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author | Jelmer Vernooij <jelmer@samba.org> | 2008-12-18 14:54:57 +0000 |
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committer | Jelmer Vernooij <jelmer@samba.org> | 2008-12-18 14:54:57 +0000 |
commit | d14c8604653d39dd25736279d34930ee7a3ae103 (patch) | |
tree | 626f700b9b42b798ed7459a5cba5cd27aca9753e /source4/lib/events/events_aio.c | |
parent | 0c0b9c738f0fc1bf8aa64533a5e4e0635b84f58f (diff) | |
parent | fc31f2c5269fd405be96b9a036baf35a60141ccf (diff) | |
download | samba-d14c8604653d39dd25736279d34930ee7a3ae103.tar.gz samba-d14c8604653d39dd25736279d34930ee7a3ae103.tar.bz2 samba-d14c8604653d39dd25736279d34930ee7a3ae103.zip |
Merge branch 'master' of ssh://git.samba.org/data/git/samba into pyregistry
Diffstat (limited to 'source4/lib/events/events_aio.c')
-rw-r--r-- | source4/lib/events/events_aio.c | 567 |
1 files changed, 0 insertions, 567 deletions
diff --git a/source4/lib/events/events_aio.c b/source4/lib/events/events_aio.c deleted file mode 100644 index e30213acbc..0000000000 --- a/source4/lib/events/events_aio.c +++ /dev/null @@ -1,567 +0,0 @@ -/* - Unix SMB/CIFS implementation. - - main select loop and event handling - aio/epoll hybrid implementation - - Copyright (C) Andrew Tridgell 2006 - - based on events_standard.c - - 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 3 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, see <http://www.gnu.org/licenses/>. -*/ -/* - this is a very strange beast. The Linux AIO implementation doesn't - yet integrate properly with epoll, but there is a kernel patch that - allows the aio wait primitives to be used to wait for epoll events, - and this can be used to give us a unified event system incorporating - both aio events and epoll events - - this is _very_ experimental code -*/ - -#include "system/filesys.h" -#include "replace.h" -#include "events.h" -#include "events_internal.h" -#include "events_util.h" -#include <sys/epoll.h> -#include <libaio.h> - -#define MAX_AIO_QUEUE_DEPTH 100 -#ifndef IOCB_CMD_EPOLL_WAIT -#define IOCB_CMD_EPOLL_WAIT 9 -#endif - -struct aio_event_context { - /* a pointer back to the generic event_context */ - struct event_context *ev; - - /* list of filedescriptor events */ - struct fd_event *fd_events; - - /* number of registered fd event handlers */ - int num_fd_events; - - uint32_t destruction_count; - - io_context_t ioctx; - - struct epoll_event epevent[MAX_AIO_QUEUE_DEPTH]; - - struct iocb *epoll_iocb; - - int epoll_fd; - int is_epoll_set; - pid_t pid; -}; - -struct aio_event { - struct event_context *event_ctx; - struct iocb iocb; - void *private_data; - event_aio_handler_t handler; -}; - -/* - map from EVENT_FD_* to EPOLLIN/EPOLLOUT -*/ -static uint32_t epoll_map_flags(uint16_t flags) -{ - uint32_t ret = 0; - if (flags & EVENT_FD_READ) ret |= (EPOLLIN | EPOLLERR | EPOLLHUP); - if (flags & EVENT_FD_WRITE) ret |= (EPOLLOUT | EPOLLERR | EPOLLHUP); - return ret; -} - -/* - free the epoll fd -*/ -static int aio_ctx_destructor(struct aio_event_context *aio_ev) -{ - io_queue_release(aio_ev->ioctx); - close(aio_ev->epoll_fd); - aio_ev->epoll_fd = -1; - return 0; -} - -static void epoll_add_event(struct aio_event_context *aio_ev, struct fd_event *fde); - -/* - reopen the epoll handle when our pid changes - see http://junkcode.samba.org/ftp/unpacked/junkcode/epoll_fork.c for an - demonstration of why this is needed - */ -static void epoll_check_reopen(struct aio_event_context *aio_ev) -{ - struct fd_event *fde; - - if (aio_ev->pid == getpid()) { - return; - } - - close(aio_ev->epoll_fd); - aio_ev->epoll_fd = epoll_create(MAX_AIO_QUEUE_DEPTH); - if (aio_ev->epoll_fd == -1) { - ev_debug(aio_ev->ev, EV_DEBUG_FATAL, "Failed to recreate epoll handle after fork\n"); - return; - } - aio_ev->pid = getpid(); - for (fde=aio_ev->fd_events;fde;fde=fde->next) { - epoll_add_event(aio_ev, fde); - } -} - -#define EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT (1<<0) -#define EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR (1<<1) -#define EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR (1<<2) - -/* - add the epoll event to the given fd_event -*/ -static void epoll_add_event(struct aio_event_context *aio_ev, struct fd_event *fde) -{ - struct epoll_event event; - if (aio_ev->epoll_fd == -1) return; - - fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR; - - /* if we don't want events yet, don't add an aio_event */ - if (fde->flags == 0) return; - - memset(&event, 0, sizeof(event)); - event.events = epoll_map_flags(fde->flags); - event.data.ptr = fde; - epoll_ctl(aio_ev->epoll_fd, EPOLL_CTL_ADD, fde->fd, &event); - fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT; - - /* only if we want to read we want to tell the event handler about errors */ - if (fde->flags & EVENT_FD_READ) { - fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR; - } -} - -/* - delete the epoll event for given fd_event -*/ -static void epoll_del_event(struct aio_event_context *aio_ev, struct fd_event *fde) -{ - struct epoll_event event; - - DLIST_REMOVE(aio_ev->fd_events, fde); - - if (aio_ev->epoll_fd == -1) return; - - fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR; - - /* if there's no aio_event, we don't need to delete it */ - if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT)) return; - - ZERO_STRUCT(event); - event.events = epoll_map_flags(fde->flags); - event.data.ptr = fde; - epoll_ctl(aio_ev->epoll_fd, EPOLL_CTL_DEL, fde->fd, &event); - - fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT; -} - -/* - change the epoll event to the given fd_event -*/ -static void epoll_mod_event(struct aio_event_context *aio_ev, struct fd_event *fde) -{ - struct epoll_event event; - if (aio_ev->epoll_fd == -1) return; - - fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR; - - ZERO_STRUCT(event); - event.events = epoll_map_flags(fde->flags); - event.data.ptr = fde; - epoll_ctl(aio_ev->epoll_fd, EPOLL_CTL_MOD, fde->fd, &event); - - /* only if we want to read we want to tell the event handler about errors */ - if (fde->flags & EVENT_FD_READ) { - fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR; - } -} - -static void epoll_change_event(struct aio_event_context *aio_ev, struct fd_event *fde) -{ - bool got_error = (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR); - bool want_read = (fde->flags & EVENT_FD_READ); - bool want_write= (fde->flags & EVENT_FD_WRITE); - - if (aio_ev->epoll_fd == -1) return; - - fde->additional_flags &= ~EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR; - - /* there's already an event */ - if (fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_HAS_EVENT) { - if (want_read || (want_write && !got_error)) { - epoll_mod_event(aio_ev, fde); - return; - } - epoll_del_event(aio_ev, fde); - return; - } - - /* there's no aio_event attached to the fde */ - if (want_read || (want_write && !got_error)) { - DLIST_ADD(aio_ev->fd_events, fde); - epoll_add_event(aio_ev, fde); - return; - } -} - -static int setup_epoll_wait(struct aio_event_context *aio_ev) -{ - if (aio_ev->is_epoll_set) { - return 0; - } - memset(aio_ev->epoll_iocb, 0, sizeof(*aio_ev->epoll_iocb)); - aio_ev->epoll_iocb->aio_fildes = aio_ev->epoll_fd; - aio_ev->epoll_iocb->aio_lio_opcode = IOCB_CMD_EPOLL_WAIT; - aio_ev->epoll_iocb->aio_reqprio = 0; - - aio_ev->epoll_iocb->u.c.nbytes = MAX_AIO_QUEUE_DEPTH; - aio_ev->epoll_iocb->u.c.offset = -1; - aio_ev->epoll_iocb->u.c.buf = aio_ev->epevent; - - if (io_submit(aio_ev->ioctx, 1, &aio_ev->epoll_iocb) != 1) { - return -1; - } - aio_ev->is_epoll_set = 1; - - return 0; -} - - -/* - event loop handling using aio/epoll hybrid -*/ -static int aio_event_loop(struct aio_event_context *aio_ev, struct timeval *tvalp) -{ - int ret, i; - uint32_t destruction_count = ++aio_ev->destruction_count; - struct timespec timeout; - struct io_event events[8]; - - if (aio_ev->epoll_fd == -1) return -1; - - if (aio_ev->ev->num_signal_handlers && - common_event_check_signal(aio_ev->ev)) { - return 0; - } - - if (tvalp) { - timeout.tv_sec = tvalp->tv_sec; - timeout.tv_nsec = tvalp->tv_usec; - timeout.tv_nsec *= 1000; - } - - if (setup_epoll_wait(aio_ev) < 0) - return -1; - - ret = io_getevents(aio_ev->ioctx, 1, 8, - events, tvalp?&timeout:NULL); - - if (ret == -EINTR) { - if (aio_ev->ev->num_signal_handlers) { - common_event_check_signal(aio_ev->ev); - } - return 0; - } - - if (ret == 0 && tvalp) { - /* we don't care about a possible delay here */ - common_event_loop_timer_delay(aio_ev->ev); - return 0; - } - - for (i=0;i<ret;i++) { - struct io_event *event = &events[i]; - struct iocb *finished = event->obj; - - switch (finished->aio_lio_opcode) { - case IO_CMD_PWRITE: - case IO_CMD_PREAD: { - struct aio_event *ae = talloc_get_type(finished->data, - struct aio_event); - if (ae) { - talloc_set_destructor(ae, NULL); - ae->handler(ae->event_ctx, ae, - event->res, ae->private_data); - talloc_free(ae); - } - break; - } - case IOCB_CMD_EPOLL_WAIT: { - struct epoll_event *ep = (struct epoll_event *)finished->u.c.buf; - struct fd_event *fde; - uint16_t flags = 0; - int j; - - aio_ev->is_epoll_set = 0; - - for (j=0; j<event->res; j++, ep++) { - fde = talloc_get_type(ep->data.ptr, - struct fd_event); - if (fde == NULL) { - return -1; - } - if (ep->events & (EPOLLHUP|EPOLLERR)) { - fde->additional_flags |= EPOLL_ADDITIONAL_FD_FLAG_GOT_ERROR; - if (!(fde->additional_flags & EPOLL_ADDITIONAL_FD_FLAG_REPORT_ERROR)) { - epoll_del_event(aio_ev, fde); - continue; - } - flags |= EVENT_FD_READ; - } - if (ep->events & EPOLLIN) flags |= EVENT_FD_READ; - if (ep->events & EPOLLOUT) flags |= EVENT_FD_WRITE; - if (flags) { - fde->handler(aio_ev->ev, fde, flags, fde->private_data); - } - } - break; - } - } - if (destruction_count != aio_ev->destruction_count) { - return 0; - } - } - - return 0; -} - -/* - create a aio_event_context structure. -*/ -static int aio_event_context_init(struct event_context *ev) -{ - struct aio_event_context *aio_ev; - - aio_ev = talloc_zero(ev, struct aio_event_context); - if (!aio_ev) return -1; - - aio_ev->ev = ev; - aio_ev->epoll_iocb = talloc(aio_ev, struct iocb); - - if (io_queue_init(MAX_AIO_QUEUE_DEPTH, &aio_ev->ioctx) != 0) { - talloc_free(aio_ev); - return -1; - } - - aio_ev->epoll_fd = epoll_create(MAX_AIO_QUEUE_DEPTH); - if (aio_ev->epoll_fd == -1) { - talloc_free(aio_ev); - return -1; - } - aio_ev->pid = getpid(); - - talloc_set_destructor(aio_ev, aio_ctx_destructor); - - ev->additional_data = aio_ev; - - if (setup_epoll_wait(aio_ev) < 0) { - talloc_free(aio_ev); - return -1; - } - - return 0; -} - -/* - destroy an fd_event -*/ -static int aio_event_fd_destructor(struct fd_event *fde) -{ - struct event_context *ev = fde->event_ctx; - struct aio_event_context *aio_ev = talloc_get_type(ev->additional_data, - struct aio_event_context); - - epoll_check_reopen(aio_ev); - - aio_ev->num_fd_events--; - aio_ev->destruction_count++; - - epoll_del_event(aio_ev, fde); - - if (fde->flags & EVENT_FD_AUTOCLOSE) { - close(fde->fd); - fde->fd = -1; - } - - return 0; -} - -/* - add a fd based event - return NULL on failure (memory allocation error) -*/ -static struct fd_event *aio_event_add_fd(struct event_context *ev, TALLOC_CTX *mem_ctx, - int fd, uint16_t flags, - event_fd_handler_t handler, - void *private_data) -{ - struct aio_event_context *aio_ev = talloc_get_type(ev->additional_data, - struct aio_event_context); - struct fd_event *fde; - - epoll_check_reopen(aio_ev); - - fde = talloc(mem_ctx?mem_ctx:ev, struct fd_event); - if (!fde) return NULL; - - fde->event_ctx = ev; - fde->fd = fd; - fde->flags = flags; - fde->handler = handler; - fde->private_data = private_data; - fde->additional_flags = 0; - fde->additional_data = NULL; - - aio_ev->num_fd_events++; - talloc_set_destructor(fde, aio_event_fd_destructor); - - DLIST_ADD(aio_ev->fd_events, fde); - epoll_add_event(aio_ev, fde); - - return fde; -} - - -/* - return the fd event flags -*/ -static uint16_t aio_event_get_fd_flags(struct fd_event *fde) -{ - return fde->flags; -} - -/* - set the fd event flags -*/ -static void aio_event_set_fd_flags(struct fd_event *fde, uint16_t flags) -{ - struct event_context *ev; - struct aio_event_context *aio_ev; - - if (fde->flags == flags) return; - - ev = fde->event_ctx; - aio_ev = talloc_get_type(ev->additional_data, struct aio_event_context); - - fde->flags = flags; - - epoll_check_reopen(aio_ev); - - epoll_change_event(aio_ev, fde); -} - -/* - do a single event loop using the events defined in ev -*/ -static int aio_event_loop_once(struct event_context *ev) -{ - struct aio_event_context *aio_ev = talloc_get_type(ev->additional_data, - struct aio_event_context); - struct timeval tval; - - tval = common_event_loop_timer_delay(ev); - if (ev_timeval_is_zero(&tval)) { - return 0; - } - - epoll_check_reopen(aio_ev); - - return aio_event_loop(aio_ev, &tval); -} - -/* - return on failure or (with 0) if all fd events are removed -*/ -static int aio_event_loop_wait(struct event_context *ev) -{ - struct aio_event_context *aio_ev = talloc_get_type(ev->additional_data, - struct aio_event_context); - while (aio_ev->num_fd_events) { - if (aio_event_loop_once(ev) != 0) { - break; - } - } - - return 0; -} - -/* - called when a disk IO event needs to be cancelled -*/ -static int aio_destructor(struct aio_event *ae) -{ - struct event_context *ev = ae->event_ctx; - struct aio_event_context *aio_ev = talloc_get_type(ev->additional_data, - struct aio_event_context); - struct io_event result; - io_cancel(aio_ev->ioctx, &ae->iocb, &result); - /* TODO: handle errors from io_cancel()! */ - return 0; -} - -/* submit an aio disk IO event */ -static struct aio_event *aio_event_add_aio(struct event_context *ev, - TALLOC_CTX *mem_ctx, - struct iocb *iocb, - event_aio_handler_t handler, - void *private_data) -{ - struct aio_event_context *aio_ev = talloc_get_type(ev->additional_data, - struct aio_event_context); - struct iocb *iocbp; - struct aio_event *ae = talloc(mem_ctx?mem_ctx:ev, struct aio_event); - if (ae == NULL) return NULL; - - ae->event_ctx = ev; - ae->iocb = *iocb; - ae->handler = handler; - ae->private_data = private_data; - iocbp = &ae->iocb; - - if (io_submit(aio_ev->ioctx, 1, &iocbp) != 1) { - talloc_free(ae); - return NULL; - } - ae->iocb.data = ae; - talloc_set_destructor(ae, aio_destructor); - - return ae; -} - -static const struct event_ops aio_event_ops = { - .context_init = aio_event_context_init, - .add_fd = aio_event_add_fd, - .add_aio = aio_event_add_aio, - .get_fd_flags = aio_event_get_fd_flags, - .set_fd_flags = aio_event_set_fd_flags, - .add_timed = common_event_add_timed, - .add_signal = common_event_add_signal, - .loop_once = aio_event_loop_once, - .loop_wait = aio_event_loop_wait, -}; - -bool events_aio_init(void) -{ - return event_register_backend("aio", &aio_event_ops); -} - |