From: Huawei Xie Date: Mon, 23 Feb 2015 17:36:30 +0000 (+0000) Subject: vhost: add select based event driven processing X-Git-Tag: spdx-start~9607 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=fbf7e07ca1423f7cbf96063a7e522a07b6c43fc9;p=dpdk.git vhost: add select based event driven processing for more generic event driven processing, refer to: http://libevent.org/ Signed-off-by: Huawei Xie Acked-by: Konstantin Ananyev Acked-by: Tetsuya Mukawa --- diff --git a/lib/librte_vhost/vhost_user/fd_man.c b/lib/librte_vhost/vhost_user/fd_man.c new file mode 100644 index 0000000000..929fbc3674 --- /dev/null +++ b/lib/librte_vhost/vhost_user/fd_man.c @@ -0,0 +1,207 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2010-2014 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#include "fd_man.h" + +/** + * Returns the index in the fdset for a given fd. + * If fd is -1, it means to search for a free entry. + * @return + * index for the fd, or -1 if fd isn't in the fdset. + */ +static int +fdset_find_fd(struct fdset *pfdset, int fd) +{ + int i; + + if (pfdset == NULL) + return -1; + + for (i = 0; i < MAX_FDS && pfdset->fd[i].fd != fd; i++) + ; + + return i == MAX_FDS ? -1 : i; +} + +static int +fdset_find_free_slot(struct fdset *pfdset) +{ + return fdset_find_fd(pfdset, -1); +} + +static void +fdset_add_fd(struct fdset *pfdset, int idx, int fd, + fd_cb rcb, fd_cb wcb, void *dat) +{ + struct fdentry *pfdentry; + + if (pfdset == NULL || idx >= MAX_FDS) + return; + + pfdentry = &pfdset->fd[idx]; + pfdentry->fd = fd; + pfdentry->rcb = rcb; + pfdentry->wcb = wcb; + pfdentry->dat = dat; +} + +/** + * Fill the read/write fd_set with the fds in the fdset. + * @return + * the maximum fds filled in the read/write fd_set. + */ +static int +fdset_fill(fd_set *rfset, fd_set *wfset, struct fdset *pfdset) +{ + struct fdentry *pfdentry; + int i, maxfds = -1; + int num = MAX_FDS; + + if (pfdset == NULL) + return -1; + + for (i = 0; i < num; i++) { + pfdentry = &pfdset->fd[i]; + if (pfdentry->fd != -1) { + int added = 0; + if (pfdentry->rcb && rfset) { + FD_SET(pfdentry->fd, rfset); + added = 1; + } + if (pfdentry->wcb && wfset) { + FD_SET(pfdentry->fd, wfset); + added = 1; + } + if (added) + maxfds = pfdentry->fd < maxfds ? + maxfds : pfdentry->fd; + } + } + return maxfds; +} + +void +fdset_init(struct fdset *pfdset) +{ + int i; + + if (pfdset == NULL) + return; + + for (i = 0; i < MAX_FDS; i++) + pfdset->fd[i].fd = -1; + pfdset->num = 0; +} + +/** + * Register the fd in the fdset with read/write handler and context. + */ +int +fdset_add(struct fdset *pfdset, int fd, fd_cb rcb, fd_cb wcb, void *dat) +{ + int i; + + if (pfdset == NULL || fd == -1) + return -1; + + /* Find a free slot in the list. */ + i = fdset_find_free_slot(pfdset); + if (i == -1) + return -2; + + fdset_add_fd(pfdset, i, fd, rcb, wcb, dat); + pfdset->num++; + + return 0; +} + +/** + * Unregister the fd from the fdset. + */ +void +fdset_del(struct fdset *pfdset, int fd) +{ + int i; + + i = fdset_find_fd(pfdset, fd); + if (i != -1 && fd != -1) { + pfdset->fd[i].fd = -1; + pfdset->fd[i].rcb = pfdset->fd[i].wcb = NULL; + pfdset->num--; + } +} + +/** + * This functions runs in infinite blocking loop until there is no fd in + * pfdset. It calls corresponding r/w handler if there is event on the fd. + */ +void +fdset_event_dispatch(struct fdset *pfdset) +{ + fd_set rfds, wfds; + int i, maxfds; + struct fdentry *pfdentry; + int num = MAX_FDS; + + if (pfdset == NULL) + return; + + while (1) { + FD_ZERO(&rfds); + FD_ZERO(&wfds); + maxfds = fdset_fill(&rfds, &wfds, pfdset); + if (maxfds == -1) + return; + + select(maxfds + 1, &rfds, &wfds, NULL, NULL); + + for (i = 0; i < num; i++) { + pfdentry = &pfdset->fd[i]; + if (pfdentry->fd >= 0 && FD_ISSET(pfdentry->fd, &rfds) && pfdentry->rcb) + pfdentry->rcb(pfdentry->fd, pfdentry->dat); + if (pfdentry->fd >= 0 && FD_ISSET(pfdentry->fd, &wfds) && pfdentry->wcb) + pfdentry->wcb(pfdentry->fd, pfdentry->dat); + } + } +} diff --git a/lib/librte_vhost/vhost_user/fd_man.h b/lib/librte_vhost/vhost_user/fd_man.h new file mode 100644 index 0000000000..26b4619599 --- /dev/null +++ b/lib/librte_vhost/vhost_user/fd_man.h @@ -0,0 +1,64 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2010-2014 Intel Corporation. All rights reserved. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * * Neither the name of Intel Corporation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef _FD_MAN_H_ +#define _FD_MAN_H_ +#include + +#define MAX_FDS 1024 + +typedef void (*fd_cb)(int fd, void *dat); + +struct fdentry { + int fd; /* -1 indicates this entry is empty */ + fd_cb rcb; /* callback when this fd is readable. */ + fd_cb wcb; /* callback when this fd is writeable.*/ + void *dat; /* fd context */ +}; + +struct fdset { + struct fdentry fd[MAX_FDS]; + int num; /* current fd number of this fdset */ +}; + + +void fdset_init(struct fdset *pfdset); + +int fdset_add(struct fdset *pfdset, int fd, + fd_cb rcb, fd_cb wcb, void *dat); + +void fdset_del(struct fdset *pfdset, int fd); + +void fdset_event_dispatch(struct fdset *pfdset); + +#endif