Subject: Re: [PATCH v6 2/2] tr2: log parent process name

From: Ævar Arnfjörð Bjarmason <[email-masked]>
Date: Mon, 02 Aug 2021 14:45:58 +0200

On Mon, Aug 02 2021, Ævar Arnfjörð Bjarmason wrote:

> On Wed, Jul 21 2021, Emily Shaffer wrote:
>
>> +`"cmd_ancestry"`::
>> +	This event contains the text command name for the parent (and earlier
>> +	generations of parents) of the current process, in an array ordered from
>> +	nearest parent to furthest great-grandparent. It may not be implemented
>> +	on all platforms.
>> ++
>> +------------
>> +{
>> +	"event":"cmd_ancestry",
>> +	...
>> +	"ancestry":["bash","tmux: server","systemd"]
>> +}
>> +------------
>> +
>
> Okey, so because of later NEEDSWORK no system that runs systemd will
> currrently have output like this, just Windows.
>
>> +	/*
>> +	 * NEEDSWORK: We could gather the entire pstree into an array to match
>> +	 * functionality with compat/win32/trace2_win32_process_info.c.
>> +	 * To do so, we may want to examine /proc/<pid>/stat. For now, just
>> +	 * gather the immediate parent name which is readily accessible from
>> +	 * /proc/$(getppid())/comm.
>> +	 */
>
> This comment:

To clarify, this was ment to be continued with "seems to remove the
need..." below. But I later inserted the commentery about switch/case
in-between, which made that unclear.

> [...]
>> [...]
>> +		/*
>> +		 * NEEDSWORK: we could do the entire ptree in an array instead,
>> +		 * see compat/win32/trace2_win32_process_info.c.
>> +		 */
>
> Seems to remove the need for this comment, i.e. we comment on this
> limitation of linux-specific get_ancestry_names twice, both in the
> function and its caller.