Re: [PATCH v3] powerpc: Fix static-linked version of __ppc_get_timebase_freq [BZ #24640]

[Tulio Magno Quites Machado Filho <tuliom at ascii dot art dot br>]

Raoni Fassina Firmino <raoni@linux.ibm.com> writes:

> __ppc_get_timebase_freq() always return 0 when using static linked
> glibc.
>
> This is a minimal example.c to reproduce:
>
>     /******************************/
>     #include <inttypes.h>
>     #include <stdint.h>
>     #include <stdio.h>
>     #include <sys/platform/ppc.h>
>
>     int main() {
>         uint64_t freq = __ppc_get_timebase_freq();
>         printf("Time Base frequency = %"PRIu64" Hz\n", freq);
>         if (freq == 0)
>             return -1;
>         return 0;
>     }
>     /******************************/
>
> Compile command: gcc -static example.c
>
> This bug has been reproduced, fixed and tested on all powerpc platforms
> (ppc32, ppc64 and ppc64le).
>
> The underlying code of __ppc_get_timebase_freq uses __get_timebase_freq
> that has a different implementation for shared and static version of
> glibc.  In the static version, there is an incorrect sense in the if
> check for the fd returned when opening /proc/cpuinfo.
>
> This solution is mostly a cherry-pick from:
>
>   commit 4791e4f773d060c1a37b27aac5b03cdfa9327afc
>   Author: Stan Shebs <stanshebs@google.com>
>   Date:   Fri May 17 12:25:19 2019 -0700
>   Subject: Fix sense of a test in the static-linking version of ppc get_clockfreq
>
> That is in branch glibc/google/grte/v5-2.27/master and was mentioned for
> inclusion on master here:
>
>   https://www.sourceware.org/ml/libc-alpha/2019-05/msg00409.html
>
> Adapted from original fix for get_clockfreq. That code was moved to
> get_timebase_freq.
>
> Also added a static-build testcase for __ppc_get_timebase_freq since the
> underlying function has different implementations for shared and static
> build.

LGTM too.

Pushed as 335c1007bf18.

Thanks!!

-- 
Tulio Magno