[libvirt] [PATCH] qemu_driver: fix setting vcpus for offline domain
Commit e3435caf fixed hot-plugging of vcpus with strict memory pinning on NUMA hosts, but unfortunately it also broke updating number of vcpus for offline guests using our API. The issue is that we try to create a cpu cgroup for non-running guest which fails as there are no cgroups for that domain. We should create cgroups and update cpuset.mems only if we are hot-plugging. Signed-off-by: Pavel Hrdina <phrdina@redhat.com> --- src/qemu/qemu_driver.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index cdf4173..3a343d0 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4576,21 +4576,23 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus, priv = vm->privateData; - if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) - goto cleanup; - - if (!(all_nodes = virNumaGetHostNodeset())) - goto cleanup; - - if (!(all_nodes_str = virBitmapFormat(all_nodes))) - goto cleanup; - if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) goto cleanup; - if (virCgroupGetCpusetMems(cgroup_temp, &mem_mask) < 0 || - virCgroupSetCpusetMems(cgroup_temp, all_nodes_str) < 0) - goto endjob; + if (flags & VIR_DOMAIN_AFFECT_LIVE) { + if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) + goto cleanup; + + if (!(all_nodes = virNumaGetHostNodeset())) + goto cleanup; + + if (!(all_nodes_str = virBitmapFormat(all_nodes))) + goto cleanup; + + if (virCgroupGetCpusetMems(cgroup_temp, &mem_mask) < 0 || + virCgroupSetCpusetMems(cgroup_temp, all_nodes_str) < 0) + goto endjob; + } maximum = (flags & VIR_DOMAIN_VCPU_MAXIMUM) != 0; flags &= ~VIR_DOMAIN_VCPU_MAXIMUM; -- 2.0.5
On Tue, Jan 13, 2015 at 02:46:03PM +0100, Pavel Hrdina wrote:
Commit e3435caf fixed hot-plugging of vcpus with strict memory pinning on NUMA hosts, but unfortunately it also broke updating number of vcpus for offline guests using our API.
The issue is that we try to create a cpu cgroup for non-running guest which fails as there are no cgroups for that domain. We should create cgroups and update cpuset.mems only if we are hot-plugging.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com> --- src/qemu/qemu_driver.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index cdf4173..3a343d0 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4576,21 +4576,23 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
priv = vm->privateData;
- if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) - goto cleanup; - - if (!(all_nodes = virNumaGetHostNodeset())) - goto cleanup; - - if (!(all_nodes_str = virBitmapFormat(all_nodes))) - goto cleanup; - if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) goto cleanup;
- if (virCgroupGetCpusetMems(cgroup_temp, &mem_mask) < 0 || - virCgroupSetCpusetMems(cgroup_temp, all_nodes_str) < 0) - goto endjob; + if (flags & VIR_DOMAIN_AFFECT_LIVE) {
As we are also doing the guest agent cpu config stuff in this function and the cgroup stuff isn't required for that operation please add && !(flags & VIR_DOMAIN_VCPU_GUEST) to the condition.
+ if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) + goto cleanup; + + if (!(all_nodes = virNumaGetHostNodeset())) + goto cleanup; + + if (!(all_nodes_str = virBitmapFormat(all_nodes))) + goto cleanup; + + if (virCgroupGetCpusetMems(cgroup_temp, &mem_mask) < 0 || + virCgroupSetCpusetMems(cgroup_temp, all_nodes_str) < 0) + goto endjob; + }
maximum = (flags & VIR_DOMAIN_VCPU_MAXIMUM) != 0; flags &= ~VIR_DOMAIN_VCPU_MAXIMUM;
ACK with the addition. Peter
On 01/14/2015 10:23 AM, Peter Krempa wrote:
On Tue, Jan 13, 2015 at 02:46:03PM +0100, Pavel Hrdina wrote:
Commit e3435caf fixed hot-plugging of vcpus with strict memory pinning on NUMA hosts, but unfortunately it also broke updating number of vcpus for offline guests using our API.
The issue is that we try to create a cpu cgroup for non-running guest which fails as there are no cgroups for that domain. We should create cgroups and update cpuset.mems only if we are hot-plugging.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com> --- src/qemu/qemu_driver.c | 26 ++++++++++++++------------ 1 file changed, 14 insertions(+), 12 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index cdf4173..3a343d0 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4576,21 +4576,23 @@ qemuDomainSetVcpusFlags(virDomainPtr dom, unsigned int nvcpus,
priv = vm->privateData;
- if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) - goto cleanup; - - if (!(all_nodes = virNumaGetHostNodeset())) - goto cleanup; - - if (!(all_nodes_str = virBitmapFormat(all_nodes))) - goto cleanup; - if (qemuDomainObjBeginJob(driver, vm, QEMU_JOB_MODIFY) < 0) goto cleanup;
- if (virCgroupGetCpusetMems(cgroup_temp, &mem_mask) < 0 || - virCgroupSetCpusetMems(cgroup_temp, all_nodes_str) < 0) - goto endjob; + if (flags & VIR_DOMAIN_AFFECT_LIVE) {
As we are also doing the guest agent cpu config stuff in this function and the cgroup stuff isn't required for that operation please add
&& !(flags & VIR_DOMAIN_VCPU_GUEST)
to the condition.
+ if (virCgroupNewEmulator(priv->cgroup, false, &cgroup_temp) < 0) + goto cleanup; + + if (!(all_nodes = virNumaGetHostNodeset())) + goto cleanup; + + if (!(all_nodes_str = virBitmapFormat(all_nodes))) + goto cleanup; + + if (virCgroupGetCpusetMems(cgroup_temp, &mem_mask) < 0 || + virCgroupSetCpusetMems(cgroup_temp, all_nodes_str) < 0) + goto endjob; + }
maximum = (flags & VIR_DOMAIN_VCPU_MAXIMUM) != 0; flags &= ~VIR_DOMAIN_VCPU_MAXIMUM;
ACK with the addition.
Peter
Thanks, I'll push it shortly. Pavel
participants (2)
-
Pavel Hrdina -
Peter Krempa