Re: [PATCH] tools/perf/arch/powerpc/util: Fix is_compat_mode build break in ppc64

[Venkat Rao Bagalkote <venkat88@linux.ibm.com>]

On 21/03/25 3:37 pm, Likhitha Korrapati wrote:
> Commit 54f9aa1092457 ("tools/perf/powerpc/util: Add support to
> handle compatible mode PVR for perf json events") introduced
> to select proper JSON events in case of compat mode using
> auxiliary vector. But this caused a compilation error in ppc64
> Big Endian.
>
> arch/powerpc/util/header.c: In function 'is_compat_mode':
> arch/powerpc/util/header.c:20:21: error: cast to pointer from
> integer of different size [-Werror=int-to-pointer-cast]
>     20 |         if (!strcmp((char *)platform, (char *)base_platform))
>        |                     ^
> arch/powerpc/util/header.c:20:39: error: cast to pointer from
> integer of different size [-Werror=int-to-pointer-cast]
>     20 |         if (!strcmp((char *)platform, (char *)base_platform))
>        |
>
> Commit saved the getauxval(AT_BASE_PLATFORM) and getauxval(AT_PLATFORM)
> return values in u64 which causes the compilation error.
>
> Patch fixes this issue by changing u64 to "unsigned long".
>
> Fixes: 54f9aa1092457 ("tools/perf/powerpc/util: Add support to handle compatible mode PVR for perf json events")
> Signed-off-by: Likhitha Korrapati <likhitha@linux.ibm.com>
> ---
>   tools/perf/arch/powerpc/util/header.c | 4 ++--
>   1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/tools/perf/arch/powerpc/util/header.c b/tools/perf/arch/powerpc/util/header.c
> index c7df534dbf8f..0be74f048f96 100644
> --- a/tools/perf/arch/powerpc/util/header.c
> +++ b/tools/perf/arch/powerpc/util/header.c
> @@ -14,8 +14,8 @@
>   
>   static bool is_compat_mode(void)
>   {
> -	u64 base_platform = getauxval(AT_BASE_PLATFORM);
> -	u64 platform = getauxval(AT_PLATFORM);
> +	unsigned long base_platform = getauxval(AT_BASE_PLATFORM);
> +	unsigned long platform = getauxval(AT_PLATFORM);
>   
>   	if (!strcmp((char *)platform, (char *)base_platform))
>   		return false;

Applied this patch on the powerpc kernel and it fixes the issue.


Without this patch:

   INSTALL libsubcmd_headers
   INSTALL libsymbol_headers
   INSTALL libperf_headers
   INSTALL libapi_headers
   CC      /output/arch/powerpc/util/header.o
   CC      /output/arch/powerpc/util/perf_regs.o
   CC      /output/arch/powerpc/util/mem-events.o
   CC      /output/arch/powerpc/util/pmu.o
   CC      /output/arch/powerpc/util/sym-handling.o
   CC      /output/arch/powerpc/util/evsel.o
   CC      /output/arch/powerpc/util/event.o
arch/powerpc/util/header.c: In function 'is_compat_mode':
arch/powerpc/util/header.c:20:21: error: cast to pointer from integer of 
different size [-Werror=int-to-pointer-cast]
    20 |         if (!strcmp((char *)platform, (char *)base_platform))
       |                     ^
arch/powerpc/util/header.c:20:39: error: cast to pointer from integer of 
different size [-Werror=int-to-pointer-cast]
    20 |         if (!strcmp((char *)platform, (char *)base_platform))
       |                                       ^
cc1: all warnings being treated as errors
make[6]: *** [/linux/tools/build/Makefile.build:85: 
/output/arch/powerpc/util/header.o] Error 1
make[6]: *** Waiting for unfinished jobs....
make[5]: *** [/linux/tools/build/Makefile.build:138: util] Error 2
make[4]: *** [/linux/tools/build/Makefile.build:138: powerpc] Error 2
make[3]: *** [/linux/tools/build/Makefile.build:138: arch] Error 2
make[3]: *** Waiting for unfinished jobs....
make[2]: *** [Makefile.perf:781: /output/perf-util-in.o] Error 2
make[1]: *** [Makefile.perf:280: sub-make] Error 2
make: *** [Makefile:76: all] Error 2
make: Leaving directory '/linux/tools/perf'


With this patch:

   PERF_VERSION = 6.14.rc4.gbdfd7b9150f1
   INSTALL libapi_headers
   GEN     perf-archive
   GEN     perf-iostat
   INSTALL libperf_headers
   CC      /output/arch/powerpc/util/header.o
   LD      /output/arch/powerpc/util/perf-util-in.o
   LD      /output/arch/powerpc/perf-util-in.o
   LD      /output/arch/perf-util-in.o
   CC      /output/util/header.o
   LD      /output/util/perf-util-in.o
   LD      /output/perf-util-in.o
   AR      /output/libperf-util.a
   LINK    /output/perf
make: Leaving directory '/linux/tools/perf'
## tools/perf build completed rc = 0
## Build completed OK


Please add below tag:

Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>


Regards,

Venkat.