Add lockdep checks for holding domain lock in few places where this is required. This might expose misuse even though only file-scope functions use it for now.
Regular lockdep asserts can be entirely discarded by preprocessor, however domain code uses mixed type of lock: spinlock or mutex. This means that these asserts will not be thrown away entirely. Instead, always at least two pointer dereferences (p->lock_ops->assert_held) and probably one function call (assert_held()) will be made. Signed-off-by: Krzysztof Kozlowski <[email protected]> --- drivers/base/power/domain.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/drivers/base/power/domain.c b/drivers/base/power/domain.c index 33467beaeea4..36db9a06f0cc 100644 --- a/drivers/base/power/domain.c +++ b/drivers/base/power/domain.c @@ -40,12 +40,18 @@ static LIST_HEAD(gpd_list); static DEFINE_MUTEX(gpd_list_lock); struct genpd_lock_ops { + void (*assert_held)(struct generic_pm_domain *genpd); void (*lock)(struct generic_pm_domain *genpd); void (*lock_nested)(struct generic_pm_domain *genpd, int depth); int (*lock_interruptible)(struct generic_pm_domain *genpd); void (*unlock)(struct generic_pm_domain *genpd); }; +static void genpd_assert_held_mtx(struct generic_pm_domain *genpd) +{ + lockdep_assert_held(&genpd->mlock); +} + static void genpd_lock_mtx(struct generic_pm_domain *genpd) { mutex_lock(&genpd->mlock); @@ -68,12 +74,18 @@ static void genpd_unlock_mtx(struct generic_pm_domain *genpd) } static const struct genpd_lock_ops genpd_mtx_ops = { + .assert_held = genpd_assert_held_mtx, .lock = genpd_lock_mtx, .lock_nested = genpd_lock_nested_mtx, .lock_interruptible = genpd_lock_interruptible_mtx, .unlock = genpd_unlock_mtx, }; +static void genpd_assert_held_spin(struct generic_pm_domain *genpd) +{ + lockdep_assert_held(&genpd->slock); +} + static void genpd_lock_spin(struct generic_pm_domain *genpd) __acquires(&genpd->slock) { @@ -110,12 +122,14 @@ static void genpd_unlock_spin(struct generic_pm_domain *genpd) } static const struct genpd_lock_ops genpd_spin_ops = { + .assert_held = genpd_assert_held_spin, .lock = genpd_lock_spin, .lock_nested = genpd_lock_nested_spin, .lock_interruptible = genpd_lock_interruptible_spin, .unlock = genpd_unlock_spin, }; +#define genpd_assert_held(p) p->lock_ops->assert_held(p) #define genpd_lock(p) p->lock_ops->lock(p) #define genpd_lock_nested(p, d) p->lock_ops->lock_nested(p, d) #define genpd_lock_interruptible(p) p->lock_ops->lock_interruptible(p) @@ -299,6 +313,8 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on, struct gpd_link *link; unsigned int not_suspended = 0; + genpd_assert_held(genpd); + /* * Do not try to power off the domain in the following situations: * (1) The domain is already in the "power off" state. @@ -385,6 +401,8 @@ static int genpd_power_on(struct generic_pm_domain *genpd, unsigned int depth) struct gpd_link *link; int ret = 0; + genpd_assert_held(genpd); + if (genpd_status_on(genpd)) return 0; @@ -766,6 +784,9 @@ static void genpd_sync_power_off(struct generic_pm_domain *genpd, bool use_lock, { struct gpd_link *link; + if (use_lock) + genpd_assert_held(genpd); + if (!genpd_status_on(genpd) || genpd_is_always_on(genpd)) return; @@ -808,6 +829,9 @@ static void genpd_sync_power_on(struct generic_pm_domain *genpd, bool use_lock, { struct gpd_link *link; + if (use_lock) + genpd_assert_held(genpd); + if (genpd_status_on(genpd)) return; -- 2.9.3
