Hi Viresh,
[snip]
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index b0de42972b74..89add0d7c017 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);
dev_pm_opp_put(opp);
I think that the dev_pm_opp_put(opp) should be called after if statement If dev_pm_opp_find_freq_ceil() return error, I think the calling of dev_pm_opp_put(opp) is not necessary.
if (IS_ERR(opp)) { devm_kfree(devfreq->dev.parent, profile->freq_table); profile->max_state = 0;
rcu_read_unlock(); return;- rcu_read_unlock();
} /** @@ -1107,9 +1105,9 @@ 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);
dev_pm_opp_put(opp);
ditto.
if (IS_ERR(opp)) break;@@ -1117,7 +1115,6 @@ static ssize_t available_frequencies_show(struct device *d, "%lu ", freq); freq++; } while (1);
- rcu_read_unlock();
/* Truncate the trailing space */ if (count) @@ -1219,11 +1216,8 @@ 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 a8ed7792ece2..49ce38cef460 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();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();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();- 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..671a1e0afc6e 100644 --- a/drivers/devfreq/governor_passive.c +++ b/drivers/devfreq/governor_passive.c @@ -59,9 +59,9 @@ 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();
- dev_pm_opp_put(opp);
ditto.
- if (IS_ERR(opp)) { ret = PTR_ERR(opp); goto out;
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();- rcu_read_unlock();
- dev_pm_opp_put(opp);
clk_set_min_rate(tegra->emc_clock, rate); clk_set_rate(tegra->emc_clock, 0);
[snip]
Best Regards, Chanwoo Choi