[PATCH v10 3/3] firmware: qcom_scm: Use TASK_IDLE state in wait_for_wq_completion()

Shivendra Pratap posted 3 patches 1 day, 7 hours ago
[PATCH v10 3/3] firmware: qcom_scm: Use TASK_IDLE state in wait_for_wq_completion()
Posted by Shivendra Pratap 1 day, 7 hours ago
From: Unnathi Chalicheemala <unnathi.chalicheemala@oss.qualcomm.com>

When the kernel issues an SMC (Secure Monitor Call) and the firmware
requests the kernel to wait, the waiting thread enters an
uninterruptible (D) state. In case of an extended wait request by the
firmware, any device suspend request, cannot proceed because of the
thread stuck in D state. This blocks the device suspend.

Replace wait_for_completion() with wait_for_completion_state(...,
TASK_IDLE), so that the waiting thread, show up in TASK_IDLE state,
instead of TASK_UNINTERRUPTIBLE (D state). This allows the thread to
block until completion, without blocking the device suspend.

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Unnathi Chalicheemala <unnathi.chalicheemala@oss.qualcomm.com>
Signed-off-by: Shivendra Pratap <shivendra.pratap@oss.qualcomm.com>
---
 drivers/firmware/qcom/qcom_scm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/firmware/qcom/qcom_scm.c b/drivers/firmware/qcom/qcom_scm.c
index ef3d81a5340512a79c252430db5f09cd8c253173..45951c04f377b725cdde4696d834435abd92f015 100644
--- a/drivers/firmware/qcom/qcom_scm.c
+++ b/drivers/firmware/qcom/qcom_scm.c
@@ -2316,7 +2316,7 @@ int qcom_scm_wait_for_wq_completion(u32 wq_ctx)
 	if (IS_ERR(wq))
 		return PTR_ERR(wq);
 
-	wait_for_completion(wq);
+	wait_for_completion_state(wq, TASK_IDLE);
 
 	return 0;
 }

-- 
2.34.1