X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu.c;h=69ebcaa9cb0fbfa07a264ab94fa5261513c72424;hp=b3f94da9a2b733e30c08eb014c095933e2e13561;hb=9ba261bd496f2dfac38a16e341259553335dd165;hpb=4de0cd31491bcb93a19c14fc1eb2a2a23ce12855

diff --git a/urcu.c b/urcu.c
index b3f94da..69ebcaa 100644
--- a/urcu.c
+++ b/urcu.c
@@ -62,6 +62,24 @@
  */
 #define RCU_QS_ACTIVE_ATTEMPTS 100
 
+/*
+ * RCU_MEMBARRIER is only possibly available on Linux.
+ */
+#if defined(RCU_MEMBARRIER) && defined(__linux__)
+#include <urcu/syscall-compat.h>
+#endif
+
+/* If the headers do not support SYS_membarrier, fall back on RCU_MB */
+#ifdef SYS_membarrier
+# define membarrier(...)		syscall(SYS_membarrier, __VA_ARGS__)
+#else
+# define membarrier(...)		-ENOSYS
+#endif
+
+#define MEMBARRIER_EXPEDITED		(1 << 0)
+#define MEMBARRIER_DELAYED		(1 << 1)
+#define MEMBARRIER_QUERY		(1 << 16)
+
 #ifdef RCU_MEMBARRIER
 static int init_done;
 int rcu_has_sys_membarrier;
@@ -139,7 +157,7 @@ static void mutex_unlock(pthread_mutex_t *mutex)
 static void smp_mb_master(int group)
 {
 	if (caa_likely(rcu_has_sys_membarrier))
-		membarrier(MEMBARRIER_EXPEDITED);
+		(void) membarrier(MEMBARRIER_EXPEDITED);
 	else
 		cmm_smp_mb();
 }
@@ -495,14 +513,14 @@ void rcu_init(void)
 
 void rcu_exit(void)
 {
-	struct sigaction act;
-	int ret;
-
-	ret = sigaction(SIGRCU, NULL, &act);
-	if (ret)
-		urcu_die(errno);
-	assert(act.sa_sigaction == sigrcu_handler);
-	assert(cds_list_empty(&registry));
+	/*
+	 * Don't unregister the SIGRCU signal handler anymore, because
+	 * call_rcu threads could still be using it shortly before the
+	 * application exits.
+	 * Assertion disabled because call_rcu threads are now rcu
+	 * readers, and left running at exit.
+	 * assert(cds_list_empty(&registry));
+	 */
 }
 
 #endif /* #ifdef RCU_SIGNAL */