[libvirt] [PATCH v2.1 21/21] qemu: support of emulator_period and emulator_quota's modification

[Hu Tao]

On Wed, Aug 22, 2012 at 05:04:57PM +0800, Daniel Veillard wrote:
> On Tue, Aug 21, 2012 at 05:18:44PM +0800, Hu Tao wrote:
> > From: Wen Congyang <wency at cn.fujitsu.com>
> > 
> > allow the user change/get emulator's period and quota when the vm is running.
> > ---
> >  src/qemu/qemu_driver.c |  133 +++++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 132 insertions(+), 1 deletion(-)
> > 
> > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
> > index 8314375..0e7dc32 100644
> > --- a/src/qemu/qemu_driver.c
> > +++ b/src/qemu/qemu_driver.c
> > @@ -6603,7 +6603,7 @@ static char *qemuGetSchedulerType(virDomainPtr dom,
> >          else if (rc == 0)
> >              *nparams = 1;
> >          else
> > -            *nparams = 3;
> > +            *nparams = 5;
> >      }
> >  
> >      ret = strdup("posix");
> > @@ -7734,6 +7734,40 @@ cleanup:
> >  }
> >  
> >  static int
> > +qemuSetEmulatorBandwidthLive(virDomainObjPtr vm, virCgroupPtr cgroup,
> > +                             unsigned long long period, long long quota)
> > +{
> > +    qemuDomainObjPrivatePtr priv = vm->privateData;
> > +    virCgroupPtr cgroup_emulator = NULL;
> > +    int rc;
> > +
> > +    if (period == 0 && quota == 0)
> > +        return 0;
> > +
> > +    if (priv->nvcpupids == 0 || priv->vcpupids[0] == vm->pid) {
> > +        return 0;
> > +    }
> > +
> > +    rc = virCgroupForEmulator(cgroup, &cgroup_emulator, 0);
> > +    if (rc < 0) {
> > +        virReportSystemError(-rc,
> > +                             _("Unable to find emulator cgroup for %s"),
> > +                             vm->def->name);
> > +        goto cleanup;
> > +    }
> > +
> > +    if (qemuSetupCgroupVcpuBW(cgroup_emulator, period, quota) < 0)
> > +        goto cleanup;
> > +
> > +    virCgroupFree(&cgroup_emulator);
> > +    return 0;
> > +
> > +cleanup:
> > +    virCgroupFree(&cgroup_emulator);
> > +    return -1;
> > +}
> > +
> > +static int
> >  qemuSetSchedulerParametersFlags(virDomainPtr dom,
> >                                  virTypedParameterPtr params,
> >                                  int nparams,
> > @@ -7756,6 +7790,10 @@ qemuSetSchedulerParametersFlags(virDomainPtr dom,
> >                                         VIR_TYPED_PARAM_ULLONG,
> >                                         VIR_DOMAIN_SCHEDULER_VCPU_QUOTA,
> >                                         VIR_TYPED_PARAM_LLONG,
> > +                                       VIR_DOMAIN_SCHEDULER_EMULATOR_PERIOD,
> > +                                       VIR_TYPED_PARAM_ULLONG,
> > +                                       VIR_DOMAIN_SCHEDULER_EMULATOR_QUOTA,
> > +                                       VIR_TYPED_PARAM_LLONG,
> >                                         NULL) < 0)
> >          return -1;
> >  
> > @@ -7838,6 +7876,32 @@ qemuSetSchedulerParametersFlags(virDomainPtr dom,
> >              if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
> >                  vmdef->cputune.quota = params[i].value.l;
> >              }
> > +        } else if (STREQ(param->field, VIR_DOMAIN_SCHEDULER_EMULATOR_PERIOD)) {
> > +            if (flags & VIR_DOMAIN_AFFECT_LIVE) {
> > +                rc = qemuSetEmulatorBandwidthLive(vm, group, params[i].value.ul, 0);
> > +                if (rc != 0)
> > +                    goto cleanup;
> > +
> > +                if (params[i].value.ul)
> > +                    vm->def->cputune.emulator_period = params[i].value.ul;
> > +            }
> > +
> > +            if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
> > +                vmdef->cputune.emulator_period = params[i].value.ul;
> > +            }
> > +        } else if (STREQ(param->field, VIR_DOMAIN_SCHEDULER_EMULATOR_QUOTA)) {
> > +            if (flags & VIR_DOMAIN_AFFECT_LIVE) {
> > +                rc = qemuSetEmulatorBandwidthLive(vm, group, 0, params[i].value.l);
> > +                if (rc != 0)
> > +                    goto cleanup;
> > +
> > +                if (params[i].value.l)
> > +                    vm->def->cputune.emulator_quota = params[i].value.l;
> > +            }
> > +
> > +            if (flags & VIR_DOMAIN_AFFECT_CONFIG) {
> > +                vmdef->cputune.emulator_quota = params[i].value.l;
> > +            }
> >          }
> >      }
> >  
> > @@ -7942,6 +8006,43 @@ cleanup:
> >  }
> >  
> >  static int
> > +qemuGetEmulatorBandwidthLive(virDomainObjPtr vm, virCgroupPtr cgroup,
> > +                             unsigned long long *period, long long *quota)
> > +{
> > +    virCgroupPtr cgroup_emulator = NULL;
> > +    qemuDomainObjPrivatePtr priv = NULL;
> > +    int rc;
> > +    int ret = -1;
> > +
> > +    priv = vm->privateData;
> > +    if (priv->nvcpupids == 0 || priv->vcpupids[0] == vm->pid) {
> > +        /* We don't create sub dir for each vcpu */
> > +        *period = 0;
> > +        *quota = 0;
> > +        return 0;
> > +    }
> > +
> > +    /* get period and quota for emulator */
> > +    rc = virCgroupForEmulator(cgroup, &cgroup_emulator, 0);
> > +    if (!cgroup_emulator) {
> > +        virReportSystemError(-rc,
> > +                             _("Unable to find emulator cgroup for %s"),
> > +                             vm->def->name);
> > +        goto cleanup;
> > +    }
> > +
> > +    rc = qemuGetVcpuBWLive(cgroup_emulator, period, quota);
> > +    if (rc < 0)
> > +        goto cleanup;
> > +
> > +    ret = 0;
> > +
> > +cleanup:
> > +    virCgroupFree(&cgroup_emulator);
> > +    return ret;
> > +}
> > +
> > +static int
> >  qemuGetSchedulerParametersFlags(virDomainPtr dom,
> >                                  virTypedParameterPtr params,
> >                                  int *nparams,
> > @@ -7953,6 +8054,8 @@ qemuGetSchedulerParametersFlags(virDomainPtr dom,
> >      unsigned long long shares;
> >      unsigned long long period;
> >      long long quota;
> > +    unsigned long long emulator_period;
> > +    long long emulator_quota;
> >      int ret = -1;
> >      int rc;
> >      bool cpu_bw_status = false;
> > @@ -7992,6 +8095,8 @@ qemuGetSchedulerParametersFlags(virDomainPtr dom,
> >          if (*nparams > 1 && cpu_bw_status) {
> >              period = persistentDef->cputune.period;
> >              quota = persistentDef->cputune.quota;
> > +            emulator_period = persistentDef->cputune.emulator_period;
> > +            emulator_quota = persistentDef->cputune.emulator_quota;
> >          }
> >          goto out;
> >      }
> > @@ -8020,6 +8125,14 @@ qemuGetSchedulerParametersFlags(virDomainPtr dom,
> >          if (rc != 0)
> >              goto cleanup;
> >      }
> > +
> > +    if (*nparams > 3 && cpu_bw_status) {
> > +        rc = qemuGetEmulatorBandwidthLive(vm, group, &emulator_period,
> > +                                          &emulator_quota);
> > +        if (rc != 0)
> > +            goto cleanup;
> > +    }
> > +
> >  out:
> >      if (virTypedParameterAssign(&params[0], VIR_DOMAIN_SCHEDULER_CPU_SHARES,
> >                                  VIR_TYPED_PARAM_ULLONG, shares) < 0)
> > @@ -8042,6 +8155,24 @@ out:
> >                  goto cleanup;
> >              saved_nparams++;
> >          }
> > +
> > +        if (*nparams > saved_nparams) {
> > +            if (virTypedParameterAssign(&params[3],
> > +                                        VIR_DOMAIN_SCHEDULER_EMULATOR_PERIOD,
> > +                                        VIR_TYPED_PARAM_ULLONG,
> > +                                        emulator_period) < 0)
> > +                goto cleanup;
> > +            saved_nparams++;
> > +        }
> > +
> > +        if (*nparams > saved_nparams) {
> > +            if (virTypedParameterAssign(&params[4],
> > +                                        VIR_DOMAIN_SCHEDULER_EMULATOR_QUOTA,
> > +                                        VIR_TYPED_PARAM_LLONG,
> > +                                        emulator_quota) < 0)
> > +                goto cleanup;
> > +            saved_nparams++;
> > +        }
> >      }
> >  
> >      *nparams = saved_nparams;
> 
>   Okay, we now have 5 parameters instead of 3. that looks fine, ACK,
> 
>   the question I have is if virsh is actually able to display the 5
> parameters by default now, if yes the patch set seems complete !

Indeed. The virsh output here is:

virsh schedinfo example-domain
Scheduler      : posix
cpu_shares     : 1024
vcpu_period    : 100000
vcpu_quota     : -1
emulator_period: 400000
emulator_quota : 100000

-- 
Thanks,
Hu Tao