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-rw-r--r--include/asm-generic/barrier.h27
1 files changed, 21 insertions, 6 deletions
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h
index 29458bbb2fa0..2cafdbb9ae4c 100644
--- a/include/asm-generic/barrier.h
+++ b/include/asm-generic/barrier.h
@@ -221,18 +221,17 @@ do { \
#endif
/**
- * smp_cond_load_acquire() - (Spin) wait for cond with ACQUIRE ordering
+ * smp_cond_load_relaxed() - (Spin) wait for cond with no ordering guarantees
* @ptr: pointer to the variable to wait on
* @cond: boolean expression to wait for
*
- * Equivalent to using smp_load_acquire() on the condition variable but employs
- * the control dependency of the wait to reduce the barrier on many platforms.
+ * Equivalent to using READ_ONCE() on the condition variable.
*
* Due to C lacking lambda expressions we load the value of *ptr into a
* pre-named variable @VAL to be used in @cond.
*/
-#ifndef smp_cond_load_acquire
-#define smp_cond_load_acquire(ptr, cond_expr) ({ \
+#ifndef smp_cond_load_relaxed
+#define smp_cond_load_relaxed(ptr, cond_expr) ({ \
typeof(ptr) __PTR = (ptr); \
typeof(*ptr) VAL; \
for (;;) { \
@@ -241,10 +240,26 @@ do { \
break; \
cpu_relax(); \
} \
- smp_acquire__after_ctrl_dep(); \
VAL; \
})
#endif
+/**
+ * smp_cond_load_acquire() - (Spin) wait for cond with ACQUIRE ordering
+ * @ptr: pointer to the variable to wait on
+ * @cond: boolean expression to wait for
+ *
+ * Equivalent to using smp_load_acquire() on the condition variable but employs
+ * the control dependency of the wait to reduce the barrier on many platforms.
+ */
+#ifndef smp_cond_load_acquire
+#define smp_cond_load_acquire(ptr, cond_expr) ({ \
+ typeof(*ptr) _val; \
+ _val = smp_cond_load_relaxed(ptr, cond_expr); \
+ smp_acquire__after_ctrl_dep(); \
+ _val; \
+})
+#endif
+
#endif /* !__ASSEMBLY__ */
#endif /* __ASM_GENERIC_BARRIER_H */