[kvm-unit-tests,RFC,05/15] arm/arm64: GICv3: add cpu count
diff mbox

Message ID 1480974406-29345-6-git-send-email-eric.auger@redhat.com
State New
Headers show

Commit Message

Auger Eric Dec. 5, 2016, 9:46 p.m. UTC
Add a new cpu_count field in gicv3_data indicating the
number of redistributors. This will be useful for enumeration
of their resources such as LPI pending tables.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
---
 lib/arm/asm/gic-v3.h | 1 +
 lib/arm/gic-v3.c     | 2 ++
 2 files changed, 3 insertions(+)

Comments

Andrew Jones Dec. 6, 2016, 9:29 a.m. UTC | #1
On Mon, Dec 05, 2016 at 10:46:36PM +0100, Eric Auger wrote:
> Add a new cpu_count field in gicv3_data indicating the
> number of redistributors. This will be useful for enumeration
> of their resources such as LPI pending tables.

I'm fine with the additional state, but just curious, will it
ever be possible for gicv3.cpu_count != nr_cpus?

> 
> Signed-off-by: Eric Auger <eric.auger@redhat.com>
> ---
>  lib/arm/asm/gic-v3.h | 1 +
>  lib/arm/gic-v3.c     | 2 ++
>  2 files changed, 3 insertions(+)
> 
> diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
> index ed330af..039b7c2 100644
> --- a/lib/arm/asm/gic-v3.h
> +++ b/lib/arm/asm/gic-v3.h
> @@ -58,6 +58,7 @@ struct gicv3_data {
>  	void *dist_base;
>  	void *redist_base[NR_CPUS];
>  	unsigned int irq_nr;
> +	unsigned int cpu_count;
>  };
>  extern struct gicv3_data gicv3_data;
>  
> diff --git a/lib/arm/gic-v3.c b/lib/arm/gic-v3.c
> index 6246221..9921f4d 100644
> --- a/lib/arm/gic-v3.c
> +++ b/lib/arm/gic-v3.c
> @@ -12,12 +12,14 @@ void gicv3_set_redist_base(size_t stride)
>  	void *ptr = gicv3_data.redist_base[0];
>  	u64 typer;
>  
> +	gicv3_data.cpu_count = 0;
>  	do {
>  		typer = gicv3_read_typer(ptr + GICR_TYPER);
>  		if ((typer >> 32) == aff) {
>  			gicv3_redist_base() = ptr;
>  			return;
>  		}
> +		gicv3_data.cpu_count++;
>  		ptr += stride; /* skip RD_base, SGI_base, etc. */
>  	} while (!(typer & GICR_TYPER_LAST));
>  
> -- 
> 2.5.5
> 
>
Andre Przywara Dec. 6, 2016, 9:32 a.m. UTC | #2
Hi,

On 06/12/16 09:29, Andrew Jones wrote:
> On Mon, Dec 05, 2016 at 10:46:36PM +0100, Eric Auger wrote:
>> Add a new cpu_count field in gicv3_data indicating the
>> number of redistributors. This will be useful for enumeration
>> of their resources such as LPI pending tables.
> 
> I'm fine with the additional state, but just curious, will it
> ever be possible for gicv3.cpu_count != nr_cpus?

If not you are in trouble, so that should in fact be one test.

Which brings me to my comment ...

>>
>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>> ---
>>  lib/arm/asm/gic-v3.h | 1 +
>>  lib/arm/gic-v3.c     | 2 ++
>>  2 files changed, 3 insertions(+)
>>
>> diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
>> index ed330af..039b7c2 100644
>> --- a/lib/arm/asm/gic-v3.h
>> +++ b/lib/arm/asm/gic-v3.h
>> @@ -58,6 +58,7 @@ struct gicv3_data {
>>  	void *dist_base;
>>  	void *redist_base[NR_CPUS];
>>  	unsigned int irq_nr;
>> +	unsigned int cpu_count;

Should that be called "nr_redists" or the like?
Since this is what it counts in the code below.
Later we can then compare this with nr_cpus to check for a match.

Cheers,
Andre.

>>  };
>>  extern struct gicv3_data gicv3_data;
>>  
>> diff --git a/lib/arm/gic-v3.c b/lib/arm/gic-v3.c
>> index 6246221..9921f4d 100644
>> --- a/lib/arm/gic-v3.c
>> +++ b/lib/arm/gic-v3.c
>> @@ -12,12 +12,14 @@ void gicv3_set_redist_base(size_t stride)
>>  	void *ptr = gicv3_data.redist_base[0];
>>  	u64 typer;
>>  
>> +	gicv3_data.cpu_count = 0;
>>  	do {
>>  		typer = gicv3_read_typer(ptr + GICR_TYPER);
>>  		if ((typer >> 32) == aff) {
>>  			gicv3_redist_base() = ptr;
>>  			return;
>>  		}
>> +		gicv3_data.cpu_count++;
>>  		ptr += stride; /* skip RD_base, SGI_base, etc. */
>>  	} while (!(typer & GICR_TYPER_LAST));
>>  
>> -- 
>> 2.5.5
>>
>>
Auger Eric Dec. 6, 2016, 10:04 a.m. UTC | #3
Hi Andre, Drew,

On 06/12/2016 10:32, Andre Przywara wrote:
> Hi,
> 
> On 06/12/16 09:29, Andrew Jones wrote:
>> On Mon, Dec 05, 2016 at 10:46:36PM +0100, Eric Auger wrote:
>>> Add a new cpu_count field in gicv3_data indicating the
>>> number of redistributors. This will be useful for enumeration
>>> of their resources such as LPI pending tables.
>>
>> I'm fine with the additional state, but just curious, will it
>> ever be possible for gicv3.cpu_count != nr_cpus?
> 
> If not you are in trouble, so that should in fact be one test.
> 
> Which brings me to my comment ...
> 
>>>
>>> Signed-off-by: Eric Auger <eric.auger@redhat.com>
>>> ---
>>>  lib/arm/asm/gic-v3.h | 1 +
>>>  lib/arm/gic-v3.c     | 2 ++
>>>  2 files changed, 3 insertions(+)
>>>
>>> diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
>>> index ed330af..039b7c2 100644
>>> --- a/lib/arm/asm/gic-v3.h
>>> +++ b/lib/arm/asm/gic-v3.h
>>> @@ -58,6 +58,7 @@ struct gicv3_data {
>>>  	void *dist_base;
>>>  	void *redist_base[NR_CPUS];
>>>  	unsigned int irq_nr;
>>> +	unsigned int cpu_count;
> 
> Should that be called "nr_redists" or the like?
> Since this is what it counts in the code below.
> Later we can then compare this with nr_cpus to check for a match.

I fully agree with you suggestion.

Thanks

Eric
> 
> Cheers,
> Andre.
> 
>>>  };
>>>  extern struct gicv3_data gicv3_data;
>>>  
>>> diff --git a/lib/arm/gic-v3.c b/lib/arm/gic-v3.c
>>> index 6246221..9921f4d 100644
>>> --- a/lib/arm/gic-v3.c
>>> +++ b/lib/arm/gic-v3.c
>>> @@ -12,12 +12,14 @@ void gicv3_set_redist_base(size_t stride)
>>>  	void *ptr = gicv3_data.redist_base[0];
>>>  	u64 typer;
>>>  
>>> +	gicv3_data.cpu_count = 0;
>>>  	do {
>>>  		typer = gicv3_read_typer(ptr + GICR_TYPER);
>>>  		if ((typer >> 32) == aff) {
>>>  			gicv3_redist_base() = ptr;
>>>  			return;
>>>  		}
>>> +		gicv3_data.cpu_count++;
>>>  		ptr += stride; /* skip RD_base, SGI_base, etc. */
>>>  	} while (!(typer & GICR_TYPER_LAST));
>>>  
>>> -- 
>>> 2.5.5
>>>
>>>
> --
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Patch
diff mbox

diff --git a/lib/arm/asm/gic-v3.h b/lib/arm/asm/gic-v3.h
index ed330af..039b7c2 100644
--- a/lib/arm/asm/gic-v3.h
+++ b/lib/arm/asm/gic-v3.h
@@ -58,6 +58,7 @@  struct gicv3_data {
 	void *dist_base;
 	void *redist_base[NR_CPUS];
 	unsigned int irq_nr;
+	unsigned int cpu_count;
 };
 extern struct gicv3_data gicv3_data;
 
diff --git a/lib/arm/gic-v3.c b/lib/arm/gic-v3.c
index 6246221..9921f4d 100644
--- a/lib/arm/gic-v3.c
+++ b/lib/arm/gic-v3.c
@@ -12,12 +12,14 @@  void gicv3_set_redist_base(size_t stride)
 	void *ptr = gicv3_data.redist_base[0];
 	u64 typer;
 
+	gicv3_data.cpu_count = 0;
 	do {
 		typer = gicv3_read_typer(ptr + GICR_TYPER);
 		if ((typer >> 32) == aff) {
 			gicv3_redist_base() = ptr;
 			return;
 		}
+		gicv3_data.cpu_count++;
 		ptr += stride; /* skip RD_base, SGI_base, etc. */
 	} while (!(typer & GICR_TYPER_LAST));