From 1dda0ef6a70b2c1f6b01054d851ace22e99bb048 Mon Sep 17 00:00:00 2001 From: Andreas Dilger Date: Mon, 10 Aug 2020 18:32:18 -0600 Subject: [PATCH 1/1] LU-13127 ptlrpc: prefer crc32_le() over CryptoAPI Prefer to call the crc32_le() library function directly if available, instead of cfs_crypto_hash(CFS_HASH_ALG_CRC32). It is about 10x faster for the 156-byte struct ptlrpc_body being checked in this function. A test of small buffers in that compares the two implementations, run on a 2.9GHz Core i7-7820 shows the difference is significant here: buffer size 156 bytes 1536 bytes 4096 bytes 1 MiB -----------+------------+------------+-----------+----------- cfs_crypto | 182 MiB/s | 1794 MiB/s | 4163 MB/s | 9631 MiB/s crc32_le | 1947 MiB/s | 1871 MiB/s | 1867 MB/s | 1823 MiB/s This corresponds to 10x faster or 1/10 as many cycles for ptlrpc_body. The CryptoAPI speed crosses over around 1536 bytes, which is still 10x larger than the ptlrpc_body size, so it is unlikely to be faster here. Signed-off-by: Andreas Dilger Change-Id: I116fd6c148f15660dd7b7faefb86f9dd603ebbe5 Reviewed-on: https://review.whamcloud.com/39614 Reviewed-by: Sebastien Buisson Tested-by: jenkins Reviewed-by: Alexey Lyashkov Tested-by: Maloo Reviewed-by: Oleg Drokin --- lustre/ptlrpc/pack_generic.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/lustre/ptlrpc/pack_generic.c b/lustre/ptlrpc/pack_generic.c index 0e382c4..33b491c 100644 --- a/lustre/ptlrpc/pack_generic.c +++ b/lustre/ptlrpc/pack_generic.c @@ -40,9 +40,7 @@ #define DEBUG_SUBSYSTEM S_RPC -#ifndef CONFIG_CRYPTO_CRC32 #include -#endif #include @@ -1387,13 +1385,16 @@ __u32 lustre_msg_calc_cksum(struct lustre_msg *msg, __u32 buf) __u32 crc; LASSERTF(pb != NULL, "invalid msg %p: no ptlrpc body!\n", msg); -#ifdef CONFIG_CRYPTO_CRC32 +#if IS_ENABLED(CONFIG_CRC32) + /* about 10x faster than crypto_hash for small buffers */ + crc = crc32_le(~(__u32)0, (unsigned char *)pb, len); +#elif IS_ENABLED(CONFIG_CRYPTO_CRC32) unsigned int hsize = 4; cfs_crypto_hash_digest(CFS_HASH_ALG_CRC32, (unsigned char *)pb, len, NULL, 0, (unsigned char *)&crc, &hsize); #else - crc = crc32_le(~(__u32)0, (unsigned char *)pb, len); +#error "need either CONFIG_CRC32 or CONFIG_CRYPTO_CRC32 enabled in the kernel" #endif return crc; } -- 1.8.3.1