Re: Lookup of cookie failed

[Dave D. <dde...@es...>]

"Eric Fisher" <joe...@gm...> writes:

> hi all,
> 
> What does this mean? Oprofile can't get samples of the programs. Is it
> a problem of the kernel or of the oprofile? The log is,
> 
> oprofiled started Thu Oct 16 11:24:05 2008
> kernel pointer size: 8
> Lookup of cookie 98000000018d3050 failed, errno=22
> Lookup of cookie 98000000018d1110 failed, errno=22

etc

You don't say what target this was, but "kernel pointer size: 8" is
interesting.  I saw something very similar when trying to get oprofile working on an old
sgi Indy box.  That's actually a mips-64 cpu, but I was running a (debian)32-bit kernel.
So there turned out to be a mismatch somewhere in the system call interface,
or something.  Anyway, problem was that the cookie values somehow
got lost in translation between user-mode and kernel-mode.

I'm sorry to say that I don't have detailed notes - all I seem to have is
"had to tweak oprofiled a bit to get the system call to work - the kernel is 64-bit I think."

The sources are probably still on the machine, but it's turned off at the
moment (and I'm at home so can't turn it on to investigate)

Ket me know if this sounds relevant and I'll look further next week.

dd
-- 
Dave Denholm              <dde...@es...>       http://www.esmertec.com