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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 18:24:20 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 18:24:20 +0000 |
commit | 483eb2f56657e8e7f419ab1a4fab8dce9ade8609 (patch) | |
tree | e5d88d25d870d5dedacb6bbdbe2a966086a0a5cf /src/spdk/lib/vhost/rte_vhost/fd_man.c | |
parent | Initial commit. (diff) | |
download | ceph-upstream.tar.xz ceph-upstream.zip |
Adding upstream version 14.2.21.upstream/14.2.21upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/spdk/lib/vhost/rte_vhost/fd_man.c')
-rw-r--r-- | src/spdk/lib/vhost/rte_vhost/fd_man.c | 300 |
1 files changed, 300 insertions, 0 deletions
diff --git a/src/spdk/lib/vhost/rte_vhost/fd_man.c b/src/spdk/lib/vhost/rte_vhost/fd_man.c new file mode 100644 index 00000000..2ceacc9a --- /dev/null +++ b/src/spdk/lib/vhost/rte_vhost/fd_man.c @@ -0,0 +1,300 @@ +/*- + * 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 <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/socket.h> +#include <sys/time.h> +#include <sys/types.h> +#include <unistd.h> +#include <string.h> + +#include <rte_common.h> +#include <rte_log.h> + +#include "fd_man.h" + +#define FDPOLLERR (POLLERR | POLLHUP | POLLNVAL) + +static int +get_last_valid_idx(struct fdset *pfdset, int last_valid_idx) +{ + int i; + + for (i = last_valid_idx; i >= 0 && pfdset->fd[i].fd == -1; i--) + ; + + return i; +} + +static void +fdset_move(struct fdset *pfdset, int dst, int src) +{ + pfdset->fd[dst] = pfdset->fd[src]; + pfdset->rwfds[dst] = pfdset->rwfds[src]; +} + +static void +fdset_shrink_nolock(struct fdset *pfdset) +{ + int i; + int last_valid_idx = get_last_valid_idx(pfdset, pfdset->num - 1); + + for (i = 0; i < last_valid_idx; i++) { + if (pfdset->fd[i].fd != -1) + continue; + + fdset_move(pfdset, i, last_valid_idx); + last_valid_idx = get_last_valid_idx(pfdset, last_valid_idx - 1); + } + pfdset->num = last_valid_idx + 1; +} + +/* + * Find deleted fd entries and remove them + */ +static void +fdset_shrink(struct fdset *pfdset) +{ + pthread_mutex_lock(&pfdset->fd_mutex); + fdset_shrink_nolock(pfdset); + pthread_mutex_unlock(&pfdset->fd_mutex); +} + +/** + * Returns the index in the fdset for a given fd. + * @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; + + for (i = 0; i < pfdset->num && pfdset->fd[i].fd != fd; i++) + ; + + return i == pfdset->num ? -1 : i; +} + +static void +fdset_add_fd(struct fdset *pfdset, int idx, int fd, + fd_cb rcb, fd_cb wcb, void *dat) +{ + struct fdentry *pfdentry = &pfdset->fd[idx]; + struct pollfd *pfd = &pfdset->rwfds[idx]; + + pfdentry->fd = fd; + pfdentry->rcb = rcb; + pfdentry->wcb = wcb; + pfdentry->dat = dat; + + pfd->fd = fd; + pfd->events = rcb ? POLLIN : 0; + pfd->events |= wcb ? POLLOUT : 0; + pfd->revents = 0; +} + +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->fd[i].dat = NULL; + } + 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; + + pthread_mutex_lock(&pfdset->fd_mutex); + i = pfdset->num < MAX_FDS ? pfdset->num++ : -1; + if (i == -1) { + fdset_shrink_nolock(pfdset); + i = pfdset->num < MAX_FDS ? pfdset->num++ : -1; + if (i == -1) { + pthread_mutex_unlock(&pfdset->fd_mutex); + return -2; + } + } + + fdset_add_fd(pfdset, i, fd, rcb, wcb, dat); + pthread_mutex_unlock(&pfdset->fd_mutex); + + return 0; +} + +/** + * Unregister the fd from the fdset. + * Returns context of a given fd or NULL. + */ +void * +fdset_del(struct fdset *pfdset, int fd) +{ + int i; + void *dat = NULL; + + if (pfdset == NULL || fd == -1) + return NULL; + + do { + pthread_mutex_lock(&pfdset->fd_mutex); + + i = fdset_find_fd(pfdset, fd); + if (i != -1 && pfdset->fd[i].busy == 0) { + /* busy indicates r/wcb is executing! */ + dat = pfdset->fd[i].dat; + pfdset->fd[i].fd = -1; + pfdset->fd[i].rcb = pfdset->fd[i].wcb = NULL; + pfdset->fd[i].dat = NULL; + i = -1; + } + pthread_mutex_unlock(&pfdset->fd_mutex); + } while (i != -1); + + return dat; +} + + +/** + * 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. + * + * Before the callback is called, we set the flag to busy status; If other + * thread(now rte_vhost_driver_unregister) calls fdset_del concurrently, it + * will wait until the flag is reset to zero(which indicates the callback is + * finished), then it could free the context after fdset_del. + */ +void * +fdset_event_dispatch(void *arg) +{ + int i; + struct pollfd *pfd; + struct fdentry *pfdentry; + fd_cb rcb, wcb; + void *dat; + int fd, numfds; + int remove1, remove2; + int need_shrink; + struct fdset *pfdset = arg; + + if (pfdset == NULL) + return NULL; + + while (1) { + + /* + * When poll is blocked, other threads might unregister + * listenfds from and register new listenfds into fdset. + * When poll returns, the entries for listenfds in the fdset + * might have been updated. It is ok if there is unwanted call + * for new listenfds. + */ + pthread_mutex_lock(&pfdset->fd_mutex); + numfds = pfdset->num; + pthread_mutex_unlock(&pfdset->fd_mutex); + + poll(pfdset->rwfds, numfds, 1000 /* millisecs */); + + need_shrink = 0; + for (i = 0; i < numfds; i++) { + pthread_mutex_lock(&pfdset->fd_mutex); + + pfdentry = &pfdset->fd[i]; + fd = pfdentry->fd; + pfd = &pfdset->rwfds[i]; + + if (fd < 0) { + need_shrink = 1; + pthread_mutex_unlock(&pfdset->fd_mutex); + continue; + } + + if (!pfd->revents) { + pthread_mutex_unlock(&pfdset->fd_mutex); + continue; + } + + remove1 = remove2 = 0; + + rcb = pfdentry->rcb; + wcb = pfdentry->wcb; + dat = pfdentry->dat; + pfdentry->busy = 1; + + pthread_mutex_unlock(&pfdset->fd_mutex); + + if (rcb && pfd->revents & (POLLIN | FDPOLLERR)) + rcb(fd, dat, &remove1); + if (wcb && pfd->revents & (POLLOUT | FDPOLLERR)) + wcb(fd, dat, &remove2); + pfdentry->busy = 0; + /* + * fdset_del needs to check busy flag. + * We don't allow fdset_del to be called in callback + * directly. + */ + /* + * When we are to clean up the fd from fdset, + * because the fd is closed in the cb, + * the old fd val could be reused by when creates new + * listen fd in another thread, we couldn't call + * fd_set_del. + */ + if (remove1 || remove2) { + pfdentry->fd = -1; + need_shrink = 1; + } + } + + if (need_shrink) + fdset_shrink(pfdset); + } + + return NULL; +} |