Re: [libvirt] [PATCH] events: Propose a separate lock for event queue

Currently, push& pop from event queue (both server& client side) rely on lock from higher levels, e.g. on driver lock (qemu), private_data (remote), ...; This alone is not sufficient as not every function that interacts with this queue can/does lock, esp. in client where we have a different approach, "passing the buck". Therefore we need a separate lock just to protect event queue. For more info see: https://bugzilla.redhat.com/show_bug.cgi?id=743817 --- src/conf/domain_event.c | 65 +++++++++++++++++++++++++++++++++++++++++------ src/conf/domain_event.h | 1 + 2 files changed, 58 insertions(+), 8 deletions(-)

diff --git a/src/conf/domain_event.c b/src/conf/domain_event.c index 3189346..6cc8168 100644 --- a/src/conf/domain_event.c +++ b/src/conf/domain_event.c @@ -547,6 +547,24 @@ virDomainEventQueuePtr virDomainEventQueueNew(void) return ret; } +static void +virDomainEventStateLock(virDomainEventStatePtr state) +{ + if (!state) + return; + + virMutexLock(&state->lock);

@@ -1161,18 +1188,26 @@ void virDomainEventStateQueue(virDomainEventStatePtr state, virDomainEventPtr event) { + int count; + if (state->timer< 0) { virDomainEventFree(event); return; } + virDomainEventStateLock(state); + if (virDomainEventQueuePush(state->queue, event)< 0) { VIR_DEBUG("Error adding event to queue"); virDomainEventFree(event); } - if (state->queue->count == 1) + count = state->queue->count; + virDomainEventStateUnlock(state);