Turn *_REMOTE into *_SHARED

"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>:
I suspect that LOAD_SHARED() and STORE_SHARED() would be more intuitive.
But shouldn't we align with the Linux-kernel usage where reasonable?
(Yes, this can be a moving target, but there isn't much else that
currently supports this level of SMP function on quite the variety of
CPU architectures.)

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>

diff --git a/urcu.c b/urcu.c
index b04b121344c5e0d425c0d2cfaee34a662ecb8cbf..8cb32a117bb065405ca3f45e0224dfe8fbebbf5d 100644 (file)
--- a/urcu.c
+++ b/urcu.c
@@ -105,7 +105,7 @@ static void force_mb_single_thread(pthread_t tid)
         * Wait for sighandler (and thus mb()) to execute on every thread.
         * BUSY-LOOP.
         */
-       while (LOAD_REMOTE(sig_done) < 1)
+       while (LOAD_SHARED(sig_done) < 1)
                cpu_relax();
        smp_mb();       /* read sig_done before ending the barrier */
 }
@@ -134,7 +134,7 @@ static void force_mb_all_threads(void)
         * Wait for sighandler (and thus mb()) to execute on every thread.
         * BUSY-LOOP.
         */
-       while (LOAD_REMOTE(sig_done) < num_readers)
+       while (LOAD_SHARED(sig_done) < num_readers)
                cpu_relax();
        smp_mb();       /* read sig_done before ending the barrier */
 }

diff --git a/urcu.h b/urcu.h
index d72cbf61ac1df31d62a8c7a2fe00895d55216d9d..df270326675dafdf78a237ac72bceebc6b673274 100644 (file)
--- a/urcu.h
+++ b/urcu.h
@@ -180,19 +180,19 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
 #define ACCESS_ONCE(x) (*(volatile typeof(x) *)&(x))
 
 /*
- * Load a data from remote memory, doing a cache flush if required.
+ * Load a data from shared memory, doing a cache flush if required.
  */
-#define LOAD_REMOTE(p)        ({ \
+#define LOAD_SHARED(p)        ({ \
                                smp_rmc(); \
                                typeof(p) _________p1 = ACCESS_ONCE(p); \
                                (_________p1); \
                                })
 
 /*
- * Store v into x, where x is located in remote memory. Performs the required
+ * Store v into x, where x is located in shared memory. Performs the required
  * cache flush after writing.
  */
-#define STORE_REMOTE(x, v) \
+#define STORE_SHARED(x, v) \
        do { \
                (x) = (v); \
                smp_wmc; \
@@ -209,7 +209,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr,
  */
 
 #define rcu_dereference(p)     ({ \
-                               typeof(p) _________p1 = LOAD_REMOTE(p); \
+                               typeof(p) _________p1 = LOAD_SHARED(p); \
                                smp_read_barrier_depends(); \
                                (_________p1); \
                                })
@@ -318,7 +318,7 @@ static inline int rcu_old_gp_ongoing(long *value)
         * Make sure both tests below are done on the same version of *value
         * to insure consistency.
         */
-       v = LOAD_REMOTE(*value);
+       v = LOAD_SHARED(*value);
        return (v & RCU_GP_CTR_NEST_MASK) &&
                 ((v ^ urcu_gp_ctr) & RCU_GP_CTR_BIT);
 }
@@ -331,8 +331,8 @@ static inline void rcu_read_lock(void)
        /* urcu_gp_ctr = RCU_GP_COUNT | (~RCU_GP_CTR_BIT or RCU_GP_CTR_BIT) */
        /*
         * The data dependency "read urcu_gp_ctr, write urcu_active_readers",
-        * serializes those two memory operations. We are not using STORE_REMOTE
-        * and LOAD_REMOTE here (although we should) because the writer will
+        * serializes those two memory operations. We are not using STORE_SHARED
+        * and LOAD_SHARED here (although we should) because the writer will
         * wake us up with a signal which does a flush in its handler to perform
         * urcu_gp_ctr re-read and urcu_active_readers commit to main memory.
         */