Re: perf report warnings on tracepoint events hidden by ui

[Namhyung Kim]

Hi,

On Fri, Apr 28, 2017 at 9:31 AM, David Carrillo-Cisneros
<davidcc@xxxxxxxxxx> wrote:
> When processing tracepoint events, perf report outputs warnings about
> field not founds. The warnings are usually hidden by perf report UI
> and appear when using the --stdio option. e.g.

Yep, currently perf report TUI hides warnings since there's no space
to show them.

>
>   $ perf record -e syscalls:sys_enter_mmap some_load
>
>   $ perf report --stdio
>
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field addr not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field len not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field prot not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field flags not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field fd not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field off not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field addr not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field len not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field prot not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field flags not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field fd not found
>   Warning: [syscalls:sys_enter_mmap] eval_num_arg: field off not found
>
> I bisected the warnings to:
>   commit d49dadea78624 ("perf tools: Make 'trace' or 'trace_fields'
> sort key default for tracepoint events").
>
> that introduced sorting by trace. The event's format in my example is:
>
>   $ cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_socket/format
>
>   name: sys_enter_socket
>   ID: 1850
>   format:
>           field:unsigned short common_type;       offset:0;
> size:2; signed:0;
>           field:unsigned char common_flags;       offset:2;
> size:1; signed:0;
>           field:unsigned char common_preempt_count;       offset:3;
>    size:1; signed:0;
>           field:int common_pid;   offset:4;       size:4; signed:1;
>
>   print fmt: "family: 0x%08lx, type: 0x%08lx, protocol: 0x%08lx",
> ((unsigned long)(REC->family)), ((unsigned long)(REC->type)),
> ((unsigned long)(REC->protocol))
>
>
> An appears to be correctly parsed by event_read_print in
> tools/lib/tracevent/event-parse.c . Has anyone seen this before?

But I don't see any warning when I run it with --stdio.  Could you
show me the format file of sys_enter_mmap?


Thanks,
Namhyung