epoll.cpp 5.38 KB
Newer Older
Martin Sustrik's avatar
Martin Sustrik committed
1
/*
2
    Copyright (c) 2007-2010 iMatix Corporation
Martin Sustrik's avatar
Martin Sustrik committed
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

    This file is part of 0MQ.

    0MQ is free software; you can redistribute it and/or modify it under
    the terms of the Lesser GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    0MQ is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    Lesser GNU General Public License for more details.

    You should have received a copy of the Lesser GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "platform.hpp"

Martin Sustrik's avatar
Martin Sustrik committed
22
#ifdef ZMQ_HAVE_LINUX
Martin Sustrik's avatar
Martin Sustrik committed
23 24 25 26 27 28

#include <sys/epoll.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <algorithm>
29
#include <new>
Martin Sustrik's avatar
Martin Sustrik committed
30 31 32 33 34 35

#include "epoll.hpp"
#include "err.hpp"
#include "config.hpp"
#include "i_poll_events.hpp"

Martin Sustrik's avatar
Martin Sustrik committed
36
zmq::epoll_t::epoll_t () :
Martin Sustrik's avatar
Martin Sustrik committed
37 38 39 40 41 42
    stopping (false)
{
    epoll_fd = epoll_create (1);
    errno_assert (epoll_fd != -1);
}

Martin Sustrik's avatar
Martin Sustrik committed
43
zmq::epoll_t::~epoll_t ()
Martin Sustrik's avatar
Martin Sustrik committed
44
{
45 46 47
    //  Wait till the worker thread exits.
    worker.stop ();

48 49
    //  Make sure there are no fds registered on shutdown.
    zmq_assert (load.get () == 0);
Martin Sustrik's avatar
Martin Sustrik committed
50

51
    close (epoll_fd);
Martin Sustrik's avatar
Martin Sustrik committed
52 53 54 55
    for (retired_t::iterator it = retired.begin (); it != retired.end (); it ++)
        delete *it;
}

56
zmq::epoll_t::handle_t zmq::epoll_t::add_fd (fd_t fd_, i_poll_events *events_)
Martin Sustrik's avatar
Martin Sustrik committed
57
{
58
    poll_entry_t *pe = new (std::nothrow) poll_entry_t;
Martin Sustrik's avatar
Martin Sustrik committed
59
    zmq_assert (pe != NULL);
Martin Sustrik's avatar
Martin Sustrik committed
60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75

    //  The memset is not actually needed. It's here to prevent debugging
    //  tools to complain about using uninitialised memory.
    memset (pe, 0, sizeof (poll_entry_t));

    pe->fd = fd_;
    pe->ev.events = 0;
    pe->ev.data.ptr = pe;
    pe->events = events_;

    int rc = epoll_ctl (epoll_fd, EPOLL_CTL_ADD, fd_, &pe->ev);
    errno_assert (rc != -1);

    //  Increase the load metric of the thread.
    load.add (1);

76
    return pe;
Martin Sustrik's avatar
Martin Sustrik committed
77 78
}

Martin Sustrik's avatar
Martin Sustrik committed
79
void zmq::epoll_t::rm_fd (handle_t handle_)
Martin Sustrik's avatar
Martin Sustrik committed
80
{
81
    poll_entry_t *pe = (poll_entry_t*) handle_;
Martin Sustrik's avatar
Martin Sustrik committed
82 83 84 85 86 87 88 89 90
    int rc = epoll_ctl (epoll_fd, EPOLL_CTL_DEL, pe->fd, &pe->ev);
    errno_assert (rc != -1);
    pe->fd = retired_fd;
    retired.push_back (pe);

    //  Decrease the load metric of the thread.
    load.sub (1);
}

Martin Sustrik's avatar
Martin Sustrik committed
91
void zmq::epoll_t::set_pollin (handle_t handle_)
Martin Sustrik's avatar
Martin Sustrik committed
92
{
93
    poll_entry_t *pe = (poll_entry_t*) handle_;
Martin Sustrik's avatar
Martin Sustrik committed
94 95 96 97 98
    pe->ev.events |= EPOLLIN;
    int rc = epoll_ctl (epoll_fd, EPOLL_CTL_MOD, pe->fd, &pe->ev);
    errno_assert (rc != -1);
}

Martin Sustrik's avatar
Martin Sustrik committed
99
void zmq::epoll_t::reset_pollin (handle_t handle_)
Martin Sustrik's avatar
Martin Sustrik committed
100
{
101
    poll_entry_t *pe = (poll_entry_t*) handle_;
Martin Sustrik's avatar
Martin Sustrik committed
102 103 104 105 106
    pe->ev.events &= ~((short) EPOLLIN);
    int rc = epoll_ctl (epoll_fd, EPOLL_CTL_MOD, pe->fd, &pe->ev);
    errno_assert (rc != -1);
}

Martin Sustrik's avatar
Martin Sustrik committed
107
void zmq::epoll_t::set_pollout (handle_t handle_)
Martin Sustrik's avatar
Martin Sustrik committed
108
{
109
    poll_entry_t *pe = (poll_entry_t*) handle_;
Martin Sustrik's avatar
Martin Sustrik committed
110 111 112 113 114
    pe->ev.events |= EPOLLOUT;
    int rc = epoll_ctl (epoll_fd, EPOLL_CTL_MOD, pe->fd, &pe->ev);
    errno_assert (rc != -1);
}

Martin Sustrik's avatar
Martin Sustrik committed
115
void zmq::epoll_t::reset_pollout (handle_t handle_)
Martin Sustrik's avatar
Martin Sustrik committed
116
{
117
    poll_entry_t *pe = (poll_entry_t*) handle_;
Martin Sustrik's avatar
Martin Sustrik committed
118 119 120 121 122
    pe->ev.events &= ~((short) EPOLLOUT);
    int rc = epoll_ctl (epoll_fd, EPOLL_CTL_MOD, pe->fd, &pe->ev);
    errno_assert (rc != -1);
}

Martin Sustrik's avatar
Martin Sustrik committed
123
void zmq::epoll_t::add_timer (i_poll_events *events_)
Martin Sustrik's avatar
Martin Sustrik committed
124 125 126 127
{
     timers.push_back (events_);
}

Martin Sustrik's avatar
Martin Sustrik committed
128
void zmq::epoll_t::cancel_timer (i_poll_events *events_)
Martin Sustrik's avatar
Martin Sustrik committed
129 130 131 132 133 134 135
{
    timers_t::iterator it = std::find (timers.begin (), timers.end (), events_);
    if (it == timers.end ())
        return;
    timers.erase (it);
}

Martin Sustrik's avatar
Martin Sustrik committed
136
int zmq::epoll_t::get_load ()
Martin Sustrik's avatar
Martin Sustrik committed
137 138 139 140
{
    return load.get ();
}

Martin Sustrik's avatar
Martin Sustrik committed
141
void zmq::epoll_t::start ()
Martin Sustrik's avatar
Martin Sustrik committed
142 143 144 145
{
    worker.start (worker_routine, this);
}

Martin Sustrik's avatar
Martin Sustrik committed
146
void zmq::epoll_t::stop ()
Martin Sustrik's avatar
Martin Sustrik committed
147 148 149 150
{
    stopping = true;
}

Martin Sustrik's avatar
Martin Sustrik committed
151
void zmq::epoll_t::loop ()
Martin Sustrik's avatar
Martin Sustrik committed
152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207
{
    epoll_event ev_buf [max_io_events];

    while (!stopping) {

        //  Wait for events.
        int n;
        while (true) {
            n = epoll_wait (epoll_fd, &ev_buf [0], max_io_events,
                timers.empty () ? -1 : max_timer_period);
            if (!(n == -1 && errno == EINTR)) {
                errno_assert (n != -1);
                break;
            }
        }

        //  Handle timer.
        if (!n) {

            //  Use local list of timers as timer handlers may fill new timers
            //  into the original array.
            timers_t t;
            std::swap (timers, t);

            //  Trigger all the timers.
            for (timers_t::iterator it = t.begin (); it != t.end (); it ++)
                (*it)->timer_event ();

            continue;
        }

        for (int i = 0; i < n; i ++) {
            poll_entry_t *pe = ((poll_entry_t*) ev_buf [i].data.ptr);

            if (pe->fd == retired_fd)
                continue;
            if (ev_buf [i].events & (EPOLLERR | EPOLLHUP))
                pe->events->in_event ();
            if (pe->fd == retired_fd)
               continue;
            if (ev_buf [i].events & EPOLLOUT)
                pe->events->out_event ();
            if (pe->fd == retired_fd)
                continue;
            if (ev_buf [i].events & EPOLLIN)
                pe->events->in_event ();
        }

        //  Destroy retired event sources.
        for (retired_t::iterator it = retired.begin (); it != retired.end ();
              it ++)
            delete *it;
        retired.clear ();
    }
}

Martin Sustrik's avatar
Martin Sustrik committed
208
void zmq::epoll_t::worker_routine (void *arg_)
Martin Sustrik's avatar
Martin Sustrik committed
209 210 211 212 213
{
    ((epoll_t*) arg_)->loop ();
}

#endif