Mercurial > hg > nginx
view src/os/unix/ngx_file_aio_read.c @ 7441:8acaa1161783
Stream: do not split datagrams when limiting proxy rate.
Previously, when using proxy_upload_rate and proxy_download_rate, the buffer
size for reading from a socket could be reduced as a result of rate limiting.
For connection-oriented protocols this behavior is normal since unread data will
normally be read at the next iteration. But for datagram-oriented protocols
this is not the case, and unread part of the datagram is lost.
Now buffer size is not limited for datagrams. Rate limiting still works in this
case by delaying the next reading event.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Thu, 27 Dec 2018 19:37:34 +0300 |
parents | f01ab2dbcfdc |
children | 7f035fd1ec7b |
line wrap: on
line source
/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> /* * FreeBSD file AIO features and quirks: * * if an asked data are already in VM cache, then aio_error() returns 0, * and the data are already copied in buffer; * * aio_read() preread in VM cache as minimum 16K (probably BKVASIZE); * the first AIO preload may be up to 128K; * * aio_read/aio_error() may return EINPROGRESS for just written data; * * kqueue EVFILT_AIO filter is level triggered only: an event repeats * until aio_return() will be called; * * aio_cancel() cannot cancel file AIO: it returns AIO_NOTCANCELED always. */ extern int ngx_kqueue; static ssize_t ngx_file_aio_result(ngx_file_t *file, ngx_event_aio_t *aio, ngx_event_t *ev); static void ngx_file_aio_event_handler(ngx_event_t *ev); ngx_int_t ngx_file_aio_init(ngx_file_t *file, ngx_pool_t *pool) { ngx_event_aio_t *aio; aio = ngx_pcalloc(pool, sizeof(ngx_event_aio_t)); if (aio == NULL) { return NGX_ERROR; } aio->file = file; aio->fd = file->fd; aio->event.data = aio; aio->event.ready = 1; aio->event.log = file->log; file->aio = aio; return NGX_OK; } ssize_t ngx_file_aio_read(ngx_file_t *file, u_char *buf, size_t size, off_t offset, ngx_pool_t *pool) { int n; ngx_event_t *ev; ngx_event_aio_t *aio; if (!ngx_file_aio) { return ngx_read_file(file, buf, size, offset); } if (file->aio == NULL && ngx_file_aio_init(file, pool) != NGX_OK) { return NGX_ERROR; } aio = file->aio; ev = &aio->event; if (!ev->ready) { ngx_log_error(NGX_LOG_ALERT, file->log, 0, "second aio post for \"%V\"", &file->name); return NGX_AGAIN; } ngx_log_debug4(NGX_LOG_DEBUG_CORE, file->log, 0, "aio complete:%d @%O:%uz %V", ev->complete, offset, size, &file->name); if (ev->complete) { ev->complete = 0; ngx_set_errno(aio->err); if (aio->err == 0) { return aio->nbytes; } ngx_log_error(NGX_LOG_CRIT, file->log, ngx_errno, "aio read \"%s\" failed", file->name.data); return NGX_ERROR; } ngx_memzero(&aio->aiocb, sizeof(struct aiocb)); aio->aiocb.aio_fildes = file->fd; aio->aiocb.aio_offset = offset; aio->aiocb.aio_buf = buf; aio->aiocb.aio_nbytes = size; #if (NGX_HAVE_KQUEUE) aio->aiocb.aio_sigevent.sigev_notify_kqueue = ngx_kqueue; aio->aiocb.aio_sigevent.sigev_notify = SIGEV_KEVENT; aio->aiocb.aio_sigevent.sigev_value.sigval_ptr = ev; #endif ev->handler = ngx_file_aio_event_handler; n = aio_read(&aio->aiocb); if (n == -1) { n = ngx_errno; if (n == NGX_EAGAIN) { return ngx_read_file(file, buf, size, offset); } ngx_log_error(NGX_LOG_CRIT, file->log, n, "aio_read(\"%V\") failed", &file->name); if (n == NGX_ENOSYS) { ngx_file_aio = 0; return ngx_read_file(file, buf, size, offset); } return NGX_ERROR; } ngx_log_debug2(NGX_LOG_DEBUG_CORE, file->log, 0, "aio_read: fd:%d %d", file->fd, n); ev->active = 1; ev->ready = 0; ev->complete = 0; return ngx_file_aio_result(aio->file, aio, ev); } static ssize_t ngx_file_aio_result(ngx_file_t *file, ngx_event_aio_t *aio, ngx_event_t *ev) { int n; ngx_err_t err; n = aio_error(&aio->aiocb); ngx_log_debug2(NGX_LOG_DEBUG_CORE, file->log, 0, "aio_error: fd:%d %d", file->fd, n); if (n == -1) { err = ngx_errno; aio->err = err; ngx_log_error(NGX_LOG_ALERT, file->log, err, "aio_error(\"%V\") failed", &file->name); return NGX_ERROR; } if (n == NGX_EINPROGRESS) { if (ev->ready) { ev->ready = 0; ngx_log_error(NGX_LOG_ALERT, file->log, n, "aio_read(\"%V\") still in progress", &file->name); } return NGX_AGAIN; } n = aio_return(&aio->aiocb); if (n == -1) { err = ngx_errno; aio->err = err; ev->ready = 1; ngx_log_error(NGX_LOG_CRIT, file->log, err, "aio_return(\"%V\") failed", &file->name); return NGX_ERROR; } aio->err = 0; aio->nbytes = n; ev->ready = 1; ev->active = 0; ngx_log_debug2(NGX_LOG_DEBUG_CORE, file->log, 0, "aio_return: fd:%d %d", file->fd, n); return n; } static void ngx_file_aio_event_handler(ngx_event_t *ev) { ngx_event_aio_t *aio; aio = ev->data; ngx_log_debug2(NGX_LOG_DEBUG_CORE, ev->log, 0, "aio event handler fd:%d %V", aio->fd, &aio->file->name); if (ngx_file_aio_result(aio->file, aio, ev) != NGX_AGAIN) { aio->handler(ev); } }