Re: [PATCH] selftests/ftrace: remove _do_fork() leftovers

[Steven Rostedt]

On Fri, 23 Oct 2020 11:49:48 -0400
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Fri, 23 Oct 2020 17:12:44 +0200
> Alexander Gordeev <agordeev@xxxxxxxxxxxxx> wrote:
> 
> > > Perhaps we should have:
> > > 
> > > 	# older kernels have do_fork, but newer kernels have kernel_clone
> > > 	echo kernel_clone >> set_ftrace_filter || echo *do_fork >> set_ftrace_filter    
> > 
> > Would you suggest to do the same with all occurences in
> > eea11285dab3 ("tracing: switch to kernel_clone()")?
> > Otherwise it does not really make sense to just fix couple
> > of tests out of dozens.  
> 
> Yes. I haven't pulled in the updated tests, so I haven't hit the errors yet
> (nor have I merged my work with the switch to the new name yet). So those
> will most definitely break my tests.
> 
> But because it's a more generic issue, we should have a way to find what to
> use. Perhaps add to the test.d/functions, something like:
> 
> FUNCTION_FORK=`(if grep '\bkernel_clone\b' /proc/kallsyms > /dev/null; then
>                 echo kernel_clone; else echo '_do_fork'; fi)`
> 
> and use $FUNCTION_FORK everywhere that references it.
> 
> 

Let me pull in the latest changes, and whip up a patch that works on both
the older kernels as well as the newer ones.

-- Steve