Re: [libvirt] [PATCH 6/8] perf: reenable perf events when libvirtd restart

-----Original Message----- From: Daniel P. Berrange [mailto:berrange@redhat.com] Sent: Thursday, January 28, 2016 11:21 PM To: Ren, Qiaowei Cc: libvir-list(a)redhat.com; Jiri Denemark Subject: Re: [PATCH 6/8] perf: reenable perf events when libvirtd restart On Thu, Dec 10, 2015 at 08:34:36PM +0800, Qiaowei Ren wrote: > When libvirtd daemon restart, this patch will reenable those perf > events previously enabled. > > Signed-off-by: Qiaowei Ren <qiaowei.ren(a)intel.com&gt; > --- > src/qemu/qemu_driver.c | 36 ++++++++++++++++++++++++++++++++++++ > 1 file changed, 36 insertions(+) > > diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index > 7d95364..09607ca 100644 > --- a/src/qemu/qemu_driver.c > +++ b/src/qemu/qemu_driver.c > @@ -164,6 +164,9 @@ static int qemuDomainGetMaxVcpus(virDomainPtr > dom); static int qemuDomainManagedSaveLoad(virDomainObjPtr vm, > void *opaque); > > +static int qemuDomainPerfRestart(virDomainObjPtr vm, > + void *data); > + > static int qemuOpenFile(virQEMUDriverPtr driver, > virDomainObjPtr vm, > const char *path, int oflags, @@ -939,6 > +942,10 @@ qemuStateInitialize(bool privileged, > qemuDomainManagedSaveLoad, > qemu_driver); > > + virDomainObjListForEach(qemu_driver->domains, > + qemuDomainPerfRestart, > + NULL); > + > qemuProcessReconnectAll(conn, qemu_driver); > > qemu_driver->workerPool = virThreadPoolNew(0, 1, 0, > qemuProcessEventHandler, qemu_driver); @@ -3460,6 +3467,35 @@ qemuDomainManagedSaveLoad(virDomainObjPtr vm, > return ret; > } > > +static int > +qemuDomainPerfRestart(virDomainObjPtr vm, > + void *data ATTRIBUTE_UNUSED) { > + size_t i; > + virDomainDefPtr def = vm->def; > + qemuDomainObjPrivatePtr priv = vm->privateData; > + > + virPerfFree(priv->perf); > + > + priv->perf = virPerfNew(); > + if (!priv->perf) > + return -1; > + > + for (i = 0; i < VIR_PERF_EVENT_LAST; i++) { > + if (def->perf->events[i] && > + def->perf->events[i] == VIR_TRISTATE_BOOL_YES) { > + if (virPerfEventEnable(priv->perf, i, vm->pid)) > + goto cleanup; > + } > + } > + > + return 0; > + > + cleanup: > + virPerfFree(priv->perf); > + return -1; > +} > + Oh, I suggested we add this in qemuProcessReconnect in a previous patch