Re: [PATCH] perf vendor events arm64: Add hip08 implementation defined PMU core events

[John Garry <john.garry@huawei.com>]

On 18/10/2017 11:49, Will Deacon wrote:
> On Wed, Oct 18, 2017 at 10:25:39AM +0100, John Garry wrote:
>> On 17/10/2017 13:59, Will Deacon wrote:
>>> Hi Shaokun,
>>>
>>> Thanks for the patch. One comment below.
>>>
>>> On Tue, Oct 17, 2017 at 03:01:39PM +0800, Shaokun Zhang wrote:
>>>> This is a short list of useful implementation defined PMU events of
>>>> hip08, other supported events are not listed in this JSON file.
>>>>
>>>> This patch is dependent on Cavium's patch-v9 (Add support for
>>>> ThunderX2 pmu events using json files), Link:
>>>> https://www.spinics.net/lists/arm-kernel/msg611895.html
>>>>
>>>> Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
>>>> Cc: Peter Zijlstra <peterz@infradead.org>
>>>> Cc: Ingo Molnar <mingo@redhat.com>
>>>> Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
>>>> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
>>>> Cc: Will Deacon <will.deacon@arm.com>
>>>> Cc: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
>>>> Cc: John Garry <john.garry@huawei.com>
>>>> ---
>>>> .../arch/arm64/hisilicon/hip08-imp-def.json        | 176 +++++++++++++++++++++
>>>> tools/perf/pmu-events/arch/arm64/mapfile.csv       |   1 +
>>>> 2 files changed, 177 insertions(+)
>>>> create mode 100644 tools/perf/pmu-events/arch/arm64/hisilicon/hip08-imp-def.json
>>>>
>>>> diff --git a/tools/perf/pmu-events/arch/arm64/hisilicon/hip08-imp-def.json b/tools/perf/pmu-events/arch/arm64/hisilicon/hip08-imp-def.json
>>>> new file mode 100644
>>>> index 0000000..6bb31da
>>>> --- /dev/null
>>>> +++ b/tools/perf/pmu-events/arch/arm64/hisilicon/hip08-imp-def.json
>>>> @@ -0,0 +1,176 @@
>>>> +[
>>>> +    {
>>>> +        "PublicDescription": "Attributable Level 1 data cache access, read",
>>>> +        "EventCode": "0x40",
>>>> +        "EventName": "L1D_CACHE_RD",
>>>> +        "BriefDescription": "L1D cache access, read",
>>>> +    },
>>>> +    {
>>>> +        "PublicDescription": "Attributable Level 1 data cache access, write",
>>>> +        "EventCode": "0x41",
>>>> +        "EventName": "L1D_CACHE_WR",
>>>> +        "BriefDescription": "L1D cache access, write",
>>>> +    },
>>>
>>> So these are the same as the events in cavium/thunderx2-imp-def.json and
>>> should be factored out. In fact, ARM recommends event numbers for 0x40-0xBF,
>>> so the best thing would be to have those defined in their own file, then
>>> have a way for the various CPU-specific .json files to pick and chose the
>>> events they need from there.
>>
>> Right, this seems reasonable. Just need to check on feasible.
>>
>> In terms of coordinating this work, shall we do it? Will arm64+ThunderX
>> support be accepted as is?
>
> Yes, that would be my preference if you don't mind.


Cool.

I am looking at this topic now. But I am doubting the folder structure 
again.

Firstly, we still have this comment in the README:
All the topic JSON files for a CPU model/family should be in a separate
sub directory.

Now, when thunderx3 or hip09 comes along, I assume that their jsons will 
similarly go into cavium and hisilcon folders, respectively. So, for 
example, we add thunderx3 json, like this:
arm64/cavium/thunderx3-imp-def.json
[
     {
         "PublicDescription": "foo",
         "EventCode": "0x40",
         "EventName": "bar",
         "BriefDescription": "sieve",
     },
]

#Family-model,Version,Filename,EventType
0x00000000420f5160,v1,cavium,core
0x00000000420f5161,v1,cavium,core

Then we have generated pmu_events.c, like this:
#include "../../pmu-events/pmu-events.h"
struct pmu_event pme_cavium[] = {
{
     .name = "bar",
     .event = "event=0x40",
     .desc = "sieve",
     .topic = "thunderx3 imp def",
     .long_desc = "foo",
},
{
     .name = "l1d_cache_rd",
     .event = "event=0x40",
     .desc = "L1D cache read",
     .topic = "thunderx2 imp def",
     .long_desc = "Attributable Level 1 data cache access, read",
},
{
     .name = "l1d_cache_wr",
     .event = "event=0x41",
     .desc = "L1D cache write",
     .topic = "thunderx2 imp def",
     .long_desc = "Attributable Level 1 data cache access, write ",
},

[ ... ]

{
     .name = 0,
     .event = 0,
     .desc = 0,
},
};
struct pmu_events_map pmu_events_map[] = {
{
     .cpuid = "0x00000000420f5160",
     .version = "v1",
     .type = "core",
     .table = pme_cavium
},
{
     .cpuid = "0x00000000420f5161",
     .version = "v1",
     .type = "core",
     .table = pme_cavium
},
{
     .cpuid = 0,
     .version = 0,
     .type = 0,
     .table = 0,
},
};

It doesn't look right, espcially since we have conflicting definitions 
for event 0x40. We really should have table per cpu.

John


>
> Will
>
> .
>