Re: [libvirt] [PATCH 8/9] util: Extend virresctl API to retrieve multiple monitor statistics

On 2019年05月27日 23:26, Michal Privoznik wrote: > On 5/23/19 11:34 AM, Wang Huaqiang wrote: >> Export virResctrlMonitorGetStats and make >> virResctrlMonitorGetCacheOccupancy obsoleted. >> >> Signed-off-by: Wang Huaqiang <huaqiang.wang(a)intel.com&gt; >> --- >>   src/libvirt_private.syms |  1 + >>   src/qemu/qemu_driver.c   | 33 +++++++++++++++++++++++++-------- >>   src/util/virresctrl.c    | 46 >> +++++++++++++++++++++++++++------------------- >>   src/util/virresctrl.h    |  6 ++++++ >>   4 files changed, 59 insertions(+), 27 deletions(-) >> >> diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms >> index 9099757..2e3d48c 100644 >> --- a/src/libvirt_private.syms >> +++ b/src/libvirt_private.syms >> @@ -2771,6 +2771,7 @@ virResctrlMonitorDeterminePath; >>   virResctrlMonitorFreeStats; >>   virResctrlMonitorGetCacheOccupancy; >>   virResctrlMonitorGetID; >> +virResctrlMonitorGetStats; >>   virResctrlMonitorNew; >>   virResctrlMonitorRemove; >>   virResctrlMonitorSetAlloc; >> diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c >> index 4ea346c..bc19171 100644 >> --- a/src/qemu/qemu_driver.c >> +++ b/src/qemu/qemu_driver.c >> @@ -19987,6 +19987,7 @@ >> qemuDomainFreeResctrlMonData(virQEMUResctrlMonDataPtr resdata) >>     /** >>    * qemuDomainGetResctrlMonData: >> + * @driver: Pointer to qemu driver >>    * @dom: Pointer for the domain that the resctrl monitors reside in >>    * @resdata: Pointer of virQEMUResctrlMonDataPtr pointer for >> receiving the >>    *            virQEMUResctrlMonDataPtr array. Caller is responsible >> for >> @@ -20005,16 +20006,29 @@ >> qemuDomainFreeResctrlMonData(virQEMUResctrlMonDataPtr resdata) >>    * Returns -1 on failure, or 0 on success. >>    */ >>   static int >> -qemuDomainGetResctrlMonData(virDomainObjPtr dom, >> +qemuDomainGetResctrlMonData(virQEMUDriverPtr driver, >> +                            virDomainObjPtr dom, >>                               virQEMUResctrlMonDataPtr **resdata, >>                               size_t *nresdata, >>                               virResctrlMonitorType tag) >>   { >>       virDomainResctrlDefPtr resctrl = NULL; >>       virQEMUResctrlMonDataPtr res = NULL; >> +    char **features = NULL; >>       size_t i = 0; >>       size_t j = 0; >>   +    if (tag == VIR_RESCTRL_MONITOR_TYPE_CACHE) { >> +        features = driver->caps->host.cache.monitor->features; > > > No, we have virQEMUDriverGetCapabilities() which ensures that > driver->caps object doesn't go away while accessing this. > I can't refer 'driver->caps->host.cache.monitor->features' directly because this function (qemuDomainGetResctrlMonData) will be used for 'memory bandwidth' monitors also. at that time that the piece of code looks like:   +    if (tag == VIR_RESCTRL_MONITOR_TYPE_CACHE) {    +      if (driver->caps->host.cache.monitor) +            features = driver->caps->host.cache.monitor->features;   +    if (tag == VIR_RESCTRL_MONITOR_TYPE_MEMBW) {    +      if(driver->caps->host.membw) +            features = driver->caps->host.membw.monitor->features;