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From: "Mattias Rönnblom" <mattias.ronnblom@ericsson.com>
To: <dev@dpdk.org>
Cc: hofors@lysator.liu.se, "Heng Wang" <heng.wang@ericsson.com>,
	"Stephen Hemminger" <stephen@networkplumber.org>,
	"Tyler Retzlaff" <roretzla@linux.microsoft.com>,
	"Morten Brørup" <mb@smartsharesystems.com>,
	"Mattias Rönnblom" <mattias.ronnblom@ericsson.com>
Subject: [RFC v6 1/6] eal: extend bit manipulation functionality
Date: Thu, 2 May 2024 07:57:01 +0200	[thread overview]
Message-ID: <20240502055706.112443-2-mattias.ronnblom@ericsson.com> (raw)
In-Reply-To: <20240502055706.112443-1-mattias.ronnblom@ericsson.com>

Add functionality to test and modify the value of individual bits in
32-bit or 64-bit words.

These functions have no implications on memory ordering, atomicity and
does not use volatile and thus does not prevent any compiler
optimizations.

RFC v6:
 * Have rte_bit_test() accept const-marked bitsets.

RFC v4:
 * Add rte_bit_flip() which, believe it or not, flips the value of a bit.
 * Mark macro-generated private functions as experimental.
 * Use macros to generate *assign*() functions.

RFC v3:
 * Work around lack of C++ support for _Generic (Tyler Retzlaff).
 * Fix ','-related checkpatch warnings.

Signed-off-by: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
Acked-by: Morten Brørup <mb@smartsharesystems.com>
Acked-by: Tyler Retzlaff <roretzla@linux.microsoft.com>
---
 lib/eal/include/rte_bitops.h | 259 ++++++++++++++++++++++++++++++++++-
 1 file changed, 257 insertions(+), 2 deletions(-)

diff --git a/lib/eal/include/rte_bitops.h b/lib/eal/include/rte_bitops.h
index 449565eeae..3297133e22 100644
--- a/lib/eal/include/rte_bitops.h
+++ b/lib/eal/include/rte_bitops.h
@@ -2,6 +2,7 @@
  * Copyright(c) 2020 Arm Limited
  * Copyright(c) 2010-2019 Intel Corporation
  * Copyright(c) 2023 Microsoft Corporation
+ * Copyright(c) 2024 Ericsson AB
  */
 
 #ifndef _RTE_BITOPS_H_
@@ -11,12 +12,14 @@
  * @file
  * Bit Operations
  *
- * This file defines a family of APIs for bit operations
- * without enforcing memory ordering.
+ * This file provides functionality for low-level, single-word
+ * arithmetic and bit-level operations, such as counting or
+ * setting individual bits.
  */
 
 #include <stdint.h>
 
+#include <rte_compat.h>
 #include <rte_debug.h>
 
 #ifdef __cplusplus
@@ -105,6 +108,196 @@ extern "C" {
 #define RTE_FIELD_GET64(mask, reg) \
 		((typeof(mask))(((reg) & (mask)) >> rte_ctz64(mask)))
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Test bit in word.
+ *
+ * Generic selection macro to test the value of a bit in a 32-bit or
+ * 64-bit word. The type of operation depends on the type of the @c
+ * addr parameter.
+ *
+ * This macro does not give any guarantees in regards to memory
+ * ordering or atomicity.
+ *
+ * @param addr
+ *   A pointer to the word to modify.
+ * @param nr
+ *   The index of the bit.
+ */
+#define rte_bit_test(addr, nr)					\
+	_Generic((addr),					\
+		uint32_t *: __rte_bit_test32,			\
+		const uint32_t *: __rte_bit_test32,		\
+		uint64_t *: __rte_bit_test64,			\
+		const uint64_t *: __rte_bit_test64)(addr, nr)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Set bit in word.
+ *
+ * Generic selection macro to set a bit in a 32-bit or 64-bit
+ * word. The type of operation depends on the type of the @c addr
+ * parameter.
+ *
+ * This macro does not give any guarantees in regards to memory
+ * ordering or atomicity.
+ *
+ * @param addr
+ *   A pointer to the word to modify.
+ * @param nr
+ *   The index of the bit.
+ */
+#define rte_bit_set(addr, nr)				\
+	_Generic((addr),				\
+		 uint32_t *: __rte_bit_set32,		\
+		 uint64_t *: __rte_bit_set64)(addr, nr)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Clear bit in word.
+ *
+ * Generic selection macro to clear a bit in a 32-bit or 64-bit
+ * word. The type of operation depends on the type of the @c addr
+ * parameter.
+ *
+ * This macro does not give any guarantees in regards to memory
+ * ordering or atomicity.
+ *
+ * @param addr
+ *   A pointer to the word to modify.
+ * @param nr
+ *   The index of the bit.
+ */
+#define rte_bit_clear(addr, nr)					\
+	_Generic((addr),					\
+		 uint32_t *: __rte_bit_clear32,			\
+		 uint64_t *: __rte_bit_clear64)(addr, nr)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Assign a value to a bit in word.
+ *
+ * Generic selection macro to assign a value to a bit in a 32-bit or 64-bit
+ * word. The type of operation depends on the type of the @c addr parameter.
+ *
+ * This macro does not give any guarantees in regards to memory
+ * ordering or atomicity.
+ *
+ * @param addr
+ *   A pointer to the word to modify.
+ * @param nr
+ *   The index of the bit.
+ * @param value
+ *   The new value of the bit - true for '1', or false for '0'.
+ */
+#define rte_bit_assign(addr, nr, value)					\
+	_Generic((addr),						\
+		 uint32_t *: __rte_bit_assign32,			\
+		 uint64_t *: __rte_bit_assign64)(addr, nr, value)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Flip a bit in word.
+ *
+ * Generic selection macro to change the value of a bit to '0' if '1'
+ * or '1' if '0' in a 32-bit or 64-bit word. The type of operation
+ * depends on the type of the @c addr parameter.
+ *
+ * This macro does not give any guarantees in regards to memory
+ * ordering or atomicity.
+ *
+ * @param addr
+ *   A pointer to the word to modify.
+ * @param nr
+ *   The index of the bit.
+ */
+#define rte_bit_flip(addr, nr)						\
+	_Generic((addr),						\
+		 uint32_t *: __rte_bit_flip32,				\
+		 uint64_t *: __rte_bit_flip64)(addr, nr)
+
+#define __RTE_GEN_BIT_TEST(family, fun, qualifier, size)		\
+	__rte_experimental						\
+	static inline bool						\
+	__rte_bit_ ## family ## fun ## size(const qualifier uint ## size ## _t *addr, \
+					    unsigned int nr)		\
+	{								\
+		RTE_ASSERT(nr < size);					\
+									\
+		uint ## size ## _t mask = (uint ## size ## _t)1 << nr;	\
+		return *addr & mask;					\
+	}
+
+#define __RTE_GEN_BIT_SET(family, fun, qualifier, size)			\
+	__rte_experimental						\
+	static inline void						\
+	__rte_bit_ ## family ## fun ## size(qualifier uint ## size ## _t *addr, \
+					    unsigned int nr)		\
+	{								\
+		RTE_ASSERT(nr < size);					\
+									\
+		uint ## size ## _t mask = (uint ## size ## _t)1 << nr;	\
+		*addr |= mask;						\
+	}								\
+
+#define __RTE_GEN_BIT_CLEAR(family, fun, qualifier, size)		\
+	__rte_experimental						\
+	static inline void						\
+	__rte_bit_ ## family ## fun ## size(qualifier uint ## size ## _t *addr, \
+					    unsigned int nr)		\
+	{								\
+		RTE_ASSERT(nr < size);					\
+									\
+		uint ## size ## _t mask = ~((uint ## size ## _t)1 << nr); \
+		(*addr) &= mask;					\
+	}								\
+
+#define __RTE_GEN_BIT_ASSIGN(family, fun, qualifier, size)		\
+	__rte_experimental						\
+	static inline void						\
+	__rte_bit_ ## family ## fun ## size(qualifier uint ## size ## _t *addr, \
+					    unsigned int nr, bool value) \
+	{								\
+		if (value)						\
+			__rte_bit_ ## family ## set ## size(addr, nr);	\
+		else							\
+			__rte_bit_ ## family ## clear ## size(addr, nr); \
+	}
+
+#define __RTE_GEN_BIT_FLIP(family, fun, qualifier, size)		\
+	__rte_experimental						\
+	static inline void						\
+	__rte_bit_ ## family ## fun ## size(qualifier uint ## size ## _t *addr, \
+					    unsigned int nr)		\
+	{								\
+		bool value;						\
+									\
+		value = __rte_bit_ ## family ## test ## size(addr, nr);	\
+		__rte_bit_ ## family ## assign ## size(addr, nr, !value); \
+	}
+
+__RTE_GEN_BIT_TEST(, test,, 32)
+__RTE_GEN_BIT_SET(, set,, 32)
+__RTE_GEN_BIT_CLEAR(, clear,, 32)
+__RTE_GEN_BIT_ASSIGN(, assign,, 32)
+__RTE_GEN_BIT_FLIP(, flip,, 32)
+
+__RTE_GEN_BIT_TEST(, test,, 64)
+__RTE_GEN_BIT_SET(, set,, 64)
+__RTE_GEN_BIT_CLEAR(, clear,, 64)
+__RTE_GEN_BIT_ASSIGN(, assign,, 64)
+__RTE_GEN_BIT_FLIP(, flip,, 64)
+
 /*------------------------ 32-bit relaxed operations ------------------------*/
 
 /**
@@ -787,6 +980,68 @@ rte_log2_u64(uint64_t v)
 
 #ifdef __cplusplus
 }
+
+/*
+ * Since C++ doesn't support generic selection (i.e., _Generic),
+ * function overloading is used instead. Such functions must be
+ * defined outside 'extern "C"' to be accepted by the compiler.
+ */
+
+#undef rte_bit_test
+#undef rte_bit_set
+#undef rte_bit_clear
+#undef rte_bit_assign
+#undef rte_bit_flip
+
+#define __RTE_BIT_OVERLOAD_SZ_2(fun, qualifier, size, arg1_type, arg1_name) \
+	static inline void						\
+	rte_bit_ ## fun(qualifier uint ## size ## _t *addr,		\
+			arg1_type arg1_name)				\
+	{								\
+		__rte_bit_ ## fun ## size(addr, arg1_name);		\
+	}
+
+#define __RTE_BIT_OVERLOAD_2(fun, qualifier, arg1_type, arg1_name)	\
+	__RTE_BIT_OVERLOAD_SZ_2(fun, qualifier, 32, arg1_type, arg1_name) \
+	__RTE_BIT_OVERLOAD_SZ_2(fun, qualifier, 64, arg1_type, arg1_name)
+
+#define __RTE_BIT_OVERLOAD_SZ_2R(fun, qualifier, size, ret_type, arg1_type, \
+				 arg1_name)				\
+	static inline ret_type						\
+	rte_bit_ ## fun(qualifier uint ## size ## _t *addr,		\
+			arg1_type arg1_name)				\
+	{								\
+		return __rte_bit_ ## fun ## size(addr, arg1_name);	\
+	}
+
+#define __RTE_BIT_OVERLOAD_2R(fun, qualifier, ret_type, arg1_type, arg1_name) \
+	__RTE_BIT_OVERLOAD_SZ_2R(fun, qualifier, 32, ret_type, arg1_type, \
+				 arg1_name)				\
+	__RTE_BIT_OVERLOAD_SZ_2R(fun, qualifier, 64, ret_type, arg1_type, \
+				 arg1_name)
+
+#define __RTE_BIT_OVERLOAD_SZ_3(fun, qualifier, size, arg1_type, arg1_name, \
+				arg2_type, arg2_name)			\
+	static inline void						\
+	rte_bit_ ## fun(uint ## size ## _t *addr, arg1_type arg1_name,	\
+			arg2_type arg2_name)				\
+	{								\
+		__rte_bit_ ## fun ## size(addr, arg1_name, arg2_name);	\
+	}
+
+#define __RTE_BIT_OVERLOAD_3(fun, qualifier, arg1_type, arg1_name, arg2_type, \
+			     arg2_name)					\
+	__RTE_BIT_OVERLOAD_SZ_3(fun, qualifier, 32, arg1_type, arg1_name, \
+				arg2_type, arg2_name)			\
+	__RTE_BIT_OVERLOAD_SZ_3(fun, qualifier, 64, arg1_type, arg1_name, \
+				arg2_type, arg2_name)
+
+__RTE_BIT_OVERLOAD_2R(test, const, bool, unsigned int, nr)
+__RTE_BIT_OVERLOAD_2(set,, unsigned int, nr)
+__RTE_BIT_OVERLOAD_2(clear,, unsigned int, nr)
+__RTE_BIT_OVERLOAD_3(assign,, unsigned int, nr, bool, value)
+__RTE_BIT_OVERLOAD_2(flip,, unsigned int, nr)
+
 #endif
 
 #endif /* _RTE_BITOPS_H_ */
-- 
2.34.1


  reply	other threads:[~2024-05-02  6:07 UTC|newest]

Thread overview: 90+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-02 13:53 [RFC 0/7] Improve EAL bit operations API Mattias Rönnblom
2024-03-02 13:53 ` [RFC 1/7] eal: extend bit manipulation functions Mattias Rönnblom
2024-03-02 17:05   ` Stephen Hemminger
2024-03-03  6:26     ` Mattias Rönnblom
2024-03-04 16:34       ` Tyler Retzlaff
2024-03-05 18:01         ` Mattias Rönnblom
2024-03-05 18:06           ` Tyler Retzlaff
2024-04-25  8:58   ` [RFC v2 0/6] Improve EAL bit operations API Mattias Rönnblom
2024-04-25  8:58     ` [RFC v2 1/6] eal: extend bit manipulation functionality Mattias Rönnblom
2024-04-29  9:51       ` [RFC v3 0/6] Improve EAL bit operations API Mattias Rönnblom
2024-04-29  9:51         ` [RFC v3 1/6] eal: extend bit manipulation functionality Mattias Rönnblom
2024-04-29 11:12           ` Morten Brørup
2024-04-30  9:55           ` [RFC v4 0/6] Improve EAL bit operations API Mattias Rönnblom
2024-04-30  9:55             ` [RFC v4 1/6] eal: extend bit manipulation functionality Mattias Rönnblom
2024-04-30 12:08               ` [RFC v5 0/6] Improve EAL bit operations API Mattias Rönnblom
2024-04-30 12:08                 ` [RFC v5 1/6] eal: extend bit manipulation functionality Mattias Rönnblom
2024-05-02  5:57                   ` [RFC v6 0/6] Improve EAL bit operations API Mattias Rönnblom
2024-05-02  5:57                     ` Mattias Rönnblom [this message]
2024-05-05  8:37                       ` [RFC v7 " Mattias Rönnblom
2024-05-05  8:37                         ` [RFC v7 1/6] eal: extend bit manipulation functionality Mattias Rönnblom
2024-05-05  8:37                         ` [RFC v7 2/6] eal: add unit tests for bit operations Mattias Rönnblom
2024-05-05  8:37                         ` [RFC v7 3/6] eal: add exactly-once bit access functions Mattias Rönnblom
2024-05-07 19:17                           ` Morten Brørup
2024-05-08  6:47                             ` Mattias Rönnblom
2024-05-08  7:33                               ` Morten Brørup
2024-05-08  8:00                                 ` Mattias Rönnblom
2024-05-08  8:11                                   ` Morten Brørup
2024-05-08  9:27                                     ` Mattias Rönnblom
2024-05-08 10:08                                       ` Morten Brørup
2024-05-08 15:15                                 ` Stephen Hemminger
2024-05-08 16:16                                   ` Morten Brørup
2024-05-05  8:37                         ` [RFC v7 4/6] eal: add unit tests for " Mattias Rönnblom
2024-05-05  8:37                         ` [RFC v7 5/6] eal: add atomic bit operations Mattias Rönnblom
2024-05-05  8:37                         ` [RFC v7 6/6] eal: add unit tests for atomic bit access functions Mattias Rönnblom
2024-05-02  5:57                     ` [RFC v6 2/6] eal: add unit tests for bit operations Mattias Rönnblom
2024-05-02  5:57                     ` [RFC v6 3/6] eal: add exactly-once bit access functions Mattias Rönnblom
2024-05-02  5:57                     ` [RFC v6 4/6] eal: add unit tests for " Mattias Rönnblom
2024-05-02  5:57                     ` [RFC v6 5/6] eal: add atomic bit operations Mattias Rönnblom
2024-05-03  6:41                       ` Mattias Rönnblom
2024-05-03 23:30                         ` Tyler Retzlaff
2024-05-04 15:36                           ` Mattias Rönnblom
2024-05-02  5:57                     ` [RFC v6 6/6] eal: add unit tests for atomic bit access functions Mattias Rönnblom
2024-04-30 12:08                 ` [RFC v5 2/6] eal: add unit tests for bit operations Mattias Rönnblom
2024-04-30 12:08                 ` [RFC v5 3/6] eal: add exactly-once bit access functions Mattias Rönnblom
2024-04-30 12:08                 ` [RFC v5 4/6] eal: add unit tests for " Mattias Rönnblom
2024-04-30 12:08                 ` [RFC v5 5/6] eal: add atomic bit operations Mattias Rönnblom
2024-04-30 12:08                 ` [RFC v5 6/6] eal: add unit tests for atomic bit access functions Mattias Rönnblom
2024-04-30  9:55             ` [RFC v4 2/6] eal: add unit tests for bit operations Mattias Rönnblom
2024-04-30  9:55             ` [RFC v4 3/6] eal: add exactly-once bit access functions Mattias Rönnblom
2024-04-30  9:55             ` [RFC v4 4/6] eal: add unit tests for " Mattias Rönnblom
2024-04-30 10:37               ` Morten Brørup
2024-04-30 11:58                 ` Mattias Rönnblom
2024-04-30  9:55             ` [RFC v4 5/6] eal: add atomic bit operations Mattias Rönnblom
2024-04-30  9:55             ` [RFC v4 6/6] eal: add unit tests for atomic bit access functions Mattias Rönnblom
2024-04-29  9:51         ` [RFC v3 2/6] eal: add unit tests for bit operations Mattias Rönnblom
2024-04-29  9:51         ` [RFC v3 3/6] eal: add exactly-once bit access functions Mattias Rönnblom
2024-04-29  9:51         ` [RFC v3 4/6] eal: add unit tests for " Mattias Rönnblom
2024-04-29  9:51         ` [RFC v3 5/6] eal: add atomic bit operations Mattias Rönnblom
2024-04-29  9:51         ` [RFC v3 6/6] eal: add unit tests for atomic bit access functions Mattias Rönnblom
2024-04-25  8:58     ` [RFC v2 2/6] eal: add unit tests for bit operations Mattias Rönnblom
2024-04-25  8:58     ` [RFC v2 3/6] eal: add exactly-once bit access functions Mattias Rönnblom
2024-04-25  8:58     ` [RFC v2 4/6] eal: add unit tests for " Mattias Rönnblom
2024-04-25  8:58     ` [RFC v2 5/6] eal: add atomic bit operations Mattias Rönnblom
2024-04-25 10:25       ` Morten Brørup
2024-04-25 14:36         ` Mattias Rönnblom
2024-04-25 16:18           ` Morten Brørup
2024-04-26  9:39             ` Mattias Rönnblom
2024-04-26 12:00               ` Morten Brørup
2024-04-28 15:37                 ` Mattias Rönnblom
2024-04-29  7:24                   ` Morten Brørup
2024-04-30 16:52               ` Tyler Retzlaff
2024-04-25  8:58     ` [RFC v2 6/6] eal: add unit tests for atomic bit access functions Mattias Rönnblom
2024-04-25 18:05     ` [RFC v2 0/6] Improve EAL bit operations API Tyler Retzlaff
2024-04-26 11:17       ` Mattias Rönnblom
2024-04-26 21:35     ` Patrick Robb
2024-03-02 13:53 ` [RFC 2/7] eal: add generic bit manipulation macros Mattias Rönnblom
2024-03-04  8:16   ` Heng Wang
2024-03-04 15:41     ` Mattias Rönnblom
2024-03-04 16:42   ` Tyler Retzlaff
2024-03-05 18:08     ` Mattias Rönnblom
2024-03-05 18:22       ` Tyler Retzlaff
2024-03-05 20:02         ` Mattias Rönnblom
2024-03-05 20:53           ` Tyler Retzlaff
2024-03-02 13:53 ` [RFC 3/7] eal: add bit manipulation functions which read or write once Mattias Rönnblom
2024-03-02 13:53 ` [RFC 4/7] eal: add generic once-type bit operations macros Mattias Rönnblom
2024-03-02 13:53 ` [RFC 5/7] eal: add atomic bit operations Mattias Rönnblom
2024-03-02 13:53 ` [RFC 6/7] eal: add generic " Mattias Rönnblom
2024-03-02 13:53 ` [RFC 7/7] eal: deprecate relaxed family of " Mattias Rönnblom
2024-03-02 17:07   ` Stephen Hemminger
2024-03-03  6:30     ` Mattias Rönnblom

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