trunk/src/s_bsd_epoll.c

/*
 *  ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
 *
 *  Copyright (c) 2005-2018 ircd-hybrid development team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 *  USA
 */

/*! \file s_bsd_epoll.c
 * \brief Linux epoll() compatible network routines.
 * \version $Id$
 */

#include "stdinc.h"
#if USE_IOPOLL_MECHANISM == __IOPOLL_MECHANISM_EPOLL
#include "fdlist.h"
#include "ircd.h"
#include "s_bsd.h"
#include "log.h"
#include "memory.h"
#include <sys/epoll.h>

enum
{
  INITIAL_NEVENT =   16,
  MAXIMUM_NEVENT = 4096
};

struct epollop
{
  struct epoll_event *events;
  int nevents;
  int fd;
};

static struct epollop *epollop;


/*
 * comm_select_init
 *
 * This is a needed exported function which will be called to initialise
 * the network loop code.
 */
void
comm_select_init(void)
{
  int fd = epoll_create1(EPOLL_CLOEXEC);
  if (fd < 0)
  {
    ilog(LOG_TYPE_IRCD, "comm_select_init: couldn't open epoll fd: %s",
         strerror(errno));
    exit(EXIT_FAILURE); /* Whee! */
  }

  fd_open(fd, 0, "epoll file descriptor");

  epollop = xcalloc(sizeof(*epollop));
  epollop->fd = fd;
  epollop->nevents = INITIAL_NEVENT;
  epollop->events = xcalloc(epollop->nevents * sizeof(*epollop->events));
}

/*
 * comm_setselect
 *
 * This is a needed exported function which will be called to register
 * and deregister interest in a pending IO state for a given FD.
 */
void
comm_setselect(fde_t *F, unsigned int type, void (*handler)(fde_t *, void *),
               void *client_data, uintmax_t timeout)
{
  int new_events, op;
  struct epoll_event ep_event;

  assert(F->flags.open);

  if ((type & COMM_SELECT_READ))
  {
    F->read_handler = handler;
    F->read_data = client_data;
  }

  if ((type & COMM_SELECT_WRITE))
  {
    F->write_handler = handler;
    F->write_data = client_data;
  }

  new_events = (F->read_handler ? EPOLLIN : 0) |
    (F->write_handler ? EPOLLOUT : 0);

  if (timeout)
  {
    F->timeout = CurrentTime + (timeout / 1000);
    F->timeout_handler = handler;
    F->timeout_data = client_data;
  }

  if (new_events != F->evcache)
  {
    if (new_events == 0)
      op = EPOLL_CTL_DEL;
    else if (F->evcache == 0)
      op = EPOLL_CTL_ADD;
    else
      op = EPOLL_CTL_MOD;

    memset(&ep_event, 0, sizeof(ep_event));
    ep_event.events = F->evcache = new_events;
    ep_event.data.ptr = F;

    if (epoll_ctl(epollop->fd, op, F->fd, &ep_event))
    {
      ilog(LOG_TYPE_IRCD, "comm_setselect: epoll_ctl() failed: %s", strerror(errno));
      abort();
    }
  }
}

/*
 * comm_select()
 *
 * Called to do the new-style IO, courtesy of of squid (like most of this
 * new IO code). This routine handles the stuff we've hidden in
 * comm_setselect and fd_table[] and calls callbacks for IO ready
 * events.
 */
void
comm_select(void)
{
  int num;
  void (*hdl)(fde_t *, void *);

  num = epoll_wait(epollop->fd, epollop->events, epollop->nevents, SELECT_DELAY);
  assert(num <= epollop->nevents);

  set_time();

  if (num < 0)
  {
    const struct timespec req = { .tv_sec = 0, .tv_nsec = 50000000 };
    nanosleep(&req, NULL);  /* Avoid 99% CPU in comm_select */
    return;
  }

  for (int i = 0; i < num; ++i)
  {
    fde_t *F = epollop->events[i].data.ptr;

    if (F->flags.open == 0)
      continue;

    if ((epollop->events[i].events & (EPOLLIN | EPOLLHUP | EPOLLERR)))
    {
      if ((hdl = F->read_handler))
      {
        F->read_handler = NULL;
        hdl(F, F->read_data);

        if (F->flags.open == 0)
          continue;
      }
    }

    if ((epollop->events[i].events & (EPOLLOUT | EPOLLHUP | EPOLLERR)))
    {
      if ((hdl = F->write_handler))
      {
        F->write_handler = NULL;
        hdl(F, F->write_data);

        if (F->flags.open == 0)
          continue;
      }
    }

    comm_setselect(F, 0, NULL, NULL, 0);
  }

  if (num == epollop->nevents && epollop->nevents < MAXIMUM_NEVENT)
  {
    /*
     * We used all of the event space this time. We should be
     * ready for more events next time.
     */
    int new_nevents = epollop->nevents * 2;
    struct epoll_event *new_events = xrealloc(epollop->events, new_nevents * sizeof(*epollop->events));

    epollop->events = new_events;
    epollop->nevents = new_nevents;
  }
}
#endif
Revision:	8536
Committed:	Sun Apr 29 17:12:26 2018 UTC (7 years, 3 months ago) by michael
Content type:	text/x-csrc
File size:	4921 byte(s)
Log Message:	- s_bsd_epoll.c: remove syscall.h header include
#	Content
1	/*
2	* ircd-hybrid: an advanced, lightweight Internet Relay Chat Daemon (ircd)
3	*
4	* Copyright (c) 2005-2018 ircd-hybrid development team
5	*
6	* This program is free software; you can redistribute it and/or modify
7	* it under the terms of the GNU General Public License as published by
8	* the Free Software Foundation; either version 2 of the License, or
9	* (at your option) any later version.
10	*
11	* This program is distributed in the hope that it will be useful,
12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14	* GNU General Public License for more details.
15	*
16	* You should have received a copy of the GNU General Public License
17	* along with this program; if not, write to the Free Software
18	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
19	* USA
20	*/
21
22	/*! \file s_bsd_epoll.c
23	* \brief Linux epoll() compatible network routines.
24	* \version $Id$
25	*/
26
27	#include "stdinc.h"
28	#if USE_IOPOLL_MECHANISM == __IOPOLL_MECHANISM_EPOLL
29	#include "fdlist.h"
30	#include "ircd.h"
31	#include "s_bsd.h"
32	#include "log.h"
33	#include "memory.h"
34	#include <sys/epoll.h>
35
36	enum
37	{
38	INITIAL_NEVENT = 16,
39	MAXIMUM_NEVENT = 4096
40	};
41
42	struct epollop
43	{
44	struct epoll_event *events;
45	int nevents;
46	int fd;
47	};
48
49	static struct epollop *epollop;
50
51
52	/*
53	* comm_select_init
54	*
55	* This is a needed exported function which will be called to initialise
56	* the network loop code.
57	*/
58	void
59	comm_select_init(void)
60	{
61	int fd = epoll_create1(EPOLL_CLOEXEC);
62	if (fd < 0)
63	{
64	ilog(LOG_TYPE_IRCD, "comm_select_init: couldn't open epoll fd: %s",
65	strerror(errno));
66	exit(EXIT_FAILURE); /* Whee! */
67	}
68
69	fd_open(fd, 0, "epoll file descriptor");
70
71	epollop = xcalloc(sizeof(*epollop));
72	epollop->fd = fd;
73	epollop->nevents = INITIAL_NEVENT;
74	epollop->events = xcalloc(epollop->nevents * sizeof(*epollop->events));
75	}
76
77	/*
78	* comm_setselect
79	*
80	* This is a needed exported function which will be called to register
81	* and deregister interest in a pending IO state for a given FD.
82	*/
83	void
84	comm_setselect(fde_t F, unsigned int type, void (handler)(fde_t , void ),
85	void *client_data, uintmax_t timeout)
86	{
87	int new_events, op;
88	struct epoll_event ep_event;
89
90	assert(F->flags.open);
91
92	if ((type & COMM_SELECT_READ))
93	{
94	F->read_handler = handler;
95	F->read_data = client_data;
96	}
97
98	if ((type & COMM_SELECT_WRITE))
99	{
100	F->write_handler = handler;
101	F->write_data = client_data;
102	}
103
104	new_events = (F->read_handler ? EPOLLIN : 0) \|
105	(F->write_handler ? EPOLLOUT : 0);
106
107	if (timeout)
108	{
109	F->timeout = CurrentTime + (timeout / 1000);
110	F->timeout_handler = handler;
111	F->timeout_data = client_data;
112	}
113
114	if (new_events != F->evcache)
115	{
116	if (new_events == 0)
117	op = EPOLL_CTL_DEL;
118	else if (F->evcache == 0)
119	op = EPOLL_CTL_ADD;
120	else
121	op = EPOLL_CTL_MOD;
122
123	memset(&ep_event, 0, sizeof(ep_event));
124	ep_event.events = F->evcache = new_events;
125	ep_event.data.ptr = F;
126
127	if (epoll_ctl(epollop->fd, op, F->fd, &ep_event))
128	{
129	ilog(LOG_TYPE_IRCD, "comm_setselect: epoll_ctl() failed: %s", strerror(errno));
130	abort();
131	}
132	}
133	}
134
135	/*
136	* comm_select()
137	*
138	* Called to do the new-style IO, courtesy of of squid (like most of this
139	* new IO code). This routine handles the stuff we've hidden in
140	* comm_setselect and fd_table[] and calls callbacks for IO ready
141	* events.
142	*/
143	void
144	comm_select(void)
145	{
146	int num;
147	void (hdl)(fde_t , void *);
148
149	num = epoll_wait(epollop->fd, epollop->events, epollop->nevents, SELECT_DELAY);
150	assert(num <= epollop->nevents);
151
152	set_time();
153
154	if (num < 0)
155	{
156	const struct timespec req = { .tv_sec = 0, .tv_nsec = 50000000 };
157	nanosleep(&req, NULL); /* Avoid 99% CPU in comm_select */
158	return;
159	}
160
161	for (int i = 0; i < num; ++i)
162	{
163	fde_t *F = epollop->events[i].data.ptr;
164
165	if (F->flags.open == 0)
166	continue;
167
168	if ((epollop->events[i].events & (EPOLLIN \| EPOLLHUP \| EPOLLERR)))
169	{
170	if ((hdl = F->read_handler))
171	{
172	F->read_handler = NULL;
173	hdl(F, F->read_data);
174
175	if (F->flags.open == 0)
176	continue;
177	}
178	}
179
180	if ((epollop->events[i].events & (EPOLLOUT \| EPOLLHUP \| EPOLLERR)))
181	{
182	if ((hdl = F->write_handler))
183	{
184	F->write_handler = NULL;
185	hdl(F, F->write_data);
186
187	if (F->flags.open == 0)
188	continue;
189	}
190	}
191
192	comm_setselect(F, 0, NULL, NULL, 0);
193	}
194
195	if (num == epollop->nevents && epollop->nevents < MAXIMUM_NEVENT)
196	{
197	/*
198	* We used all of the event space this time. We should be
199	* ready for more events next time.
200	*/
201	int new_nevents = epollop->nevents * 2;
202	struct epoll_event new_events = xrealloc(epollop->events, new_nevents sizeof(*epollop->events));
203
204	epollop->events = new_events;
205	epollop->nevents = new_nevents;
206	}
207	}
208	#endif