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Diffstat (limited to '')
| -rw-r--r-- | src/rocksdb/util/crc32c_arm64.cc | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/src/rocksdb/util/crc32c_arm64.cc b/src/rocksdb/util/crc32c_arm64.cc new file mode 100644 index 000000000..566810f4b --- /dev/null +++ b/src/rocksdb/util/crc32c_arm64.cc @@ -0,0 +1,165 @@ +// Copyright (c) 2018, Arm Limited and affiliates. All rights reserved. +// This source code is licensed under both the GPLv2 (found in the +// COPYING file in the root directory) and Apache 2.0 License +// (found in the LICENSE.Apache file in the root directory). + +#include "util/crc32c_arm64.h" + +#if defined(__linux__) && defined(HAVE_ARM64_CRC) + +#include <asm/hwcap.h> +#ifdef ROCKSDB_AUXV_GETAUXVAL_PRESENT +#include <sys/auxv.h> +#endif +#ifndef HWCAP_CRC32 +#define HWCAP_CRC32 (1 << 7) +#endif +#ifndef HWCAP_PMULL +#define HWCAP_PMULL (1 << 4) +#endif + +#ifdef HAVE_ARM64_CRYPTO +/* unfolding to compute 8 * 3 = 24 bytes parallelly */ +#define CRC32C24BYTES(ITR) \ + crc1 = crc32c_u64(crc1, *(buf64 + BLK_LENGTH + (ITR))); \ + crc2 = crc32c_u64(crc2, *(buf64 + BLK_LENGTH * 2 + (ITR))); \ + crc0 = crc32c_u64(crc0, *(buf64 + (ITR))); + +/* unfolding to compute 24 * 7 = 168 bytes parallelly */ +#define CRC32C7X24BYTES(ITR) \ + do { \ + CRC32C24BYTES((ITR)*7 + 0) \ + CRC32C24BYTES((ITR)*7 + 1) \ + CRC32C24BYTES((ITR)*7 + 2) \ + CRC32C24BYTES((ITR)*7 + 3) \ + CRC32C24BYTES((ITR)*7 + 4) \ + CRC32C24BYTES((ITR)*7 + 5) \ + CRC32C24BYTES((ITR)*7 + 6) \ + } while (0) +#endif + +extern bool pmull_runtime_flag; + +uint32_t crc32c_runtime_check(void) { +#ifdef ROCKSDB_AUXV_GETAUXVAL_PRESENT + uint64_t auxv = getauxval(AT_HWCAP); + return (auxv & HWCAP_CRC32) != 0; +#else + return 0; +#endif +} + +bool crc32c_pmull_runtime_check(void) { +#ifdef ROCKSDB_AUXV_GETAUXVAL_PRESENT + uint64_t auxv = getauxval(AT_HWCAP); + return (auxv & HWCAP_PMULL) != 0; +#else + return false; +#endif +} + +#ifdef ROCKSDB_UBSAN_RUN +#if defined(__clang__) +__attribute__((__no_sanitize__("alignment"))) +#elif defined(__GNUC__) +__attribute__((__no_sanitize_undefined__)) +#endif +#endif +uint32_t crc32c_arm64(uint32_t crc, unsigned char const *data, + unsigned len) { + const uint8_t *buf8; + const uint64_t *buf64 = (uint64_t *)data; + int length = (int)len; + crc ^= 0xffffffff; + + /* + * Pmull runtime check here. + * Raspberry Pi supports crc32 but doesn't support pmull. + * Skip Crc32c Parallel computation if no crypto extension available. + */ + if (pmull_runtime_flag) { +/* Macro (HAVE_ARM64_CRYPTO) is used for compiling check */ +#ifdef HAVE_ARM64_CRYPTO +/* Crc32c Parallel computation + * Algorithm comes from Intel whitepaper: + * crc-iscsi-polynomial-crc32-instruction-paper + * + * Input data is divided into three equal-sized blocks + * Three parallel blocks (crc0, crc1, crc2) for 1024 Bytes + * One Block: 42(BLK_LENGTH) * 8(step length: crc32c_u64) bytes + */ +#define BLK_LENGTH 42 + while (length >= 1024) { + uint64_t t0, t1; + uint32_t crc0 = 0, crc1 = 0, crc2 = 0; + + /* Parallel Param: + * k0 = CRC32(x ^ (42 * 8 * 8 * 2 - 1)); + * k1 = CRC32(x ^ (42 * 8 * 8 - 1)); + */ + uint32_t k0 = 0xe417f38a, k1 = 0x8f158014; + + /* Prefetch data for following block to avoid cache miss */ + PREF1KL1((uint8_t *)buf64, 1024); + + /* First 8 byte for better pipelining */ + crc0 = crc32c_u64(crc, *buf64++); + + /* 3 blocks crc32c parallel computation + * Macro unfolding to compute parallelly + * 168 * 6 = 1008 (bytes) + */ + CRC32C7X24BYTES(0); + CRC32C7X24BYTES(1); + CRC32C7X24BYTES(2); + CRC32C7X24BYTES(3); + CRC32C7X24BYTES(4); + CRC32C7X24BYTES(5); + buf64 += (BLK_LENGTH * 3); + + /* Last 8 bytes */ + crc = crc32c_u64(crc2, *buf64++); + + t0 = (uint64_t)vmull_p64(crc0, k0); + t1 = (uint64_t)vmull_p64(crc1, k1); + + /* Merge (crc0, crc1, crc2) -> crc */ + crc1 = crc32c_u64(0, t1); + crc ^= crc1; + crc0 = crc32c_u64(0, t0); + crc ^= crc0; + + length -= 1024; + } + + if (length == 0) return crc ^ (0xffffffffU); +#endif + } // if Pmull runtime check here + + buf8 = (const uint8_t *)buf64; + while (length >= 8) { + crc = crc32c_u64(crc, *(const uint64_t *)buf8); + buf8 += 8; + length -= 8; + } + + /* The following is more efficient than the straight loop */ + if (length >= 4) { + crc = crc32c_u32(crc, *(const uint32_t *)buf8); + buf8 += 4; + length -= 4; + } + + if (length >= 2) { + crc = crc32c_u16(crc, *(const uint16_t *)buf8); + buf8 += 2; + length -= 2; + } + + if (length >= 1) crc = crc32c_u8(crc, *buf8); + + crc ^= 0xffffffff; + return crc; +} + +#endif |