eventfd - allow atomic read and waitqueue remove
authorDavide Libenzi <davidel@xmailserver.org>
Wed, 13 Jan 2010 17:34:36 +0000 (09:34 -0800)
committerMarcelo Tosatti <mtosatti@redhat.com>
Mon, 25 Jan 2010 14:26:38 +0000 (12:26 -0200)
commitcb289d6244a37cf932c571d6deb0daa8030f931b
tree05bea15a25c9d9a4dcc0658a6a8bf845daca535a
parenta6085fbaf65ab09bfb5ec8d902d6d21680fe1895
eventfd - allow atomic read and waitqueue remove

KVM needs a wait to atomically remove themselves from the eventfd ->poll()
wait queue head, in order to handle correctly their IRQfd deassign
operation.

This patch introduces such API, plus a way to read an eventfd from its
context.

Signed-off-by: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Avi Kivity <avi@redhat.com>
fs/eventfd.c
include/linux/eventfd.h