linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] mfd: vexpress: Handle pending config transactions
@ 2013-04-24 16:31 Pawel Moll
  2013-04-25 13:02 ` Jon Medhurst (Tixy)
  2013-04-25 17:14 ` [PATCH v2] " Pawel Moll
  0 siblings, 2 replies; 6+ messages in thread
From: Pawel Moll @ 2013-04-24 16:31 UTC (permalink / raw)
  To: linux-arm-kernel

The config transactions "scheduler" was hopelessly broken,
repeating completed transaction instead of picking up
next pending one.

Fixed now. Also improved debug messages.

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
---
 drivers/mfd/vexpress-config.c |   31 ++++++++++++++++++++-----------
 1 file changed, 20 insertions(+), 11 deletions(-)

diff --git a/drivers/mfd/vexpress-config.c b/drivers/mfd/vexpress-config.c
index 3c1723aa..4991db3 100644
--- a/drivers/mfd/vexpress-config.c
+++ b/drivers/mfd/vexpress-config.c
@@ -184,13 +184,14 @@ static int vexpress_config_schedule(struct vexpress_config_trans *trans)
 
 	spin_lock_irqsave(&bridge->transactions_lock, flags);
 
-	vexpress_config_dump_trans("Executing", trans);
-
-	if (list_empty(&bridge->transactions))
+	if (list_empty(&bridge->transactions)) {
+		vexpress_config_dump_trans("Executing", trans);
 		status = bridge->info->func_exec(trans->func->func,
 				trans->offset, trans->write, trans->data);
-	else
+	} else {
+		vexpress_config_dump_trans("Queuing", trans);
 		status = VEXPRESS_CONFIG_STATUS_WAIT;
+	}
 
 	switch (status) {
 	case VEXPRESS_CONFIG_STATUS_DONE:
@@ -217,20 +218,28 @@ void vexpress_config_complete(struct vexpress_config_bridge *bridge,
 
 	trans = list_first_entry(&bridge->transactions,
 			struct vexpress_config_trans, list);
+	trans->status = status;
 	vexpress_config_dump_trans("Completed", trans);
 
-	trans->status = status;
 	list_del(&trans->list);
 
-	if (!list_empty(&bridge->transactions)) {
-		vexpress_config_dump_trans("Pending", trans);
+	complete(&trans->completion);
+
+	while (!list_empty(&bridge->transactions)) {
+		trans = list_first_entry(&bridge->transactions,
+				struct vexpress_config_trans, list);
 
-		bridge->info->func_exec(trans->func->func, trans->offset,
-				trans->write, trans->data);
+		vexpress_config_dump_trans("Executing pending", trans);
+		status = bridge->info->func_exec(trans->func->func,
+				trans->offset, trans->write, trans->data);
+
+		if (status == VEXPRESS_CONFIG_STATUS_DONE)
+			vexpress_config_dump_trans("Finished pending", trans);
+		else
+			break;
 	}
-	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
 
-	complete(&trans->completion);
+	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
 }
 EXPORT_SYMBOL(vexpress_config_complete);
 
-- 
1.7.10.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH] mfd: vexpress: Handle pending config transactions
  2013-04-24 16:31 [PATCH] mfd: vexpress: Handle pending config transactions Pawel Moll
@ 2013-04-25 13:02 ` Jon Medhurst (Tixy)
  2013-04-25 14:40   ` Pawel Moll
  2013-04-25 17:14 ` [PATCH v2] " Pawel Moll
  1 sibling, 1 reply; 6+ messages in thread
From: Jon Medhurst (Tixy) @ 2013-04-25 13:02 UTC (permalink / raw)
  To: linux-arm-kernel

On Wed, 2013-04-24 at 17:31 +0100, Pawel Moll wrote:
> The config transactions "scheduler" was hopelessly broken,
> repeating completed transaction instead of picking up
> next pending one.
> 
> Fixed now. Also improved debug messages.
> 
> Signed-off-by: Pawel Moll <pawel.moll@arm.com>
> ---
>  drivers/mfd/vexpress-config.c |   31 ++++++++++++++++++++-----------
>  1 file changed, 20 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/mfd/vexpress-config.c b/drivers/mfd/vexpress-config.c
> index 3c1723aa..4991db3 100644
> --- a/drivers/mfd/vexpress-config.c
> +++ b/drivers/mfd/vexpress-config.c
> @@ -184,13 +184,14 @@ static int vexpress_config_schedule(struct vexpress_config_trans *trans)
>  
>  	spin_lock_irqsave(&bridge->transactions_lock, flags);
>  
> -	vexpress_config_dump_trans("Executing", trans);
> -
> -	if (list_empty(&bridge->transactions))
> +	if (list_empty(&bridge->transactions)) {
> +		vexpress_config_dump_trans("Executing", trans);
>  		status = bridge->info->func_exec(trans->func->func,
>  				trans->offset, trans->write, trans->data);
> -	else
> +	} else {
> +		vexpress_config_dump_trans("Queuing", trans);
>  		status = VEXPRESS_CONFIG_STATUS_WAIT;
> +	}
>  
>  	switch (status) {
>  	case VEXPRESS_CONFIG_STATUS_DONE:
> @@ -217,20 +218,28 @@ void vexpress_config_complete(struct vexpress_config_bridge *bridge,
>  
>  	trans = list_first_entry(&bridge->transactions,
>  			struct vexpress_config_trans, list);
> +	trans->status = status;
>  	vexpress_config_dump_trans("Completed", trans);
>  
> -	trans->status = status;
>  	list_del(&trans->list);
>  
> -	if (!list_empty(&bridge->transactions)) {
> -		vexpress_config_dump_trans("Pending", trans);
> +	complete(&trans->completion);
> +
> +	while (!list_empty(&bridge->transactions)) {
> +		trans = list_first_entry(&bridge->transactions,
> +				struct vexpress_config_trans, list);
>  
> -		bridge->info->func_exec(trans->func->func, trans->offset,
> -				trans->write, trans->data);
> +		vexpress_config_dump_trans("Executing pending", trans);
> +		status = bridge->info->func_exec(trans->func->func,
> +				trans->offset, trans->write, trans->data);
> +
> +		if (status == VEXPRESS_CONFIG_STATUS_DONE)
> +			vexpress_config_dump_trans("Finished pending", trans);
> +		else
> +			break;

For each transaction we execute in this loop, don't we also need to do
the actions vexpress_config_complete does? E.g.

	trans->status = status;
	list_del(&trans->list);
	complete(&trans->completion);

except in the case status==VEXPRESS_CONFIG_STATUS_WAIT.

Or, does the call to func_exec cause vexpress_config_complete() to be
called later? (It hadn't better be called synchronously or we get a
deadlock).

Actually, if it is called later, there is still a problem because if the
call to func_exec returns VEXPRESS_CONFIG_STATUS_DONE then the
transaction is left on the list and the while loop will try and execute
it again.

>  	}
> -	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
>  
> -	complete(&trans->completion);
> +	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
>  }
>  EXPORT_SYMBOL(vexpress_config_complete);
>  

-- 
Tixy

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH] mfd: vexpress: Handle pending config transactions
  2013-04-25 13:02 ` Jon Medhurst (Tixy)
@ 2013-04-25 14:40   ` Pawel Moll
  0 siblings, 0 replies; 6+ messages in thread
From: Pawel Moll @ 2013-04-25 14:40 UTC (permalink / raw)
  To: linux-arm-kernel

On Thu, 2013-04-25 at 14:02 +0100, Jon Medhurst (Tixy) wrote:
> > +	while (!list_empty(&bridge->transactions)) {
> > +		trans = list_first_entry(&bridge->transactions,
> > +				struct vexpress_config_trans, list);
> >  
> > -		bridge->info->func_exec(trans->func->func, trans->offset,
> > -				trans->write, trans->data);
> > +		vexpress_config_dump_trans("Executing pending", trans);
> > +		status = bridge->info->func_exec(trans->func->func,
> > +				trans->offset, trans->write, trans->data);
> > +
> > +		if (status == VEXPRESS_CONFIG_STATUS_DONE)
> > +			vexpress_config_dump_trans("Finished pending", trans);
> > +		else
> > +			break;
> 
> For each transaction we execute in this loop, don't we also need to do
> the actions vexpress_config_complete does? E.g.
> 
> 	trans->status = status;
> 	list_del(&trans->list);
> 	complete(&trans->completion);
> 
> except in the case status==VEXPRESS_CONFIG_STATUS_WAIT.

You're completely right. I shouldn't have write this code as the last
thing in the afternoon...

Will send v2.

Pawe?

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v2] mfd: vexpress: Handle pending config transactions
  2013-04-24 16:31 [PATCH] mfd: vexpress: Handle pending config transactions Pawel Moll
  2013-04-25 13:02 ` Jon Medhurst (Tixy)
@ 2013-04-25 17:14 ` Pawel Moll
  2013-04-26 10:51   ` Jon Medhurst (Tixy)
  2013-04-26 14:13   ` Samuel Ortiz
  1 sibling, 2 replies; 6+ messages in thread
From: Pawel Moll @ 2013-04-25 17:14 UTC (permalink / raw)
  To: linux-arm-kernel

The config transactions "scheduler" was hopelessly broken,
repeating completed transaction instead of picking up
next pending one.

Fixed now. Also improved debug messages.

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
---
 drivers/mfd/vexpress-config.c |   35 +++++++++++++++++++++--------------
 1 file changed, 21 insertions(+), 14 deletions(-)

diff --git a/drivers/mfd/vexpress-config.c b/drivers/mfd/vexpress-config.c
index 3c1723aa..84ce6b9 100644
--- a/drivers/mfd/vexpress-config.c
+++ b/drivers/mfd/vexpress-config.c
@@ -184,13 +184,14 @@ static int vexpress_config_schedule(struct vexpress_config_trans *trans)
 
 	spin_lock_irqsave(&bridge->transactions_lock, flags);
 
-	vexpress_config_dump_trans("Executing", trans);
-
-	if (list_empty(&bridge->transactions))
+	if (list_empty(&bridge->transactions)) {
+		vexpress_config_dump_trans("Executing", trans);
 		status = bridge->info->func_exec(trans->func->func,
 				trans->offset, trans->write, trans->data);
-	else
+	} else {
+		vexpress_config_dump_trans("Queuing", trans);
 		status = VEXPRESS_CONFIG_STATUS_WAIT;
+	}
 
 	switch (status) {
 	case VEXPRESS_CONFIG_STATUS_DONE:
@@ -212,25 +213,31 @@ void vexpress_config_complete(struct vexpress_config_bridge *bridge,
 {
 	struct vexpress_config_trans *trans;
 	unsigned long flags;
+	const char *message = "Completed";
 
 	spin_lock_irqsave(&bridge->transactions_lock, flags);
 
 	trans = list_first_entry(&bridge->transactions,
 			struct vexpress_config_trans, list);
-	vexpress_config_dump_trans("Completed", trans);
-
 	trans->status = status;
-	list_del(&trans->list);
 
-	if (!list_empty(&bridge->transactions)) {
-		vexpress_config_dump_trans("Pending", trans);
+	do {
+		vexpress_config_dump_trans(message, trans);
+		list_del(&trans->list);
+		complete(&trans->completion);
 
-		bridge->info->func_exec(trans->func->func, trans->offset,
-				trans->write, trans->data);
-	}
-	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
+		if (list_empty(&bridge->transactions))
+			break;
+
+		trans = list_first_entry(&bridge->transactions,
+				struct vexpress_config_trans, list);
+		vexpress_config_dump_trans("Executing pending", trans);
+		trans->status = bridge->info->func_exec(trans->func->func,
+				trans->offset, trans->write, trans->data);
+		message = "Finished pending";
+	} while (trans->status == VEXPRESS_CONFIG_STATUS_DONE);
 
-	complete(&trans->completion);
+	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
 }
 EXPORT_SYMBOL(vexpress_config_complete);
 
-- 
1.7.10.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v2] mfd: vexpress: Handle pending config transactions
  2013-04-25 17:14 ` [PATCH v2] " Pawel Moll
@ 2013-04-26 10:51   ` Jon Medhurst (Tixy)
  2013-04-26 14:13   ` Samuel Ortiz
  1 sibling, 0 replies; 6+ messages in thread
From: Jon Medhurst (Tixy) @ 2013-04-26 10:51 UTC (permalink / raw)
  To: linux-arm-kernel

On Thu, 2013-04-25 at 18:14 +0100, Pawel Moll wrote:
> The config transactions "scheduler" was hopelessly broken,
> repeating completed transaction instead of picking up
> next pending one.
> 
> Fixed now. Also improved debug messages.
> 
> Signed-off-by: Pawel Moll <pawel.moll@arm.com>

Yes, looks really fixed now. :-)

Reviewed-by: Jon Medhurst <tixy@linaro.org>

> ---
>  drivers/mfd/vexpress-config.c |   35 +++++++++++++++++++++--------------
>  1 file changed, 21 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/mfd/vexpress-config.c b/drivers/mfd/vexpress-config.c
> index 3c1723aa..84ce6b9 100644
> --- a/drivers/mfd/vexpress-config.c
> +++ b/drivers/mfd/vexpress-config.c
> @@ -184,13 +184,14 @@ static int vexpress_config_schedule(struct vexpress_config_trans *trans)
>  
>  	spin_lock_irqsave(&bridge->transactions_lock, flags);
>  
> -	vexpress_config_dump_trans("Executing", trans);
> -
> -	if (list_empty(&bridge->transactions))
> +	if (list_empty(&bridge->transactions)) {
> +		vexpress_config_dump_trans("Executing", trans);
>  		status = bridge->info->func_exec(trans->func->func,
>  				trans->offset, trans->write, trans->data);
> -	else
> +	} else {
> +		vexpress_config_dump_trans("Queuing", trans);
>  		status = VEXPRESS_CONFIG_STATUS_WAIT;
> +	}
>  
>  	switch (status) {
>  	case VEXPRESS_CONFIG_STATUS_DONE:
> @@ -212,25 +213,31 @@ void vexpress_config_complete(struct vexpress_config_bridge *bridge,
>  {
>  	struct vexpress_config_trans *trans;
>  	unsigned long flags;
> +	const char *message = "Completed";
>  
>  	spin_lock_irqsave(&bridge->transactions_lock, flags);
>  
>  	trans = list_first_entry(&bridge->transactions,
>  			struct vexpress_config_trans, list);
> -	vexpress_config_dump_trans("Completed", trans);
> -
>  	trans->status = status;
> -	list_del(&trans->list);
>  
> -	if (!list_empty(&bridge->transactions)) {
> -		vexpress_config_dump_trans("Pending", trans);
> +	do {
> +		vexpress_config_dump_trans(message, trans);
> +		list_del(&trans->list);
> +		complete(&trans->completion);
>  
> -		bridge->info->func_exec(trans->func->func, trans->offset,
> -				trans->write, trans->data);
> -	}
> -	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
> +		if (list_empty(&bridge->transactions))
> +			break;
> +
> +		trans = list_first_entry(&bridge->transactions,
> +				struct vexpress_config_trans, list);
> +		vexpress_config_dump_trans("Executing pending", trans);
> +		trans->status = bridge->info->func_exec(trans->func->func,
> +				trans->offset, trans->write, trans->data);
> +		message = "Finished pending";
> +	} while (trans->status == VEXPRESS_CONFIG_STATUS_DONE);
>  
> -	complete(&trans->completion);
> +	spin_unlock_irqrestore(&bridge->transactions_lock, flags);
>  }
>  EXPORT_SYMBOL(vexpress_config_complete);
>  

^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v2] mfd: vexpress: Handle pending config transactions
  2013-04-25 17:14 ` [PATCH v2] " Pawel Moll
  2013-04-26 10:51   ` Jon Medhurst (Tixy)
@ 2013-04-26 14:13   ` Samuel Ortiz
  1 sibling, 0 replies; 6+ messages in thread
From: Samuel Ortiz @ 2013-04-26 14:13 UTC (permalink / raw)
  To: linux-arm-kernel

Hi Pawel,

On Thu, Apr 25, 2013 at 06:14:51PM +0100, Pawel Moll wrote:
> The config transactions "scheduler" was hopelessly broken,
> repeating completed transaction instead of picking up
> next pending one.
> 
> Fixed now. Also improved debug messages.
> 
> Signed-off-by: Pawel Moll <pawel.moll@arm.com>
> ---
>  drivers/mfd/vexpress-config.c |   35 +++++++++++++++++++++--------------
>  1 file changed, 21 insertions(+), 14 deletions(-)
Applied and pushed, thanks.

Cheers,
Samuel.

-- 
Intel Open Source Technology Centre
http://oss.intel.com/

^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-04-26 14:13 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-04-24 16:31 [PATCH] mfd: vexpress: Handle pending config transactions Pawel Moll
2013-04-25 13:02 ` Jon Medhurst (Tixy)
2013-04-25 14:40   ` Pawel Moll
2013-04-25 17:14 ` [PATCH v2] " Pawel Moll
2013-04-26 10:51   ` Jon Medhurst (Tixy)
2013-04-26 14:13   ` Samuel Ortiz

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).