[RFC] Timer: Set EPOLLONESHOT for EPOLL_CTL_ADD after knote creation #10
Conversation
ianpartridge
force-pushed
the
timer-oneshot
branch
from
5408d7a
to
ea35db4
Compare
|
Hi Ian, Thanks for the patch! Just to let you know, I am a few weeks away from hitting a deadline on different project, and then I'm going out of town, so I can't take the time to test this out. I will get back to you by the end of June. Sorry for the delay,
|
ianpartridge
force-pushed
the
timer-oneshot
branch
from
ea35db4
to
8f7aab8
Compare
| @@ -151,7 +151,10 @@ evfilt_timer_knote_create(struct filter *filt, struct knote *kn) | |||
| } | |||
|
|
|||
| memset(&ev, 0, sizeof(ev)); | |||
| ev.events = EPOLLIN; | |||
| ev.events = EPOLLIN | EPOLLET; | |||
| if (kn->kev.flags & EV_ONESHOT || kn->kev.flags & EV_DISPATCH) | |||
There was a problem hiding this comment.
that seems wrong because of priority of operators in C. you should write this:
if (kn->kev.flags & (EV_ONESHOT | EV_DISPATCH))
There was a problem hiding this comment.
if ((kn->kev.flags & EV_ONESHOT) || (kn->kev.flags & EV_DISPATCH))
is the desired logic.
There was a problem hiding this comment.
I know, and it's completely equivalent to if (kn->kev.flags & (EV_ONESHOT | EV_DISPATCH)) ;)
but adding the parens also fixes it indeed
There was a problem hiding this comment.
Thanks! PR updated.
ianpartridge
force-pushed
the
timer-oneshot
branch
from
8f7aab8
to
4094aeb
Compare
When using libkqueue, I see
knote.c:153: knote_disable: Assertion '!(kn->kev.flags & 0x0008)' failed.(EV_DISABLE set twice on the same knote).This patch ensures that
EPOLLONESHOTis set on the ev.events if we are processing anEV_ONESHOTorEV_DISPATCHtimer kevent. There is similar logic already in linux/write.c and linux/read.cThe patch resolves the assertion I am seeing. Comments very welcome as I am new to libkqueue. Thank you.