diff mbox series

[RFC,4/4] ACPI: processor: refactor acpi_processor_remove: isolate acpi_unmap_cpu under CONFIG_ACPI_HOTPLUG_CPU

Message ID 20240409150536.9933-5-miguel.luis@oracle.com
State New
Headers show
Series ACPI: processor: refactor acpi_processor_{get_info|remove} | expand

Commit Message

Miguel Luis April 9, 2024, 3:05 p.m. UTC
acpi_unmap_cpu is architecture dependent. Isolate it.
The pre-processor guard for detach may now be restricted to
cpu unmap.

Signed-off-by: Miguel Luis <miguel.luis@oracle.com>
---
 drivers/acpi/acpi_processor.c | 13 +++++++++----
 1 file changed, 9 insertions(+), 4 deletions(-)

Comments

Jonathan Cameron April 10, 2024, 1:31 p.m. UTC | #1
On Tue,  9 Apr 2024 15:05:33 +0000
Miguel Luis <miguel.luis@oracle.com> wrote:

> acpi_unmap_cpu is architecture dependent. Isolate it.
> The pre-processor guard for detach may now be restricted to
> cpu unmap.
> 
> Signed-off-by: Miguel Luis <miguel.luis@oracle.com>
Again the why question isn't answered by the patch description.

I assume this is to try and resolve the remove question of releasing
resources that was outstanding on vCPU HP v4 series Russell posted.

I've not looked as closely at the remove path as the add one yet, but
my gut feeling is same issue applies.
This code that runs in here should not be dependent on whether
CONFIG_ACPI_HOTPLUG_CPU is enabled or not.  What we do for the
make disabled flow should not run a few of the steps in 
acpi_processor_remove() we should make that clear by calling
a different function that doesn't have those steps.

> ---
>  drivers/acpi/acpi_processor.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> index c6e2f64a056b..edcd6a8d4735 100644
> --- a/drivers/acpi/acpi_processor.c
> +++ b/drivers/acpi/acpi_processor.c
> @@ -492,6 +492,14 @@ static int acpi_processor_add(struct acpi_device *device,
>  }
>  
>  #ifdef CONFIG_ACPI_HOTPLUG_CPU
> +static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr)
> +{
> +	acpi_unmap_cpu(pr->id);
> +}
> +#else
> +static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr) {}
> +#endif /* CONFIG_ACPI_HOTPLUG_CPU */
> +
>  /* Removal */
>  static void acpi_processor_remove(struct acpi_device *device)
>  {
> @@ -524,7 +532,7 @@ static void acpi_processor_remove(struct acpi_device *device)
>  
>  	/* Remove the CPU. */
>  	arch_unregister_cpu(pr->id);
> -	acpi_unmap_cpu(pr->id);
> +	acpi_processor_hotunplug_unmap_cpu(pr);
>  
>  	cpus_write_unlock();
>  	cpu_maps_update_done();
> @@ -535,7 +543,6 @@ static void acpi_processor_remove(struct acpi_device *device)
>  	free_cpumask_var(pr->throttling.shared_cpu_map);
>  	kfree(pr);
>  }
> -#endif /* CONFIG_ACPI_HOTPLUG_CPU */
>  
>  #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
>  bool __init processor_physically_present(acpi_handle handle)
> @@ -660,9 +667,7 @@ static const struct acpi_device_id processor_device_ids[] = {
>  static struct acpi_scan_handler processor_handler = {
>  	.ids = processor_device_ids,
>  	.attach = acpi_processor_add,
> -#ifdef CONFIG_ACPI_HOTPLUG_CPU
>  	.detach = acpi_processor_remove,
> -#endif
>  	.hotplug = {
>  		.enabled = true,
>  	},
Miguel Luis April 11, 2024, 11:02 a.m. UTC | #2
> On 10 Apr 2024, at 13:31, Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote:
> 
> On Tue,  9 Apr 2024 15:05:33 +0000
> Miguel Luis <miguel.luis@oracle.com> wrote:
> 
>> acpi_unmap_cpu is architecture dependent. Isolate it.
>> The pre-processor guard for detach may now be restricted to
>> cpu unmap.
>> 
>> Signed-off-by: Miguel Luis <miguel.luis@oracle.com>
> Again the why question isn't answered by the patch description.
> 
> I assume this is to try and resolve the remove question of releasing
> resources that was outstanding on vCPU HP v4 series Russell posted.
> 
> I've not looked as closely at the remove path as the add one yet, but
> my gut feeling is same issue applies.
> This code that runs in here should not be dependent on whether
> CONFIG_ACPI_HOTPLUG_CPU is enabled or not.

I agree.

>  What we do for the
> make disabled flow should not run a few of the steps in 
> acpi_processor_remove() we should make that clear by calling
> a different function that doesn't have those steps.
> 

Perhaps this got answered already elsewhere but is it OK for the detach handler
to be out of CONFIG_ACPI_HOTPLUG_CPU ?

Miguel

>> ---
>> drivers/acpi/acpi_processor.c | 13 +++++++++----
>> 1 file changed, 9 insertions(+), 4 deletions(-)
>> 
>> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
>> index c6e2f64a056b..edcd6a8d4735 100644
>> --- a/drivers/acpi/acpi_processor.c
>> +++ b/drivers/acpi/acpi_processor.c
>> @@ -492,6 +492,14 @@ static int acpi_processor_add(struct acpi_device *device,
>> }
>> 
>> #ifdef CONFIG_ACPI_HOTPLUG_CPU
>> +static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr)
>> +{
>> + acpi_unmap_cpu(pr->id);
>> +}
>> +#else
>> +static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr) {}
>> +#endif /* CONFIG_ACPI_HOTPLUG_CPU */
>> +
>> /* Removal */
>> static void acpi_processor_remove(struct acpi_device *device)
>> {
>> @@ -524,7 +532,7 @@ static void acpi_processor_remove(struct acpi_device *device)
>> 
>> /* Remove the CPU. */
>> arch_unregister_cpu(pr->id);
>> - acpi_unmap_cpu(pr->id);
>> + acpi_processor_hotunplug_unmap_cpu(pr);
>> 
>> cpus_write_unlock();
>> cpu_maps_update_done();
>> @@ -535,7 +543,6 @@ static void acpi_processor_remove(struct acpi_device *device)
>> free_cpumask_var(pr->throttling.shared_cpu_map);
>> kfree(pr);
>> }
>> -#endif /* CONFIG_ACPI_HOTPLUG_CPU */
>> 
>> #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
>> bool __init processor_physically_present(acpi_handle handle)
>> @@ -660,9 +667,7 @@ static const struct acpi_device_id processor_device_ids[] = {
>> static struct acpi_scan_handler processor_handler = {
>> .ids = processor_device_ids,
>> .attach = acpi_processor_add,
>> -#ifdef CONFIG_ACPI_HOTPLUG_CPU
>> .detach = acpi_processor_remove,
>> -#endif
>> .hotplug = {
>> .enabled = true,
>> },
> 
>
Jonathan Cameron April 11, 2024, 2:02 p.m. UTC | #3
On Thu, 11 Apr 2024 11:02:37 +0000
Miguel Luis <miguel.luis@oracle.com> wrote:

> > On 10 Apr 2024, at 13:31, Jonathan Cameron <Jonathan.Cameron@Huawei.com> wrote:
> > 
> > On Tue,  9 Apr 2024 15:05:33 +0000
> > Miguel Luis <miguel.luis@oracle.com> wrote:
> >   
> >> acpi_unmap_cpu is architecture dependent. Isolate it.
> >> The pre-processor guard for detach may now be restricted to
> >> cpu unmap.
> >> 
> >> Signed-off-by: Miguel Luis <miguel.luis@oracle.com>  
> > Again the why question isn't answered by the patch description.
> > 
> > I assume this is to try and resolve the remove question of releasing
> > resources that was outstanding on vCPU HP v4 series Russell posted.
> > 
> > I've not looked as closely at the remove path as the add one yet, but
> > my gut feeling is same issue applies.
> > This code that runs in here should not be dependent on whether
> > CONFIG_ACPI_HOTPLUG_CPU is enabled or not.  
> 
> I agree.
> 
> >  What we do for the
> > make disabled flow should not run a few of the steps in 
> > acpi_processor_remove() we should make that clear by calling
> > a different function that doesn't have those steps.
> >   
> 
> Perhaps this got answered already elsewhere but is it OK for the detach handler
> to be out of CONFIG_ACPI_HOTPLUG_CPU ?

There is code that is again specific to CONFIG_ACPI_HOTPLUG_CPU and
code that is specific to the disabling only case.  So I think the conditions
will end up looking pretty similar to the attach path.
> 
> Miguel
> 
> >> ---
> >> drivers/acpi/acpi_processor.c | 13 +++++++++----
> >> 1 file changed, 9 insertions(+), 4 deletions(-)
> >> 
> >> diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
> >> index c6e2f64a056b..edcd6a8d4735 100644
> >> --- a/drivers/acpi/acpi_processor.c
> >> +++ b/drivers/acpi/acpi_processor.c
> >> @@ -492,6 +492,14 @@ static int acpi_processor_add(struct acpi_device *device,
> >> }
> >> 
> >> #ifdef CONFIG_ACPI_HOTPLUG_CPU
> >> +static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr)
> >> +{
> >> + acpi_unmap_cpu(pr->id);
> >> +}
> >> +#else
> >> +static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr) {}
> >> +#endif /* CONFIG_ACPI_HOTPLUG_CPU */
> >> +
> >> /* Removal */
> >> static void acpi_processor_remove(struct acpi_device *device)
> >> {
> >> @@ -524,7 +532,7 @@ static void acpi_processor_remove(struct acpi_device *device)
> >> 
> >> /* Remove the CPU. */
> >> arch_unregister_cpu(pr->id);
> >> - acpi_unmap_cpu(pr->id);
> >> + acpi_processor_hotunplug_unmap_cpu(pr);
> >> 
> >> cpus_write_unlock();
> >> cpu_maps_update_done();
> >> @@ -535,7 +543,6 @@ static void acpi_processor_remove(struct acpi_device *device)
> >> free_cpumask_var(pr->throttling.shared_cpu_map);
> >> kfree(pr);
> >> }
> >> -#endif /* CONFIG_ACPI_HOTPLUG_CPU */
> >> 
> >> #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
> >> bool __init processor_physically_present(acpi_handle handle)
> >> @@ -660,9 +667,7 @@ static const struct acpi_device_id processor_device_ids[] = {
> >> static struct acpi_scan_handler processor_handler = {
> >> .ids = processor_device_ids,
> >> .attach = acpi_processor_add,
> >> -#ifdef CONFIG_ACPI_HOTPLUG_CPU
> >> .detach = acpi_processor_remove,
> >> -#endif
> >> .hotplug = {
> >> .enabled = true,
> >> },  
> > 
> >   
>
diff mbox series

Patch

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index c6e2f64a056b..edcd6a8d4735 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -492,6 +492,14 @@  static int acpi_processor_add(struct acpi_device *device,
 }
 
 #ifdef CONFIG_ACPI_HOTPLUG_CPU
+static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr)
+{
+	acpi_unmap_cpu(pr->id);
+}
+#else
+static void acpi_processor_hotunplug_unmap_cpu(struct acpi_processor *pr) {}
+#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+
 /* Removal */
 static void acpi_processor_remove(struct acpi_device *device)
 {
@@ -524,7 +532,7 @@  static void acpi_processor_remove(struct acpi_device *device)
 
 	/* Remove the CPU. */
 	arch_unregister_cpu(pr->id);
-	acpi_unmap_cpu(pr->id);
+	acpi_processor_hotunplug_unmap_cpu(pr);
 
 	cpus_write_unlock();
 	cpu_maps_update_done();
@@ -535,7 +543,6 @@  static void acpi_processor_remove(struct acpi_device *device)
 	free_cpumask_var(pr->throttling.shared_cpu_map);
 	kfree(pr);
 }
-#endif /* CONFIG_ACPI_HOTPLUG_CPU */
 
 #ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
 bool __init processor_physically_present(acpi_handle handle)
@@ -660,9 +667,7 @@  static const struct acpi_device_id processor_device_ids[] = {
 static struct acpi_scan_handler processor_handler = {
 	.ids = processor_device_ids,
 	.attach = acpi_processor_add,
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
 	.detach = acpi_processor_remove,
-#endif
 	.hotplug = {
 		.enabled = true,
 	},