[PATCH 5.9 081/255] opp: Reduce the size of critical section in _opp_table_kref_release()

Greg Kroah-Hartman
2020-11-17T13:50:05Z

From: Viresh Kumar <viresh.kumar@linaro.org>

[ Upstream commit e0df59de670b48a923246fae1f972317b84b2764 ]

There is a lot of stuff here which can be done outside of the big
opp_table_lock, do that. This helps avoiding few circular dependency
lockdeps around debugfs and interconnects.

Reported-by: Rob Clark <robdclark@gmail.com>
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/opp/core.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 1a95ad40795be..a963df7bd2749 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -1160,6 +1160,10 @@ static void _opp_table_kref_release(struct kref *kref)
struct opp_device *opp_dev, *temp;
int i;

+ /* Drop the lock as soon as we can */
+ list_del(&opp_table->node);
+ mutex_unlock(&opp_table_lock);
+
_of_clear_opp_table(opp_table);

/* Release clk */
@@ -1187,10 +1191,7 @@ static void _opp_table_kref_release(struct kref *kref)

mutex_destroy(&opp_table->genpd_virt_dev_lock);
mutex_destroy(&opp_table->lock);
- list_del(&opp_table->node);
kfree(opp_table);
-
- mutex_unlock(&opp_table_lock);
}

void dev_pm_opp_put_opp_table(struct opp_table *opp_table)
--
2.27.0