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.m...@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
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