-/*-
- * BSD LICENSE
- *
- * Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * * Neither the name of Intel Corporation nor the names of its
- * contributors may be used to endorse or promote products derived
- * from this software without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
- * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
- * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
- * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
- * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
- * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2010-2014 Intel Corporation
*/
#ifndef _RTE_ATOMIC_H_
*/
#include <stdint.h>
+#include <rte_common.h>
#ifdef __DOXYGEN__
+/** @name Memory Barrier
+ */
+///@{
/**
* General memory barrier.
*
* This function is architecture dependent.
*/
static inline void rte_rmb(void);
+///@}
+/** @name SMP Memory Barrier
+ */
+///@{
/**
* General memory barrier between lcores
*
* Guarantees that the LOAD and STORE operations that precede the
* rte_smp_mb() call are globally visible across the lcores
- * before the the LOAD and STORE operations that follows it.
+ * before the LOAD and STORE operations that follows it.
*/
static inline void rte_smp_mb(void);
*
* Guarantees that the STORE operations that precede the
* rte_smp_wmb() call are globally visible across the lcores
- * before the the STORE operations that follows it.
+ * before the STORE operations that follows it.
*/
static inline void rte_smp_wmb(void);
*
* Guarantees that the LOAD operations that precede the
* rte_smp_rmb() call are globally visible across the lcores
- * before the the LOAD operations that follows it.
+ * before the LOAD operations that follows it.
*/
static inline void rte_smp_rmb(void);
+///@}
+
+/** @name I/O Memory Barrier
+ */
+///@{
+/**
+ * General memory barrier for I/O device
+ *
+ * Guarantees that the LOAD and STORE operations that precede the
+ * rte_io_mb() call are visible to I/O device or CPU before the
+ * LOAD and STORE operations that follow it.
+ */
+static inline void rte_io_mb(void);
+
+/**
+ * Write memory barrier for I/O device
+ *
+ * Guarantees that the STORE operations that precede the
+ * rte_io_wmb() call are visible to I/O device before the STORE
+ * operations that follow it.
+ */
+static inline void rte_io_wmb(void);
+
+/**
+ * Read memory barrier for IO device
+ *
+ * Guarantees that the LOAD operations on I/O device that precede the
+ * rte_io_rmb() call are visible to CPU before the LOAD
+ * operations that follow it.
+ */
+static inline void rte_io_rmb(void);
+///@}
+
+/** @name Coherent I/O Memory Barrier
+ *
+ * Coherent I/O memory barrier is a lightweight version of I/O memory
+ * barriers which are system-wide data synchronization barriers. This
+ * is for only coherent memory domain between lcore and I/O device but
+ * it is same as the I/O memory barriers in most of architectures.
+ * However, some architecture provides even lighter barriers which are
+ * somewhere in between I/O memory barriers and SMP memory barriers.
+ * For example, in case of ARMv8, DMB(data memory barrier) instruction
+ * can have different shareability domains - inner-shareable and
+ * outer-shareable. And inner-shareable DMB fits for SMP memory
+ * barriers and outer-shareable DMB for coherent I/O memory barriers,
+ * which acts on coherent memory.
+ *
+ * In most cases, I/O memory barriers are safer but if operations are
+ * on coherent memory instead of incoherent MMIO region of a device,
+ * then coherent I/O memory barriers can be used and this could bring
+ * performance gain depending on architectures.
+ */
+///@{
+/**
+ * Write memory barrier for coherent memory between lcore and I/O device
+ *
+ * Guarantees that the STORE operations on coherent memory that
+ * precede the rte_cio_wmb() call are visible to I/O device before the
+ * STORE operations that follow it.
+ */
+static inline void rte_cio_wmb(void);
+
+/**
+ * Read memory barrier for coherent memory between lcore and I/O device
+ *
+ * Guarantees that the LOAD operations on coherent memory updated by
+ * I/O device that precede the rte_cio_rmb() call are visible to CPU
+ * before the LOAD operations that follow it.
+ */
+static inline void rte_cio_rmb(void);
+///@}
#endif /* __DOXYGEN__ */
}
#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(__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.
*/
}
#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(__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.
*/
}
#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(__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.
*/
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