Add atomic bit test/set/clear/assign and test-and-set/clear functions.
All atomic bit functions allow (and indeed, require) the caller to
specify a memory order.
RFC v4:
* Add atomic bit flip.
* Mark macro-generated private functions experimental.
RFC v3:
* Work around lack of C++ support for _Generic (Tyler Retzlaff).
RFC v2:
o Add rte_bit_atomic_test_and_assign() (for consistency).
o Fix bugs in rte_bit_atomic_test_and_[set|clear]().
o Use <rte_stdatomics.h> to support MSVC.
Signed-off-by: Mattias Rönnblom <mattias.ronnb...@ericsson.com>
Acked-by: Morten Brørup <m...@smartsharesystems.com>
Acked-by: Tyler Retzlaff <roret...@linux.microsoft.com>
---
lib/eal/include/rte_bitops.h | 194 +++++++++++++++++++++++++++++++++++
1 file changed, 194 insertions(+)
diff --git a/lib/eal/include/rte_bitops.h b/lib/eal/include/rte_bitops.h
index abfe96d531..f014bd913e 100644
--- a/lib/eal/include/rte_bitops.h
+++ b/lib/eal/include/rte_bitops.h
@@ -589,6 +589,199 @@ extern "C" {
value, \
memory_order)
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Test if a particular bit in a word is set with a particular memory
+ * order.
+ *
+ * Test a bit with the resulting memory load ordered as per the
+ * specified memory order.
+ *
+ * @param addr
+ * A pointer to the word to query.
+ * @param nr
+ * The index of the bit.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ * @return
+ * Returns true if the bit is set, and false otherwise.
+ */
+#define rte_bit_atomic_test(addr, nr, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_test32, \
+ uint64_t *: __rte_bit_atomic_test64)(addr, nr, memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically set bit in word.
+ *
+ * Atomically set bit specified by @c nr in the word pointed to by @c
+ * addr to '1', with the memory ordering as specified by @c
+ * memory_order.
+ *
+ * @param addr
+ * A pointer to the word to modify.
+ * @param nr
+ * The index of the bit.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ */
+#define rte_bit_atomic_set(addr, nr, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_set32, \
+ uint64_t *: __rte_bit_atomic_set64)(addr, nr, memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically clear bit in word.
+ *
+ * Atomically set bit specified by @c nr in the word pointed to by @c
+ * addr to '0', with the memory ordering as specified by @c
+ * memory_order.
+ *
+ * @param addr
+ * A pointer to the word to modify.
+ * @param nr
+ * The index of the bit.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ */
+#define rte_bit_atomic_clear(addr, nr, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_clear32, \
+ uint64_t *: __rte_bit_atomic_clear64)(addr, nr, memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically assign a value to bit in word.
+ *
+ * Atomically set bit specified by @c nr in the word pointed to by @c
+ * addr to the value indicated by @c value, with the memory ordering
+ * as specified with @c memory_order.
+ *
+ * @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'.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ */
+#define rte_bit_atomic_assign(addr, nr, value, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_assign32, \
+ uint64_t *: __rte_bit_atomic_assign64)(addr, nr, value, \
+ memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically flip bit in word.
+ *
+ * Atomically negate the value of the bit specified by @c nr in the
+ * word pointed to by @c addr to the value indicated by @c value, with
+ * the memory ordering as specified with @c memory_order.
+ *
+ * @param addr
+ * A pointer to the word to modify.
+ * @param nr
+ * The index of the bit.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ */
+#define rte_bit_atomic_flip(addr, nr, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_flip32, \
+ uint64_t *: __rte_bit_atomic_flip64)(addr, nr, memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically test and set a bit in word.
+ *
+ * Atomically test and set bit specified by @c nr in the word pointed
+ * to by @c addr to '1', with the memory ordering as specified with @c
+ * memory_order.
+ *
+ * @param addr
+ * A pointer to the word to modify.
+ * @param nr
+ * The index of the bit.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ * @return
+ * Returns true if the bit was set, and false otherwise.
+ */
+#define rte_bit_atomic_test_and_set(addr, nr, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_test_and_set32, \
+ uint64_t *: __rte_bit_atomic_test_and_set64)(addr, nr, \
+ memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically test and clear a bit in word.
+ *
+ * Atomically test and clear bit specified by @c nr in the word
+ * pointed to by @c addr to '0', with the memory ordering as specified
+ * with @c memory_order.
+ *
+ * @param addr
+ * A pointer to the word to modify.
+ * @param nr
+ * The index of the bit.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ * @return
+ * Returns true if the bit was set, and false otherwise.
+ */
+#define rte_bit_atomic_test_and_clear(addr, nr, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_test_and_clear32, \
+ uint64_t *: __rte_bit_atomic_test_and_clear64)(addr, nr, \
+ memory_order)
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Atomically test and assign a bit in word.
+ *
+ * Atomically test and assign bit specified by @c nr in the word
+ * pointed to by @c addr the value specified by @c value, with the
+ * memory ordering as specified with @c memory_order.
+ *
+ * @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'.
+ * @param memory_order
+ * The memory order to use. See <rte_stdatomics.h> for details.
+ * @return
+ * Returns true if the bit was set, and false otherwise.
+ */
+#define rte_bit_atomic_test_and_assign(addr, nr, value, memory_order) \
+ _Generic((addr), \
+ uint32_t *: __rte_bit_atomic_test_and_assign32, \
+ uint64_t *: __rte_bit_atomic_test_and_assign64)(addr, nr, \
+ value, \
+ memory_order)
+
#define __RTE_GEN_BIT_TEST(family, fun, qualifier, size) \
__rte_experimental \
static inline bool \
@@ -1534,6 +1727,7 @@ rte_log2_u64(uint64_t v)
#undef rte_bit_atomic_set
#undef rte_bit_atomic_clear
#undef rte_bit_atomic_assign
+#undef rte_bit_atomic_flip
#undef rte_bit_atomic_test_and_set
#undef rte_bit_atomic_test_and_clear
#undef rte_bit_atomic_test_and_assign
--
2.34.1
