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Re: patches to actually use markers?
Hi -
On Fri, Nov 16, 2007 at 03:10:15PM -0500, Mathieu Desnoyers wrote:
> [...]
> > How would this syscall specific function get ebx or the string,
> > without ebx (or regs) being passed as marker arguments?
> That's the idea : in the syscall specific function (not in
> syscall_trace()), we add another marker that takes the syscall
> specific arguments as parameter. I think we use the same approach
> there.
I see. Yes, per-systemcall markers would be welcome by our group, and
ones not dependent on TIF_TRACE or whatnot even more so. But were
trying not to get too optimistic.
> What I was saying is that we can't extract the string from
> syscall_trace() because we have no idea it is a string.
If "we" is a marker callback function that is given the system call
number, it can be taught. This is the sort of thing we do currently
in systemtap script code based upon kprobes.
- FChE