meson: improve CPU affinity routines check

Recently, FreeBSD has got sched_get/setaffinity(3) implementations and
the sched.h header as well [1]. To make these routines visible,
users have to define _WITH_CPU_SET_T.

This breaks current detection. Specifically, meson sees the
sched_getaffinity() symbol and defines WITH_SCHED_GETAFFINITY. This
define unlocks Linux implementation of virProcessSetAffinity() and other
functions, which fails to build on FreeBSD because cpu_set_t is not
visible as _WITH_CPU_SET_T is not defined.

For now, change detection to the following:

 - Instead of checking sched_getaffinity(), check if 'cpu_set_t' is
   available through sched.h
 - Explicitly check the sched.h header instead of assuming its presence
   if WITH_SCHED_SETSCHEDULER is defined

1:
https://cgit.freebsd.org/src/commit/?id=43736b71dd051212d5c55be9fa21c45993017fbb
https://cgit.freebsd.org/src/commit/?id=160b4b922b6021848b6b48afc894d16b879b7af2
https://cgit.freebsd.org/src/commit/?id=90fa9705d5cd29cf11c5dc7319299788dec2546a

Signed-off-by: Roman Bogorodskiy <bogorodskiy@gmail.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>

diff --git a/meson.build b/meson.build
index 9022bcfdc9513726106a812d77441f369338c2a2..e4f36e857449e372cd9e8630c47744b6bb35c70a 100644 (file)
--- a/meson.build
+++ b/meson.build
@@ -553,7 +553,6 @@ functions = [
   'posix_fallocate',
   'posix_memalign',
   'prlimit',
-  'sched_getaffinity',
   'sched_setscheduler',
   'setgroups',
   'setns',
@@ -602,6 +601,7 @@ headers = [
   'net/if.h',
   'pty.h',
   'pwd.h',
+  'sched.h',
   'sys/auxv.h',
   'sys/ioctl.h',
   'sys/mount.h',
@@ -671,6 +671,8 @@ symbols = [
 
   # Check for BSD approach for setting MAC addr
   [ 'net/if_dl.h', 'link_addr', '#include <sys/types.h>\n#include <sys/socket.h>' ],
+
+  [ 'sched.h', 'cpu_set_t' ],
 ]
 
 if host_machine.system() == 'linux'

diff --git a/src/util/virprocess.c b/src/util/virprocess.c
index 6de3f36f529cee44b2891beb194b5ada980925c5..81de90200e7cfa982f303391d576e20de9ac91f0 100644 (file)
--- a/src/util/virprocess.c
+++ b/src/util/virprocess.c
@@ -35,7 +35,7 @@
 # include <sys/time.h>
 # include <sys/resource.h>
 #endif
-#if WITH_SCHED_SETSCHEDULER
+#if WITH_SCHED_H
 # include <sched.h>
 #endif
 
@@ -480,7 +480,7 @@ int virProcessKillPainfully(pid_t pid, bool force)
     return virProcessKillPainfullyDelay(pid, force, 0, false);
 }
 
-#if WITH_SCHED_GETAFFINITY
+#if WITH_DECL_CPU_SET_T
 
 int virProcessSetAffinity(pid_t pid, virBitmap *map, bool quiet)
 {
@@ -626,7 +626,7 @@ virProcessGetAffinity(pid_t pid)
     return ret;
 }
 
-#else /* WITH_SCHED_GETAFFINITY */
+#else /* WITH_DECL_CPU_SET_T */
 
 int virProcessSetAffinity(pid_t pid G_GNUC_UNUSED,
                           virBitmap *map G_GNUC_UNUSED,
@@ -646,7 +646,7 @@ virProcessGetAffinity(pid_t pid G_GNUC_UNUSED)
                          _("Process CPU affinity is not supported on this platform"));
     return NULL;
 }
-#endif /* WITH_SCHED_GETAFFINITY */
+#endif /* WITH_DECL_CPU_SET_T */
 
 
 int virProcessGetPids(pid_t pid, size_t *npids, pid_t **pids)