[PATCH] Linux Kernel Markers 0.11 for 2.6.17
Frank Ch. Eigler
fche@redhat.com
Mon Sep 25 16:01:00 GMT 2006
Hi -
> [...]
> - It _does not_ change the compiler optimisations.
Like any similar mechanism, it does force the compiler to change its
code generation, so one can't claim this too strongly.
> [...] Comments are welcome,
I'm still uneasy about the use of varargs. The current code now uses
the formatting string as metadata to be matched (strcmp) between
producer and consumer. A general tool that would use them would have
to start parsing general printf directives. I believe they are not
quite general enough either e.g. to describe a raw binary blob.
I realize they serve a useful purpose in abbreviating what otherwise
one might have to do (like that multiplicity of STAP_MARK_* type/arity
permutations). But maybe there is a better way.
Also, while regparm(0) may provide some comfort on x86, is there good
reason to believe that the same trick works (and will continue to
work) on non-x86 platforms to invoke a non-varargs callee with a
varargs caller?
- FChE
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: not available
URL: <http://sourceware.org/pipermail/systemtap/attachments/20060925/8619aa5f/attachment.sig>
More information about the Systemtap
mailing list