index = 0;
-	cpufreq_frequency_table_target(policy, freq_avg, CPUFREQ_RELATION_L,
-				       &index);
+	index = cpufreq_frequency_table_target(policy, freq_avg,
+					       CPUFREQ_RELATION_L);
 	freq_hi = freq_table[index].frequency;
 
 	/* Find out how long we have to be in hi and lo freqs */
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c
index f145b64649ef..eac8bcbdaad1 100644
--- a/drivers/cpufreq/freq_table.c
+++ b/drivers/cpufreq/freq_table.c
@@ -114,9 +114,8 @@ int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
 
 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
-				   unsigned int target_freq,
-				   unsigned int relation,
-				   unsigned int *index)
+				    unsigned int target_freq,
+				    unsigned int relation)
 {
 	struct cpufreq_frequency_table optimal = {
 		.driver_data = ~0,
@@ -129,6 +128,7 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
 	struct cpufreq_frequency_table *pos;
 	struct cpufreq_frequency_table *table = policy->freq_table;
 	unsigned int freq, diff, i = 0;
+	int index;
 
 	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
 					target_freq, relation, policy->cpu);
@@ -192,16 +192,18 @@ int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
 		}
 	}
 	if (optimal.driver_data > i) {
-		if (suboptimal.driver_data > i)
-			return -EINVAL;
-		*index = suboptimal.driver_data;
-	} else
-		*index = optimal.driver_data;
+		if (suboptimal.driver_data > i) {
+			WARN(1, "Invalid frequency table: %d\n", policy->cpu);
+			return 0;
+		}
 
-	pr_debug("target index is %u, freq is:%u kHz\n", *index,
-		 table[*index].frequency);
+		index = suboptimal.driver_data;
+	} else
+		index = optimal.driver_data;
 
-	return 0;
+	pr_debug("target index is %u, freq is:%u kHz\n", index,
+		 table[index].frequency);
+	return index;
 }
 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
 
diff --git a/drivers/cpufreq/powernv-cpufreq.c b/drivers/cpufreq/powernv-cpufreq.c
index bf267c2dfe20..b29c5c20c3a1 100644
--- a/drivers/cpufreq/powernv-cpufreq.c
+++ b/drivers/cpufreq/powernv-cpufreq.c
@@ -760,8 +760,8 @@ void powernv_cpufreq_work_fn(struct work_struct *work)
 		struct cpufreq_policy policy;
 
 		cpufreq_get_policy(&policy, cpu);
-		cpufreq_frequency_table_target(&policy, policy.cur,
-					       CPUFREQ_RELATION_C, &index);
+		index = cpufreq_frequency_table_target(&policy, policy.cur,
+					       CPUFREQ_RELATION_C);
 		powernv_cpufreq_target_index(&policy, index);
 		cpumask_andnot(&mask, &mask, policy.cpus);
 	}
diff --git a/drivers/cpufreq/s3c24xx-cpufreq.c b/drivers/cpufreq/s3c24xx-cpufreq.c
index 05a9737278f3..7b596fa38ad2 100644
--- a/drivers/cpufreq/s3c24xx-cpufreq.c
+++ b/drivers/cpufreq/s3c24xx-cpufreq.c
@@ -293,11 +293,8 @@ static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 		     __func__, policy, target_freq, relation);
 
 	if (ftab) {
-		if (cpufreq_frequency_table_target(policy, target_freq,
-						   relation, &index)) {
-			s3c_freq_dbg("%s: table failed\n", __func__);
-			return -EINVAL;
-		}
+		index = cpufreq_frequency_table_target(policy, target_freq,
+						       relation);
 
 		s3c_freq_dbg("%s: adjust %d to entry %d (%u)\n", __func__,
 			     target_freq, index, ftab[index].frequency);
@@ -314,7 +311,6 @@ static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 		pll = NULL;
 	} else {
 		struct cpufreq_policy tmp_policy;
-		int ret;
 
 		/* we keep the cpu pll table in Hz, to ensure we get an
 		 * accurate value for the PLL output. */
@@ -324,18 +320,12 @@ static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 		tmp_policy.cpu = policy->cpu;
 		tmp_policy.freq_table = pll_reg;
 
-		/* cpufreq_frequency_table_target uses a pointer to 'index'
-		 * which is the number of the table entry, not the value of
+		/* cpufreq_frequency_table_target returns the index
+		 * of the table entry, not the value of
 		 * the table entry's index field. */
 
-		ret = cpufreq_frequency_table_target(&tmp_policy, target_freq,
-						     relation, &index);
-
-		if (ret < 0) {
-			pr_err("%s: no PLL available\n", __func__);
-			goto err_notpossible;
-		}
-
+		index = cpufreq_frequency_table_target(&tmp_policy, target_freq,
+						       relation);
 		pll = pll_reg + index;
 
 		s3c_freq_dbg("%s: target %u => %u\n",
@@ -345,10 +335,6 @@ static int s3c_cpufreq_target(struct cpufreq_policy *policy,
 	}
 
 	return s3c_cpufreq_settarget(policy, target_freq, pll);
-
- err_notpossible:
-	pr_err("no compatible settings for %d\n", target_freq);
-	return -EINVAL;
 }
 
 struct clk *s3c_cpufreq_clk_get(struct device *dev, const char *name)
diff --git a/drivers/cpufreq/s5pv210-cpufreq.c b/drivers/cpufreq/s5pv210-cpufreq.c
index 6b0cfc3b8c46..4f4e9df9b7fc 100644
--- a/drivers/cpufreq/s5pv210-cpufreq.c
+++ b/drivers/cpufreq/s5pv210-cpufreq.c
@@ -246,11 +246,8 @@ static int s5pv210_target(struct cpufreq_policy *policy, unsigned int index)
 	new_freq = s5pv210_freq_table[index].frequency;
 
 	/* Finding current running level index */
-	if (cpufreq_frequency_table_target(policy, old_freq, CPUFREQ_RELATION_H,
-					   &priv_index)) {
-		ret = -EINVAL;
-		goto exit;
-	}
+	priv_index = cpufreq_frequency_table_target(policy, old_freq,
+						    CPUFREQ_RELATION_H);
 
 	arm_volt = dvs_conf[index].arm_volt;
 	int_volt = dvs_conf[index].int_volt;
diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
index bdd7f0c035ae..c378776628b4 100644
--- a/include/linux/cpufreq.h
+++ b/include/linux/cpufreq.h
@@ -599,8 +599,7 @@ int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy);
 
 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
 				   unsigned int target_freq,
-				   unsigned int relation,
-				   unsigned int *index);
+				   unsigned int relation);
 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
 		unsigned int freq);
 
-- 
cgit v1.2.3-55-g7522