[RFC][PATCH 2/2] uprobes: single-step out of line

[Ernie Petrides]

On Friday, 20-Apr-2007 at 15:09 PDT, Jim Keniston wrote:

> This patch enhances uprobes to use "single-stepping out of line"
> (SSOL) to avoid probe misses in multithreaded applications.  SSOL also
> reduces probe overhead by 25-30%.


Hi, Jim.  I just had one question about this (mainly because I'm not
able to work through all the nitty gritty details of the patch).

Is there a way to avoid adding the "uprobe_ssol_area" struct into the
"mm_struct"?  If so, the uprobes module could be easily back-ported to
kABI-frozen distros of the Linux kernel.  If the "mm_struct" ends up
getting changed, that changes the "task_struct" layout, thus breaking
binary compatibility with 3rd-party kernel modules.  (We're not allowed
to do this in RHEL distros.)

Cheers.  -ernie