X-Git-Url: https://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=urcu-bp.c;h=14b200129fe42656ae11e178aa0d3c6442f26061;hp=62d270412823062ac175aaeb4f412b1518c34c8f;hb=f7a3d9d917966b0acb45399a66d42dd7e7acb0ca;hpb=6cf3827cf5809fbcee555fb08286ad756be42dad

diff --git a/urcu-bp.c b/urcu-bp.c
index 62d2704..14b2001 100644
--- a/urcu-bp.c
+++ b/urcu-bp.c
@@ -35,6 +35,8 @@
 #include <unistd.h>
 #include <sys/mman.h>
 
+#include "urcu-bp-map.h"
+
 #include "urcu-bp-static.h"
 /* Do not #define _LGPL_SOURCE to ensure we can emit the wrapper symbols */
 #include "urcu-bp.h"
@@ -76,6 +78,9 @@ struct registry_arena {
 
 static struct registry_arena registry_arena;
 
+/* Saved fork signal mask, protected by rcu_gp_lock */
+static sigset_t saved_fork_signal_mask;
+
 static void rcu_gc_registry(void);
 
 static void mutex_lock(pthread_mutex_t *mutex)
@@ -95,11 +100,6 @@ static void mutex_lock(pthread_mutex_t *mutex)
 			perror("Error in pthread mutex lock");
 			exit(-1);
 		}
-		if (rcu_reader.need_mb) {
-			cmm_smp_mb();
-			rcu_reader.need_mb = 0;
-			cmm_smp_mb();
-		}
 		poll(NULL,0,10);
 	}
 #endif /* #else #ifndef DISTRUST_SIGNALS_EXTREME */
@@ -336,3 +336,47 @@ void rcu_bp_exit()
 {
 	munmap(registry_arena.p, registry_arena.len);
 }
+
+/*
+ * Holding the rcu_gp_lock across fork will make sure we fork() don't race with
+ * a concurrent thread executing with this same lock held. This ensures that the
+ * registry is in a coherent state in the child.
+ */
+void rcu_bp_before_fork(void)
+{
+	sigset_t newmask, oldmask;
+	int ret;
+
+	ret = sigemptyset(&newmask);
+	assert(!ret);
+	ret = pthread_sigmask(SIG_SETMASK, &newmask, &oldmask);
+	assert(!ret);
+	mutex_lock(&rcu_gp_lock);
+	saved_fork_signal_mask = oldmask;
+}
+
+void rcu_bp_after_fork_parent(void)
+{
+	sigset_t oldmask;
+	int ret;
+
+	oldmask = saved_fork_signal_mask;
+	mutex_unlock(&rcu_gp_lock);
+	ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
+	assert(!ret);
+}
+
+void rcu_bp_after_fork_child(void)
+{
+	sigset_t oldmask;
+	int ret;
+
+	rcu_gc_registry();
+	oldmask = saved_fork_signal_mask;
+	mutex_unlock(&rcu_gp_lock);
+	ret = pthread_sigmask(SIG_SETMASK, &oldmask, NULL);
+	assert(!ret);
+}
+
+#include "urcu-call-rcu-impl.h"
+#include "urcu-defer-impl.h"