[libvirt] [RFC PATCH 12/12] qemu_driver: detect threads corresponding to Vcpus
Zhu Guihua
zhugh.fnst at cn.fujitsu.com
Wed Jan 21 08:01:04 UTC 2015
After hotplugging the CPUs, we need to re-detect threads corresponding to Vcpus.
Signed-off-by: Zhu Guihua <zhugh.fnst at cn.fujitsu.com>
---
src/qemu/qemu_driver.c | 271 ++++++++++++++++++++++++------------------------
src/qemu/qemu_driver.h | 8 ++
src/qemu/qemu_hotplug.c | 7 ++
3 files changed, 152 insertions(+), 134 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 004bc35..09ac088 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -4357,89 +4357,49 @@ static void qemuProcessEventHandler(void *data, void *opaque)
VIR_FREE(processEvent);
}
-static int qemuDomainHotplugVcpus(virQEMUDriverPtr driver,
- virDomainObjPtr vm,
- unsigned int nvcpus)
+/* After hotplugging the CPUs we need to re-detect threads corresponding
+ * * to the virtual CPUs. Some older versions don't provide the thread ID
+ * * or don't have the "info cpus" command (and they don't support multiple
+ * * CPUs anyways), so errors in the re-detection will not be treated
+ * * fatal */
+int
+qemuDomainDetectVcpu(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ int apic_id,
+ bool plug)
{
qemuDomainObjPrivatePtr priv = vm->privateData;
- size_t i;
- int rc = 1;
- int ret = -1;
int oldvcpus = vm->def->vcpus;
int vcpus = oldvcpus;
pid_t *cpupids = NULL;
int ncpupids;
+ int ret = -1;
virCgroupPtr cgroup_vcpu = NULL;
char *mem_mask = NULL;
- uint32_t apic_id;
-
- qemuDomainObjEnterMonitor(driver, vm);
-
- /* We need different branches here, because we want to offline
- * in reverse order to onlining, so any partial fail leaves us in a
- * reasonably sensible state */
- if (nvcpus > vcpus) {
- for (i = vcpus; i < nvcpus; i++) {
- /* Online new CPU */
- apic_id = virDomainCPUGetFreeApicID(vm->def);
- rc = qemuMonitorSetCPU(priv->mon, apic_id, true);
- if (rc == 0)
- goto unsupported;
- if (rc < 0)
- goto exit_monitor;
-
- vcpus++;
- ignore_value(virBitmapSetBit(vm->def->apic_id_map, apic_id));
- }
- } else {
- for (i = vcpus - 1; i >= nvcpus; i--) {
- /* Offline old CPU */
- rc = qemuMonitorSetCPU(priv->mon, i, false);
- if (rc == 0)
- goto unsupported;
- if (rc < 0)
- goto exit_monitor;
-
- vcpus--;
- }
- }
-
- /* hotplug succeeded */
+ int idx = 0;
+ size_t i;
+ int *thread = NULL;
ret = 0;
+ if (plug)
+ vcpus++;
+ else
+ vcpus--;
+
+ qemuDomainObjEnterMonitor(driver, vm);
- /* After hotplugging the CPUs we need to re-detect threads corresponding
- * to the virtual CPUs. Some older versions don't provide the thread ID
- * or don't have the "info cpus" command (and they don't support multiple
- * CPUs anyways), so errors in the re-detection will not be treated
- * fatal */
- if ((ncpupids = qemuMonitorGetCPUInfo(priv->mon, &cpupids)) <= 0) {
+ if ((ncpupids = qemuMonitorGetCPUInfo(priv->mon, &cpupids)) <= 0){
virResetLastError();
- goto exit_monitor;
- }
- if (qemuDomainObjExitMonitor(driver, vm) < 0) {
- ret = -1;
goto cleanup;
}
- /* check if hotplug has failed */
- if (vcpus < oldvcpus && ncpupids == oldvcpus) {
- virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
- _("qemu didn't unplug the vCPUs properly"));
- vcpus = oldvcpus;
- ret = -1;
- goto cleanup;
+ for (i = 0; i < apic_id; i++) {
+ if (virBitmapIsSet(vm->def->apic_id_map, i))
+ idx++;
}
- if (ncpupids != vcpus) {
- virReportError(VIR_ERR_INTERNAL_ERROR,
- _("got wrong number of vCPU pids from QEMU monitor. "
- "got %d, wanted %d"),
- ncpupids, vcpus);
- vcpus = oldvcpus;
- ret = -1;
+ if (VIR_ALLOC_N(thread, vcpus) < 0)
goto cleanup;
- }
if (virDomainNumatuneGetMode(vm->def->numatune, -1) ==
VIR_DOMAIN_NUMATUNE_MEM_STRICT &&
@@ -4448,105 +4408,148 @@ static int qemuDomainHotplugVcpus(virQEMUDriverPtr driver,
&mem_mask, -1) < 0)
goto cleanup;
- if (nvcpus > oldvcpus) {
- for (i = oldvcpus; i < nvcpus; i++) {
- if (priv->cgroup) {
- int rv = -1;
- /* Create cgroup for the onlined vcpu */
- if (virCgroupNewVcpu(priv->cgroup, i, true, &cgroup_vcpu) < 0)
- goto cleanup;
-
- if (mem_mask &&
- virCgroupSetCpusetMems(cgroup_vcpu, mem_mask) < 0)
- goto cleanup;
+ if (vcpus > oldvcpus) {
+ if (priv->cgroup) {
+ int rv = -1;
+ if (virCgroupNewVcpu(priv->cgroup, apic_id, true, &cgroup_vcpu) < 0)
+ goto cleanup;
- /* Add vcpu thread to the cgroup */
- rv = virCgroupAddTask(cgroup_vcpu, cpupids[i]);
- if (rv < 0) {
- virReportSystemError(-rv,
- _("unable to add vcpu %zu task %d to cgroup"),
- i, cpupids[i]);
- virCgroupRemove(cgroup_vcpu);
- goto cleanup;
- }
+ if (mem_mask &&
+ virCgroupSetCpusetMems(cgroup_vcpu, mem_mask) < 0)
+ goto cleanup;
+ rv = virCgroupAddTask(cgroup_vcpu, cpupids[idx]);
+ if (rv < 0) {
+ virReportSystemError(-rv,
+ _("unable to add vcpu %d task %d to cgroup"),
+ apic_id, cpupids[idx]);
+ virCgroupRemove(cgroup_vcpu);
+ goto cleanup;
}
+ }
- /* Inherit def->cpuset */
- if (vm->def->cpumask) {
- /* vm->def->cputune.vcpupin can't be NULL if
- * vm->def->cpumask is not NULL.
- */
- virDomainVcpuPinDefPtr vcpupin = NULL;
+ if (vm->def->cpumask) {
+ virDomainVcpuPinDefPtr vcpupin = NULL;
- if (VIR_ALLOC(vcpupin) < 0)
- goto cleanup;
+ if (VIR_ALLOC(vcpupin) < 0)
+ goto cleanup;
- vcpupin->cpumask = virBitmapNew(VIR_DOMAIN_CPUMASK_LEN);
- virBitmapCopy(vcpupin->cpumask, vm->def->cpumask);
- vcpupin->vcpuid = i;
- if (VIR_APPEND_ELEMENT_COPY(vm->def->cputune.vcpupin,
- vm->def->cputune.nvcpupin, vcpupin) < 0) {
- virBitmapFree(vcpupin->cpumask);
- VIR_FREE(vcpupin);
+ vcpupin->cpumask = virBitmapNew(VIR_DOMAIN_CPUMASK_LEN);
+ virBitmapCopy(vcpupin->cpumask, vm->def->cpumask);
+ vcpupin->vcpuid = apic_id;
+ if (VIR_APPEND_ELEMENT_COPY(vm->def->cputune.vcpupin,
+ vm->def->cputune.nvcpupin, vcpupin) < 0) {
+ virBitmapFree(vcpupin->cpumask);
+ VIR_FREE(vcpupin);
+ ret = -1;
+ goto cleanup;
+ }
+
+ if (cgroup_vcpu) {
+ if (qemuSetupCgroupVcpuPin(cgroup_vcpu,
+ vm->def->cputune.vcpupin,
+ vm->def->cputune.nvcpupin, apic_id) < 0) {
+ virReportError(VIR_ERR_OPERATION_INVALID,
+ _("failed to set cpuset.cpus in cgroup"
+ " for vcpu %d"), apic_id);
ret = -1;
goto cleanup;
}
-
- if (cgroup_vcpu) {
- if (qemuSetupCgroupVcpuPin(cgroup_vcpu,
- vm->def->cputune.vcpupin,
- vm->def->cputune.nvcpupin, i) < 0) {
- virReportError(VIR_ERR_OPERATION_INVALID,
- _("failed to set cpuset.cpus in cgroup"
- " for vcpu %zu"), i);
- ret = -1;
- goto cleanup;
- }
- } else {
- if (virProcessSetAffinity(cpupids[i],
- vcpupin->cpumask) < 0) {
- virReportError(VIR_ERR_SYSTEM_ERROR,
- _("failed to set cpu affinity for vcpu %zu"),
- i);
- ret = -1;
- goto cleanup;
- }
+ } else {
+ if (virProcessSetAffinity(cpupids[idx],
+ vcpupin->cpumask) < 0) {
+ virReportError(VIR_ERR_SYSTEM_ERROR,
+ _("failed to set cpu affinity for vcpu %d"),
+ apic_id);
+ ret = -1;
+ goto cleanup;
}
}
virCgroupFree(&cgroup_vcpu);
}
} else {
- for (i = oldvcpus - 1; i >= nvcpus; i--) {
- if (priv->cgroup) {
- if (virCgroupNewVcpu(priv->cgroup, i, false, &cgroup_vcpu) < 0)
- goto cleanup;
-
- /* Remove cgroup for the offlined vcpu */
- virCgroupRemove(cgroup_vcpu);
- virCgroupFree(&cgroup_vcpu);
- }
+ if (priv->cgroup) {
+ if (virCgroupNewVcpu(priv->cgroup, apic_id, false, &cgroup_vcpu) < 0)
+ goto cleanup;
- /* Free vcpupin setting */
- virDomainVcpuPinDel(vm->def, i);
+ virCgroupRemove(cgroup_vcpu);
+ virCgroupFree(&cgroup_vcpu);
}
+
+ virDomainVcpuPinDel(vm->def, apic_id);
}
priv->nvcpupids = ncpupids;
VIR_FREE(priv->vcpupids);
priv->vcpupids = cpupids;
cpupids = NULL;
+ thread = NULL;
cleanup:
+ qemuDomainObjExitMonitor(driver, vm);
+ vm->def->vcpus = vcpus;
VIR_FREE(cpupids);
+ VIR_FREE(thread);
VIR_FREE(mem_mask);
- if (virDomainObjIsActive(vm))
- vm->def->vcpus = vcpus;
- virDomainAuditVcpu(vm, oldvcpus, nvcpus, "update", rc == 1);
+ virDomainAuditVcpu(vm, oldvcpus, vcpus, "update", true);
if (cgroup_vcpu)
virCgroupFree(&cgroup_vcpu);
return ret;
+}
+
+static int qemuDomainHotplugVcpus(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ unsigned int nvcpus)
+{
+ qemuDomainObjPrivatePtr priv = vm->privateData;
+ size_t i;
+ int rc = 1;
+ int ret = -1;
+ int oldvcpus = vm->def->vcpus;
+ int vcpus = oldvcpus;
+ uint32_t apic_id;
+
+ /* We need different branches here, because we want to offline
+ * in reverse order to onlining, so any partial fail leaves us in a
+ * reasonably sensible state */
+ if (nvcpus > vcpus) {
+ for (i = vcpus; i < nvcpus; i++) {
+ /* Online new CPU */
+ qemuDomainObjEnterMonitor(driver, vm);
+ apic_id = virDomainCPUGetFreeApicID(vm->def);
+ rc = qemuMonitorSetCPU(priv->mon, apic_id, true);
+ if (rc == 0)
+ goto unsupported;
+ if (rc < 0)
+ goto exit_monitor;
+
+ qemuDomainObjExitMonitor(driver, vm);
+ vcpus++;
+ ignore_value(virBitmapSetBit(vm->def->apic_id_map, apic_id));
+
+ if (qemuDomainDetectVcpu(driver, vm, apic_id, true) < 0)
+ goto cleanup;
+ }
+ } else {
+ for (i = vcpus - 1; i >= nvcpus; i--) {
+ /* Offline old CPU */
+ rc = qemuMonitorSetCPU(priv->mon, i, false);
+ if (rc == 0)
+ goto unsupported;
+ if (rc < 0)
+ goto exit_monitor;
+
+ vcpus--;
+ }
+ }
+
+ /* hotplug succeeded */
+
+ ret = 0;
+
+ cleanup:
+ return ret;
unsupported:
virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
diff --git a/src/qemu/qemu_driver.h b/src/qemu/qemu_driver.h
index df7533a..55ce618 100644
--- a/src/qemu/qemu_driver.h
+++ b/src/qemu/qemu_driver.h
@@ -20,10 +20,18 @@
*
* Author: Daniel P. Berrange <berrange at redhat.com>
*/
+#include "qemu_conf.h"
+#include "domain_conf.h"
#ifndef __QEMU_DRIVER_H__
# define __QEMU_DRIVER_H__
int qemuRegister(void);
+int
+qemuDomainDetectVcpu(virQEMUDriverPtr driver,
+ virDomainObjPtr vm,
+ int apic_id,
+ bool plug);
+
#endif /* __QEMU_DRIVER_H__ */
diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c
index 41013d9..8a20304 100644
--- a/src/qemu/qemu_hotplug.c
+++ b/src/qemu/qemu_hotplug.c
@@ -31,6 +31,7 @@
#include "qemu_command.h"
#include "qemu_hostdev.h"
#include "qemu_interface.h"
+#include "qemu_driver.h"
#include "domain_audit.h"
#include "netdev_bandwidth_conf.h"
#include "domain_nwfilter.h"
@@ -1591,6 +1592,9 @@ int qemuDomainAttachCPUDevice(virQEMUDriverPtr driver,
ignore_value(virBitmapSetBit(vm->def->apic_id_map, cpu->apic_id));
ret = 0;
+ if (qemuDomainDetectVcpu(driver, vm, cpu->apic_id, true) < 0)
+ ret = -1;
+
cleanup:
VIR_FREE(devstr);
return ret;
@@ -3903,6 +3907,9 @@ int qemuDomainDetachCPUDevice(virQEMUDriverPtr driver,
else
goto cleanup;
+ if (qemuDomainDetectVcpu(driver, vm, tmpCPU->apic_id, false) < 0)
+ ret = -1;
+
cleanup:
qemuDomainResetDeviceRemoval(vm);
return ret;
--
1.9.3
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