re PR other/58996 (build failure in libcilkrts)

Fix for PR other/58996.
+2014-01-20  Balaji V. Iyer  <balaji.v.iyer@intel.com>
+
+       PR other/58996
+       * configure.ac: Added a check for pthread affinity support.
+       * runtime/os-unix.c: Likewise.
+       * configure: Regenerate.
+

From-SVN: r206846

libcilkrts/ChangeLog

@@ -1,3 +1,10 @@
+2014-01-20  Balaji V. Iyer  <balaji.v.iyer@intel.com>
+
+	PR other/58996
+	* configure.ac: Added a check for pthread affinity support.
+	* runtime/os-unix.c: Likewise.
+	* configure: Regenerate.
+
 2014-01-09  Balaji V. Iyer  <balaji.v.iyer@intel.com>
 
 	bootstrap/59094

libcilkrts/configure

@@ -14420,6 +14420,38 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
+# Check for pthread_{,attr_}[sg]etaffinity_np.
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+#define _GNU_SOURCE
+   #include <pthread.h>
+int
+main ()
+{
+cpu_set_t cpuset;
+   pthread_attr_t attr;
+   pthread_getaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
+   if (CPU_ISSET (0, &cpuset))
+     CPU_SET (1, &cpuset);
+   else
+     CPU_ZERO (&cpuset);
+   pthread_setaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
+   pthread_attr_init (&attr);
+   pthread_attr_getaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);
+   pthread_attr_setaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+
+$as_echo "#define HAVE_PTHREAD_AFFINITY_NP 1" >>confdefs.h
+
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+
+
 # Must be last
 cat >confcache <<\_ACEOF
 # This file is a shell script that caches the results of configure

libcilkrts/configure.ac

@@ -164,5 +164,25 @@ AC_SUBST(toolexeclibdir)
 
 AC_SUBST(lt_cv_dlopen_libs)
 
+# Check for pthread_{,attr_}[sg]etaffinity_np.
+AC_LINK_IFELSE(
+ [AC_LANG_PROGRAM(
+  [#define _GNU_SOURCE
+   #include <pthread.h>],
+  [cpu_set_t cpuset;
+   pthread_attr_t attr;
+   pthread_getaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
+   if (CPU_ISSET (0, &cpuset))
+     CPU_SET (1, &cpuset);
+   else
+     CPU_ZERO (&cpuset);
+   pthread_setaffinity_np (pthread_self (), sizeof (cpu_set_t), &cpuset);
+   pthread_attr_init (&attr);
+   pthread_attr_getaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);
+   pthread_attr_setaffinity_np (&attr, sizeof (cpu_set_t), &cpuset);])],
+  AC_DEFINE(HAVE_PTHREAD_AFFINITY_NP, 1,
+[       Define if pthread_{,attr_}{g,s}etaffinity_np is supported.]))
+
+
 # Must be last
 AC_OUTPUT

libcilkrts/runtime/os-unix.c

@@ -311,6 +311,10 @@ static pid_t linux_gettid(void)
  */
 static int linux_get_affinity_count (int tid) 
 {
+#if !defined HAVE_PTHREAD_AFFINITY_NP
+  return 0;
+#else
+
     cpu_set_t process_mask;
 
     // Extract the thread affinity mask
@@ -337,6 +341,7 @@ static int linux_get_affinity_count (int tid)
     }
 
     return available_procs;
+#endif
 }
 #endif