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compress read and write events for the same file descriptor into on poll

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descriptor; from Nick Mathewson plus bug fixes from me.


svn:r151
This commit is contained in:
Niels Provos 2005-04-23 02:40:26 +00:00
parent bca504e41c
commit 2fa38549d7
1 changed files with 70 additions and 25 deletions
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95
poll.c
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@ -55,8 +55,13 @@ extern volatile sig_atomic_t evsignal_caught;
struct pollop {
int event_count; /* Highest number alloc */
int fd_count; /* Size of idxplus1_by_fd */
struct pollfd *event_set;
struct event **event_back;
struct event **event_r_back;
struct event **event_w_back;
int *idxplus1_by_fd; /* Index into event_set by fd; we add 1 so
* that 0 (which is easy to memset) can mean
* "no entry." */
sigset_t evsigmask;
};
@ -108,13 +113,19 @@ poll_recalc(struct event_base *base, void *arg, int max)
int
poll_dispatch(struct event_base *base, void *arg, struct timeval *tv)
{
int res, i, count, sec, nfds;
int res, i, count, fd_count, sec, nfds;
struct event *ev;
struct pollop *pop = arg;
int *idxplus1_by_fd;
count = pop->event_count;
fd_count = pop->fd_count;
idxplus1_by_fd = pop->idxplus1_by_fd;
memset(idxplus1_by_fd, 0, sizeof(int)*fd_count);
nfds = 0;
TAILQ_FOREACH(ev, &base->eventqueue, ev_next) {
struct pollfd *pfd = NULL;
if (nfds + 1 >= count) {
if (count < 32)
count = 32;
@ -128,34 +139,61 @@ poll_dispatch(struct event_base *base, void *arg, struct timeval *tv)
event_warn("realloc");
return (-1);
}
pop->event_back = realloc(pop->event_back,
pop->event_r_back = realloc(pop->event_r_back,
count * sizeof(struct event *));
if (pop->event_back == NULL) {
pop->event_w_back = realloc(pop->event_w_back,
count * sizeof(struct event *));
if (pop->event_r_back == NULL ||
pop->event_w_back == NULL) {
event_warn("realloc");
return (-1);
}
pop->event_count = count;
}
if (!(ev->ev_events & (EV_READ|EV_WRITE)))
continue;
if (ev->ev_fd >= fd_count) {
int new_count;
if (fd_count < 32)
new_count = 32;
else
new_count = fd_count * 2;
while (new_count <= ev->ev_fd)
new_count *= 2;
idxplus1_by_fd = pop->idxplus1_by_fd =
realloc(pop->idxplus1_by_fd, new_count*sizeof(int));
if (idxplus1_by_fd == NULL) {
event_warn("realloc");
return (-1);
}
memset(pop->idxplus1_by_fd+sizeof(int)*fd_count,
0, sizeof(int)*(new_count-fd_count));
fd_count = pop->fd_count = new_count;
}
i = idxplus1_by_fd[ev->ev_fd] - 1;
if (i >= 0) {
pfd = &pop->event_set[i];
} else {
i = nfds++;
pfd = &pop->event_set[i];
pop->event_w_back[i] = pop->event_r_back[i] = NULL;
pfd->events = 0;
idxplus1_by_fd[ev->ev_fd] = i + 1;
}
if (ev->ev_events & EV_WRITE) {
struct pollfd *pfd = &pop->event_set[nfds];
pfd->fd = ev->ev_fd;
pfd->events = POLLOUT;
pfd->events |= POLLOUT;
pfd->revents = 0;
pop->event_back[nfds] = ev;
nfds++;
pop->event_w_back[i] = ev;
}
if (ev->ev_events & EV_READ) {
struct pollfd *pfd = &pop->event_set[nfds];
pfd->fd = ev->ev_fd;
pfd->events = POLLIN;
pfd->events |= POLLIN;
pfd->revents = 0;
pop->event_back[nfds] = ev;
nfds++;
pop->event_r_back[i] = ev;
}
}
@ -186,6 +224,7 @@ poll_dispatch(struct event_base *base, void *arg, struct timeval *tv)
for (i = 0; i < nfds; i++) {
int what = pop->event_set[i].revents;
struct event *r_ev = NULL, *w_ev = NULL;
res = 0;
@ -194,21 +233,27 @@ poll_dispatch(struct event_base *base, void *arg, struct timeval *tv)
what |= POLLIN|POLLOUT;
if (what & POLLERR)
what |= POLLIN|POLLOUT;
if (what & POLLIN)
if (what & POLLIN) {
res |= EV_READ;
if (what & POLLOUT)
r_ev = pop->event_r_back[i];
}
if (what & POLLOUT) {
res |= EV_WRITE;
w_ev = pop->event_w_back[i];
}
if (res == 0)
continue;
ev = pop->event_back[i];
res &= ev->ev_events;
if (res) {
if (!(ev->ev_events & EV_PERSIST))
event_del(ev);
event_active(ev, res, 1);
}
if (r_ev && (res & r_ev->ev_events)) {
if (!(r_ev->ev_events & EV_PERSIST))
event_del(r_ev);
event_active(r_ev, res & r_ev->ev_events, 1);
}
if (w_ev && w_ev != r_ev && (res & w_ev->ev_events)) {
if (!(w_ev->ev_events & EV_PERSIST))
event_del(w_ev);
event_active(w_ev, res & w_ev->ev_events, 1);
}
}
return (0);