[PATCH] arm64: mm: use macro instead of if judgement of ZONE_DMA

[PATCH] arm64: mm: use macro instead of if judgement of ZONE_DMA

[Yifan Zhang]

if disable CONFIG_ZONE_DMA, ZONE_DMA becomes undefined.



Signed-off-by: Yifan Zhang <zhangyf@marvell.com>

---

 arch/arm64/mm/init.c |   12 +++++++-----

 1 file changed, 7 insertions(+), 5 deletions(-)



diff --git a/arch/arm64/mm/init.c b/arch/arm64/mm/init.c index
494297c..887ca5d 100644

--- a/arch/arm64/mm/init.c

+++ b/arch/arm64/mm/init.c

@@ -82,10 +82,10 @@ static void __init zone_sizes_init(unsigned long
min, unsigned long max)

        memset(zone_size, 0, sizeof(zone_size));



        /* 4GB maximum for 32-bit only capable devices */

-        if (IS_ENABLED(CONFIG_ZONE_DMA)) {

-                 max_dma = PFN_DOWN(max_zone_dma_phys());

-                 zone_size[ZONE_DMA] = max_dma - min;

-        }

+#ifdef CONFIG_ZONE_DMA

+       max_dma = PFN_DOWN(max_zone_dma_phys());

+       zone_size[ZONE_DMA] = max_dma - min;

+#endif

        zone_size[ZONE_NORMAL] = max - max_dma;



       memcpy(zhole_size, zone_size, sizeof(zhole_size)); @@ -97,10
+97,12 @@ static void __init zone_sizes_init(unsigned long min,
unsigned long max)

                 if (start >= max)

                           continue;



-                 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {

+#ifdef CONFIG_ZONE_DMA

+                if (start < max_dma) {

                           unsigned long dma_end = min(end, max_dma);

                           zhole_size[ZONE_DMA] -= dma_end - start;

                 }

+#endif



                 if (end > max_dma) {

                           unsigned long normal_end = min(end, max);

--

1.7.9.5

[PATCH] arm64: mm: use macro instead of if judgement of ZONE_DMA

[Uwe Kleine-König]

Hello,

On Thu, Oct 16, 2014 at 05:19:43PM +0800, Yifan Zhang wrote:
> @@ -82,10 +82,10 @@ static void __init zone_sizes_init(unsigned long
> min, unsigned long max)
> 
>         memset(zone_size, 0, sizeof(zone_size));
> 
> 
> 
>         /* 4GB maximum for 32-bit only capable devices */
> 
> -        if (IS_ENABLED(CONFIG_ZONE_DMA)) {
> 
> -                 max_dma = PFN_DOWN(max_zone_dma_phys());
> 
> -                 zone_size[ZONE_DMA] = max_dma - min;
> 
> -        }
> 
> +#ifdef CONFIG_ZONE_DMA
> 
> +       max_dma = PFN_DOWN(max_zone_dma_phys());
> 
> +       zone_size[ZONE_DMA] = max_dma - min;
> 
> +#endif
Apart from your patch being broken (probably by your MUA or MTA) usually
if (IS_ENABLED(...)) is preferred over #ifdef because it doesn't stand
out over the other program source.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-K?nig            |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

[PATCH] arm64: mm: use macro instead of if judgement of ZONE_DMA

[Yifan Zhang]

Hi Uwe,

Yes, the first patch is broken. So I sent a v2 which is in correct format.

I understand IS_ENABLED is better, but in this case, we can't use "if"
since "ZONE_DMA" is defined under "#ifdef CONFIG_ZONE_DMA". In current
code, once we disable CONFIG_ZONE_DMA, "zone_size[ZONE_DMA]" will
report compiling error as below:


# configuration written to .config
#
making android
scripts/kconfig/conf --silentoldconfig Kconfig
  CHK     include/generated/uapi/linux/version.h
  CHK     include/generated/utsrelease.h
  CALL    scripts/checksyscalls.sh
  CC      scripts/mod/devicetable-offsets.s
  GEN     scripts/mod/devicetable-offsets.h
  HOSTCC  scripts/mod/file2alias.o
  HOSTLD  scripts/mod/modpost
  CHK     include/generated/compile.h
  CC      arch/arm64/mm/init.o
make[1]: Nothing to be done for `dtbs'.
  CGIT    kernel/gitinfo.S
arch/arm64/mm/init.c: In function 'zone_sizes_init':
arch/arm64/mm/init.c:85:13: error: 'ZONE_DMA' undeclared (first use in
this function)
   zone_size[ZONE_DMA] = max_dma - min;
             ^
arch/arm64/mm/init.c:85:13: note: each undeclared identifier is
reported only once for each function it appears in
make[1]: *** [arch/arm64/mm/init.o] Error 1
make: *** [arch/arm64/mm] Error 2
make: *** Waiting for unfinished jobs....
  AS      kernel/gitinfo.o
  LD      kernel/built-in.o


BR,
Yifan

On Fri, Oct 17, 2014 at 6:51 PM, Uwe Kleine-K?nig
<u.kleine-koenig@pengutronix.de> wrote:
> Hello,
>
> On Thu, Oct 16, 2014 at 05:19:43PM +0800, Yifan Zhang wrote:
>> @@ -82,10 +82,10 @@ static void __init zone_sizes_init(unsigned long
>> min, unsigned long max)
>>
>>         memset(zone_size, 0, sizeof(zone_size));
>>
>>
>>
>>         /* 4GB maximum for 32-bit only capable devices */
>>
>> -        if (IS_ENABLED(CONFIG_ZONE_DMA)) {
>>
>> -                 max_dma = PFN_DOWN(max_zone_dma_phys());
>>
>> -                 zone_size[ZONE_DMA] = max_dma - min;
>>
>> -        }
>>
>> +#ifdef CONFIG_ZONE_DMA
>>
>> +       max_dma = PFN_DOWN(max_zone_dma_phys());
>>
>> +       zone_size[ZONE_DMA] = max_dma - min;
>>
>> +#endif
> Apart from your patch being broken (probably by your MUA or MTA) usually
> if (IS_ENABLED(...)) is preferred over #ifdef because it doesn't stand
> out over the other program source.
>
> Best regards
> Uwe
>
> --
> Pengutronix e.K.                           | Uwe Kleine-K?nig            |
> Industrial Linux Solutions                 | http://www.pengutronix.de/  |