CVSROOT: /cvs
Module name: src
Changes by: [email protected] 2021/01/16 22:56:32
Modified files:
sys/kern : kern_event.c
sys/sys : event.h eventvar.h
Log message:
kqueue: Revise fd close notification
Deliver file descriptor close notification for __EV_POLL knotes through
struct kevent that kqueue_scan() returns. This replaces the previous way
of returning EBADF from kqueue_scan(), making it easier to determine
what exactly has changed.
When a file descriptor is closed, its __EV_POLL knotes are turned into
one-shot events and queued for delivery. These knotes are "unregistered"
as they are reachable only through the queue of active events. This
reduces interference with the normal workings of kqueue. However, more
care is needed to avoid leaking knotes. In addition, the unregistering
removes a limit on the number of issued knotes. To prevent accumulation
of pending fd close notifications, kqpoll_init() flushes the active
queue at the start of a kqpoll scan.
OK mpi@
