On 01.03.2013 11:45, Daniel P. Berrange wrote:
On Fri, Mar 01, 2013 at 11:36:24AM +0100, Michal Privoznik wrote:
Currently, after we removed the qemu driver lock, it may happen that two or more threads will start up a machine with macvlan and race over virNetDevMacVLanCreateWithVPortProfile(). However, there's a racy section in which we are generating a sequence of possible device names and detecting if they exits. If we found one which doesn't we try to create a device with that name. However, the other thread is doing just the same. Assume it will succeed and we must therefore fail. If this happens more than 5 times (which in massive parallel startup surely will) we return -1 without any error reported. This patch is a simple hack to both of these problems. It introduces a mutex, so only one thread will enter the section, and if it runs out of possibilities, error is reported. Moreover, the number of retries is raised to 20. ---
diff to v1: -don't increase @retries -move error reporting to virNetDevMacVLanCreateMutexOnceInit
src/util/virnetdevmacvlan.c | 37 ++++++++++++++++++++++++++++++++----- 1 file changed, 32 insertions(+), 5 deletions(-)
ACK
Daniel
Thanks, pushed. Michal