[PATCH V2] powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() function

[PATCH V2] powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() function

[Satheesh Rajendran]

Argument "align" in alloc_shared_lppaca() was unused inside the
function. Let's drop it and update code comment for page alignment.

Cc: linux-kernel@vger.kernel.org
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
---

V2:
Added reviewed by Thiago.
Dropped align argument as per Michael suggest.
Modified commit msg.

V1: http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20200609113909.17236-1-sathnaga@linux.vnet.ibm.com/
---
 arch/powerpc/kernel/paca.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
index 8d96169c597e..a174d64d9b4d 100644
--- a/arch/powerpc/kernel/paca.c
+++ b/arch/powerpc/kernel/paca.c
@@ -57,8 +57,8 @@ static void *__init alloc_paca_data(unsigned long size, unsigned long align,
 
 #define LPPACA_SIZE 0x400
 
-static void *__init alloc_shared_lppaca(unsigned long size, unsigned long align,
-					unsigned long limit, int cpu)
+static void *__init alloc_shared_lppaca(unsigned long size, unsigned long limit,
+					int cpu)
 {
 	size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE);
 	static unsigned long shared_lppaca_size;
@@ -68,6 +68,12 @@ static void *__init alloc_shared_lppaca(unsigned long size, unsigned long align,
 	if (!shared_lppaca) {
 		memblock_set_bottom_up(true);
 
+		/* See Documentation/powerpc/ultravisor.rst for mode details
+		 *
+		 * UV/HV data share is in PAGE granularity, In order to
+		 * minimize the number of pages shared and maximize the
+		 * use of a page, let's use page align.
+		 */
 		shared_lppaca =
 			memblock_alloc_try_nid(shared_lppaca_total_size,
 					       PAGE_SIZE, MEMBLOCK_LOW_LIMIT,
@@ -122,7 +128,7 @@ static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
 		return NULL;
 
 	if (is_secure_guest())
-		lp = alloc_shared_lppaca(LPPACA_SIZE, 0x400, limit, cpu);
+		lp = alloc_shared_lppaca(LPPACA_SIZE, limit, cpu);
 	else
 		lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu);
 
-- 
2.26.2

Re: [PATCH V2] powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() function

[Laurent Dufour]

Le 12/06/2020 à 16:29, Satheesh Rajendran a écrit :
> Argument "align" in alloc_shared_lppaca() was unused inside the
> function. Let's drop it and update code comment for page alignment.
> 
> Cc: linux-kernel@vger.kernel.org
> Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
> Cc: Ram Pai <linuxram@us.ibm.com>
> Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
> Cc: Laurent Dufour <ldufour@linux.ibm.com>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>

Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>

> Signed-off-by: Satheesh Rajendran <sathnaga@linux.vnet.ibm.com>
> ---
> 
> V2:
> Added reviewed by Thiago.
> Dropped align argument as per Michael suggest.
> Modified commit msg.
> 
> V1: http://patchwork.ozlabs.org/project/linuxppc-dev/patch/20200609113909.17236-1-sathnaga@linux.vnet.ibm.com/
> ---
>   arch/powerpc/kernel/paca.c | 12 +++++++++---
>   1 file changed, 9 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/kernel/paca.c b/arch/powerpc/kernel/paca.c
> index 8d96169c597e..a174d64d9b4d 100644
> --- a/arch/powerpc/kernel/paca.c
> +++ b/arch/powerpc/kernel/paca.c
> @@ -57,8 +57,8 @@ static void *__init alloc_paca_data(unsigned long size, unsigned long align,
>   
>   #define LPPACA_SIZE 0x400
>   
> -static void *__init alloc_shared_lppaca(unsigned long size, unsigned long align,
> -					unsigned long limit, int cpu)
> +static void *__init alloc_shared_lppaca(unsigned long size, unsigned long limit,
> +					int cpu)
>   {
>   	size_t shared_lppaca_total_size = PAGE_ALIGN(nr_cpu_ids * LPPACA_SIZE);
>   	static unsigned long shared_lppaca_size;
> @@ -68,6 +68,12 @@ static void *__init alloc_shared_lppaca(unsigned long size, unsigned long align,
>   	if (!shared_lppaca) {
>   		memblock_set_bottom_up(true);
>   
> +		/* See Documentation/powerpc/ultravisor.rst for mode details
> +		 *
> +		 * UV/HV data share is in PAGE granularity, In order to
> +		 * minimize the number of pages shared and maximize the
> +		 * use of a page, let's use page align.
> +		 */
>   		shared_lppaca =
>   			memblock_alloc_try_nid(shared_lppaca_total_size,
>   					       PAGE_SIZE, MEMBLOCK_LOW_LIMIT,
> @@ -122,7 +128,7 @@ static struct lppaca * __init new_lppaca(int cpu, unsigned long limit)
>   		return NULL;
>   
>   	if (is_secure_guest())
> -		lp = alloc_shared_lppaca(LPPACA_SIZE, 0x400, limit, cpu);
> +		lp = alloc_shared_lppaca(LPPACA_SIZE, limit, cpu);
>   	else
>   		lp = alloc_paca_data(LPPACA_SIZE, 0x400, limit, cpu);
>   
> 

Re: [PATCH V2] powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() function

[Michael Ellerman]

On Fri, 12 Jun 2020 19:59:53 +0530, Satheesh Rajendran wrote:
> Argument "align" in alloc_shared_lppaca() was unused inside the
> function. Let's drop it and update code comment for page alignment.

Applied to powerpc/next.

[1/1] powerpc/pseries/svm: Drop unused align argument in alloc_shared_lppaca() function
      https://git.kernel.org/powerpc/c/178748b6d14946f080d49bc7dcc47b7cc4437e4d

cheers