[pulseaudio-commits] src/pulsecore

[Tanu Kaskinen]

 src/pulsecore/core-util.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

New commits:
commit 1df21e6ab6cd42e2f7601a6c5577c20b7e3d1046
Author: John Paul Adrian Glaubitz <glaubitz at physik.fu-berlin.de>
Date:   Mon Jul 4 20:23:17 2016 +0200

    core-util: Use _SC_NPROCESSORS_ONLN instead of _SC_NPROCESSORS_CONF
    
    pa_ncpu() is supposed to report the number of processors available on
    the system. For that, it currently calls sysconf(_SC_NPROCESSORS_CONF).
    However, since the operating system can disable individual processors,
    we should call sysconf(_SC_NPROCESSORS_ONLN) to determine the number
    of processors currently available [1]. Consequently, the once-test will
    fail since pthread_setaffinity_np() is called with CPUs that are
    currently not available.
    
    It might also be advisable to change the code in the future to use CPU
    sets on Linux as even the suggested change is not 100% safe but at least
    it improves over the existing code. If PulseAudio was to be run in a CPU
    set [2], the number of processors available to PulseAudio could be even
    less than the number of CPUs currently online (_SC_NPROCESSORS_CONF).
    
    [1] https://www.gnu.org/software/libc/manual/html_node/Processor-Resources.html
    [2] http://man7.org/linux/man-pages/man7/cpuset.7.html
    
    BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=96809
    Signed-off-by: John Paul Adrian Glaubitz <glaubitz at physik.fu-berlin.de>

diff --git a/src/pulsecore/core-util.c b/src/pulsecore/core-util.c
index f816da9..f648af8 100644
--- a/src/pulsecore/core-util.c
+++ b/src/pulsecore/core-util.c
@@ -3179,8 +3179,8 @@ void pa_reduce(unsigned *num, unsigned *den) {
 unsigned pa_ncpus(void) {
     long ncpus;
 
-#ifdef _SC_NPROCESSORS_CONF
-    ncpus = sysconf(_SC_NPROCESSORS_CONF);
+#ifdef _SC_NPROCESSORS_ONLN
+    ncpus = sysconf(_SC_NPROCESSORS_ONLN);
 #else
     ncpus = 1;
 #endif