diff options
Diffstat (limited to 'lib/thread.c')
| -rw-r--r-- | lib/thread.c | 34 |
1 files changed, 26 insertions, 8 deletions
diff --git a/lib/thread.c b/lib/thread.c index 7489be5c2d..2e7b0ca0ef 100644 --- a/lib/thread.c +++ b/lib/thread.c @@ -1238,12 +1238,31 @@ static struct thread *thread_run(struct thread_master *m, struct thread *thread, } static int thread_process_io_helper(struct thread_master *m, - struct thread *thread, short state, int pos) + struct thread *thread, short state, + short actual_state, int pos) { struct thread **thread_array; - if (!thread) + /* + * poll() clears the .events field, but the pollfd array we + * pass to poll() is a copy of the one used to schedule threads. + * We need to synchronize state between the two here by applying + * the same changes poll() made on the copy of the "real" pollfd + * array. + * + * This cleans up a possible infinite loop where we refuse + * to respond to a poll event but poll is insistent that + * we should. + */ + m->handler.pfds[pos].events &= ~(state); + + if (!thread) { + if ((actual_state & (POLLHUP|POLLIN)) != POLLHUP) + flog_err(EC_LIB_NO_THREAD, + "Attempting to process an I/O event but for fd: %d(%d) no thread to handle this!\n", + m->handler.pfds[pos].fd, actual_state); return 0; + } if (thread->type == THREAD_READ) thread_array = m->read; @@ -1253,9 +1272,7 @@ static int thread_process_io_helper(struct thread_master *m, thread_array[thread->u.fd] = NULL; thread_list_add_tail(&m->ready, thread); thread->type = THREAD_READY; - /* if another pthread scheduled this file descriptor for the event we're - * responding to, no problem; we're getting to it now */ - thread->master->handler.pfds[pos].events &= ~(state); + return 1; } @@ -1291,12 +1308,13 @@ static void thread_process_io(struct thread_master *m, unsigned int num) * there's no need to update it. Similarily, barring deletion, * the fd * should still be a valid index into the master's pfds. */ - if (pfds[i].revents & (POLLIN | POLLHUP)) + if (pfds[i].revents & (POLLIN | POLLHUP)) { thread_process_io_helper(m, m->read[pfds[i].fd], POLLIN, - i); + pfds[i].revents, i); + } if (pfds[i].revents & POLLOUT) thread_process_io_helper(m, m->write[pfds[i].fd], - POLLOUT, i); + POLLOUT, pfds[i].revents, i); /* if one of our file descriptors is garbage, remove the same * from |