Re: [PATCH v2] perf tools: Work around lack of sched_getcpu in glibc < 2.6.

From: Jiri Olsa
Date: Thu Mar 19 2015 - 06:13:17 EST


On Wed, Mar 18, 2015 at 04:11:52PM -0700, Vinson Lee wrote:
> From: Vinson Lee <vlee@xxxxxxxxxxx>
>
> This patch fixes this build error with glibc < 2.6.
>
> CC util/cloexec.o
> cc1: warnings being treated as errors
> util/cloexec.c: In function âperf_flag_probeâ:
> util/cloexec.c:24: error: implicit declaration of function
> âsched_getcpuâ
> util/cloexec.c:24: error: nested extern declaration of âsched_getcpuâ
> make: *** [util/cloexec.o] Error 1
>
> Cc: stable@xxxxxxxxxxxxxxx # 3.18+
> Signed-off-by: Vinson Lee <vlee@xxxxxxxxxxx>
> ---
> tools/perf/util/cloexec.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/tools/perf/util/cloexec.c b/tools/perf/util/cloexec.c
> index 6da965b..285bd70 100644
> --- a/tools/perf/util/cloexec.c
> +++ b/tools/perf/util/cloexec.c
> @@ -7,6 +7,16 @@
>
> static unsigned long flag = PERF_FLAG_FD_CLOEXEC;
>
> +#ifdef __GLIBC_PREREQ
> +#if !__GLIBC_PREREQ(2, 6)
> +static int sched_getcpu(void)
> +{
> + errno = ENOSYS;
> + return -1;
> +}
> +#endif
> +#endif

you could mark it as __weak and get rid of those ifdef's
like we do for strlcpy in utilpath.c

jirka
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/