Re: [PATCH v3 5/7] acpi/ghes, cxl: Refactor work registration functions to support multiple workqueues

[Jonathan Cameron <Jonathan.Cameron@huawei.com>]

On Tue, 19 Nov 2024 00:39:13 +0000
Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com> wrote:

> Refactor the work registration and unregistration functions in GHES to
> enable reuse across different workqueues. This update lays the foundation
> for integrating additional workqueues in the CXL subsystem for better
> modularity and code reuse.
> 
> Signed-off-by: Smita Koralahalli <Smita.KoralahalliChannabasappa@amd.com>
> ---
>  drivers/acpi/apei/ghes.c | 34 +++++++++++++++++++++++++---------
>  1 file changed, 25 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index 082c409707ba..62ffe6eb5503 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -717,26 +717,42 @@ static void cxl_cper_post_event(enum cxl_event_type event_type,
>  	schedule_work(cxl_cper_work);
>  }
>  
> -int cxl_cper_register_event_work(struct work_struct *work)
> +static int cxl_cper_register_work(struct work_struct **work_ptr,
> +				  spinlock_t *lock,
> +				  struct work_struct *work)

This is a somewhat strange interface.  It doesn't
really do anything particularly useful. I'd be tempted to
just open code this at each call site.


>  {
> -	if (cxl_cper_work)
> +	if (*work_ptr)
>  		return -EINVAL;
>  
> -	guard(spinlock)(&cxl_cper_work_lock);
> -	cxl_cper_work = work;
> +	guard(spinlock)(lock);
> +	*work_ptr = work;
>  	return 0;
>  }
> -EXPORT_SYMBOL_NS_GPL(cxl_cper_register_event_work, CXL);
>  
> -int cxl_cper_unregister_event_work(struct work_struct *work)
> +static int cxl_cper_unregister_work(struct work_struct **work_ptr,
> +				    spinlock_t *lock,
> +				    struct work_struct *work)
>  {
> -	if (cxl_cper_work != work)
> +	if (*work_ptr != work)
As above.

>  		return -EINVAL;
>  
> -	guard(spinlock)(&cxl_cper_work_lock);
> -	cxl_cper_work = NULL;
> +	guard(spinlock)(lock);
> +	*work_ptr = NULL;
>  	return 0;
>  }
> +
> +int cxl_cper_register_event_work(struct work_struct *work)
> +{
> +	return cxl_cper_register_work(&cxl_cper_work, &cxl_cper_work_lock,
> +				      work);
> +}
> +EXPORT_SYMBOL_NS_GPL(cxl_cper_register_event_work, CXL);
> +
> +int cxl_cper_unregister_event_work(struct work_struct *work)
> +{
> +	return cxl_cper_unregister_work(&cxl_cper_work, &cxl_cper_work_lock,
> +					work);
> +}
>  EXPORT_SYMBOL_NS_GPL(cxl_cper_unregister_event_work, CXL);
>  
>  int cxl_cper_kfifo_get(struct cxl_cper_work_data *wd)