Validity of execname() pid() tid() information

[Frank Ch. Eigler]

Hi -

On Thu, Apr 24, 2008 at 05:09:23PM +0200, Hohl, Adolf wrote:

> I am using the systemtap tool to instrument low level file system
> routines. in NFS. Since some of these calls are made due to cache
> tighness or from queues some time they were triggered by the
> application my question is if execname(), pid() and tid() still
> report the values on behalf of which process they were made.

The functions you list rely on the kernel's "current" variable
(current task running on this CPU) to extract the information.  They
do not look through data like a block device's I/O queue to figure out
which processes may be indirectly connected, nor which process is
likely to consume data coming from e.g. an interrupt handler.  (Such
"blame" routines would be tricky to write but very interesting.)

- FChE