[dpdk-dev] [PATCH v4 2/2] hash: unify crc32 selection for x86 and Arm

[pbhagavatula at marvell.com]

From: Pavan Nikhilesh <pbhagavatula at marvell.com>

Merge crc32 hash calculation public API implementation for x86 and Arm.
Select the best available CRC32 algorithm when unsupported algorithm
on a given CPU architecture is requested by an application.

Previously, if an application directly includes `rte_crc_arm64.h`
without including `rte_hash_crc.h` it will fail to compile.

Signed-off-by: Pavan Nikhilesh <pbhagavatula at marvell.com>
---
 lib/hash/hash_crc_arm64.h |  48 ++++++++++
 lib/hash/meson.build      |   1 -
 lib/hash/rte_crc_arm64.h  | 183 --------------------------------------
 lib/hash/rte_hash_crc.h   |  81 +++++++++++++----
 4 files changed, 112 insertions(+), 201 deletions(-)
 create mode 100644 lib/hash/hash_crc_arm64.h
 delete mode 100644 lib/hash/rte_crc_arm64.h

diff --git a/lib/hash/hash_crc_arm64.h b/lib/hash/hash_crc_arm64.h
new file mode 100644
index 0000000000..29b61a07a9
--- /dev/null
+++ b/lib/hash/hash_crc_arm64.h
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2015 Cavium, Inc
+ */
+
+#ifndef _HASH_CRC_ARM64_H_
+#define _HASH_CRC_ARM64_H_
+
+static inline uint32_t
+crc32c_arm64_u8(uint8_t data, uint32_t init_val)
+{
+	__asm__ volatile(
+			"crc32cb %w[crc], %w[crc], %w[value]"
+			: [crc] "+r" (init_val)
+			: [value] "r" (data));
+	return init_val;
+}
+
+static inline uint32_t
+crc32c_arm64_u16(uint16_t data, uint32_t init_val)
+{
+	__asm__ volatile(
+			"crc32ch %w[crc], %w[crc], %w[value]"
+			: [crc] "+r" (init_val)
+			: [value] "r" (data));
+	return init_val;
+}
+
+static inline uint32_t
+crc32c_arm64_u32(uint32_t data, uint32_t init_val)
+{
+	__asm__ volatile(
+			"crc32cw %w[crc], %w[crc], %w[value]"
+			: [crc] "+r" (init_val)
+			: [value] "r" (data));
+	return init_val;
+}
+
+static inline uint32_t
+crc32c_arm64_u64(uint64_t data, uint32_t init_val)
+{
+	__asm__ volatile(
+			"crc32cx %w[crc], %w[crc], %x[value]"
+			: [crc] "+r" (init_val)
+			: [value] "r" (data));
+	return init_val;
+}
+
+#endif /* _HASH_CRC_ARM64_H_ */
diff --git a/lib/hash/meson.build b/lib/hash/meson.build
index 9bc5ef925a..8794ea82a7 100644
--- a/lib/hash/meson.build
+++ b/lib/hash/meson.build
@@ -8,7 +8,6 @@ headers = files(
         'rte_jhash.h',
         'rte_thash.h',
 )
-indirect_headers += files('rte_crc_arm64.h')
 
 sources = files('rte_cuckoo_hash.c', 'rte_fbk_hash.c', 'rte_thash.c')
 deps += ['net']
diff --git a/lib/hash/rte_crc_arm64.h b/lib/hash/rte_crc_arm64.h
deleted file mode 100644
index b4628cfc09..0000000000
--- a/lib/hash/rte_crc_arm64.h
+++ /dev/null
@@ -1,183 +0,0 @@
-/* SPDX-License-Identifier: BSD-3-Clause
- * Copyright(c) 2015 Cavium, Inc
- */
-
-#ifndef _RTE_CRC_ARM64_H_
-#define _RTE_CRC_ARM64_H_
-
-/**
- * @file
- *
- * RTE CRC arm64 Hash
- */
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include <stdint.h>
-#include <rte_cpuflags.h>
-#include <rte_branch_prediction.h>
-#include <rte_common.h>
-
-static inline uint32_t
-crc32c_arm64_u8(uint8_t data, uint32_t init_val)
-{
-	__asm__ volatile(
-			"crc32cb %w[crc], %w[crc], %w[value]"
-			: [crc] "+r" (init_val)
-			: [value] "r" (data));
-	return init_val;
-}
-
-static inline uint32_t
-crc32c_arm64_u16(uint16_t data, uint32_t init_val)
-{
-	__asm__ volatile(
-			"crc32ch %w[crc], %w[crc], %w[value]"
-			: [crc] "+r" (init_val)
-			: [value] "r" (data));
-	return init_val;
-}
-
-static inline uint32_t
-crc32c_arm64_u32(uint32_t data, uint32_t init_val)
-{
-	__asm__ volatile(
-			"crc32cw %w[crc], %w[crc], %w[value]"
-			: [crc] "+r" (init_val)
-			: [value] "r" (data));
-	return init_val;
-}
-
-static inline uint32_t
-crc32c_arm64_u64(uint64_t data, uint32_t init_val)
-{
-	__asm__ volatile(
-			"crc32cx %w[crc], %w[crc], %x[value]"
-			: [crc] "+r" (init_val)
-			: [value] "r" (data));
-	return init_val;
-}
-
-/**
- * Allow or disallow use of arm64 SIMD instrinsics for CRC32 hash
- * calculation.
- *
- * @param alg
- *   An OR of following flags:
- *   - (CRC32_SW) Don't use arm64 crc intrinsics
- *   - (CRC32_ARM64) Use ARMv8 CRC intrinsic if available
- *
- */
-static inline void
-rte_hash_crc_set_alg(uint8_t alg)
-{
-	switch (alg) {
-	case CRC32_ARM64:
-		if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_CRC32))
-			alg = CRC32_SW;
-		/* fall-through */
-	case CRC32_SW:
-		crc32_alg = alg;
-		/* fall-through */
-	default:
-		break;
-	}
-}
-
-/* Setting the best available algorithm */
-RTE_INIT(rte_hash_crc_init_alg)
-{
-	rte_hash_crc_set_alg(CRC32_ARM64);
-}
-
-/**
- * Use single crc32 instruction to perform a hash on a 1 byte value.
- * Fall back to software crc32 implementation in case arm64 crc intrinsics is
- * not supported
- *
- * @param data
- *   Data to perform hash on.
- * @param init_val
- *   Value to initialise hash generator.
- * @return
- *   32bit calculated hash value.
- */
-static inline uint32_t
-rte_hash_crc_1byte(uint8_t data, uint32_t init_val)
-{
-	if (likely(crc32_alg & CRC32_ARM64))
-		return crc32c_arm64_u8(data, init_val);
-
-	return crc32c_1byte(data, init_val);
-}
-
-/**
- * Use single crc32 instruction to perform a hash on a 2 bytes value.
- * Fall back to software crc32 implementation in case arm64 crc intrinsics is
- * not supported
- *
- * @param data
- *   Data to perform hash on.
- * @param init_val
- *   Value to initialise hash generator.
- * @return
- *   32bit calculated hash value.
- */
-static inline uint32_t
-rte_hash_crc_2byte(uint16_t data, uint32_t init_val)
-{
-	if (likely(crc32_alg & CRC32_ARM64))
-		return crc32c_arm64_u16(data, init_val);
-
-	return crc32c_2bytes(data, init_val);
-}
-
-/**
- * Use single crc32 instruction to perform a hash on a 4 byte value.
- * Fall back to software crc32 implementation in case arm64 crc intrinsics is
- * not supported
- *
- * @param data
- *   Data to perform hash on.
- * @param init_val
- *   Value to initialise hash generator.
- * @return
- *   32bit calculated hash value.
- */
-static inline uint32_t
-rte_hash_crc_4byte(uint32_t data, uint32_t init_val)
-{
-	if (likely(crc32_alg & CRC32_ARM64))
-		return crc32c_arm64_u32(data, init_val);
-
-	return crc32c_1word(data, init_val);
-}
-
-/**
- * Use single crc32 instruction to perform a hash on a 8 byte value.
- * Fall back to software crc32 implementation in case arm64 crc intrinsics is
- * not supported
- *
- * @param data
- *   Data to perform hash on.
- * @param init_val
- *   Value to initialise hash generator.
- * @return
- *   32bit calculated hash value.
- */
-static inline uint32_t
-rte_hash_crc_8byte(uint64_t data, uint32_t init_val)
-{
-	if (likely(crc32_alg == CRC32_ARM64))
-		return crc32c_arm64_u64(data, init_val);
-
-	return crc32c_2words(data, init_val);
-}
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _RTE_CRC_ARM64_H_ */
diff --git a/lib/hash/rte_hash_crc.h b/lib/hash/rte_hash_crc.h
index 1cc8f84fe2..a51f6d3cc4 100644
--- a/lib/hash/rte_hash_crc.h
+++ b/lib/hash/rte_hash_crc.h
@@ -16,10 +16,18 @@ extern "C" {
 #endif
 
 #include <stdint.h>
-#include <rte_config.h>
-#include <rte_cpuflags.h>
+
 #include <rte_branch_prediction.h>
 #include <rte_common.h>
+#include <rte_config.h>
+#include <rte_cpuflags.h>
+#include <rte_log.h>
+
+#if defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
+#include "hash_crc_arm64.h"
+#elif defined(RTE_ARCH_X86)
+#include "hash_crc_x86.h"
+#endif
 
 #include <hash_crc_sw.h>
 
@@ -31,37 +39,64 @@ extern "C" {
 
 static uint8_t crc32_alg = CRC32_SW;
 
-#if defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
-#include "rte_crc_arm64.h"
-#else
-#include "hash_crc_x86.h"
-
 /**
- * Allow or disallow use of SSE4.2 instrinsics for CRC32 hash
+ * Allow or disallow use of SSE4.2/ARMv8 intrinsics for CRC32 hash
  * calculation.
  *
  * @param alg
  *   An OR of following flags:
- *   - (CRC32_SW) Don't use SSE4.2 intrinsics
+ *   - (CRC32_SW) Don't use SSE4.2/ARMv8 intrinsics (default non-[x86/ARMv8])
  *   - (CRC32_SSE42) Use SSE4.2 intrinsics if available
- *   - (CRC32_SSE42_x64) Use 64-bit SSE4.2 intrinsic if available (default)
+ *   - (CRC32_SSE42_x64) Use 64-bit SSE4.2 intrinsic if available (default x86)
+ *   - (CRC32_ARM64) Use ARMv8 CRC intrinsic if available (default ARMv8)
  *
  */
 static inline void
 rte_hash_crc_set_alg(uint8_t alg)
 {
-#if defined(RTE_ARCH_X86)
-	if (alg == CRC32_SSE42_x64 &&
-			!rte_cpu_get_flag_enabled(RTE_CPUFLAG_EM64T))
-		alg = CRC32_SSE42;
+	switch (alg) {
+	case CRC32_SSE42_x64:
+	case CRC32_SSE42:
+#if defined RTE_ARCH_X86
+		if (!rte_cpu_get_flag_enabled(RTE_CPUFLAG_EM64T))
+			crc32_alg = CRC32_SSE42;
+		else
+			crc32_alg = alg;
+#endif
+#if defined RTE_ARCH_ARM64
+		RTE_LOG(WARNING, HASH,
+			"Incorrect CRC32 algorithm requested setting best available algorithm on the architecture\n");
+		rte_hash_crc_set_alg(CRC32_ARM64);
 #endif
-	crc32_alg = alg;
+		break;
+	case CRC32_ARM64:
+#if defined RTE_ARCH_ARM64
+		if (rte_cpu_get_flag_enabled(RTE_CPUFLAG_CRC32))
+			crc32_alg = CRC32_ARM64;
+#endif
+#if defined RTE_ARCH_X86
+		RTE_LOG(WARNING, HASH,
+			"Incorrect CRC32 algorithm requested setting best available algorithm on the architecture\n");
+		rte_hash_crc_set_alg(CRC32_SSE42_x64);
+#endif
+		break;
+	case CRC32_SW:
+	default:
+		crc32_alg = CRC32_SW;
+		break;
+	}
 }
 
 /* Setting the best available algorithm */
 RTE_INIT(rte_hash_crc_init_alg)
 {
+#if defined(RTE_ARCH_X86)
 	rte_hash_crc_set_alg(CRC32_SSE42_x64);
+#elif defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
+	rte_hash_crc_set_alg(CRC32_ARM64);
+#else
+	rte_hash_crc_set_alg(CRC32_SW);
+#endif
 }
 
 /**
@@ -82,6 +117,9 @@ rte_hash_crc_1byte(uint8_t data, uint32_t init_val)
 #if defined RTE_ARCH_X86
 	if (likely(crc32_alg & CRC32_SSE42))
 		return crc32c_sse42_u8(data, init_val);
+#elif defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
+	if (likely(crc32_alg & CRC32_ARM64))
+		return crc32c_arm64_u8(data, init_val);
 #endif
 
 	return crc32c_1byte(data, init_val);
@@ -105,6 +143,9 @@ rte_hash_crc_2byte(uint16_t data, uint32_t init_val)
 #if defined RTE_ARCH_X86
 	if (likely(crc32_alg & CRC32_SSE42))
 		return crc32c_sse42_u16(data, init_val);
+#elif defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
+	if (likely(crc32_alg & CRC32_ARM64))
+		return crc32c_arm64_u16(data, init_val);
 #endif
 
 	return crc32c_2bytes(data, init_val);
@@ -128,6 +169,9 @@ rte_hash_crc_4byte(uint32_t data, uint32_t init_val)
 #if defined RTE_ARCH_X86
 	if (likely(crc32_alg & CRC32_SSE42))
 		return crc32c_sse42_u32(data, init_val);
+#elif defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
+	if (likely(crc32_alg & CRC32_ARM64))
+		return crc32c_arm64_u32(data, init_val);
 #endif
 
 	return crc32c_1word(data, init_val);
@@ -158,11 +202,14 @@ rte_hash_crc_8byte(uint64_t data, uint32_t init_val)
 		return crc32c_sse42_u64_mimic(data, init_val);
 #endif
 
+#if defined(RTE_ARCH_ARM64) && defined(__ARM_FEATURE_CRC32)
+	if (likely(crc32_alg & CRC32_ARM64))
+		return crc32c_arm64_u64(data, init_val);
+#endif
+
 	return crc32c_2words(data, init_val);
 }
 
-#endif
-
 /**
  * Calculate CRC32 hash on user-supplied byte array.
  *
-- 
2.17.1