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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
commit483eb2f56657e8e7f419ab1a4fab8dce9ade8609 (patch)
treee5d88d25d870d5dedacb6bbdbe2a966086a0a5cf /src/spdk/lib/vhost/rte_vhost/fd_man.c
parentInitial commit. (diff)
downloadceph-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.c300
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;
+}