Mercurial > hg > nginx-quic
view src/core/ngx_bpf.c @ 8759:56dec0d4e5b1 quic
QUIC: avoid excessive buffer allocations in stream output.
Previously, when a few bytes were send to a QUIC stream by the application, a
4K buffer was allocated for these bytes. Then a STREAM frame was created and
that entire buffer was used as data for that frame. The frame with the buffer
were in use up until the frame was acked by client. Meanwhile, when more
bytes were send to the stream, more buffers were allocated and assigned as
data to newer STREAM frames. In this scenario most buffer memory is unused.
Now the unused part of the stream output buffer is available for further
stream output while earlier parts of the buffer are waiting to be acked.
This is achieved by splitting the output buffer.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Fri, 24 Dec 2021 18:13:51 +0300 |
parents | 7a07724256c2 |
children |
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/* * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #define NGX_BPF_LOGBUF_SIZE (16 * 1024) static ngx_inline int ngx_bpf(enum bpf_cmd cmd, union bpf_attr *attr, unsigned int size) { return syscall(__NR_bpf, cmd, attr, size); } void ngx_bpf_program_link(ngx_bpf_program_t *program, const char *symbol, int fd) { ngx_uint_t i; ngx_bpf_reloc_t *rl; rl = program->relocs; for (i = 0; i < program->nrelocs; i++) { if (ngx_strcmp(rl[i].name, symbol) == 0) { program->ins[rl[i].offset].src_reg = 1; program->ins[rl[i].offset].imm = fd; } } } int ngx_bpf_load_program(ngx_log_t *log, ngx_bpf_program_t *program) { int fd; union bpf_attr attr; #if (NGX_DEBUG) char buf[NGX_BPF_LOGBUF_SIZE]; #endif ngx_memzero(&attr, sizeof(union bpf_attr)); attr.license = (uintptr_t) program->license; attr.prog_type = program->type; attr.insns = (uintptr_t) program->ins; attr.insn_cnt = program->nins; #if (NGX_DEBUG) /* for verifier errors */ attr.log_buf = (uintptr_t) buf; attr.log_size = NGX_BPF_LOGBUF_SIZE; attr.log_level = 1; #endif fd = ngx_bpf(BPF_PROG_LOAD, &attr, sizeof(attr)); if (fd < 0) { ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "failed to load BPF program"); ngx_log_debug1(NGX_LOG_DEBUG_CORE, log, 0, "bpf verifier: %s", buf); return -1; } return fd; } int ngx_bpf_map_create(ngx_log_t *log, enum bpf_map_type type, int key_size, int value_size, int max_entries, uint32_t map_flags) { int fd; union bpf_attr attr; ngx_memzero(&attr, sizeof(union bpf_attr)); attr.map_type = type; attr.key_size = key_size; attr.value_size = value_size; attr.max_entries = max_entries; attr.map_flags = map_flags; fd = ngx_bpf(BPF_MAP_CREATE, &attr, sizeof(attr)); if (fd < 0) { ngx_log_error(NGX_LOG_ALERT, log, ngx_errno, "failed to create BPF map"); return NGX_ERROR; } return fd; } int ngx_bpf_map_update(int fd, const void *key, const void *value, uint64_t flags) { union bpf_attr attr; ngx_memzero(&attr, sizeof(union bpf_attr)); attr.map_fd = fd; attr.key = (uintptr_t) key; attr.value = (uintptr_t) value; attr.flags = flags; return ngx_bpf(BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr)); } int ngx_bpf_map_delete(int fd, const void *key) { union bpf_attr attr; ngx_memzero(&attr, sizeof(union bpf_attr)); attr.map_fd = fd; attr.key = (uintptr_t) key; return ngx_bpf(BPF_MAP_DELETE_ELEM, &attr, sizeof(attr)); } int ngx_bpf_map_lookup(int fd, const void *key, void *value) { union bpf_attr attr; ngx_memzero(&attr, sizeof(union bpf_attr)); attr.map_fd = fd; attr.key = (uintptr_t) key; attr.value = (uintptr_t) value; return ngx_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr)); }