[Toybox] Simplifying (was Re: top -H segfault)

[enh]

On Wed, Jun 8, 2016 at 6:37 PM, Rob Landley <rob at landley.net> wrote:
> On 06/06/2016 05:33 PM, enh wrote:
>> On Mon, Jun 6, 2016 at 12:41 PM, Rob Landley <rob at landley.net> wrote:
>>> Too much chatter, let me simplify. (Patch inlined below.)
>>>> I checked in a thing,
>>>
>>> Let me know if that (in current git) is now displaying what you want.
>>
>> that gives me enough to replace toolbox top.
>
> Is the patch below better behavior than this, or is this good enough?
>
>> an example that should be unwrapped enough to be legible:
>>
>> $ adb shell toybox top -b -n 1 -H -s 6 -o pid,tid,tname,comm | grep adbd
>>   PID   TID TNAME                      [COMM]
>>   190   192 adbd                        usb ffs open
>>   190  2585 adbd                        shell srvc 40
>>   190   190 adbd                        adbd
>>   190   194 adbd                        <-transport
>>   190   193 adbd                        ->transport
>>
>> as you can see, TNAME is the process name and COMM is the thread name.
>> (this is true of how any Linux libc implements thread names.)
>
> TNAME is argv[0] of $PID, COMM is stat[2]
>
> I'm guessing you _do_ want the below patch...? Maybe?
>
>> but, yeah, since "NAME" is a non-standard extension added for Android
>> compatibility anyway, NAME makes sense too :-)
>
> And rename to NAME. Ok...?

yeah, i definitely think TNAME should replace NAME.

>>>>>  1939  1939 root     20   0  0.0 S      0     0  fg
>>>>>          kworker/0:3
>>>>
>>>> You're showing me what it _is_ doing, not what you want. Let me try to
>>>> guess what you want.
>>>>
>>>> In this case pid==tid, so... you want TNAME to show argv[0] of the
>>>> current process in that case? Maybe?
>>>>
>>>> Something like the attached patch, maybe?
>>>
>>> Here is the patch making a second guess at what you want. It's on
>>> top of current git (the above "is this what you want"), and changes
>>> the TNAME behavior to "Show parent argv[0]. If that's blank, show
>>> our argv[0]. If that's blank, show [stat2]."
>>>
>>> That way threads show their parents, parents show themselves, and
>>> kernel threads show the [stat2] name. Is this what you want?
>>
>> yeah, as far as i can tell this is right.
>
> Ok, I'll apply it then.

i can't actually tell any difference from this patch. remind me what changed?

> Rob



-- 
Elliott Hughes - http://who/enh - http://jessies.org/~enh/
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