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/*
* Copyright (C) Igor Sysoev
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_event.h>
#if (NGX_TEST_BUILD_EPOLL)
/* epoll declarations */
#define EPOLLIN 0x001
#define EPOLLPRI 0x002
#define EPOLLOUT 0x004
#define EPOLLRDNORM 0x040
#define EPOLLRDBAND 0x080
#define EPOLLWRNORM 0x100
#define EPOLLWRBAND 0x200
#define EPOLLMSG 0x400
#define EPOLLERR 0x008
#define EPOLLHUP 0x010
#define EPOLLET 0x80000000
#define EPOLLONESHOT 0x40000000
#define EPOLL_CTL_ADD 1
#define EPOLL_CTL_DEL 2
#define EPOLL_CTL_MOD 3
typedef union epoll_data {
void *ptr;
int fd;
uint32_t u32;
uint64_t u64;
} epoll_data_t;
struct epoll_event {
uint32_t events;
epoll_data_t data;
};
int epoll_create(int size);
int epoll_ctl(int epfd, int op, int fd, struct epoll_event *event);
int epoll_wait(int epfd, struct epoll_event *events, int nevents, int timeout);
int epoll_create(int size)
{
return -1;
}
int epoll_ctl(int epfd, int op, int fd, struct epoll_event *event)
{
return -1;
}
int epoll_wait(int epfd, struct epoll_event *events, int nevents, int timeout)
{
return -1;
}
#endif
typedef struct {
u_int events;
} ngx_epoll_conf_t;
static int ngx_epoll_init(ngx_cycle_t *cycle);
static void ngx_epoll_done(ngx_cycle_t *cycle);
static int ngx_epoll_add_event(ngx_event_t *ev, int event, u_int flags);
static int ngx_epoll_del_event(ngx_event_t *ev, int event, u_int flags);
static int ngx_epoll_add_connection(ngx_connection_t *c);
static int ngx_epoll_del_connection(ngx_connection_t *c, u_int flags);
static int ngx_epoll_process_events(ngx_cycle_t *cycle);
static void *ngx_epoll_create_conf(ngx_cycle_t *cycle);
static char *ngx_epoll_init_conf(ngx_cycle_t *cycle, void *conf);
static int ep = -1;
static struct epoll_event *event_list;
static u_int nevents;
static ngx_str_t epoll_name = ngx_string("epoll");
static ngx_command_t ngx_epoll_commands[] = {
{ngx_string("epoll_events"),
NGX_EVENT_CONF|NGX_CONF_TAKE1,
ngx_conf_set_num_slot,
0,
offsetof(ngx_epoll_conf_t, events),
NULL},
ngx_null_command
};
ngx_event_module_t ngx_epoll_module_ctx = {
&epoll_name,
ngx_epoll_create_conf, /* create configuration */
ngx_epoll_init_conf, /* init configuration */
{
ngx_epoll_add_event, /* add an event */
ngx_epoll_del_event, /* delete an event */
ngx_epoll_add_event, /* enable an event */
ngx_epoll_del_event, /* disable an event */
ngx_epoll_add_connection, /* add an connection */
ngx_epoll_del_connection, /* delete an connection */
NULL, /* process the changes */
ngx_epoll_process_events, /* process the events */
ngx_epoll_init, /* init the events */
ngx_epoll_done, /* done the events */
}
};
ngx_module_t ngx_epoll_module = {
NGX_MODULE,
&ngx_epoll_module_ctx, /* module context */
ngx_epoll_commands, /* module directives */
NGX_EVENT_MODULE, /* module type */
NULL, /* init module */
NULL /* init process */
};
static int ngx_epoll_init(ngx_cycle_t *cycle)
{
size_t n;
ngx_event_conf_t *ecf;
ngx_epoll_conf_t *epcf;
ecf = ngx_event_get_conf(cycle->conf_ctx, ngx_event_core_module);
epcf = ngx_event_get_conf(cycle->conf_ctx, ngx_epoll_module);
if (ep == -1) {
ep = epoll_create(ecf->connections / 2);
if (ep == -1) {
ngx_log_error(NGX_LOG_EMERG, cycle->log, ngx_errno,
"epoll_create() failed");
return NGX_ERROR;
}
}
if (nevents < epcf->events) {
if (event_list) {
ngx_free(event_list);
}
event_list = ngx_alloc(sizeof(struct epoll_event) * epcf->events,
cycle->log);
if (event_list == NULL) {
return NGX_ERROR;
}
}
nevents = epcf->events;
ngx_io = ngx_os_io;
ngx_event_actions = ngx_epoll_module_ctx.actions;
#if (NGX_HAVE_CLEAR_EVENT)
ngx_event_flags = NGX_USE_CLEAR_EVENT
#else
ngx_event_flags = NGX_USE_LEVEL_EVENT
#endif
|NGX_USE_GREEDY_EVENT
|NGX_USE_EPOLL_EVENT;
return NGX_OK;
}
static void ngx_epoll_done(ngx_cycle_t *cycle)
{
if (close(ep) == -1) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, ngx_errno,
"epoll close() failed");
}
ep = -1;
ngx_free(event_list);
event_list = NULL;
nevents = 0;
}
static int ngx_epoll_add_event(ngx_event_t *ev, int event, u_int flags)
{
int op, prev;
ngx_event_t *e;
ngx_connection_t *c;
struct epoll_event ee;
c = ev->data;
if (event == NGX_READ_EVENT) {
e = c->write;
prev = EPOLLOUT;
#if (NGX_READ_EVENT != EPOLLIN)
event = EPOLLIN;
#endif
} else {
e = c->read;
prev = EPOLLIN;
#if (NGX_WRITE_EVENT != EPOLLOUT)
event = EPOLLOUT;
#endif
}
if (e->active) {
op = EPOLL_CTL_MOD;
event |= prev;
} else {
op = EPOLL_CTL_ADD;
}
ee.events = event | flags;
ee.data.ptr = (void *) ((uintptr_t) c | ev->instance);
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0,
"epoll add event: fd:%d op:%d ev:%08XD",
c->fd, op, ee.events);
if (epoll_ctl(ep, op, c->fd, &ee) == -1) {
ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno,
"epoll_ctl(%d, %d) failed", op, c->fd);
return NGX_ERROR;
}
ev->active = 1;
#if 0
ev->oneshot = (flags & NGX_ONESHOT_EVENT) ? 1 : 0;
#endif
return NGX_OK;
}
static int ngx_epoll_del_event(ngx_event_t *ev, int event, u_int flags)
{
int op, prev;
ngx_event_t *e;
ngx_connection_t *c;
struct epoll_event ee;
/*
* when the file descriptor is closed the epoll automatically deletes
* it from its queue so we do not need to delete explicity the event
* before the closing the file descriptor
*/
if (flags & NGX_CLOSE_EVENT) {
ev->active = 0;
return NGX_OK;
}
c = ev->data;
if (event == NGX_READ_EVENT) {
e = c->write;
prev = EPOLLOUT;
} else {
e = c->read;
prev = EPOLLIN;
}
if (e->active) {
op = EPOLL_CTL_MOD;
ee.events = prev | flags;
ee.data.ptr = (void *) ((uintptr_t) c | ev->instance);
} else {
op = EPOLL_CTL_DEL;
ee.events = 0;
ee.data.ptr = NULL;
}
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, ev->log, 0,
"epoll del event: fd:%d op:%d ev:%08XD",
c->fd, op, ee.events);
if (epoll_ctl(ep, op, c->fd, &ee) == -1) {
ngx_log_error(NGX_LOG_ALERT, ev->log, ngx_errno,
"epoll_ctl(%d, %d) failed", op, c->fd);
return NGX_ERROR;
}
ev->active = 0;
return NGX_OK;
}
static int ngx_epoll_add_connection(ngx_connection_t *c)
{
struct epoll_event ee;
ee.events = EPOLLIN|EPOLLOUT|EPOLLET;
ee.data.ptr = (void *) ((uintptr_t) c | c->read->instance);
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, c->log, 0,
"epoll add connection: fd:%d ev:%08XD", c->fd, ee.events);
if (epoll_ctl(ep, EPOLL_CTL_ADD, c->fd, &ee) == -1) {
ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno,
"epoll_ctl(EPOLL_CTL_ADD, %d) failed", c->fd);
return NGX_ERROR;
}
c->read->active = 1;
c->write->active = 1;
return NGX_OK;
}
static int ngx_epoll_del_connection(ngx_connection_t *c, u_int flags)
{
int op;
struct epoll_event ee;
/*
* when the file descriptor is closed the epoll automatically deletes
* it from its queue so we do not need to delete explicity the event
* before the closing the file descriptor
*/
if (flags & NGX_CLOSE_EVENT) {
c->read->active = 0;
c->write->active = 0;
return NGX_OK;
}
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, c->log, 0,
"epoll del connection: fd:%d", c->fd);
op = EPOLL_CTL_DEL;
ee.events = 0;
ee.data.ptr = NULL;
if (epoll_ctl(ep, op, c->fd, &ee) == -1) {
ngx_log_error(NGX_LOG_ALERT, c->log, ngx_errno,
"epoll_ctl(%d, %d) failed", op, c->fd);
return NGX_ERROR;
}
c->read->active = 0;
c->write->active = 0;
return NGX_OK;
}
int ngx_epoll_process_events(ngx_cycle_t *cycle)
{
int events;
size_t n;
ngx_int_t instance, i;
ngx_uint_t lock, accept_lock, expire;
ngx_err_t err;
ngx_log_t *log;
ngx_msec_t timer;
ngx_event_t *rev, *wev;
struct timeval tv;
ngx_connection_t *c;
ngx_epoch_msec_t delta;
for ( ;; ) {
timer = ngx_event_find_timer();
#if (NGX_THREADS)
if (timer == NGX_TIMER_ERROR) {
return NGX_ERROR;
}
if (timer == NGX_TIMER_INFINITE || timer > 500) {
timer = 500;
break;
}
#endif
if (timer != 0) {
break;
}
ngx_log_debug0(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"epoll expired timer");
ngx_event_expire_timers((ngx_msec_t)
(ngx_elapsed_msec - ngx_old_elapsed_msec));
if (ngx_posted_events && ngx_threaded) {
ngx_wakeup_worker_thread(cycle);
}
}
/* NGX_TIMER_INFINITE == INFTIM */
if (timer == NGX_TIMER_INFINITE) {
expire = 0;
} else {
expire = 1;
}
ngx_old_elapsed_msec = ngx_elapsed_msec;
accept_lock = 0;
if (ngx_accept_mutex) {
if (ngx_accept_disabled > 0) {
ngx_accept_disabled--;
} else {
if (ngx_trylock_accept_mutex(cycle) == NGX_ERROR) {
return NGX_ERROR;
}
if (ngx_accept_mutex_held) {
accept_lock = 1;
} else if (timer == NGX_TIMER_INFINITE
|| timer > ngx_accept_mutex_delay)
{
timer = ngx_accept_mutex_delay;
expire = 0;
}
}
}
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"epoll timer: %d", timer);
events = epoll_wait(ep, event_list, nevents, timer);
if (events == -1) {
err = ngx_errno;
} else {
err = 0;
}
ngx_gettimeofday(&tv);
ngx_time_update(tv.tv_sec);
delta = ngx_elapsed_msec;
ngx_elapsed_msec = (ngx_epoch_msec_t) tv.tv_sec * 1000
+ tv.tv_usec / 1000 - ngx_start_msec;
if (timer != NGX_TIMER_INFINITE) {
delta = ngx_elapsed_msec - delta;
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"epoll timer: %d, delta: %d", timer, (int) delta);
} else {
if (events == 0) {
ngx_log_error(NGX_LOG_ALERT, cycle->log, 0,
"epoll_wait() returned no events without timeout");
ngx_accept_mutex_unlock();
return NGX_ERROR;
}
}
if (err) {
ngx_log_error((err == NGX_EINTR) ? NGX_LOG_INFO : NGX_LOG_ALERT,
cycle->log, err, "epoll_wait() failed");
ngx_accept_mutex_unlock();
return NGX_ERROR;
}
if (events > 0) {
if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_ERROR) {
ngx_accept_mutex_unlock();
return NGX_ERROR;
}
lock = 1;
} else {
lock =0;
}
log = cycle->log;
for (i = 0; i < events; i++) {
c = event_list[i].data.ptr;
instance = (uintptr_t) c & 1;
c = (ngx_connection_t *) ((uintptr_t) c & (uintptr_t) ~1);
rev = c->read;
if (c->fd == -1 || rev->instance != instance) {
/*
* the stale event from a file descriptor
* that was just closed in this iteration
*/
ngx_log_debug1(NGX_LOG_DEBUG_EVENT, cycle->log, 0,
"epoll: stale event %p", c);
continue;
}
#if (NGX_DEBUG0)
log = c->log ? c->log : cycle->log;
#endif
ngx_log_debug3(NGX_LOG_DEBUG_EVENT, log, 0,
"epoll: fd:%d ev:%04XD d:%p",
c->fd, event_list[i].events, event_list[i].data);
if (event_list[i].events & (EPOLLERR|EPOLLHUP)) {
ngx_log_debug2(NGX_LOG_DEBUG_EVENT, log, 0,
"epoll_wait() error on fd:%d ev:%04XD",
c->fd, event_list[i].events);
}
if (event_list[i].events & ~(EPOLLIN|EPOLLOUT|EPOLLERR|EPOLLHUP)) {
ngx_log_error(NGX_LOG_ALERT, log, 0,
"strange epoll_wait() events fd:%d ev:%04XD",
c->fd, event_list[i].events);
}
wev = c->write;
if ((event_list[i].events & (EPOLLOUT|EPOLLERR|EPOLLHUP))
&& wev->active)
{
if (ngx_threaded) {
wev->posted_ready = 1;
ngx_post_event(wev);
} else {
wev->ready = 1;
if (!ngx_accept_mutex_held) {
wev->event_handler(wev);
} else {
ngx_post_event(wev);
}
}
}
/*
* EPOLLIN must be handled after EPOLLOUT because we use
* the optimization to avoid the unnecessary mutex locking/unlocking
* if the accept event is the last one.
*/
if ((event_list[i].events & (EPOLLIN|EPOLLERR|EPOLLHUP))
&& rev->active)
{
if (ngx_threaded && !rev->accept) {
rev->posted_ready = 1;
ngx_post_event(rev);
continue;
}
rev->ready = 1;
if (!ngx_threaded && !ngx_accept_mutex_held) {
rev->event_handler(rev);
} else if (!rev->accept) {
ngx_post_event(rev);
} else if (ngx_accept_disabled <= 0) {
ngx_mutex_unlock(ngx_posted_events_mutex);
rev->event_handler(rev);
if (ngx_accept_disabled > 0) {
ngx_accept_mutex_unlock();
accept_lock = 0;
}
if (i + 1 == events) {
lock = 0;
break;
}
if (ngx_mutex_lock(ngx_posted_events_mutex) == NGX_ERROR) {
if (accept_lock) {
ngx_accept_mutex_unlock();
}
return NGX_ERROR;
}
}
}
}
if (accept_lock) {
ngx_accept_mutex_unlock();
}
if (lock) {
ngx_mutex_unlock(ngx_posted_events_mutex);
}
if (expire && delta) {
ngx_event_expire_timers((ngx_msec_t) delta);
}
if (ngx_posted_events) {
if (ngx_threaded) {
ngx_wakeup_worker_thread(cycle);
} else {
ngx_event_process_posted(cycle);
}
}
return NGX_OK;
}
static void *ngx_epoll_create_conf(ngx_cycle_t *cycle)
{
ngx_epoll_conf_t *epcf;
ngx_test_null(epcf, ngx_palloc(cycle->pool, sizeof(ngx_epoll_conf_t)),
NGX_CONF_ERROR);
epcf->events = NGX_CONF_UNSET;
return epcf;
}
static char *ngx_epoll_init_conf(ngx_cycle_t *cycle, void *conf)
{
ngx_epoll_conf_t *epcf = conf;
ngx_conf_init_unsigned_value(epcf->events, 512);
return NGX_CONF_OK;
}
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