[dpdk-dev] [PATCH v2 1/6] lib/eal: implement the family of rte bit operation APIs

Joyce Kong joyce.kong at arm.com
Wed Oct 23 04:54:53 CEST 2019


There are a lot functions of bit operations scattered and
duplicated in PMDs, consolidating them into a common API
family is necessary. Furthermore, the bit operation is
mostly applied to the IO devices, so use __ATOMIC_ACQ_REL
to ensure the ordering.

Signed-off-by: Joyce Kong <joyce.kong at arm.com>
Reviewed-by: Gavin Hu <gavin.hu at arm.com>
---
 lib/librte_eal/common/Makefile                |   1 +
 lib/librte_eal/common/include/rte_io_bitops.h | 112 ++++++++++++++++++++++++++
 lib/librte_eal/common/meson.build             |   1 +
 3 files changed, 114 insertions(+)
 create mode 100644 lib/librte_eal/common/include/rte_io_bitops.h

diff --git a/lib/librte_eal/common/Makefile b/lib/librte_eal/common/Makefile
index a00d4fc..3831313 100644
--- a/lib/librte_eal/common/Makefile
+++ b/lib/librte_eal/common/Makefile
@@ -18,6 +18,7 @@ INC += rte_malloc.h rte_keepalive.h rte_time.h
 INC += rte_service.h rte_service_component.h
 INC += rte_bitmap.h rte_vfio.h rte_hypervisor.h rte_test.h
 INC += rte_reciprocal.h rte_fbarray.h rte_uuid.h
+INC += rte_io_bitops.h
 
 GENERIC_INC := rte_atomic.h rte_byteorder.h rte_cycles.h rte_prefetch.h
 GENERIC_INC += rte_memcpy.h rte_cpuflags.h
diff --git a/lib/librte_eal/common/include/rte_io_bitops.h b/lib/librte_eal/common/include/rte_io_bitops.h
new file mode 100644
index 0000000..5f778b8
--- /dev/null
+++ b/lib/librte_eal/common/include/rte_io_bitops.h
@@ -0,0 +1,112 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2019 Arm Limited
+ */
+
+#ifndef _RTE_IO_BITOPS_H_
+#define _RTE_IO_BITOPS_H_
+
+/**
+ * @file
+ * Bit Operations
+ *
+ * This file defines a generic API for bit operations.
+ */
+
+#include <rte_lcore.h>
+
+/**
+ * Get a bit.
+ *
+ * @param nr
+ *   The bit to get.
+ * @param addr
+ *   The address to count from.
+ * @return
+ *   The value of the bit.
+ */
+static inline int32_t
+rte_io_get_bit(uint32_t nr, uint64_t *addr)
+{
+	return __atomic_load_n(addr, __ATOMIC_ACQUIRE) & (1UL << nr);
+}
+
+/**
+ * Set a bit to 1.
+ *
+ * @param nr
+ *   The bit to set.
+ * @param addr
+ *   The address to count from.
+ */
+static inline void
+rte_io_set_bit(uint32_t nr, uint64_t *addr)
+{
+	__atomic_fetch_or(addr, (1UL << nr), __ATOMIC_ACQ_REL);
+}
+
+/**
+ * Set a bit to 0.
+ *
+ * @param nr
+ *   The bit to set.
+ * @param addr
+ *   The address to count from.
+ */
+static inline void
+rte_io_clear_bit(int32_t nr, uint64_t *addr)
+{
+	__atomic_fetch_and(addr, ~(1UL << nr), __ATOMIC_ACQ_REL);
+}
+
+/**
+ * Test if a bit is 1.
+ *
+ * @param nr
+ *   The bit to test.
+ * @param addr
+ *   The address to count from.
+ * @return
+ *   1 if the bit is 1; else 0.
+ */
+static inline int32_t
+rte_io_test_bit(int32_t nr, uint64_t *addr)
+{
+	return (__atomic_load_n(addr, __ATOMIC_ACQUIRE) & (1UL << nr)) != 0;
+}
+
+/**
+ * Set a bit to 1 and return its old value.
+ *
+ * @param nr
+ *   The bit to set.
+ * @param addr
+ *   The address to count from.
+ * @return
+ *   The old value of the bit.
+ */
+static inline int32_t
+rte_io_test_and_set_bit(int32_t nr, uint64_t *addr)
+{
+	unsigned long mask = (1UL << nr);
+
+	return __atomic_fetch_or(addr, mask, __ATOMIC_ACQ_REL) & mask;
+}
+
+/**
+ * Set a bit to 0 and return its old value.
+ *
+ * @param nr
+ *   The bit to set.
+ * @param addr
+ *   The address to count from.
+ * @return
+ *   The old value of the bit.
+ */
+static inline int32_t
+rte_io_test_and_clear_bit(int32_t nr, uint64_t *addr)
+{
+	unsigned long mask = (1UL << nr);
+
+	return __atomic_fetch_and(addr, ~mask, __ATOMIC_ACQ_REL) & mask;
+}
+#endif /* _RTE_IO_BITOPS_H_ */
diff --git a/lib/librte_eal/common/meson.build b/lib/librte_eal/common/meson.build
index 386577c..0a65d04 100644
--- a/lib/librte_eal/common/meson.build
+++ b/lib/librte_eal/common/meson.build
@@ -52,6 +52,7 @@ common_headers = files(
 	'include/rte_alarm.h',
 	'include/rte_branch_prediction.h',
 	'include/rte_bus.h',
+	'include/rte_io_bitops.h',
 	'include/rte_bitmap.h',
 	'include/rte_class.h',
 	'include/rte_common.h',
-- 
2.7.4



More information about the dev mailing list