X-Git-Url: https://git.lttng.org/?a=blobdiff_plain;f=urcu-static.h;h=1eeb2e6b03319c313d051ef71a3148add48ff264;hb=b95a001f50047ab146becf9b9e514ab0639f67cd;hp=e1d0704d1af54cad91ca5c0295f00d92a9cabece;hpb=cf5271eed768bea133b1916eca1d1917920e3105;p=urcu.git

diff --git a/urcu-static.h b/urcu-static.h
index e1d0704..1eeb2e6 100644
--- a/urcu-static.h
+++ b/urcu-static.h
@@ -77,7 +77,12 @@ extern "C" {
 /*
  * The signal number used by the RCU library can be overridden with
  * -DSIGRCU= when compiling the library.
+ * Provide backward compatibility for liburcu 0.3.x SIGURCU.
  */
+#ifdef SIGURCU
+#define SIGRCU SIGURCU
+#endif
+
 #ifndef SIGRCU
 #define SIGRCU SIGUSR1
 #endif
@@ -155,10 +160,25 @@ static inline void debug_yield_init(void)
 }
 #endif
 
+/*
+ * RCU memory barrier broadcast group. Currently, only broadcast to all process
+ * threads is supported (group 0).
+ *
+ * Slave barriers are only guaranteed to be ordered wrt master barriers.
+ *
+ * The pair ordering is detailed as (O: ordered, X: not ordered) :
+ *               slave  master
+ *        slave    X      O
+ *        master   O      O
+ */
+
+#define MB_GROUP_ALL		0
+#define RCU_MB_GROUP		MB_GROUP_ALL
+
 #ifdef RCU_MEMBARRIER
 extern int has_sys_membarrier;
 
-static inline void smp_mb_light()
+static inline void smp_mb_slave(int group)
 {
 	if (likely(has_sys_membarrier))
 		barrier();
@@ -168,14 +188,14 @@ static inline void smp_mb_light()
 #endif
 
 #ifdef RCU_MB
-static inline void smp_mb_light()
+static inline void smp_mb_slave(int group)
 {
 	smp_mb();
 }
 #endif
 
 #ifdef RCU_SIGNAL
-static inline void smp_mb_light()
+static inline void smp_mb_slave(int group)
 {
 	barrier();
 }
@@ -187,7 +207,7 @@ static inline void smp_mb_light()
  */
 #define RCU_GP_COUNT		(1UL << 0)
 /* Use the amount of bits equal to half of the architecture long size */
-#define RCU_GP_CTR_PHASE	(1UL << (sizeof(long) << 2))
+#define RCU_GP_CTR_PHASE	(1UL << (sizeof(unsigned long) << 2))
 #define RCU_GP_CTR_NEST_MASK	(RCU_GP_CTR_PHASE - 1)
 
 /*
@@ -195,11 +215,11 @@ static inline void smp_mb_light()
  * Using a int rather than a char to eliminate false register dependencies
  * causing stalls on some architectures.
  */
-extern long rcu_gp_ctr;
+extern unsigned long rcu_gp_ctr;
 
 struct rcu_reader {
 	/* Data used by both reader and synchronize_rcu() */
-	long ctr;
+	unsigned long ctr;
 	char need_mb;
 	/* Data used for registry */
 	struct list_head head __attribute__((aligned(CACHE_LINE_SIZE)));
@@ -222,9 +242,9 @@ static inline void wake_up_gp(void)
 	}
 }
 
-static inline int rcu_old_gp_ongoing(long *value)
+static inline int rcu_gp_ongoing(unsigned long *value)
 {
-	long v;
+	unsigned long v;
 
 	if (value == NULL)
 		return 0;
@@ -239,7 +259,7 @@ static inline int rcu_old_gp_ongoing(long *value)
 
 static inline void _rcu_read_lock(void)
 {
-	long tmp;
+	unsigned long tmp;
 
 	tmp = rcu_reader.ctr;
 	/*
@@ -250,9 +270,9 @@ static inline void _rcu_read_lock(void)
 		_STORE_SHARED(rcu_reader.ctr, _LOAD_SHARED(rcu_gp_ctr));
 		/*
 		 * Set active readers count for outermost nesting level before
-		 * accessing the pointer. See smp_mb_heavy().
+		 * accessing the pointer. See smp_mb_master().
 		 */
-		smp_mb_light();
+		smp_mb_slave(RCU_MB_GROUP);
 	} else {
 		_STORE_SHARED(rcu_reader.ctr, tmp + RCU_GP_COUNT);
 	}
@@ -260,18 +280,18 @@ static inline void _rcu_read_lock(void)
 
 static inline void _rcu_read_unlock(void)
 {
-	long tmp;
+	unsigned long tmp;
 
 	tmp = rcu_reader.ctr;
 	/*
 	 * Finish using rcu before decrementing the pointer.
-	 * See smp_mb_heavy().
+	 * See smp_mb_master().
 	 */
 	if (likely((tmp & RCU_GP_CTR_NEST_MASK) == RCU_GP_COUNT)) {
-		smp_mb_light();
+		smp_mb_slave(RCU_MB_GROUP);
 		_STORE_SHARED(rcu_reader.ctr, rcu_reader.ctr - RCU_GP_COUNT);
 		/* write rcu_reader.ctr before read futex */
-		smp_mb_light();
+		smp_mb_slave(RCU_MB_GROUP);
 		wake_up_gp();
 	} else {
 		_STORE_SHARED(rcu_reader.ctr, rcu_reader.ctr - RCU_GP_COUNT);