Hi Jiri,
On 3/16/2021 1:37 AM, Jiri Olsa wrote:
On Mon, Mar 15, 2021 at 10:28:12AM +0800, Jin, Yao wrote:
Hi Jiri,
On 3/13/2021 3:15 AM, Jiri Olsa wrote:
On Thu, Mar 11, 2021 at 03:07:26PM +0800, Jin Yao wrote:
On hybrid platform, some hardware events are only available
on a specific pmu. For example, 'L1-dcache-load-misses' is only
available on 'cpu_core' pmu. And even for the event which can be
available on both pmus, the user also may want to just enable
one event. So now following syntax is supported:
cpu_core/<hardware event>/
cpu_core/<hardware cache event>/
cpu_core/<pmu event>/
cpu_atom/<hardware event>/
cpu_atom/<hardware cache event>/
cpu_atom/<pmu event>/
It limits the event to be enabled only on a specified pmu.
The patch uses this idea, for example, if we use "cpu_core/LLC-loads/",
in parse_events_add_pmu(), term->config is "LLC-loads".
hum, I don't understand how this doest not work even now,
I assume both cpu_core and cpu_atom have sysfs device directory
with events/ directory right?
Yes, we have cpu_core and cpu_atom directories with events.
root@ssp-pwrt-002:/sys/devices/cpu_atom/events# ls
branch-instructions bus-cycles cache-references instructions
mem-stores topdown-bad-spec topdown-fe-bound
branch-misses cache-misses cpu-cycles mem-loads
ref-cycles topdown-be-bound topdown-retiring
root@ssp-pwrt-002:/sys/devices/cpu_core/events# ls
branch-instructions cache-misses instructions mem-stores
topdown-bad-spec topdown-fe-bound topdown-mem-bound
branch-misses cache-references mem-loads ref-cycles
topdown-be-bound topdown-fetch-lat topdown-retiring
bus-cycles cpu-cycles mem-loads-aux slots
topdown-br-mispredict topdown-heavy-ops
and whatever is defined in events we allow in parsing syntax..
why can't we treat them like 2 separated pmus?
But if without this patch, it reports the error,
root@ssp-pwrt-002:~# ./perf stat -e cpu_core/cycles/ -a -vv -- sleep 1
event syntax error: 'cpu_core/cycles/'
\___ unknown term 'cycles' for pmu 'cpu_core'
yep, because there's special care for 'cycles' unfortunately,
but you should be able to run 'cpu_core/cpu-cycles/' right?
Yes, cpu_core/cpu-cycles/ is OK.
# ./perf stat -e cpu_core/cpu-cycles/ -a -- sleep 1
Performance counter stats for 'system wide':
12,831,980,326 cpu_core/cpu-cycles/
1.003132639 seconds time elapsed
valid terms:
event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,name,period,percore
Initial error:
event syntax error: 'cpu_core/cycles/'
\___ unknown term 'cycles' for pmu 'cpu_core'
valid terms:
event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,name,period,percore
Run 'perf list' for a list of valid events
The 'cycles' is treated as a unknown term, then it errors out.
yep, because it's not in events.. we could add special rule to
treat cycles as cpu-cycles inside pmu definition ;-)
jirka
But not only the cycles, the branches has error too.
# ./perf stat -e cpu_core/branches/ -a -- sleep 1
event syntax error: 'cpu_core/branches/'
\___ unknown term 'branches' for pmu 'cpu_core'
valid terms:
event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,name,period,percore
Initial error:
event syntax error: 'cpu_core/branches/'
\___ unknown term 'branches' for pmu 'cpu_core'
Of course, branch-instructions runs OK.
# ./perf stat -e cpu_core/branch-instructions/ -a -- sleep 1
Performance counter stats for 'system wide':
136,655,302 cpu_core/branch-instructions/
1.003171561 seconds time elapsed
So we need special rules for both cycles and branches.
The worse thing is, we also need to process the hardware cache events.
# ./perf stat -e cpu_core/LLC-loads/
event syntax error: 'cpu_core/LLC-loads/'
\___ unknown term 'LLC-loads' for pmu 'cpu_core'
valid terms:
event,pc,edge,offcore_rsp,ldlat,inv,umask,frontend,cmask,config,config1,config2,name,period,percore
Initial error:
event syntax error: 'cpu_core/LLC-loads/'
\___ unknown term 'LLC-loads' for pmu 'cpu_core'
If we use special rules for establishing all event mapping, that looks too
much. :(
Thanks
Jin Yao