extmod/modselect: Properly track number of poll objects that are fd's.

Signed-off-by: Damien George <damien@micropython.org>
This commit is contained in:
Damien George 2023-08-14 13:45:53 +10:00
parent 24a6e951ec
commit f6af48416d
3 changed files with 49 additions and 16 deletions

View File

@ -88,8 +88,9 @@ typedef struct _poll_set_t {
#if MICROPY_PY_SELECT_POSIX_OPTIMISATIONS
// Array of pollfd entries for objects that have a file descriptor.
unsigned short alloc;
unsigned short len;
unsigned short alloc; // memory allocated for pollfds
unsigned short max_used; // maximum number of used entries in pollfds
unsigned short used; // actual number of used entries in pollfds
struct pollfd *pollfds;
#endif
} poll_set_t;
@ -98,7 +99,8 @@ STATIC void poll_set_init(poll_set_t *poll_set, size_t n) {
mp_map_init(&poll_set->map, n);
#if MICROPY_PY_SELECT_POSIX_OPTIMISATIONS
poll_set->alloc = 0;
poll_set->len = 0;
poll_set->max_used = 0;
poll_set->used = 0;
poll_set->pollfds = NULL;
#endif
}
@ -142,29 +144,34 @@ STATIC void poll_obj_set_revents(poll_obj_t *poll_obj, mp_uint_t revents) {
STATIC struct pollfd *poll_set_add_fd(poll_set_t *poll_set, int fd) {
struct pollfd *free_slot = NULL;
for (unsigned int i = 0; i < poll_set->len; ++i) {
struct pollfd *slot = &poll_set->pollfds[i];
if (slot->fd == -1) {
free_slot = slot;
break;
}
}
if (free_slot == NULL) {
if (poll_set->len >= poll_set->alloc) {
if (poll_set->used == poll_set->max_used) {
// No free slots below max_used, so expand max_used (and possibly allocate).
if (poll_set->max_used >= poll_set->alloc) {
poll_set->pollfds = m_renew(struct pollfd, poll_set->pollfds, poll_set->alloc, poll_set->alloc + 4);
poll_set->alloc += 4;
}
free_slot = &poll_set->pollfds[poll_set->len++];
free_slot = &poll_set->pollfds[poll_set->max_used++];
} else {
// There should be a free slot below max_used.
for (unsigned int i = 0; i < poll_set->max_used; ++i) {
struct pollfd *slot = &poll_set->pollfds[i];
if (slot->fd == -1) {
free_slot = slot;
break;
}
}
assert(free_slot != NULL);
}
free_slot->fd = fd;
++poll_set->used;
return free_slot;
}
static inline bool poll_set_all_are_fds(poll_set_t *poll_set) {
return poll_set->map.used == poll_set->len;
return poll_set->map.used == poll_set->used;
}
#else
@ -323,7 +330,7 @@ STATIC mp_uint_t poll_set_poll_until_ready_or_timeout(poll_set_t *poll_set, size
}
// Call system poll for those objects that have a file descriptor.
int n_ready = poll(poll_set->pollfds, poll_set->len, t);
int n_ready = poll(poll_set->pollfds, poll_set->max_used, t);
MP_THREAD_GIL_ENTER();
@ -462,6 +469,7 @@ STATIC mp_obj_t poll_unregister(mp_obj_t self_in, mp_obj_t obj_in) {
poll_obj_t *poll_obj = (poll_obj_t *)MP_OBJ_TO_PTR(elem->value);
if (poll_obj->pollfd != NULL) {
poll_obj->pollfd->fd = -1;
--self->poll_set.used;
}
elem->value = MP_OBJ_NULL;
}

View File

@ -77,7 +77,26 @@ try:
except OSError as er:
print("OSError", er.errno)
# Register then unregister a socket (a native stream), then test
# that the Python object is still pollable.
s2 = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
x.poll_state = _MP_STREAM_POLL_RD
poller.register(s2)
poller.unregister(s2)
print_poll_output(poller.poll())
# Test registering and unregistering multiple times.
for _ in range(2):
poller.unregister(s)
poller.unregister(x)
poller.register(s2)
poller.register(s, select.POLLIN)
poller.register(x, select.POLLIN)
poller.unregister(s2)
print_poll_output(poller.poll())
# Clean up.
poller.unregister(x)
poller.unregister(s)
s2.close()
s.close()

View File

@ -9,3 +9,9 @@ CustomPollable.ioctl 3 1
[(<class 'CustomPollable'>, 1)]
CustomPollable.ioctl 3 1
OSError 1000
CustomPollable.ioctl 3 1
[(<class 'CustomPollable'>, 1)]
CustomPollable.ioctl 3 1
[(<class 'CustomPollable'>, 1)]
CustomPollable.ioctl 3 1
[(<class 'CustomPollable'>, 1)]