[dpdk-dev] [PATCH v4 1/5] eal: add new definitions for wait scheme
Feifei Wang
feifei.wang2 at arm.com
Wed Oct 20 10:45:19 CEST 2021
Introduce macros as generic interface for address monitoring.
Signed-off-by: Feifei Wang <feifei.wang2 at arm.com>
Reviewed-by: Ruifeng Wang <ruifeng.wang at arm.com>
---
lib/eal/arm/include/rte_pause_64.h | 126 ++++++++++++++++------------
lib/eal/include/generic/rte_pause.h | 32 +++++++
2 files changed, 104 insertions(+), 54 deletions(-)
diff --git a/lib/eal/arm/include/rte_pause_64.h b/lib/eal/arm/include/rte_pause_64.h
index e87d10b8cc..23954c2de2 100644
--- a/lib/eal/arm/include/rte_pause_64.h
+++ b/lib/eal/arm/include/rte_pause_64.h
@@ -31,20 +31,12 @@ static inline void rte_pause(void)
/* Put processor into low power WFE(Wait For Event) state. */
#define __WFE() { asm volatile("wfe" : : : "memory"); }
-static __rte_always_inline void
-rte_wait_until_equal_16(volatile uint16_t *addr, uint16_t expected,
- int memorder)
-{
- uint16_t value;
-
- assert(memorder == __ATOMIC_ACQUIRE || memorder == __ATOMIC_RELAXED);
-
- /*
- * Atomic exclusive load from addr, it returns the 16-bit content of
- * *addr while making it 'monitored',when it is written by someone
- * else, the 'monitored' state is cleared and a event is generated
- * implicitly to exit WFE.
- */
+/*
+ * Atomic exclusive load from addr, it returns the 16-bit content of
+ * *addr while making it 'monitored', when it is written by someone
+ * else, the 'monitored' state is cleared and a event is generated
+ * implicitly to exit WFE.
+ */
#define __LOAD_EXC_16(src, dst, memorder) { \
if (memorder == __ATOMIC_RELAXED) { \
asm volatile("ldxrh %w[tmp], [%x[addr]]" \
@@ -58,6 +50,52 @@ rte_wait_until_equal_16(volatile uint16_t *addr, uint16_t expected,
: "memory"); \
} }
+/*
+ * Atomic exclusive load from addr, it returns the 32-bit content of
+ * *addr while making it 'monitored', when it is written by someone
+ * else, the 'monitored' state is cleared and a event is generated
+ * implicitly to exit WFE.
+ */
+#define __LOAD_EXC_32(src, dst, memorder) { \
+ if (memorder == __ATOMIC_RELAXED) { \
+ asm volatile("ldxr %w[tmp], [%x[addr]]" \
+ : [tmp] "=&r" (dst) \
+ : [addr] "r"(src) \
+ : "memory"); \
+ } else { \
+ asm volatile("ldaxr %w[tmp], [%x[addr]]" \
+ : [tmp] "=&r" (dst) \
+ : [addr] "r"(src) \
+ : "memory"); \
+ } }
+
+/*
+ * Atomic exclusive load from addr, it returns the 64-bit content of
+ * *addr while making it 'monitored', when it is written by someone
+ * else, the 'monitored' state is cleared and a event is generated
+ * implicitly to exit WFE.
+ */
+#define __LOAD_EXC_64(src, dst, memorder) { \
+ if (memorder == __ATOMIC_RELAXED) { \
+ asm volatile("ldxr %x[tmp], [%x[addr]]" \
+ : [tmp] "=&r" (dst) \
+ : [addr] "r"(src) \
+ : "memory"); \
+ } else { \
+ asm volatile("ldaxr %x[tmp], [%x[addr]]" \
+ : [tmp] "=&r" (dst) \
+ : [addr] "r"(src) \
+ : "memory"); \
+ } }
+
+static __rte_always_inline void
+rte_wait_until_equal_16(volatile uint16_t *addr, uint16_t expected,
+ int memorder)
+{
+ uint16_t value;
+
+ assert(memorder == __ATOMIC_ACQUIRE || memorder == __ATOMIC_RELAXED);
+
__LOAD_EXC_16(addr, value, memorder)
if (value != expected) {
__SEVL()
@@ -66,7 +104,6 @@ rte_wait_until_equal_16(volatile uint16_t *addr, uint16_t expected,
__LOAD_EXC_16(addr, value, memorder)
} while (value != expected);
}
-#undef __LOAD_EXC_16
}
static __rte_always_inline void
@@ -77,25 +114,6 @@ rte_wait_until_equal_32(volatile uint32_t *addr, uint32_t expected,
assert(memorder == __ATOMIC_ACQUIRE || memorder == __ATOMIC_RELAXED);
- /*
- * Atomic exclusive load from addr, it returns the 32-bit content of
- * *addr while making it 'monitored',when it is written by someone
- * else, the 'monitored' state is cleared and a event is generated
- * implicitly to exit WFE.
- */
-#define __LOAD_EXC_32(src, dst, memorder) { \
- if (memorder == __ATOMIC_RELAXED) { \
- asm volatile("ldxr %w[tmp], [%x[addr]]" \
- : [tmp] "=&r" (dst) \
- : [addr] "r"(src) \
- : "memory"); \
- } else { \
- asm volatile("ldaxr %w[tmp], [%x[addr]]" \
- : [tmp] "=&r" (dst) \
- : [addr] "r"(src) \
- : "memory"); \
- } }
-
__LOAD_EXC_32(addr, value, memorder)
if (value != expected) {
__SEVL()
@@ -104,7 +122,6 @@ rte_wait_until_equal_32(volatile uint32_t *addr, uint32_t expected,
__LOAD_EXC_32(addr, value, memorder)
} while (value != expected);
}
-#undef __LOAD_EXC_32
}
static __rte_always_inline void
@@ -115,25 +132,6 @@ rte_wait_until_equal_64(volatile uint64_t *addr, uint64_t expected,
assert(memorder == __ATOMIC_ACQUIRE || memorder == __ATOMIC_RELAXED);
- /*
- * Atomic exclusive load from addr, it returns the 64-bit content of
- * *addr while making it 'monitored',when it is written by someone
- * else, the 'monitored' state is cleared and a event is generated
- * implicitly to exit WFE.
- */
-#define __LOAD_EXC_64(src, dst, memorder) { \
- if (memorder == __ATOMIC_RELAXED) { \
- asm volatile("ldxr %x[tmp], [%x[addr]]" \
- : [tmp] "=&r" (dst) \
- : [addr] "r"(src) \
- : "memory"); \
- } else { \
- asm volatile("ldaxr %x[tmp], [%x[addr]]" \
- : [tmp] "=&r" (dst) \
- : [addr] "r"(src) \
- : "memory"); \
- } }
-
__LOAD_EXC_64(addr, value, memorder)
if (value != expected) {
__SEVL()
@@ -143,6 +141,26 @@ rte_wait_until_equal_64(volatile uint64_t *addr, uint64_t expected,
} while (value != expected);
}
}
+
+#define rte_wait_event(addr, mask, expected, cond, memorder, size) \
+do { \
+ RTE_BUILD_BUG_ON(!__builtin_constant_p(memorder)); \
+ RTE_BUILD_BUG_ON(memorder != __ATOMIC_ACQUIRE && \
+ memorder != __ATOMIC_RELAXED); \
+ RTE_BUILD_BUG_ON(size != 16 && size != 32 && size != 64); \
+ uint##size_t value; \
+ __LOAD_EXC_##size(addr, value, memorder) \
+ if ((value & mask) cond expected) { \
+ __SEVL() \
+ do { \
+ __WFE() \
+ __LOAD_EXC_##size(addr, value, memorder) \
+ } while ((value & mask) cond expected); \
+ } \
+} while (0)
+
+#undef __LOAD_EXC_16
+#undef __LOAD_EXC_32
#undef __LOAD_EXC_64
#undef __SEVL
diff --git a/lib/eal/include/generic/rte_pause.h b/lib/eal/include/generic/rte_pause.h
index 668ee4a184..20a5d2a9fd 100644
--- a/lib/eal/include/generic/rte_pause.h
+++ b/lib/eal/include/generic/rte_pause.h
@@ -111,6 +111,38 @@ rte_wait_until_equal_64(volatile uint64_t *addr, uint64_t expected,
while (__atomic_load_n(addr, memorder) != expected)
rte_pause();
}
+
+/*
+ * Wait until *addr breaks the condition, with a relaxed memory
+ * ordering model meaning the loads around this API can be reordered.
+ *
+ * @param addr
+ * A pointer to the memory location.
+ * @param mask
+ * A mask of value bits in interest.
+ * @param expected
+ * A 16-bit expected value to be in the memory location.
+ * @param cond
+ * A symbol representing the condition (==, !=).
+ * @param memorder
+ * Two different memory orders that can be specified:
+ * __ATOMIC_ACQUIRE and __ATOMIC_RELAXED. These map to
+ * C++11 memory orders with the same names, see the C++11 standard or
+ * the GCC wiki on atomic synchronization for detailed definition.
+ * @param size
+ * The bit size of *addr:
+ * It is used for arm architecture to choose load instructions,
+ * and the optional value is 16, 32 and 64.
+ */
+#define rte_wait_event(addr, mask, expected, cond, memorder, size) \
+do { \
+ RTE_BUILD_BUG_ON(!__builtin_constant_p(memorder)); \
+ RTE_BUILD_BUG_ON(memorder != __ATOMIC_ACQUIRE && \
+ memorder != __ATOMIC_RELAXED); \
+ RTE_BUILD_BUG_ON(size != 16 && size != 32 && size != 64); \
+ while ((__atomic_load_n(addr, memorder) & mask) cond expected) \
+ rte_pause(); \
+} while (0)
#endif
#endif /* _RTE_PAUSE_H_ */
--
2.25.1
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