[Devel] [PATCH 2/6] Rename pid_nr function

[Pavel Emelianov]

Serge E. Hallyn wrote:
> Quoting Pavel Emelianov (xemul at openvz.org):
>> sukadev at us.ibm.com wrote:
>>> Pavel Emelianov [xemul at openvz.org] wrote:
>>> | sukadev at us.ibm.com wrote:
>>> | > Subject: [PATCH 2/6] Rename pid_nr function 
>>> | > 
>>> | > From: Sukadev Bhattiprolu <sukadev at us.ibm.com>
>>> | > 
>>> | > Rename pid_nr() function to pid_to_nr() which is more descriptive
>>> | > and will hopefully cause less confusion with new structure/functions
>>> | > being added to support multiple pid namespaces.
>>> | 
>>> | Don't we need at least two convertors:
>>> | pid_to_nr_as_it_seen_by_current()
>>> | and
>>> | pid_to_nr_as_it_seen_by_some_other_task()
>>>
>>> Can you give me an example of where you would use this latter
>>> (pid_to_nr_as_it_seen_by_some_other_task()) interface ?
>> Easy. Consider you're observing /proc/<pid>/status file for a task
>> that lives in two namespaces - init and some created. When making 
>> "cat" on this from init namespace you must get the task's pid as it
>> is seen from init namespace, but when making "cat" from the created
>> namespace you must see the pid as it is seen by this namespace. And 
>> so on and so forth.
> 
> But 'current' in that case is the process reading the file, so you do in
> fact want to use pid_to_nr_as_it_seen_by_current().

Well. I see. There's a misleading in names. Better would be called them
pid_nr_as_it_is_seen_by_the_owning_task_when_he_reads_it() %)
and
pid_nr_as_it_is_seen_by_arbitrary_task()

the first one is pid_vnr() the second is pid_nr_ns().

> -serge
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