X-Git-Url: https://gerrit.fd.io/r/gitweb?p=deb_dpdk.git;a=blobdiff_plain;f=lib%2Flibrte_eal%2Fcommon%2Finclude%2Fgeneric%2Frte_atomic.h;h=b99ba4688df12bfec454eaff512b59e444ed986e;hp=50e1b8a4d277041c2d4cc50c3398332deb8af325;hb=b63264c8342e6a1b6971c79550d2af2024b6a4de;hpb=ca33590b6af032bff57d9cc70455660466a654b2

diff --git a/lib/librte_eal/common/include/generic/rte_atomic.h b/lib/librte_eal/common/include/generic/rte_atomic.h
index 50e1b8a4..b99ba468 100644
--- a/lib/librte_eal/common/include/generic/rte_atomic.h
+++ b/lib/librte_eal/common/include/generic/rte_atomic.h
@@ -190,6 +190,36 @@ rte_atomic16_cmpset(volatile uint16_t *dst, uint16_t exp, uint16_t src)
 }
 #endif
 
+/**
+ * Atomic exchange.
+ *
+ * (atomic) equivalent to:
+ *   ret = *dst
+ *   *dst = val;
+ *   return ret;
+ *
+ * @param dst
+ *   The destination location into which the value will be written.
+ * @param val
+ *   The new value.
+ * @return
+ *   The original value at that location
+ */
+static inline uint16_t
+rte_atomic16_exchange(volatile uint16_t *dst, uint16_t val);
+
+#ifdef RTE_FORCE_INTRINSICS
+static inline uint16_t
+rte_atomic16_exchange(volatile uint16_t *dst, uint16_t val)
+{
+#if defined(RTE_ARCH_ARM64) && defined(RTE_TOOLCHAIN_CLANG)
+	return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
+#else
+	return __atomic_exchange_2(dst, val, __ATOMIC_SEQ_CST);
+#endif
+}
+#endif
+
 /**
  * The atomic counter structure.
  */
@@ -443,6 +473,36 @@ rte_atomic32_cmpset(volatile uint32_t *dst, uint32_t exp, uint32_t src)
 }
 #endif
 
+/**
+ * Atomic exchange.
+ *
+ * (atomic) equivalent to:
+ *   ret = *dst
+ *   *dst = val;
+ *   return ret;
+ *
+ * @param dst
+ *   The destination location into which the value will be written.
+ * @param val
+ *   The new value.
+ * @return
+ *   The original value at that location
+ */
+static inline uint32_t
+rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val);
+
+#ifdef RTE_FORCE_INTRINSICS
+static inline uint32_t
+rte_atomic32_exchange(volatile uint32_t *dst, uint32_t val)
+{
+#if defined(RTE_ARCH_ARM64) && defined(RTE_TOOLCHAIN_CLANG)
+	return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
+#else
+	return __atomic_exchange_4(dst, val, __ATOMIC_SEQ_CST);
+#endif
+}
+#endif
+
 /**
  * The atomic counter structure.
  */
@@ -695,6 +755,36 @@ rte_atomic64_cmpset(volatile uint64_t *dst, uint64_t exp, uint64_t src)
 }
 #endif
 
+/**
+ * Atomic exchange.
+ *
+ * (atomic) equivalent to:
+ *   ret = *dst
+ *   *dst = val;
+ *   return ret;
+ *
+ * @param dst
+ *   The destination location into which the value will be written.
+ * @param val
+ *   The new value.
+ * @return
+ *   The original value at that location
+ */
+static inline uint64_t
+rte_atomic64_exchange(volatile uint64_t *dst, uint64_t val);
+
+#ifdef RTE_FORCE_INTRINSICS
+static inline uint64_t
+rte_atomic64_exchange(volatile uint64_t *dst, uint64_t val)
+{
+#if defined(RTE_ARCH_ARM64) && defined(RTE_TOOLCHAIN_CLANG)
+	return __atomic_exchange_n(dst, val, __ATOMIC_SEQ_CST);
+#else
+	return __atomic_exchange_8(dst, val, __ATOMIC_SEQ_CST);
+#endif
+}
+#endif
+
 /**
  * The atomic counter structure.
  */