On Tue, Feb 23, 2016 at 04:58:40PM +0100, Henning Schild wrote:
Move qemuSetupCgroupForEmulator up under qemuSetupCgroup. That way we move the one main thread right into the emulator cgroup, instead of moving multiple threads later on. And we do not actually want any threads running in the parent cgroups (cpu cpuacct cpuset).
Signed-off-by: Henning Schild <henning.schild@siemens.com> --- src/qemu/qemu_process.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
ACK, this is the key part of the fix. With the old code the QEMU pids are only moved /after/ exec(), with this change, the pids are moved /before/ exec(), fixing the core problem of threads runing int the wrong place between 'exec()' and libvirt querying vCPUs.
diff --git a/src/qemu/qemu_process.c b/src/qemu/qemu_process.c index 05cbda2..65f718c 100644 --- a/src/qemu/qemu_process.c +++ b/src/qemu/qemu_process.c @@ -4895,6 +4895,10 @@ qemuProcessLaunch(virConnectPtr conn, if (qemuSetupCgroup(driver, vm, nnicindexes, nicindexes) < 0) goto cleanup;
+ VIR_DEBUG("Setting cgroup for emulator (if required)"); + if (qemuSetupCgroupForEmulator(vm) < 0) + goto cleanup; + /* This must be done after cgroup placement to avoid resetting CPU * affinity */ if (!vm->def->cputune.emulatorpin && @@ -4943,10 +4947,6 @@ qemuProcessLaunch(virConnectPtr conn, if (rv == -1) /* The VM failed to start */ goto cleanup;
- VIR_DEBUG("Setting cgroup for emulator (if required)"); - if (qemuSetupCgroupForEmulator(vm) < 0) - goto cleanup; - VIR_DEBUG("Setting affinity of emulator threads"); if (qemuProcessSetEmulatorAffinity(vm) < 0) goto cleanup; -- 2.4.10
Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|