diff options
Diffstat (limited to 'libglusterfs/src/event-epoll.c')
| -rw-r--r-- | libglusterfs/src/event-epoll.c | 463 |
1 files changed, 463 insertions, 0 deletions
diff --git a/libglusterfs/src/event-epoll.c b/libglusterfs/src/event-epoll.c new file mode 100644 index 000000000..06b323624 --- /dev/null +++ b/libglusterfs/src/event-epoll.c @@ -0,0 +1,463 @@ +/* + Copyright (c) 2012 Red Hat, Inc. <http://www.redhat.com> + This file is part of GlusterFS. + + This file is licensed to you under your choice of the GNU Lesser + General Public License, version 3 or any later version (LGPLv3 or + later), or the GNU General Public License, version 2 (GPLv2), in all + cases as published by the Free Software Foundation. +*/ + +#include <sys/poll.h> +#include <pthread.h> +#include <unistd.h> +#include <fcntl.h> +#include <stdlib.h> +#include <errno.h> +#include <string.h> + +#include "logging.h" +#include "event.h" +#include "mem-pool.h" +#include "common-utils.h" + +#ifndef _CONFIG_H +#define _CONFIG_H +#include "config.h" +#endif + + +#ifdef HAVE_SYS_EPOLL_H +#include <sys/epoll.h> + + +static int +__event_getindex (struct event_pool *event_pool, int fd, int idx) +{ + int ret = -1; + int i = 0; + + GF_VALIDATE_OR_GOTO ("event", event_pool, out); + + if (idx > -1 && idx < event_pool->used) { + if (event_pool->reg[idx].fd == fd) + ret = idx; + } + + for (i=0; ret == -1 && i<event_pool->used; i++) { + if (event_pool->reg[i].fd == fd) { + ret = i; + break; + } + } + +out: + return ret; +} + + +static struct event_pool * +event_pool_new_epoll (int count) +{ + struct event_pool *event_pool = NULL; + int epfd = -1; + + event_pool = GF_CALLOC (1, sizeof (*event_pool), + gf_common_mt_event_pool); + + if (!event_pool) + goto out; + + event_pool->count = count; + event_pool->reg = GF_CALLOC (event_pool->count, + sizeof (*event_pool->reg), + gf_common_mt_reg); + + if (!event_pool->reg) { + GF_FREE (event_pool); + event_pool = NULL; + goto out; + } + + epfd = epoll_create (count); + + if (epfd == -1) { + gf_log ("epoll", GF_LOG_ERROR, "epoll fd creation failed (%s)", + strerror (errno)); + GF_FREE (event_pool->reg); + GF_FREE (event_pool); + event_pool = NULL; + goto out; + } + + event_pool->fd = epfd; + + event_pool->count = count; + + pthread_mutex_init (&event_pool->mutex, NULL); + pthread_cond_init (&event_pool->cond, NULL); + +out: + return event_pool; +} + + +int +event_register_epoll (struct event_pool *event_pool, int fd, + event_handler_t handler, + void *data, int poll_in, int poll_out) +{ + int idx = -1; + int ret = -1; + struct epoll_event epoll_event = {0, }; + struct event_data *ev_data = (void *)&epoll_event.data; + + + GF_VALIDATE_OR_GOTO ("event", event_pool, out); + + pthread_mutex_lock (&event_pool->mutex); + { + if (event_pool->count == event_pool->used) { + event_pool->count *= 2; + + event_pool->reg = GF_REALLOC (event_pool->reg, + event_pool->count * + sizeof (*event_pool->reg)); + + if (!event_pool->reg) { + gf_log ("epoll", GF_LOG_ERROR, + "event registry re-allocation failed"); + goto unlock; + } + } + + idx = event_pool->used; + event_pool->used++; + + event_pool->reg[idx].fd = fd; + event_pool->reg[idx].events = EPOLLPRI; + event_pool->reg[idx].handler = handler; + event_pool->reg[idx].data = data; + + switch (poll_in) { + case 1: + event_pool->reg[idx].events |= EPOLLIN; + break; + case 0: + event_pool->reg[idx].events &= ~EPOLLIN; + break; + case -1: + /* do nothing */ + break; + default: + gf_log ("epoll", GF_LOG_ERROR, + "invalid poll_in value %d", poll_in); + break; + } + + switch (poll_out) { + case 1: + event_pool->reg[idx].events |= EPOLLOUT; + break; + case 0: + event_pool->reg[idx].events &= ~EPOLLOUT; + break; + case -1: + /* do nothing */ + break; + default: + gf_log ("epoll", GF_LOG_ERROR, + "invalid poll_out value %d", poll_out); + break; + } + + event_pool->changed = 1; + + epoll_event.events = event_pool->reg[idx].events; + ev_data->fd = fd; + ev_data->idx = idx; + + ret = epoll_ctl (event_pool->fd, EPOLL_CTL_ADD, fd, + &epoll_event); + + if (ret == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "failed to add fd(=%d) to epoll fd(=%d) (%s)", + fd, event_pool->fd, strerror (errno)); + goto unlock; + } + + pthread_cond_broadcast (&event_pool->cond); + } +unlock: + pthread_mutex_unlock (&event_pool->mutex); + +out: + return ret; +} + + +static int +event_unregister_epoll (struct event_pool *event_pool, int fd, int idx_hint) +{ + int idx = -1; + int ret = -1; + + struct epoll_event epoll_event = {0, }; + struct event_data *ev_data = (void *)&epoll_event.data; + int lastidx = -1; + + GF_VALIDATE_OR_GOTO ("event", event_pool, out); + + pthread_mutex_lock (&event_pool->mutex); + { + idx = __event_getindex (event_pool, fd, idx_hint); + + if (idx == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "index not found for fd=%d (idx_hint=%d)", + fd, idx_hint); + errno = ENOENT; + goto unlock; + } + + ret = epoll_ctl (event_pool->fd, EPOLL_CTL_DEL, fd, NULL); + + /* if ret is -1, this array member should never be accessed */ + /* if it is 0, the array member might be used by idx_cache + * in which case the member should not be accessed till + * it is reallocated + */ + + event_pool->reg[idx].fd = -1; + + if (ret == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "fail to del fd(=%d) from epoll fd(=%d) (%s)", + fd, event_pool->fd, strerror (errno)); + goto unlock; + } + + lastidx = event_pool->used - 1; + if (lastidx == idx) { + event_pool->used--; + goto unlock; + } + + epoll_event.events = event_pool->reg[lastidx].events; + ev_data->fd = event_pool->reg[lastidx].fd; + ev_data->idx = idx; + + ret = epoll_ctl (event_pool->fd, EPOLL_CTL_MOD, ev_data->fd, + &epoll_event); + if (ret == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "fail to modify fd(=%d) index %d to %d (%s)", + ev_data->fd, event_pool->used, idx, + strerror (errno)); + goto unlock; + } + + /* just replace the unregistered idx by last one */ + event_pool->reg[idx] = event_pool->reg[lastidx]; + event_pool->used--; + } +unlock: + pthread_mutex_unlock (&event_pool->mutex); + +out: + return ret; +} + + +static int +event_select_on_epoll (struct event_pool *event_pool, int fd, int idx_hint, + int poll_in, int poll_out) +{ + int idx = -1; + int ret = -1; + + struct epoll_event epoll_event = {0, }; + struct event_data *ev_data = (void *)&epoll_event.data; + + + GF_VALIDATE_OR_GOTO ("event", event_pool, out); + + pthread_mutex_lock (&event_pool->mutex); + { + idx = __event_getindex (event_pool, fd, idx_hint); + + if (idx == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "index not found for fd=%d (idx_hint=%d)", + fd, idx_hint); + errno = ENOENT; + goto unlock; + } + + switch (poll_in) { + case 1: + event_pool->reg[idx].events |= EPOLLIN; + break; + case 0: + event_pool->reg[idx].events &= ~EPOLLIN; + break; + case -1: + /* do nothing */ + break; + default: + gf_log ("epoll", GF_LOG_ERROR, + "invalid poll_in value %d", poll_in); + break; + } + + switch (poll_out) { + case 1: + event_pool->reg[idx].events |= EPOLLOUT; + break; + case 0: + event_pool->reg[idx].events &= ~EPOLLOUT; + break; + case -1: + /* do nothing */ + break; + default: + gf_log ("epoll", GF_LOG_ERROR, + "invalid poll_out value %d", poll_out); + break; + } + + epoll_event.events = event_pool->reg[idx].events; + ev_data->fd = fd; + ev_data->idx = idx; + + ret = epoll_ctl (event_pool->fd, EPOLL_CTL_MOD, fd, + &epoll_event); + if (ret == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "failed to modify fd(=%d) events to %d", + fd, epoll_event.events); + } + } +unlock: + pthread_mutex_unlock (&event_pool->mutex); + +out: + return ret; +} + + +static int +event_dispatch_epoll_handler (struct event_pool *event_pool, + struct epoll_event *events, int i) +{ + struct event_data *event_data = NULL; + event_handler_t handler = NULL; + void *data = NULL; + int idx = -1; + int ret = -1; + + + event_data = (void *)&events[i].data; + handler = NULL; + data = NULL; + + pthread_mutex_lock (&event_pool->mutex); + { + idx = __event_getindex (event_pool, event_data->fd, + event_data->idx); + + if (idx == -1) { + gf_log ("epoll", GF_LOG_ERROR, + "index not found for fd(=%d) (idx_hint=%d)", + event_data->fd, event_data->idx); + goto unlock; + } + + handler = event_pool->reg[idx].handler; + data = event_pool->reg[idx].data; + } +unlock: + pthread_mutex_unlock (&event_pool->mutex); + + if (handler) + ret = handler (event_data->fd, event_data->idx, data, + (events[i].events & (EPOLLIN|EPOLLPRI)), + (events[i].events & (EPOLLOUT)), + (events[i].events & (EPOLLERR|EPOLLHUP))); + return ret; +} + + +static int +event_dispatch_epoll (struct event_pool *event_pool) +{ + struct epoll_event *events = NULL; + int size = 0; + int i = 0; + int ret = -1; + + GF_VALIDATE_OR_GOTO ("event", event_pool, out); + + while (1) { + pthread_mutex_lock (&event_pool->mutex); + { + while (event_pool->used == 0) + pthread_cond_wait (&event_pool->cond, + &event_pool->mutex); + + if (event_pool->used > event_pool->evcache_size) { + GF_FREE (event_pool->evcache); + + event_pool->evcache = events = NULL; + + event_pool->evcache_size = + event_pool->used + 256; + + events = GF_CALLOC (event_pool->evcache_size, + sizeof (struct epoll_event), + gf_common_mt_epoll_event); + if (!events) + break; + + event_pool->evcache = events; + } + } + pthread_mutex_unlock (&event_pool->mutex); + + ret = epoll_wait (event_pool->fd, event_pool->evcache, + event_pool->evcache_size, -1); + + if (ret == 0) + /* timeout */ + continue; + + if (ret == -1 && errno == EINTR) + /* sys call */ + continue; + + size = ret; + + for (i = 0; i < size; i++) { + if (!events || !events[i].events) + continue; + + ret = event_dispatch_epoll_handler (event_pool, + events, i); + } + } + +out: + return ret; +} + + +struct event_ops event_ops_epoll = { + .new = event_pool_new_epoll, + .event_register = event_register_epoll, + .event_select_on = event_select_on_epoll, + .event_unregister = event_unregister_epoll, + .event_dispatch = event_dispatch_epoll +}; + +#endif |