24x7 counters can belong to different domains (core, chip, virtual CPU
etc). For events in the 'chip' domain, sysfs entry currently looks like:
$ cd /sys/bus/event_source/devices/hv_24x7/events
$ cat PM_XLINK_CYCLES__PHYS_CHIP
domain=0x1,offset=0x230,core=?,lpar=0x0
where the required parameter, 'core=?' is specified with perf as:
perf stat -C 0 -e hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,core=1/ \
/bin/true
This is inconsistent in that 'core' is a required parameter for a chip
event. Instead, have the the sysfs entry display 'chip=?' for chip
events:
$ cd /sys/bus/event_source/devices/hv_24x7/events
$ cat PM_XLINK_CYCLES__PHYS_CHIP
domain=0x1,offset=0x230,chip=?,lpar=0x0
We also need to add a 'chip' entry in the sysfs format directory:
$ ls /sys/bus/event_source/devices/hv_24x7/format
chip core domain lpar offset vcpu
^^^^
(new)
so the perf tool can automatically check usage and format the chip
parameter correctly:
$ perf stat -C 0 -v -e hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP/ \
/bin/true
Required parameter 'chip' not specified
invalid or unsupported event: 'hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP/'
$ perf stat -C 0 -v -e hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,chip=1/ \
/bin/true
hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,chip=1/: 0 6628908 6628908
Performance counter stats for 'CPU(s) 0':
0 hv_24x7/PM_XLINK_CYCLES__PHYS_CHIP,chip=1/
0.006606970 seconds time elapsed
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
e5a5886d7a