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37 #include <sys/socket.h>
38 #include <sys/select.h>
40 #include <sys/types.h>
43 #include <rte_common.h>
49 * Returns the index in the fdset for a given fd.
50 * If fd is -1, it means to search for a free entry.
52 * index for the fd, or -1 if fd isn't in the fdset.
55 fdset_find_fd(struct fdset *pfdset, int fd)
62 for (i = 0; i < MAX_FDS && pfdset->fd[i].fd != fd; i++)
65 return i == MAX_FDS ? -1 : i;
69 fdset_find_free_slot(struct fdset *pfdset)
71 return fdset_find_fd(pfdset, -1);
75 fdset_add_fd(struct fdset *pfdset, int idx, int fd,
76 fd_cb rcb, fd_cb wcb, void *dat)
78 struct fdentry *pfdentry;
80 if (pfdset == NULL || idx >= MAX_FDS)
83 pfdentry = &pfdset->fd[idx];
91 * Fill the read/write fd_set with the fds in the fdset.
93 * the maximum fds filled in the read/write fd_set.
96 fdset_fill(fd_set *rfset, fd_set *wfset, struct fdset *pfdset)
98 struct fdentry *pfdentry;
105 for (i = 0; i < num; i++) {
106 pfdentry = &pfdset->fd[i];
107 if (pfdentry->fd != -1) {
109 if (pfdentry->rcb && rfset) {
110 FD_SET(pfdentry->fd, rfset);
113 if (pfdentry->wcb && wfset) {
114 FD_SET(pfdentry->fd, wfset);
118 maxfds = pfdentry->fd < maxfds ?
119 maxfds : pfdentry->fd;
126 fdset_init(struct fdset *pfdset)
133 for (i = 0; i < MAX_FDS; i++)
134 pfdset->fd[i].fd = -1;
139 * Register the fd in the fdset with read/write handler and context.
142 fdset_add(struct fdset *pfdset, int fd, fd_cb rcb, fd_cb wcb, void *dat)
146 if (pfdset == NULL || fd == -1)
149 pthread_mutex_lock(&pfdset->fd_mutex);
151 /* Find a free slot in the list. */
152 i = fdset_find_free_slot(pfdset);
156 fdset_add_fd(pfdset, i, fd, rcb, wcb, dat);
159 pthread_mutex_unlock(&pfdset->fd_mutex);
165 * Unregister the fd from the fdset.
168 fdset_del(struct fdset *pfdset, int fd)
172 if (pfdset == NULL || fd == -1)
176 pthread_mutex_lock(&pfdset->fd_mutex);
178 i = fdset_find_fd(pfdset, fd);
179 if (i != -1 && pfdset->fd[i].busy == 0) {
180 /* busy indicates r/wcb is executing! */
181 pfdset->fd[i].fd = -1;
182 pfdset->fd[i].rcb = pfdset->fd[i].wcb = NULL;
186 pthread_mutex_unlock(&pfdset->fd_mutex);
191 * This functions runs in infinite blocking loop until there is no fd in
192 * pfdset. It calls corresponding r/w handler if there is event on the fd.
194 * Before the callback is called, we set the flag to busy status; If other
195 * thread(now rte_vhost_driver_unregister) calls fdset_del concurrently, it
196 * will wait until the flag is reset to zero(which indicates the callback is
197 * finished), then it could free the context after fdset_del.
200 fdset_event_dispatch(struct fdset *pfdset)
204 struct fdentry *pfdentry;
209 int remove1, remove2;
221 pthread_mutex_lock(&pfdset->fd_mutex);
223 maxfds = fdset_fill(&rfds, &wfds, pfdset);
225 pthread_mutex_unlock(&pfdset->fd_mutex);
227 ret = select(maxfds + 1, &rfds, &wfds, NULL, &tv);
231 for (i = 0; i < num; i++) {
232 remove1 = remove2 = 0;
233 pthread_mutex_lock(&pfdset->fd_mutex);
234 pfdentry = &pfdset->fd[i];
240 pthread_mutex_unlock(&pfdset->fd_mutex);
241 if (fd >= 0 && FD_ISSET(fd, &rfds) && rcb)
242 rcb(fd, dat, &remove1);
243 if (fd >= 0 && FD_ISSET(fd, &wfds) && wcb)
244 wcb(fd, dat, &remove2);
247 * fdset_del needs to check busy flag.
248 * We don't allow fdset_del to be called in callback
251 if (remove1 || remove2)
252 fdset_del(pfdset, fd);