alsactl: handle disconnection of sound card

Once sound card becomes disconnection state, corresponding control node
becomes to emit error event for listeners. When catching this type of
event, event dispatcher should stop observation of the node. However,
at present, a mode of monitor can't handle this correctly. As a result,
poll(2) is executed quite frequently in loop with no wait. This results
100% consumption of CPU time.

This commit takes the dispatcher to remove the node from observation
list when detecting the disconnection state.

Reported-by: Thomas Gläßle <thomas@coldfix.de>
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
This commit is contained in:
Takashi Sakamoto 2018-10-14 23:36:32 +09:00 committed by Jaroslav Kysela
parent af14a2fab0
commit 440ea7d38d

View file

@ -285,6 +285,10 @@ static int run_dispatcher(int epfd, struct list_head *srcs)
struct src_entry *entry = (struct src_entry *)ev->data.ptr; struct src_entry *entry = (struct src_entry *)ev->data.ptr;
if (ev->events & EPOLLIN) if (ev->events & EPOLLIN)
print_event(entry->handle, entry->name); print_event(entry->handle, entry->name);
if (ev->events & EPOLLERR) {
operate_dispatcher(epfd, EPOLL_CTL_DEL, NULL, entry);
remove_source_entry(entry);
}
} }
} }