Mercurial > hg > nginx-quic
view src/core/ngx_crc.h @ 8247:1823e2152fc4 quic
QUIC: always calculate rtt for largest acknowledged packet.
Previously, when processing client ACK, rtt could be calculated for a packet
different than the largest if it was missing in the sent chain. Even though
this is an unlikely situation, rtt based on a different packet could be larger
than needed leading to bigger pto timeout and performance degradation.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Wed, 09 Dec 2020 21:26:21 +0000 |
parents | d620f497c50f |
children |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #ifndef _NGX_CRC_H_INCLUDED_ #define _NGX_CRC_H_INCLUDED_ #include <ngx_config.h> #include <ngx_core.h> /* 32-bit crc16 */ static ngx_inline uint32_t ngx_crc(u_char *data, size_t len) { uint32_t sum; for (sum = 0; len; len--) { /* * gcc 2.95.2 x86 and icc 7.1.006 compile * that operator into the single "rol" opcode, * msvc 6.0sp2 compiles it into four opcodes. */ sum = sum >> 1 | sum << 31; sum += *data++; } return sum; } #endif /* _NGX_CRC_H_INCLUDED_ */