diff mbox series

[v1,02/10] bus: mhi: core: Move to using high priority workqueue

Message ID 1600480955-16827-3-git-send-email-bbhatt@codeaurora.org
State New
Headers show
Series Bug fixes and improvements for MHI power operations | expand

Commit Message

Bhaumik Bhatt Sept. 19, 2020, 2:02 a.m. UTC
MHI work is currently scheduled on the global/system workqueue and can
encounter delays on a stressed system. To avoid those unforeseen
delays which can hamper bootup or shutdown times, use a dedicated high
priority workqueue instead of the global/system workqueue.

Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>
---
 drivers/bus/mhi/core/init.c | 7 +++++++
 drivers/bus/mhi/core/pm.c   | 2 +-
 include/linux/mhi.h         | 2 ++
 3 files changed, 10 insertions(+), 1 deletion(-)

Comments

Manivannan Sadhasivam Oct. 9, 2020, 3:49 p.m. UTC | #1
On Fri, Sep 18, 2020 at 07:02:27PM -0700, Bhaumik Bhatt wrote:
> MHI work is currently scheduled on the global/system workqueue and can

> encounter delays on a stressed system. To avoid those unforeseen

> delays which can hamper bootup or shutdown times, use a dedicated high

> priority workqueue instead of the global/system workqueue.

> 

> Signed-off-by: Bhaumik Bhatt <bbhatt@codeaurora.org>

> ---

>  drivers/bus/mhi/core/init.c | 7 +++++++

>  drivers/bus/mhi/core/pm.c   | 2 +-

>  include/linux/mhi.h         | 2 ++

>  3 files changed, 10 insertions(+), 1 deletion(-)

> 

> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c

> index 1b4161e..ca32563 100644

> --- a/drivers/bus/mhi/core/init.c

> +++ b/drivers/bus/mhi/core/init.c

> @@ -890,6 +890,11 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,

>  	INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);

>  	init_waitqueue_head(&mhi_cntrl->state_event);

>  

> +	mhi_cntrl->hiprio_wq = alloc_ordered_workqueue

> +				("mhi_hiprio_wq", WQ_MEM_RECLAIM | WQ_HIGHPRI);

> +	if (!mhi_cntrl->hiprio_wq)


Printing an error here would be helpful.

> +		goto error_alloc_cmd;

> +

>  	mhi_cmd = mhi_cntrl->mhi_cmd;

>  	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++)

>  		spin_lock_init(&mhi_cmd->lock);

> @@ -977,10 +982,12 @@ int mhi_register_controller(struct mhi_controller *mhi_cntrl,

>  

>  error_alloc_dev:

>  	kfree(mhi_cntrl->mhi_cmd);

> +	destroy_workqueue(mhi_cntrl->hiprio_wq);


So you're destroying the queue two times? You don't need it here.

>  

>  error_alloc_cmd:

>  	vfree(mhi_cntrl->mhi_chan);

>  	kfree(mhi_cntrl->mhi_event);

> +	destroy_workqueue(mhi_cntrl->hiprio_wq);

>  

>  	return ret;

>  }

> diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c

> index ce4d969..9d4789d 100644

> --- a/drivers/bus/mhi/core/pm.c

> +++ b/drivers/bus/mhi/core/pm.c

> @@ -597,7 +597,7 @@ int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,

>  	list_add_tail(&item->node, &mhi_cntrl->transition_list);

>  	spin_unlock_irqrestore(&mhi_cntrl->transition_lock, flags);

>  

> -	schedule_work(&mhi_cntrl->st_worker);

> +	queue_work(mhi_cntrl->hiprio_wq, &mhi_cntrl->st_worker);

>  

>  	return 0;

>  }

> diff --git a/include/linux/mhi.h b/include/linux/mhi.h

> index fb45a0f..7677676 100644

> --- a/include/linux/mhi.h

> +++ b/include/linux/mhi.h

> @@ -338,6 +338,7 @@ struct mhi_controller_config {

>   * @wlock: Lock for protecting device wakeup

>   * @mhi_link_info: Device bandwidth info

>   * @st_worker: State transition worker

> + * @hiprio_wq: High priority workqueue


For what? Please state the purpose.

Thanks,
Mani

>   * @state_event: State change event

>   * @status_cb: CB function to notify power states of the device (required)

>   * @wake_get: CB function to assert device wake (optional)

> @@ -421,6 +422,7 @@ struct mhi_controller {

>  	spinlock_t wlock;

>  	struct mhi_link_info mhi_link_info;

>  	struct work_struct st_worker;

> +	struct workqueue_struct *hiprio_wq;

>  	wait_queue_head_t state_event;

>  

>  	void (*status_cb)(struct mhi_controller *mhi_cntrl,

> -- 

> The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,

> a Linux Foundation Collaborative Project

>
diff mbox series

Patch

diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 1b4161e..ca32563 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -890,6 +890,11 @@  int mhi_register_controller(struct mhi_controller *mhi_cntrl,
 	INIT_WORK(&mhi_cntrl->st_worker, mhi_pm_st_worker);
 	init_waitqueue_head(&mhi_cntrl->state_event);
 
+	mhi_cntrl->hiprio_wq = alloc_ordered_workqueue
+				("mhi_hiprio_wq", WQ_MEM_RECLAIM | WQ_HIGHPRI);
+	if (!mhi_cntrl->hiprio_wq)
+		goto error_alloc_cmd;
+
 	mhi_cmd = mhi_cntrl->mhi_cmd;
 	for (i = 0; i < NR_OF_CMD_RINGS; i++, mhi_cmd++)
 		spin_lock_init(&mhi_cmd->lock);
@@ -977,10 +982,12 @@  int mhi_register_controller(struct mhi_controller *mhi_cntrl,
 
 error_alloc_dev:
 	kfree(mhi_cntrl->mhi_cmd);
+	destroy_workqueue(mhi_cntrl->hiprio_wq);
 
 error_alloc_cmd:
 	vfree(mhi_cntrl->mhi_chan);
 	kfree(mhi_cntrl->mhi_event);
+	destroy_workqueue(mhi_cntrl->hiprio_wq);
 
 	return ret;
 }
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c
index ce4d969..9d4789d 100644
--- a/drivers/bus/mhi/core/pm.c
+++ b/drivers/bus/mhi/core/pm.c
@@ -597,7 +597,7 @@  int mhi_queue_state_transition(struct mhi_controller *mhi_cntrl,
 	list_add_tail(&item->node, &mhi_cntrl->transition_list);
 	spin_unlock_irqrestore(&mhi_cntrl->transition_lock, flags);
 
-	schedule_work(&mhi_cntrl->st_worker);
+	queue_work(mhi_cntrl->hiprio_wq, &mhi_cntrl->st_worker);
 
 	return 0;
 }
diff --git a/include/linux/mhi.h b/include/linux/mhi.h
index fb45a0f..7677676 100644
--- a/include/linux/mhi.h
+++ b/include/linux/mhi.h
@@ -338,6 +338,7 @@  struct mhi_controller_config {
  * @wlock: Lock for protecting device wakeup
  * @mhi_link_info: Device bandwidth info
  * @st_worker: State transition worker
+ * @hiprio_wq: High priority workqueue
  * @state_event: State change event
  * @status_cb: CB function to notify power states of the device (required)
  * @wake_get: CB function to assert device wake (optional)
@@ -421,6 +422,7 @@  struct mhi_controller {
 	spinlock_t wlock;
 	struct mhi_link_info mhi_link_info;
 	struct work_struct st_worker;
+	struct workqueue_struct *hiprio_wq;
 	wait_queue_head_t state_event;
 
 	void (*status_cb)(struct mhi_controller *mhi_cntrl,