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openmpi/opal/event/epoll.c
Tim Woodall dc0f3eef63 more corrections
This commit was SVN r7100.
2005-08-30 21:26:24 +00:00

344 строки
8.0 KiB
C

/*
* Copyright 2000-2003 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "ompi_config.h"
#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_RESOURCE_H
#include <sys/resource.h>
#endif
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#else
#include <sys/_time.h>
#endif
#include <sys/queue.h>
#include <sys/epoll.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <errno.h>
#include <err.h>
#ifdef USE_LOG
#include "log.h"
#else
#define LOG_DBG(x)
#define log_error warn
#endif
#include "event.h"
#include "evsignal.h"
#include "opal/threads/mutex.h"
extern struct opal_event_list opal_eventqueue;
extern volatile sig_atomic_t opal_evsignal_caught;
extern opal_mutex_t opal_event_lock;
/* due to limitations in the epoll interface, we need to keep track of
* all file descriptors outself.
*/
struct evepoll {
struct opal_event *evread;
struct opal_event *evwrite;
};
struct epollop {
struct evepoll *fds;
int nfds;
struct epoll_event *events;
int nevents;
int epfd;
sigset_t evsigmask;
} epollop;
static void *epoll_init (void);
static int epoll_add (void *, struct opal_event *);
static int epoll_del (void *, struct opal_event *);
static int epoll_recalc (void *, int);
static int epoll_dispatch (void *, struct timeval *);
struct opal_eventop opal_epollops = {
"epoll",
epoll_init,
epoll_add,
epoll_del,
epoll_recalc,
epoll_dispatch
};
#define NEVENT 32000
static void *
epoll_init(void)
{
int epfd, nfiles = NEVENT;
struct rlimit rl;
/* Disable epollueue when this environment variable is set */
if (getenv("EVENT_NOEPOLL"))
return (NULL);
memset(&epollop, 0, sizeof(epollop));
if (getrlimit(RLIMIT_NOFILE, &rl) == 0 &&
rl.rlim_cur != RLIM_INFINITY)
nfiles = rl.rlim_cur;
/* Initalize the kernel queue */
if ((epfd = epoll_create(nfiles)) == -1) {
log_error("epoll_create");
return (NULL);
}
epollop.epfd = epfd;
/* Initalize fields */
epollop.events = malloc(nfiles * sizeof(struct epoll_event));
if (epollop.events == NULL)
return (NULL);
epollop.nevents = nfiles;
epollop.fds = calloc(nfiles, sizeof(struct evepoll));
if (epollop.fds == NULL) {
free(epollop.events);
return (NULL);
}
epollop.nfds = nfiles;
opal_evsignal_init(&epollop.evsigmask);
return (&epollop);
}
static int
epoll_recalc(void *arg, int max)
{
struct epollop *epollop = arg;
if (max > epollop->nfds) {
struct evepoll *fds;
int nfds;
nfds = epollop->nfds;
while (nfds < max)
nfds <<= 1;
fds = realloc(epollop->fds, nfds * sizeof(struct evepoll));
if (fds == NULL) {
log_error("realloc");
return (-1);
}
epollop->fds = fds;
memset(fds + epollop->nfds, 0,
(nfds - epollop->nfds) * sizeof(struct evepoll));
epollop->nfds = nfds;
}
return (opal_evsignal_recalc(&epollop->evsigmask));
}
int
epoll_dispatch(void *arg, struct timeval *tv)
{
struct epollop *epollop = arg;
struct epoll_event *events = epollop->events;
struct evepoll *evep;
int i, res, timeout;
if (opal_evsignal_deliver(&epollop->evsigmask) == -1)
return (-1);
timeout = tv->tv_sec * 1000 + tv->tv_usec / 1000;
opal_mutex_unlock(&opal_event_lock);
res = epoll_wait(epollop->epfd, events, epollop->nevents, timeout);
opal_mutex_lock(&opal_event_lock);
if (opal_evsignal_recalc(&epollop->evsigmask) == -1)
return (-1);
if (res == -1) {
if (errno != EINTR) {
log_error("epoll_wait");
return (-1);
}
opal_evsignal_process();
return (0);
} else if (opal_evsignal_caught)
opal_evsignal_process();
LOG_DBG((LOG_MISC, 80, "%s: epoll_wait reports %d", __func__, res));
for (i = 0; i < res; i++) {
int which = 0;
int what = events[i].events;
struct opal_event *evread = NULL, *evwrite = NULL;
evep = (struct evepoll *)events[i].data.ptr;
if (what & EPOLLHUP)
what |= EPOLLIN | EPOLLOUT;
else if (what & EPOLLERR)
what |= EPOLLIN | EPOLLOUT;
if (what & EPOLLIN) {
evread = evep->evread;
which |= OPAL_EV_READ;
}
if (what & EPOLLOUT) {
evwrite = evep->evwrite;
which |= OPAL_EV_WRITE;
}
if (!which)
continue;
if (evread != NULL && !(evread->ev_events & OPAL_EV_PERSIST))
opal_event_del_i(evread);
if (evwrite != NULL && evwrite != evread &&
!(evwrite->ev_events & OPAL_EV_PERSIST))
opal_event_del_i(evwrite);
if (evread != NULL)
opal_event_active_i(evread, OPAL_EV_READ, 1);
if (evwrite != NULL)
opal_event_active_i(evwrite, OPAL_EV_WRITE, 1);
}
return (0);
}
static int
epoll_add(void *arg, struct opal_event *ev)
{
struct epollop *epollop = arg;
struct epoll_event epev;
struct evepoll *evep;
int fd, op, events;
if (ev->ev_events & OPAL_EV_SIGNAL)
return (opal_evsignal_add(&epollop->evsigmask, ev));
fd = ev->ev_fd;
if (fd >= epollop->nfds) {
/* Extent the file descriptor array as necessary */
if (epoll_recalc(epollop, fd) == -1)
return (-1);
}
evep = &epollop->fds[fd];
op = EPOLL_CTL_ADD;
events = 0;
if (evep->evread != NULL) {
events |= EPOLLIN;
op = EPOLL_CTL_MOD;
}
if (evep->evwrite != NULL) {
events |= EPOLLOUT;
op = EPOLL_CTL_MOD;
}
if (ev->ev_events & OPAL_EV_READ)
events |= EPOLLIN;
if (ev->ev_events & OPAL_EV_WRITE)
events |= EPOLLOUT;
epev.data.ptr = evep;
epev.events = events;
if (epoll_ctl(epollop->epfd, op, ev->ev_fd, &epev) == -1)
return (-1);
/* Update events responsible */
if (ev->ev_events & OPAL_EV_READ)
evep->evread = ev;
if (ev->ev_events & OPAL_EV_WRITE)
evep->evwrite = ev;
return (0);
}
static int
epoll_del(void *arg, struct opal_event *ev)
{
struct epollop *epollop = arg;
struct epoll_event epev;
struct evepoll *evep;
int fd, events, op;
int needwritedelete = 1, needreaddelete = 1;
if (ev->ev_events & OPAL_EV_SIGNAL)
return (opal_evsignal_del(&epollop->evsigmask, ev));
fd = ev->ev_fd;
if (fd >= epollop->nfds)
return (0);
evep = &epollop->fds[fd];
op = EPOLL_CTL_DEL;
events = 0;
if (ev->ev_events & OPAL_EV_READ)
events |= EPOLLIN;
if (ev->ev_events & OPAL_EV_WRITE)
events |= EPOLLOUT;
if ((events & (EPOLLIN|EPOLLOUT)) != (EPOLLIN|EPOLLOUT)) {
if ((events & EPOLLIN) && evep->evwrite != NULL) {
needwritedelete = 0;
events = EPOLLOUT;
op = EPOLL_CTL_MOD;
} else if ((events & EPOLLOUT) && evep->evread != NULL) {
needreaddelete = 0;
events = EPOLLIN;
op = EPOLL_CTL_MOD;
}
}
epev.events = events;
epev.data.ptr = evep;
if (epoll_ctl(epollop->epfd, op, fd, &epev) == -1)
return (-1);
if (needreaddelete)
evep->evread = NULL;
if (needwritedelete)
evep->evwrite = NULL;
return (0);
}