[glibc/zack/no-nested-includes] powerpc: Fix static-linked version of __ppc_get_timebase_freq [BZ #24640]

[Zack Weinberg <zack at sourceware dot org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=335c1007bf183163c0a19724111a64097955b325

commit 335c1007bf183163c0a19724111a64097955b325
Author: Stan Shebs <stanshebs@google.com>
Date:   Wed Jun 19 17:15:35 2019 -0300

    powerpc: Fix static-linked version of __ppc_get_timebase_freq [BZ #24640]
    
    __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.
    
    	[BZ #24640]
    	* sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
    	[!SHARED] (__get_timebase_freq): Fix sense of a test in the
    	static-linking version.
    	* sysdeps/unix/sysv/linux/powerpc/Makefile
    	(tests-static): Add test-gettimebasefreq-static.
    	(tests): Likewise.
    	* sysdeps/unix/sysv/linux/powerpc/test-gettimebasefreq-static.c:
    	New file.

Diff:
---
 ChangeLog                                             | 13 +++++++++++++
 sysdeps/unix/sysv/linux/powerpc/Makefile              |  2 ++
 sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c   |  2 +-
 .../sysv/linux/powerpc/test-gettimebasefreq-static.c  | 19 +++++++++++++++++++
 4 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index 729301f..5438ff1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2019-06-19  Stan Shebs  <stanshebs@google.com>
+	    Raoni Fassina Firmino  <raoni@linux.ibm.com>
+
+	[BZ #24640]
+	* sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
+	[!SHARED] (__get_timebase_freq): Fix sense of a test in the
+	static-linking version.
+	* sysdeps/unix/sysv/linux/powerpc/Makefile
+	(tests-static): Add test-gettimebasefreq-static.
+	(tests): Likewise.
+	* sysdeps/unix/sysv/linux/powerpc/test-gettimebasefreq-static.c:
+	New file.
+
 2019-06-19  Rafal Luzynski  <digitalfreak@lingonborough.com>
 
 	[BZ #24614]
diff --git a/sysdeps/unix/sysv/linux/powerpc/Makefile b/sysdeps/unix/sysv/linux/powerpc/Makefile
index 19ac59d..1596238 100644
--- a/sysdeps/unix/sysv/linux/powerpc/Makefile
+++ b/sysdeps/unix/sysv/linux/powerpc/Makefile
@@ -25,6 +25,8 @@ endif
 ifeq ($(subdir),misc)
 sysdep_headers += bits/ppc.h
 sysdep_routines += get_timebase_freq
+tests-static += test-gettimebasefreq-static
+tests += $(tests-static)
 tests += test-gettimebasefreq
 tests += test-powerpc-linux-sysconf
 endif
diff --git a/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c b/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
index 23e7694..c245e97 100644
--- a/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
+++ b/sysdeps/unix/sysv/linux/powerpc/get_timebase_freq.c
@@ -39,7 +39,7 @@ __get_timebase_freq (void)
      timebase        : 33333333
      We search for this line and convert the number into an integer.  */
   int fd = __open_nocancel ("/proc/cpuinfo", O_RDONLY);
-  if (__glibc_likely (fd != -1))
+  if (__glibc_unlikely (fd == -1))
     return result;
 
   /* The timebase will be in the 1st 1024 bytes for systems with up
diff --git a/sysdeps/unix/sysv/linux/powerpc/test-gettimebasefreq-static.c b/sysdeps/unix/sysv/linux/powerpc/test-gettimebasefreq-static.c
new file mode 100644
index 0000000..58b4eee
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/powerpc/test-gettimebasefreq-static.c
@@ -0,0 +1,19 @@
+/* Check __ppc_get_timebase_freq() for architecture changes
+   Copyright (C) 2019 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "test-gettimebasefreq.c"