| Message ID | 20200709051836.723765-3-kjain@linux.ibm.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 792f73f747b82f6cb191a323e1f5755d33149b50 |
| Headers | show |
| Series | Add cpu hotplug support for powerpc/perf/hv-24x7 | expand |
On 7/9/20 10:48 AM, Kajol Jain wrote: > Patch here adds a cpumask attr to hv_24x7 pmu along with ABI documentation. > > Primary use to expose the cpumask is for the perf tool which has the > capability to parse the driver sysfs folder and understand the > cpumask file. Having cpumask file will reduce the number of perf command > line parameters (will avoid "-C" option in the perf tool > command line). It can also notify the user which is > the current cpu used to retrieve the counter data. > > command:# cat /sys/devices/hv_24x7/interface/cpumask > 0 Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com> > Signed-off-by: Kajol Jain <kjain@linux.ibm.com> > --- > .../ABI/testing/sysfs-bus-event_source-devices-hv_24x7 | 7 +++++++ > arch/powerpc/perf/hv-24x7.c | 8 ++++++++ > 2 files changed, 15 insertions(+) > > diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 b/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 > index e8698afcd952..f7e32f218f73 100644 > --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 > +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 > @@ -43,6 +43,13 @@ Description: read only > This sysfs interface exposes the number of cores per chip > present in the system. > > +What: /sys/devices/hv_24x7/interface/cpumask > +Date: July 2020 > +Contact: Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org> > +Description: read only > + This sysfs file exposes the cpumask which is designated to make > + HCALLs to retrieve hv-24x7 pmu event counter data. > + > What: /sys/bus/event_source/devices/hv_24x7/event_descs/<event-name> > Date: February 2014 > Contact: Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org> > diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c > index 93b4700dcf8c..acc34148ad09 100644 > --- a/arch/powerpc/perf/hv-24x7.c > +++ b/arch/powerpc/perf/hv-24x7.c > @@ -448,6 +448,12 @@ static ssize_t device_show_string(struct device *dev, > return sprintf(buf, "%s\n", (char *)d->var); > } > > +static ssize_t cpumask_show(struct device *dev, > + struct device_attribute *attr, char *buf) > +{ > + return cpumap_print_to_pagebuf(true, buf, &hv_24x7_cpumask); > +} > + > static ssize_t sockets_show(struct device *dev, > struct device_attribute *attr, char *buf) > { > @@ -1115,6 +1121,7 @@ static DEVICE_ATTR_RO(domains); > static DEVICE_ATTR_RO(sockets); > static DEVICE_ATTR_RO(chipspersocket); > static DEVICE_ATTR_RO(coresperchip); > +static DEVICE_ATTR_RO(cpumask); > > static struct bin_attribute *if_bin_attrs[] = { > &bin_attr_catalog, > @@ -1128,6 +1135,7 @@ static struct attribute *if_attrs[] = { > &dev_attr_sockets.attr, > &dev_attr_chipspersocket.attr, > &dev_attr_coresperchip.attr, > + &dev_attr_cpumask.attr, > NULL, > }; >
diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 b/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 index e8698afcd952..f7e32f218f73 100644 --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-hv_24x7 @@ -43,6 +43,13 @@ Description: read only This sysfs interface exposes the number of cores per chip present in the system. +What: /sys/devices/hv_24x7/interface/cpumask +Date: July 2020 +Contact: Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org> +Description: read only + This sysfs file exposes the cpumask which is designated to make + HCALLs to retrieve hv-24x7 pmu event counter data. + What: /sys/bus/event_source/devices/hv_24x7/event_descs/<event-name> Date: February 2014 Contact: Linux on PowerPC Developer List <linuxppc-dev@lists.ozlabs.org> diff --git a/arch/powerpc/perf/hv-24x7.c b/arch/powerpc/perf/hv-24x7.c index 93b4700dcf8c..acc34148ad09 100644 --- a/arch/powerpc/perf/hv-24x7.c +++ b/arch/powerpc/perf/hv-24x7.c @@ -448,6 +448,12 @@ static ssize_t device_show_string(struct device *dev, return sprintf(buf, "%s\n", (char *)d->var); } +static ssize_t cpumask_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return cpumap_print_to_pagebuf(true, buf, &hv_24x7_cpumask); +} + static ssize_t sockets_show(struct device *dev, struct device_attribute *attr, char *buf) { @@ -1115,6 +1121,7 @@ static DEVICE_ATTR_RO(domains); static DEVICE_ATTR_RO(sockets); static DEVICE_ATTR_RO(chipspersocket); static DEVICE_ATTR_RO(coresperchip); +static DEVICE_ATTR_RO(cpumask); static struct bin_attribute *if_bin_attrs[] = { &bin_attr_catalog, @@ -1128,6 +1135,7 @@ static struct attribute *if_attrs[] = { &dev_attr_sockets.attr, &dev_attr_chipspersocket.attr, &dev_attr_coresperchip.attr, + &dev_attr_cpumask.attr, NULL, };
Patch here adds a cpumask attr to hv_24x7 pmu along with ABI documentation. Primary use to expose the cpumask is for the perf tool which has the capability to parse the driver sysfs folder and understand the cpumask file. Having cpumask file will reduce the number of perf command line parameters (will avoid "-C" option in the perf tool command line). It can also notify the user which is the current cpu used to retrieve the counter data. command:# cat /sys/devices/hv_24x7/interface/cpumask 0 Signed-off-by: Kajol Jain <kjain@linux.ibm.com> --- .../ABI/testing/sysfs-bus-event_source-devices-hv_24x7 | 7 +++++++ arch/powerpc/perf/hv-24x7.c | 8 ++++++++ 2 files changed, 15 insertions(+)