From: Xunlei Pang <pang.xun...@linaro.org>
Since we are using cpuidle_driver::safe_state_index directly as the
target state index, it is better to add the sanity check at the point
of registering the driver.
Signed-off-by: Xunlei Pang <pang.xun...@linaro.org>
---
v2->v3:
Move the code to a new cpuidle_coupled_state_verify() depending on
CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED, to avoid using #ifdef in function
bodies. Thanks Rafael's comments on this.
drivers/cpuidle/coupled.c | 22 ++++++++++++++++++++++
drivers/cpuidle/cpuidle.h | 6 ++++++
drivers/cpuidle/driver.c | 4 ++++
3 files changed, 32 insertions(+)
diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c
index 1523e2d..344058f 100644
--- a/drivers/cpuidle/coupled.c
+++ b/drivers/cpuidle/coupled.c
@@ -187,6 +187,28 @@ bool cpuidle_state_is_coupled(struct cpuidle_driver *drv,
int state)
}
/**
+ * cpuidle_coupled_state_verify - check if the coupled states are correctly
set.
+ * @drv: struct cpuidle_driver for the platform
+ *
+ * Returns 0 for valid state values, a negative error code otherwise:
+ * * -EINVAL if any coupled state(safe_state_index) is wrongly set.
+ */
+int cpuidle_coupled_state_verify(struct cpuidle_driver *drv)
+{
+ int i;
+
+ for (i = drv->state_count - 1; i >= 0; i--) {
+ if (cpuidle_state_is_coupled(drv, i) &&
+ (drv->safe_state_index == i ||
+ drv->safe_state_index < 0 ||
+ drv->safe_state_index >= drv->state_count))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/**
* cpuidle_coupled_set_ready - mark a cpu as ready
* @coupled: the struct coupled that contains the current cpu
*/
diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h
index 178c5ad..f87f399 100644
--- a/drivers/cpuidle/cpuidle.h
+++ b/drivers/cpuidle/cpuidle.h
@@ -35,6 +35,7 @@ extern void cpuidle_remove_sysfs(struct cpuidle_device *dev);
#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
bool cpuidle_state_is_coupled(struct cpuidle_driver *drv, int state);
+int cpuidle_coupled_state_verify(struct cpuidle_driver *drv);
int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int next_state);
int cpuidle_coupled_register_device(struct cpuidle_device *dev);
@@ -46,6 +47,11 @@ bool cpuidle_state_is_coupled(struct cpuidle_driver *drv,
int state)
return false;
}
+static inline int cpuidle_coupled_state_verify(struct cpuidle_driver *drv)
+{
+ return 0;
+}
+
static inline int cpuidle_enter_state_coupled(struct cpuidle_device *dev,
struct cpuidle_driver *drv, int next_state)
{
diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c
index 5db1478..389ade4 100644
--- a/drivers/cpuidle/driver.c
+++ b/drivers/cpuidle/driver.c
@@ -227,6 +227,10 @@ static int __cpuidle_register_driver(struct cpuidle_driver
*drv)
if (!drv || !drv->state_count)
return -EINVAL;
+ ret = cpuidle_coupled_state_verify(drv);
+ if (ret)
+ return ret;
+
if (cpuidle_disabled())
return -ENODEV;
--
1.9.1
--
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