From f229a55c31a7e12a15c7b4dcf9a97a9bf7a72ce8 Mon Sep 17 00:00:00 2001 From: "Michael S. Tsirkin" Date: Thu, 26 Oct 2017 04:48:01 +0300 Subject: virtio/ringtest: fix up need_event math last kicked event index must be updated unconditionally: even if we don't need to kick, we do not want to re-check the same entry for events. Signed-off-by: Michael S. Tsirkin Acked-by: Cornelia Huck Acked-by: Jason Wang --- tools/virtio/ringtest/ring.c | 24 +++++++++++++++--------- 1 file changed, 15 insertions(+), 9 deletions(-) (limited to 'tools/virtio') diff --git a/tools/virtio/ringtest/ring.c b/tools/virtio/ringtest/ring.c index 747c5dd47be8..2b9859beea65 100644 --- a/tools/virtio/ringtest/ring.c +++ b/tools/virtio/ringtest/ring.c @@ -188,16 +188,18 @@ bool enable_call() void kick_available(void) { + bool need; + /* Flush in previous flags write */ /* Barrier C (for pairing) */ smp_mb(); - if (!need_event(event->kick_index, - guest.avail_idx, - guest.kicked_avail_idx)) - return; + need = need_event(event->kick_index, + guest.avail_idx, + guest.kicked_avail_idx); guest.kicked_avail_idx = guest.avail_idx; - kick(); + if (need) + kick(); } /* host side */ @@ -253,14 +255,18 @@ bool use_buf(unsigned *lenp, void **bufp) void call_used(void) { + bool need; + /* Flush in previous flags write */ /* Barrier D (for pairing) */ smp_mb(); - if (!need_event(event->call_index, + + need = need_event(event->call_index, host.used_idx, - host.called_used_idx)) - return; + host.called_used_idx); host.called_used_idx = host.used_idx; - call(); + + if (need) + call(); } -- cgit v1.2.3-59-g8ed1b