lkml.org 
[lkml]   [2022]   [Sep]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
SubjectRe: [PATCH] perf script: Skip dummy event attr check
From


On 9/7/2022 12:50 PM, Namhyung Kim wrote:
> Hello,
>
> On Tue, Sep 6, 2022 at 7:49 PM Xing Zhengjun
> <zhengjun.xing@linux.intel.com> wrote:
>>
>> Hi,
>>
>> On 9/1/2022 12:23 AM, Arnaldo Carvalho de Melo wrote:
>>> Em Wed, Aug 31, 2022 at 09:02:46AM -0700, Ian Rogers escreveu:
>>>> On Wed, Aug 31, 2022 at 5:40 AM Jiri Olsa <jolsa@kernel.org> wrote:
>>>>>
>>>>> Hongtao Yu reported problem when displaying uregs in perf script
>>>>> for system wide perf.data:
>>>>>
>>>>> # perf script -F uregs | head -10
>>>>> Samples for 'dummy:HG' event do not have UREGS attribute set. Cannot print 'uregs' field.
>>>>>
>>>>> The problem is the extra dummy event added for system wide,
>>>>> which does not have proper sample_type setup.
>>>>>
>>>>> Skipping attr check completely for dummy event as suggested
>>>>> by Namhyung, because it does not have any samples anyway.
>>>>>
>>>>> Reported-by: Hongtao Yu <hoy@fb.com>
>>>>> Suggested-by: Namhyung Kim <namhyung@kernel.org>
>>>>> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
>>>>
>>>> Acked-by: Ian Rogers <irogers@google.com>
>>>
>>> Thanks, applied to perf/urgent.
>>>
>>> - Arnaldo
>>
>> I have met a similar issue on hybrid systems such as ADL, I apply the
>> patch, and it works OK for the normal mode.
>> # ./perf record --intr-regs=di,r8,dx,cx -e
>> br_inst_retired.near_call:p -c 1000 --per-thread true
>> [ perf record: Woken up 1 times to write data ]
>> [ perf record: Captured and wrote 0.024 MB perf.data (25 samples) ]
>>
>> # ./perf script -F iregs |head -5
>> ABI:2 CX:0xffff90e19d024ed8 DX:0x1 DI:0xffff90e19d024ed8
>> R8:0xffffba5e437e7b30
>> ABI:2 CX:0x7f5239783000 DX:0x80000000 DI:0xffff90e1801eea00
>> R8:0x71
>> ABI:2 CX:0x40 DX:0x60 DI:0xffffffff9fde5ab8 R8:0x40
>> ABI:2 CX:0x0 DX:0xffffffffffffffff DI:0xffff90e1877408e8
>> R8:0x1
>> ABI:2 CX:0xcc0 DX:0x1 DI:0xffff90e187d17c60 R8:0x40
>>
>> But the issue still happened when running the test in the pipe mode. In
>> the pipe mode, it calls process_attr() which still checks the attr for
>> the dummy event, so the issue happened.
>>
>> # ./perf record -o - --intr-regs=di,r8,dx,cx -e
>> br_inst_retired.near_call:p -c 1000 --per-thread true 2>/dev/null|./perf
>> script -F iregs |head -5
>> Samples for 'dummy:HG' event do not have IREGS attribute set. Cannot
>> print 'iregs' field.
>> 0x120 [0x90]: failed to process type: 64
>>
>> I have one test patch which can fix the pipe mode issue.
>>
>> ./perf record -o - --intr-regs=di,r8,dx,cx -e
>> br_inst_retired.near_call:p -c 1000 --per-thread true 2>/dev/null|./perf
>> script -F iregs |head -5
>> ABI:2 CX:0xffff90e18119e278 DX:0x0 DI:0xffff90e18119f858
>> R8:0xffff90e18119e278
>> ABI:2 CX:0x0 DX:0x1 DI:0xfffffa2844a91580 R8:0x402
>> ABI:2 CX:0x0 DX:0x0 DI:0x100cca R8:0x0
>> ABI:2 CX:0x0 DX:0x0 DI:0xffffffff9e997ca5 R8:0x0
>> ABI:2 CX:0x113ce8000 DX:0xffff90e198f46600
>> DI:0xffff90e189de8000 R8:0x290
>>
>>
>> Fixes: b91e5492f9d7 ("perf record: Add a dummy event on hybrid systems
>> to collect metadata records")
>> Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
>> ---
>> tools/perf/builtin-script.c | 2 ++
>> 1 file changed, 2 insertions(+)
>>
>> diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
>> index 9152e3e45b69..2d863cdb19fe 100644
>> --- a/tools/perf/builtin-script.c
>> +++ b/tools/perf/builtin-script.c
>> @@ -2429,6 +2429,8 @@ static int process_attr(struct perf_tool *tool,
>> union perf_event *event,
>> }
>>
>> if (evsel->core.attr.sample_type) {
>> + if (evsel__is_dummy_event(evsel))
>> + return 0;
>
> Maybe we can move this into evsel__check_attr().
>
> Thanks,
> Namhyung

Yes, the following changes in evsel__check_attr() can fix both normal
and pipe mode issues, Otherwise, we have to patch everywhere when
evsel__check_attr() is called.

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 13580a9c50b8..fb76e3191858 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -451,6 +451,9 @@ static int evsel__check_attr(struct evsel *evsel,
struct perf_session *session)
allow_user_set = perf_header__has_feat(&session->header,
HEADER_AUXTRACE);

+ if (evsel__is_dummy_event(evsel))
+ allow_user_set = true;
+
if (PRINT_FIELD(TRACE) &&
!perf_session__has_traces(session, "record -R"))
return -EINVAL;
--
2.25.1
>
>
>> err = evsel__check_attr(evsel, scr->session);
>> if (err)
>> return err;
>> --
>> 2.25.1
>>
>> --
>> Zhengjun Xing

--
Zhengjun Xing

\
 
 \ /
  Last update: 2022-09-07 07:20    [W:1.873 / U:0.016 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site