libuv/src/unix/uv-eio.c
2011-08-31 00:24:07 -07:00

135 lines
4.0 KiB
C

/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
/* This file integrates the libuv event loop with the libeio thread pool */
#include "uv.h"
#include "eio.h"
#include <assert.h>
#include <stdio.h>
/* TODO remove me! */
static uv_loop_t* main_loop;
static void uv_eio_do_poll(uv_idle_t* watcher, int status) {
assert(watcher == &(watcher->loop->uv_eio_poller));
/* printf("uv_eio_poller\n"); */
if (eio_poll() != -1 && uv_is_active((uv_handle_t*) watcher)) {
/* printf("uv_eio_poller stop\n"); */
uv_idle_stop(watcher);
uv_unref(watcher->loop);
}
}
/* Called from the main thread. */
static void uv_eio_want_poll_notifier_cb(uv_async_t* watcher, int status) {
uv_loop_t* loop = watcher->loop;
assert(watcher == &loop->uv_eio_want_poll_notifier);
/* printf("want poll notifier\n"); */
if (eio_poll() == -1 && !uv_is_active((uv_handle_t*) &loop->uv_eio_poller)) {
/* printf("uv_eio_poller start\n"); */
uv_idle_start(&loop->uv_eio_poller, uv_eio_do_poll);
uv_ref(loop);
}
}
static void uv_eio_done_poll_notifier_cb(uv_async_t* watcher, int revents) {
uv_loop_t* loop = watcher->loop;
assert(watcher == &loop->uv_eio_done_poll_notifier);
/* printf("done poll notifier\n"); */
if (eio_poll() != -1 && uv_is_active((uv_handle_t*) &loop->uv_eio_poller)) {
/* printf("uv_eio_poller stop\n"); */
uv_idle_stop(&loop->uv_eio_poller);
uv_unref(loop);
}
}
/*
* uv_eio_want_poll() is called from the EIO thread pool each time an EIO
* request (that is, one of the node.fs.* functions) has completed.
*/
static void uv_eio_want_poll(void) {
/* Signal the main thread that eio_poll need to be processed. */
/*
* TODO need to select the correct uv_loop_t and async_send to
* uv_eio_want_poll_notifier.
*/
uv_async_send(&main_loop->uv_eio_want_poll_notifier);
}
static void uv_eio_done_poll(void) {
/*
* Signal the main thread that we should stop calling eio_poll().
* from the idle watcher.
*/
uv_async_send(&main_loop->uv_eio_done_poll_notifier);
}
void uv_eio_init(uv_loop_t* loop) {
if (loop->counters.eio_init == 0) {
loop->counters.eio_init++;
main_loop = loop;
uv_idle_init(loop, &loop->uv_eio_poller);
uv_idle_start(&loop->uv_eio_poller, uv_eio_do_poll);
loop->uv_eio_want_poll_notifier.data = loop;
uv_async_init(loop, &loop->uv_eio_want_poll_notifier,
uv_eio_want_poll_notifier_cb);
uv_unref(loop);
uv_async_init(loop, &loop->uv_eio_done_poll_notifier,
uv_eio_done_poll_notifier_cb);
uv_unref(loop);
eio_init(uv_eio_want_poll, uv_eio_done_poll);
/*
* Don't handle more than 10 reqs on each eio_poll(). This is to avoid
* race conditions. See Node's test/simple/test-eio-race.js
*/
eio_set_max_poll_reqs(10);
} else {
/*
* If this assertion breaks then Ryan hasn't implemented support for
* receiving thread pool requests back to multiple threads.
*/
assert(main_loop == loop);
}
}