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-rw-r--r--drivers/base/power/opp/core.c114
-rw-r--r--drivers/base/power/opp/cpu.c22
-rw-r--r--drivers/clk/tegra/clk-dfll.c17
-rw-r--r--drivers/cpufreq/exynos5440-cpufreq.c5
-rw-r--r--drivers/cpufreq/imx6q-cpufreq.c10
-rw-r--r--drivers/cpufreq/mt8173-cpufreq.c8
-rw-r--r--drivers/cpufreq/omap-cpufreq.c4
-rw-r--r--drivers/devfreq/devfreq.c14
-rw-r--r--drivers/devfreq/exynos-bus.c14
-rw-r--r--drivers/devfreq/governor_passive.c4
-rw-r--r--drivers/devfreq/rk3399_dmc.c16
-rw-r--r--drivers/devfreq/tegra-devfreq.c4
-rw-r--r--drivers/thermal/cpu_cooling.c11
-rw-r--r--drivers/thermal/devfreq_cooling.c15
14 files changed, 108 insertions, 150 deletions
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index 9870ee54d708..a6efa818029a 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -40,6 +40,8 @@ do { \
"opp_table_lock protection"); \
} while (0)
+static void dev_pm_opp_get(struct dev_pm_opp *opp);
+
static struct opp_device *_find_opp_dev(const struct device *dev,
struct opp_table *opp_table)
{
@@ -94,21 +96,13 @@ struct opp_table *_find_opp_table(struct device *dev)
* return 0
*
* This is useful only for devices with single power supply.
- *
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. This means that opp which could have been fetched by
- * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are
- * under RCU lock. The pointer returned by the opp_find_freq family must be
- * used in the same section as the usage of this function with the pointer
- * prior to unlocking with rcu_read_unlock() to maintain the integrity of the
- * pointer.
*/
unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
{
struct dev_pm_opp *tmp_opp;
unsigned long v = 0;
- opp_rcu_lockdep_assert();
+ rcu_read_lock();
tmp_opp = rcu_dereference(opp);
if (IS_ERR_OR_NULL(tmp_opp))
@@ -116,6 +110,7 @@ unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp)
else
v = tmp_opp->supplies[0].u_volt;
+ rcu_read_unlock();
return v;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage);
@@ -126,21 +121,13 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_voltage);
*
* Return: frequency in hertz corresponding to the opp, else
* return 0
- *
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. This means that opp which could have been fetched by
- * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are
- * under RCU lock. The pointer returned by the opp_find_freq family must be
- * used in the same section as the usage of this function with the pointer
- * prior to unlocking with rcu_read_unlock() to maintain the integrity of the
- * pointer.
*/
unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp)
{
struct dev_pm_opp *tmp_opp;
unsigned long f = 0;
- opp_rcu_lockdep_assert();
+ rcu_read_lock();
tmp_opp = rcu_dereference(opp);
if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available)
@@ -148,6 +135,7 @@ unsigned long dev_pm_opp_get_freq(struct dev_pm_opp *opp)
else
f = tmp_opp->rate;
+ rcu_read_unlock();
return f;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
@@ -161,20 +149,13 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_freq);
* quickly. Running on them for longer times may overheat the chip.
*
* Return: true if opp is turbo opp, else false.
- *
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. This means that opp which could have been fetched by
- * opp_find_freq_{exact,ceil,floor} functions is valid as long as we are
- * under RCU lock. The pointer returned by the opp_find_freq family must be
- * used in the same section as the usage of this function with the pointer
- * prior to unlocking with rcu_read_unlock() to maintain the integrity of the
- * pointer.
*/
bool dev_pm_opp_is_turbo(struct dev_pm_opp *opp)
{
struct dev_pm_opp *tmp_opp;
+ bool turbo;
- opp_rcu_lockdep_assert();
+ rcu_read_lock();
tmp_opp = rcu_dereference(opp);
if (IS_ERR_OR_NULL(tmp_opp) || !tmp_opp->available) {
@@ -182,7 +163,10 @@ bool dev_pm_opp_is_turbo(struct dev_pm_opp *opp)
return false;
}
- return tmp_opp->turbo;
+ turbo = tmp_opp->turbo;
+
+ rcu_read_unlock();
+ return turbo;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_is_turbo);
@@ -410,11 +394,8 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_get_opp_count);
* This provides a mechanism to enable an opp which is not available currently
* or the opposite as well.
*
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. The reason for the same is that the opp pointer which is
- * returned will remain valid for use with opp_get_{voltage, freq} only while
- * under the locked area. The pointer returned must be used prior to unlocking
- * with rcu_read_unlock() to maintain the integrity of the pointer.
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
*/
struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
unsigned long freq,
@@ -423,13 +404,14 @@ struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
struct opp_table *opp_table;
struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
- opp_rcu_lockdep_assert();
+ rcu_read_lock();
opp_table = _find_opp_table(dev);
if (IS_ERR(opp_table)) {
int r = PTR_ERR(opp_table);
dev_err(dev, "%s: OPP table not found (%d)\n", __func__, r);
+ rcu_read_unlock();
return ERR_PTR(r);
}
@@ -437,10 +419,15 @@ struct dev_pm_opp *dev_pm_opp_find_freq_exact(struct device *dev,
if (temp_opp->available == available &&
temp_opp->rate == freq) {
opp = temp_opp;
+
+ /* Increment the reference count of OPP */
+ dev_pm_opp_get(opp);
break;
}
}
+ rcu_read_unlock();
+
return opp;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_exact);
@@ -454,6 +441,9 @@ static noinline struct dev_pm_opp *_find_freq_ceil(struct opp_table *opp_table,
if (temp_opp->available && temp_opp->rate >= *freq) {
opp = temp_opp;
*freq = opp->rate;
+
+ /* Increment the reference count of OPP */
+ dev_pm_opp_get(opp);
break;
}
}
@@ -476,29 +466,33 @@ static noinline struct dev_pm_opp *_find_freq_ceil(struct opp_table *opp_table,
* ERANGE: no match found for search
* ENODEV: if device not found in list of registered devices
*
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. The reason for the same is that the opp pointer which is
- * returned will remain valid for use with opp_get_{voltage, freq} only while
- * under the locked area. The pointer returned must be used prior to unlocking
- * with rcu_read_unlock() to maintain the integrity of the pointer.
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
*/
struct dev_pm_opp *dev_pm_opp_find_freq_ceil(struct device *dev,
unsigned long *freq)
{
struct opp_table *opp_table;
-
- opp_rcu_lockdep_assert();
+ struct dev_pm_opp *opp;
if (!dev || !freq) {
dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
return ERR_PTR(-EINVAL);
}
+ rcu_read_lock();
+
opp_table = _find_opp_table(dev);
- if (IS_ERR(opp_table))
+ if (IS_ERR(opp_table)) {
+ rcu_read_unlock();
return ERR_CAST(opp_table);
+ }
+
+ opp = _find_freq_ceil(opp_table, freq);
- return _find_freq_ceil(opp_table, freq);
+ rcu_read_unlock();
+
+ return opp;
}
EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil);
@@ -517,11 +511,8 @@ EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_ceil);
* ERANGE: no match found for search
* ENODEV: if device not found in list of registered devices
*
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. The reason for the same is that the opp pointer which is
- * returned will remain valid for use with opp_get_{voltage, freq} only while
- * under the locked area. The pointer returned must be used prior to unlocking
- * with rcu_read_unlock() to maintain the integrity of the pointer.
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
*/
struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
unsigned long *freq)
@@ -529,16 +520,18 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
struct opp_table *opp_table;
struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ERANGE);
- opp_rcu_lockdep_assert();
-
if (!dev || !freq) {
dev_err(dev, "%s: Invalid argument freq=%p\n", __func__, freq);
return ERR_PTR(-EINVAL);
}
+ rcu_read_lock();
+
opp_table = _find_opp_table(dev);
- if (IS_ERR(opp_table))
+ if (IS_ERR(opp_table)) {
+ rcu_read_unlock();
return ERR_CAST(opp_table);
+ }
list_for_each_entry_rcu(temp_opp, &opp_table->opp_list, node) {
if (temp_opp->available) {
@@ -549,6 +542,12 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev,
opp = temp_opp;
}
}
+
+ /* Increment the reference count of OPP */
+ if (!IS_ERR(opp))
+ dev_pm_opp_get(opp);
+ rcu_read_unlock();
+
if (!IS_ERR(opp))
*freq = opp->rate;
@@ -736,6 +735,8 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
ret = PTR_ERR(opp);
dev_err(dev, "%s: failed to find OPP for freq %lu (%d)\n",
__func__, freq, ret);
+ if (!IS_ERR(old_opp))
+ dev_pm_opp_put(old_opp);
rcu_read_unlock();
return ret;
}
@@ -747,6 +748,9 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
/* Only frequency scaling */
if (!regulators) {
+ dev_pm_opp_put(opp);
+ if (!IS_ERR(old_opp))
+ dev_pm_opp_put(old_opp);
rcu_read_unlock();
return _generic_set_opp_clk_only(dev, clk, old_freq, freq);
}
@@ -772,6 +776,9 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
data->new_opp.rate = freq;
memcpy(data->new_opp.supplies, opp->supplies, size);
+ dev_pm_opp_put(opp);
+ if (!IS_ERR(old_opp))
+ dev_pm_opp_put(old_opp);
rcu_read_unlock();
return set_opp(data);
@@ -967,6 +974,11 @@ static void _opp_kref_release(struct kref *kref)
dev_pm_opp_put_opp_table(opp_table);
}
+static void dev_pm_opp_get(struct dev_pm_opp *opp)
+{
+ kref_get(&opp->kref);
+}
+
void dev_pm_opp_put(struct dev_pm_opp *opp)
{
kref_put_mutex(&opp->kref, _opp_kref_release, &opp->opp_table->lock);
diff --git a/drivers/base/power/opp/cpu.c b/drivers/base/power/opp/cpu.c
index 8c3434bdb26d..adef788862d5 100644
--- a/drivers/base/power/opp/cpu.c
+++ b/drivers/base/power/opp/cpu.c
@@ -42,11 +42,6 @@
*
* WARNING: It is important for the callers to ensure refreshing their copy of
* the table if any of the mentioned functions have been invoked in the interim.
- *
- * Locking: The internal opp_table and opp structures are RCU protected.
- * Since we just use the regular accessor functions to access the internal data
- * structures, we use RCU read lock inside this function. As a result, users of
- * this function DONOT need to use explicit locks for invoking.
*/
int dev_pm_opp_init_cpufreq_table(struct device *dev,
struct cpufreq_frequency_table **table)
@@ -56,19 +51,13 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
int i, max_opps, ret = 0;
unsigned long rate;
- rcu_read_lock();
-
max_opps = dev_pm_opp_get_opp_count(dev);
- if (max_opps <= 0) {
- ret = max_opps ? max_opps : -ENODATA;
- goto out;
- }
+ if (max_opps <= 0)
+ return max_opps ? max_opps : -ENODATA;
freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC);
- if (!freq_table) {
- ret = -ENOMEM;
- goto out;
- }
+ if (!freq_table)
+ return -ENOMEM;
for (i = 0, rate = 0; i < max_opps; i++, rate++) {
/* find next rate */
@@ -83,6 +72,8 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
/* Is Boost/turbo opp ? */
if (dev_pm_opp_is_turbo(opp))
freq_table[i].flags = CPUFREQ_BOOST_FREQ;
+
+ dev_pm_opp_put(opp);
}
freq_table[i].driver_data = i;
@@ -91,7 +82,6 @@ int dev_pm_opp_init_cpufreq_table(struct device *dev,
*table = &freq_table[0];
out:
- rcu_read_unlock();
if (ret)
kfree(freq_table);
diff --git a/drivers/clk/tegra/clk-dfll.c b/drivers/clk/tegra/clk-dfll.c
index f010562534eb..2c44aeb0b97c 100644
--- a/drivers/clk/tegra/clk-dfll.c
+++ b/drivers/clk/tegra/clk-dfll.c
@@ -633,16 +633,12 @@ static int find_lut_index_for_rate(struct tegra_dfll *td, unsigned long rate)
struct dev_pm_opp *opp;
int i, uv;
- rcu_read_lock();
-
opp = dev_pm_opp_find_freq_ceil(td->soc->dev, &rate);
- if (IS_ERR(opp)) {
- rcu_read_unlock();
+ if (IS_ERR(opp))
return PTR_ERR(opp);
- }
- uv = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ uv = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
for (i = 0; i < td->i2c_lut_size; i++) {
if (regulator_list_voltage(td->vdd_reg, td->i2c_lut[i]) == uv)
@@ -1440,8 +1436,6 @@ static int dfll_build_i2c_lut(struct tegra_dfll *td)
struct dev_pm_opp *opp;
int lut;
- rcu_read_lock();
-
rate = ULONG_MAX;
opp = dev_pm_opp_find_freq_floor(td->soc->dev, &rate);
if (IS_ERR(opp)) {
@@ -1449,6 +1443,7 @@ static int dfll_build_i2c_lut(struct tegra_dfll *td)
goto out;
}
v_max = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
v = td->soc->cvb->min_millivolts * 1000;
lut = find_vdd_map_entry_exact(td, v);
@@ -1465,6 +1460,8 @@ static int dfll_build_i2c_lut(struct tegra_dfll *td)
if (v_opp <= td->soc->cvb->min_millivolts * 1000)
td->dvco_rate_min = dev_pm_opp_get_freq(opp);
+ dev_pm_opp_put(opp);
+
for (;;) {
v += max(1, (v_max - v) / (MAX_DFLL_VOLTAGES - j));
if (v >= v_opp)
@@ -1496,8 +1493,6 @@ static int dfll_build_i2c_lut(struct tegra_dfll *td)
ret = 0;
out:
- rcu_read_unlock();
-
return ret;
}
diff --git a/drivers/cpufreq/exynos5440-cpufreq.c b/drivers/cpufreq/exynos5440-cpufreq.c
index c0f3373706f4..9180d34cc9fc 100644
--- a/drivers/cpufreq/exynos5440-cpufreq.c
+++ b/drivers/cpufreq/exynos5440-cpufreq.c
@@ -118,12 +118,10 @@ static int init_div_table(void)
unsigned int tmp, clk_div, ema_div, freq, volt_id;
struct dev_pm_opp *opp;
- rcu_read_lock();
cpufreq_for_each_entry(pos, freq_tbl) {
opp = dev_pm_opp_find_freq_exact(dvfs_info->dev,
pos->frequency * 1000, true);
if (IS_ERR(opp)) {
- rcu_read_unlock();
dev_err(dvfs_info->dev,
"failed to find valid OPP for %u KHZ\n",
pos->frequency);
@@ -140,6 +138,7 @@ static int init_div_table(void)
/* Calculate EMA */
volt_id = dev_pm_opp_get_voltage(opp);
+
volt_id = (MAX_VOLTAGE - volt_id) / VOLTAGE_STEP;
if (volt_id < PMIC_HIGH_VOLT) {
ema_div = (CPUEMA_HIGH << P0_7_CPUEMA_SHIFT) |
@@ -157,9 +156,9 @@ static int init_div_table(void)
__raw_writel(tmp, dvfs_info->base + XMU_PMU_P0_7 + 4 *
(pos - freq_tbl));
+ dev_pm_opp_put(opp);
}
- rcu_read_unlock();
return 0;
}
diff --git a/drivers/cpufreq/imx6q-cpufreq.c b/drivers/cpufreq/imx6q-cpufreq.c
index ef1fa8145419..7719b02e04f5 100644
--- a/drivers/cpufreq/imx6q-cpufreq.c
+++ b/drivers/cpufreq/imx6q-cpufreq.c
@@ -53,16 +53,15 @@ static int imx6q_set_target(struct cpufreq_policy *policy, unsigned int index)
freq_hz = new_freq * 1000;
old_freq = clk_get_rate(arm_clk) / 1000;
- rcu_read_lock();
opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz);
if (IS_ERR(opp)) {
- rcu_read_unlock();
dev_err(cpu_dev, "failed to find OPP for %ld\n", freq_hz);
return PTR_ERR(opp);
}
volt = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
+
volt_old = regulator_get_voltage(arm_reg);
dev_dbg(cpu_dev, "%u MHz, %ld mV --> %u MHz, %ld mV\n",
@@ -321,14 +320,15 @@ soc_opp_out:
* freq_table initialised from OPP is therefore sorted in the
* same order.
*/
- rcu_read_lock();
opp = dev_pm_opp_find_freq_exact(cpu_dev,
freq_table[0].frequency * 1000, true);
min_volt = dev_pm_opp_get_voltage(opp);
+ dev_pm_opp_put(opp);
opp = dev_pm_opp_find_freq_exact(cpu_dev,
freq_table[--num].frequency * 1000, true);
max_volt = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
+
ret = regulator_set_voltage_time(arm_reg, min_volt, max_volt);
if (ret > 0)
transition_latency += ret * 1000;
diff --git a/drivers/cpufreq/mt8173-cpufreq.c b/drivers/cpufreq/mt8173-cpufreq.c
index 643f43179df1..ab25b1235a5e 100644
--- a/drivers/cpufreq/mt8173-cpufreq.c
+++ b/drivers/cpufreq/mt8173-cpufreq.c
@@ -232,16 +232,14 @@ static int mtk_cpufreq_set_target(struct cpufreq_policy *policy,
freq_hz = freq_table[index].frequency * 1000;
- rcu_read_lock();
opp = dev_pm_opp_find_freq_ceil(cpu_dev, &freq_hz);
if (IS_ERR(opp)) {
- rcu_read_unlock();
pr_err("cpu%d: failed to find OPP for %ld\n",
policy->cpu, freq_hz);
return PTR_ERR(opp);
}
vproc = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
/*
* If the new voltage or the intermediate voltage is higher than the
@@ -411,16 +409,14 @@ static int mtk_cpu_dvfs_info_init(struct mtk_cpu_dvfs_info *info, int cpu)
/* Search a safe voltage for intermediate frequency. */
rate = clk_get_rate(inter_clk);
- rcu_read_lock();
opp = dev_pm_opp_find_freq_ceil(cpu_dev, &rate);
if (IS_ERR(opp)) {
- rcu_read_unlock();
pr_err("failed to get intermediate opp for cpu%d\n", cpu);
ret = PTR_ERR(opp);
goto out_free_opp_table;
}
info->intermediate_voltage = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
info->cpu_dev = cpu_dev;
info->proc_reg = proc_reg;
diff --git a/drivers/cpufreq/omap-cpufreq.c b/drivers/cpufreq/omap-cpufreq.c
index 376e63ca94e8..71e81bbf031b 100644
--- a/drivers/cpufreq/omap-cpufreq.c
+++ b/drivers/cpufreq/omap-cpufreq.c
@@ -63,16 +63,14 @@ static int omap_target(struct cpufreq_policy *policy, unsigned int index)
freq = ret;
if (mpu_reg) {
- rcu_read_lock();
opp = dev_pm_opp_find_freq_ceil(mpu_dev, &freq);
if (IS_ERR(opp)) {
- rcu_read_unlock();
dev_err(mpu_dev, "%s: unable to find MPU OPP for %d\n",
__func__, new_freq);
return -EINVAL;
}
volt = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
tol = volt * OPP_TOLERANCE / 100;
volt_old = regulator_get_voltage(mpu_reg);
}
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index a545c0fee6e1..253525ea17af 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -111,18 +111,16 @@ static void devfreq_set_freq_table(struct devfreq *devfreq)
return;
}
- rcu_read_lock();
for (i = 0, freq = 0; i < profile->max_state; i++, freq++) {
opp = dev_pm_opp_find_freq_ceil(devfreq->dev.parent, &freq);
if (IS_ERR(opp)) {
devm_kfree(devfreq->dev.parent, profile->freq_table);
profile->max_state = 0;
- rcu_read_unlock();
return;
}
+ dev_pm_opp_put(opp);
profile->freq_table[i] = freq;
}
- rcu_read_unlock();
}
/**
@@ -1112,17 +1110,16 @@ static ssize_t available_frequencies_show(struct device *d,
ssize_t count = 0;
unsigned long freq = 0;
- rcu_read_lock();
do {
opp = dev_pm_opp_find_freq_ceil(dev, &freq);
if (IS_ERR(opp))
break;
+ dev_pm_opp_put(opp);
count += scnprintf(&buf[count], (PAGE_SIZE - count - 2),
"%lu ", freq);
freq++;
} while (1);
- rcu_read_unlock();
/* Truncate the trailing space */
if (count)
@@ -1224,11 +1221,8 @@ subsys_initcall(devfreq_init);
* @freq: The frequency given to target function
* @flags: Flags handed from devfreq framework.
*
- * Locking: This function must be called under rcu_read_lock(). opp is a rcu
- * protected pointer. The reason for the same is that the opp pointer which is
- * returned will remain valid for use with opp_get_{voltage, freq} only while
- * under the locked area. The pointer returned must be used prior to unlocking
- * with rcu_read_unlock() to maintain the integrity of the pointer.
+ * The callers are required to call dev_pm_opp_put() for the returned OPP after
+ * use.
*/
struct dev_pm_opp *devfreq_recommended_opp(struct device *dev,
unsigned long *freq,
diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
index 9af86f46fbec..c6d850cddd98 100644
--- a/drivers/devfreq/exynos-bus.c
+++ b/drivers/devfreq/exynos-bus.c
@@ -103,18 +103,17 @@ static int exynos_bus_target(struct device *dev, unsigned long *freq, u32 flags)
int ret = 0;
/* Get new opp-bus instance according to new bus clock */
- rcu_read_lock();
new_opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(new_opp)) {
dev_err(dev, "failed to get recommended opp instance\n");
- rcu_read_unlock();
return PTR_ERR(new_opp);
}
new_freq = dev_pm_opp_get_freq(new_opp);
new_volt = dev_pm_opp_get_voltage(new_opp);
+ dev_pm_opp_put(new_opp);
+
old_freq = bus->curr_freq;
- rcu_read_unlock();
if (old_freq == new_freq)
return 0;
@@ -214,17 +213,16 @@ static int exynos_bus_passive_target(struct device *dev, unsigned long *freq,
int ret = 0;
/* Get new opp-bus instance according to new bus clock */
- rcu_read_lock();
new_opp = devfreq_recommended_opp(dev, freq, flags);
if (IS_ERR(new_opp)) {
dev_err(dev, "failed to get recommended opp instance\n");
- rcu_read_unlock();
return PTR_ERR(new_opp);
}
new_freq = dev_pm_opp_get_freq(new_opp);
+ dev_pm_opp_put(new_opp);
+
old_freq = bus->curr_freq;
- rcu_read_unlock();
if (old_freq == new_freq)
return 0;
@@ -358,16 +356,14 @@ static int exynos_bus_parse_of(struct device_node *np,
rate = clk_get_rate(bus->clk);
- rcu_read_lock();
opp = devfreq_recommended_opp(dev, &rate, 0);
if (IS_ERR(opp)) {
dev_err(dev, "failed to find dev_pm_opp\n");
- rcu_read_unlock();
ret = PTR_ERR(opp);
goto err_opp;
}
bus->curr_freq = dev_pm_opp_get_freq(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
return 0;
diff --git a/drivers/devfreq/governor_passive.c b/drivers/devfreq/governor_passive.c
index 9ef46e2592c4..bd452236dba4 100644
--- a/drivers/devfreq/governor_passive.c
+++ b/drivers/devfreq/governor_passive.c
@@ -59,14 +59,14 @@ static int devfreq_passive_get_target_freq(struct devfreq *devfreq,
* list of parent device. Because in this case, *freq is temporary
* value which is decided by ondemand governor.
*/
- rcu_read_lock();
opp = devfreq_recommended_opp(parent_devfreq->dev.parent, freq, 0);
- rcu_read_unlock();
if (IS_ERR(opp)) {
ret = PTR_ERR(opp);
goto out;
}
+ dev_pm_opp_put(opp);
+
/*
* Get the OPP table's index of decided freqeuncy by governor
* of parent device.
diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
index 27d2f349b53c..40a2499730fc 100644
--- a/drivers/devfreq/rk3399_dmc.c
+++ b/drivers/devfreq/rk3399_dmc.c
@@ -91,17 +91,13 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
unsigned long target_volt, target_rate;
int err;
- rcu_read_lock();
opp = devfreq_recommended_opp(dev, freq, flags);
- if (IS_ERR(opp)) {
- rcu_read_unlock();
+ if (IS_ERR(opp))
return PTR_ERR(opp);
- }
target_rate = dev_pm_opp_get_freq(opp);
target_volt = dev_pm_opp_get_voltage(opp);
-
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
if (dmcfreq->rate == target_rate)
return 0;
@@ -422,15 +418,13 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
data->rate = clk_get_rate(data->dmc_clk);
- rcu_read_lock();
opp = devfreq_recommended_opp(dev, &data->rate, 0);
- if (IS_ERR(opp)) {
- rcu_read_unlock();
+ if (IS_ERR(opp))
return PTR_ERR(opp);
- }
+
data->rate = dev_pm_opp_get_freq(opp);
data->volt = dev_pm_opp_get_voltage(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
rk3399_devfreq_dmc_profile.initial_freq = data->rate;
diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c
index fe9dce0245bf..214fff96fa4a 100644
--- a/drivers/devfreq/tegra-devfreq.c
+++ b/drivers/devfreq/tegra-devfreq.c
@@ -487,15 +487,13 @@ static int tegra_devfreq_target(struct device *dev, unsigned long *freq,
struct dev_pm_opp *opp;
unsigned long rate = *freq * KHZ;
- rcu_read_lock();
opp = devfreq_recommended_opp(dev, &rate, flags);
if (IS_ERR(opp)) {
- rcu_read_unlock();
dev_err(dev, "Failed to find opp for %lu KHz\n", *freq);
return PTR_ERR(opp);
}
rate = dev_pm_opp_get_freq(opp);
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
clk_set_min_rate(tegra->emc_clock, rate);
clk_set_rate(tegra->emc_clock, 0);
diff --git a/drivers/thermal/cpu_cooling.c b/drivers/thermal/cpu_cooling.c
index 9ce0e9eef923..85fdbf762fa0 100644
--- a/drivers/thermal/cpu_cooling.c
+++ b/drivers/thermal/cpu_cooling.c
@@ -297,8 +297,6 @@ static int build_dyn_power_table(struct cpufreq_cooling_device *cpufreq_device,
if (!power_table)
return -ENOMEM;
- rcu_read_lock();
-
for (freq = 0, i = 0;
opp = dev_pm_opp_find_freq_ceil(dev, &freq), !IS_ERR(opp);
freq++, i++) {
@@ -306,13 +304,13 @@ static int build_dyn_power_table(struct cpufreq_cooling_device *cpufreq_device,
u64 power;
if (i >= num_opps) {
- rcu_read_unlock();
ret = -EAGAIN;
goto free_power_table;
}
freq_mhz = freq / 1000000;
voltage_mv = dev_pm_opp_get_voltage(opp) / 1000;
+ dev_pm_opp_put(opp);
/*
* Do the multiplication with MHz and millivolt so as
@@ -328,8 +326,6 @@ static int build_dyn_power_table(struct cpufreq_cooling_device *cpufreq_device,
power_table[i].power = power;
}
- rcu_read_unlock();
-
if (i != num_opps) {
ret = PTR_ERR(opp);
goto free_power_table;
@@ -433,13 +429,10 @@ static int get_static_power(struct cpufreq_cooling_device *cpufreq_device,
return 0;
}
- rcu_read_lock();
-
opp = dev_pm_opp_find_freq_exact(cpufreq_device->cpu_dev, freq_hz,
true);
voltage = dev_pm_opp_get_voltage(opp);
-
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
if (voltage == 0) {
dev_warn_ratelimited(cpufreq_device->cpu_dev,
diff --git a/drivers/thermal/devfreq_cooling.c b/drivers/thermal/devfreq_cooling.c
index 5a737fd5f1aa..ba7a5cd994dc 100644
--- a/drivers/thermal/devfreq_cooling.c
+++ b/drivers/thermal/devfreq_cooling.c
@@ -113,15 +113,15 @@ static int partition_enable_opps(struct devfreq_cooling_device *dfc,
unsigned int freq = dfc->freq_table[i];
bool want_enable = i >= cdev_state ? true : false;
- rcu_read_lock();
opp = dev_pm_opp_find_freq_exact(dev, freq, !want_enable);
- rcu_read_unlock();
if (PTR_ERR(opp) == -ERANGE)
continue;
else if (IS_ERR(opp))
return PTR_ERR(opp);
+ dev_pm_opp_put(opp);
+
if (want_enable)
ret = dev_pm_opp_enable(dev, freq);
else
@@ -221,15 +221,12 @@ get_static_power(struct devfreq_cooling_device *dfc, unsigned long freq)
if (!dfc->power_ops->get_static_power)
return 0;
- rcu_read_lock();
-
opp = dev_pm_opp_find_freq_exact(dev, freq, true);
if (IS_ERR(opp) && (PTR_ERR(opp) == -ERANGE))
opp = dev_pm_opp_find_freq_exact(dev, freq, false);
voltage = dev_pm_opp_get_voltage(opp) / 1000; /* mV */
-
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
if (voltage == 0) {
dev_warn_ratelimited(dev,
@@ -412,18 +409,14 @@ static int devfreq_cooling_gen_tables(struct devfreq_cooling_device *dfc)
unsigned long power_dyn, voltage;
struct dev_pm_opp *opp;
- rcu_read_lock();
-
opp = dev_pm_opp_find_freq_floor(dev, &freq);
if (IS_ERR(opp)) {
- rcu_read_unlock();
ret = PTR_ERR(opp);
goto free_tables;
}
voltage = dev_pm_opp_get_voltage(opp) / 1000; /* mV */
-
- rcu_read_unlock();
+ dev_pm_opp_put(opp);
if (dfc->power_ops) {
power_dyn = get_dynamic_power(dfc, freq, voltage);