static void basic_do_promote(grpc_exec_ctx *exec_ctx, void *args, int success) {
grpc_unary_promote_args *up_args = args;
const grpc_pollset_vtable *original_vtable = up_args->original_vtable;
grpc_pollset *pollset = up_args->pollset;
grpc_fd *fd = up_args->fd;
/*
* This is quite tricky. There are a number of cases to keep in mind here:
* 1. fd may have been orphaned
* 2. The pollset may no longer be a unary poller (and we can't let case #1
* leak to other pollset types!)
* 3. pollset's fd (which may have changed) may have been orphaned
* 4. The pollset may be shutting down.
*/
gpr_mu_lock(&pollset->mu);
/* First we need to ensure that nobody is polling concurrently */
GPR_ASSERT(!grpc_pollset_has_workers(pollset));
gpr_free(up_args);
/* At this point the pollset may no longer be a unary poller. In that case
* we should just call the right add function and be done. */
/* TODO(klempner): If we're not careful this could cause infinite recursion.
* That's not a problem for now because empty_pollset has a trivial poller
* and we don't have any mechanism to unbecome multipoller. */
pollset->in_flight_cbs--;
if (pollset->shutting_down) {
/* We don't care about this pollset anymore. */
if (pollset->in_flight_cbs == 0 && !pollset->called_shutdown) {
finish_shutdown(exec_ctx, pollset);
}
} else if (grpc_fd_is_orphaned(fd)) {
/* Don't try to add it to anything, we'll drop our ref on it below */
} else if (pollset->vtable != original_vtable) {
pollset->vtable->add_fd(exec_ctx, pollset, fd, 0);
} else if (fd != pollset->data.ptr) {
grpc_fd *fds[2];
fds[0] = pollset->data.ptr;
fds[1] = fd;
if (fds[0] && !grpc_fd_is_orphaned(fds[0])) {
grpc_platform_become_multipoller(exec_ctx, pollset, fds,
GPR_ARRAY_SIZE(fds));
GRPC_FD_UNREF(fds[0], "basicpoll");
} else {
/* old fd is orphaned and we haven't cleaned it up until now, so remain a
* unary poller */
/* Note that it is possible that fds[1] is also orphaned at this point.
* That's okay, we'll correct it at the next add or poll. */
if (fds[0]) GRPC_FD_UNREF(fds[0], "basicpoll");
pollset->data.ptr = fd;
GRPC_FD_REF(fd, "basicpoll");
}
}
gpr_mu_unlock(&pollset->mu);
/* Matching ref in basic_pollset_add_fd */
GRPC_FD_UNREF(fd, "basicpoll_add");
}
static void basic_pollset_add_fd(grpc_exec_ctx *exec_ctx, grpc_pollset *pollset,
grpc_fd *fd, int and_unlock_pollset) {
grpc_unary_promote_args *up_args;
GPR_ASSERT(fd);
if (fd == pollset->data.ptr) goto exit;
if (!grpc_pollset_has_workers(pollset)) {
/* Fast path -- no in flight cbs */
/* TODO(klempner): Comment this out and fix any test failures or establish
* they are due to timing issues */
grpc_fd *fds[2];
fds[0] = pollset->data.ptr;
fds[1] = fd;
if (fds[0] == NULL) {
pollset->data.ptr = fd;
GRPC_FD_REF(fd, "basicpoll");
} else if (!grpc_fd_is_orphaned(fds[0])) {
grpc_platform_become_multipoller(exec_ctx, pollset, fds,
GPR_ARRAY_SIZE(fds));
GRPC_FD_UNREF(fds[0], "basicpoll");
} else {
/* old fd is orphaned and we haven't cleaned it up until now, so remain a
* unary poller */
GRPC_FD_UNREF(fds[0], "basicpoll");
pollset->data.ptr = fd;
GRPC_FD_REF(fd, "basicpoll");
}
goto exit;
}
/* Now we need to promote. This needs to happen when we're not polling. Since
* this may be called from poll, the wait needs to happen asynchronously. */
GRPC_FD_REF(fd, "basicpoll_add");
pollset->in_flight_cbs++;
up_args = gpr_malloc(sizeof(*up_args));
up_args->fd = fd;
up_args->original_vtable = pollset->vtable;
up_args->pollset = pollset;
up_args->promotion_closure.cb = basic_do_promote;
up_args->promotion_closure.cb_arg = up_args;
grpc_closure_list_add(&pollset->idle_jobs, &up_args->promotion_closure, 1);
grpc_pollset_kick(pollset, GRPC_POLLSET_KICK_BROADCAST);
exit:
if (and_unlock_pollset) {
gpr_mu_unlock(&pollset->mu);
}
}
