Messages in this thread | | | Date | Fri, 24 Nov 2006 14:01:44 +0300 | From | Evgeniy Polyakov <> | Subject | Re: [take25 1/6] kevent: Description. |
| |
On Thu, Nov 23, 2006 at 11:45:36AM -0800, Ulrich Drepper (drepper@redhat.com) wrote: > Evgeniy Polyakov wrote: > >Kernel does not put there a new entry, it is only done inside > >kevent_wait(). Entries are put into queue (in any context), where they can > >be obtained > >from only kevent_wait() or kevent_get_events(). > > I know this is how it's done now. But it is not where it has to end. > IMO we have to get to a solution where new events are posted to the ring > buffer asynchronously, i.e., without a thread calling kevent_wait. And > then you need the extra parameter and verification. Even if it's today > not needed we have to future-proof the interface since it cannot be > changed once in use.
There is a special flag in kevent_user to wake it if there are no ready events - kernel thread which has added new events will set it and thus subsequent kevent_wait() will return with updated indexes - userspace must check indexes after kevent_wait().
> -- > ➧ Ulrich Drepper ➧ Red Hat, Inc. ➧ 444 Castro St ➧ Mountain View, > CA ❖
-- Evgeniy Polyakov - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |