On Thu, 21 Mar 2019 20:31:52 +0100
Peter Zijlstra <[email protected]> wrote:
> >
> > No I didn't. Some users only care about performance, but find memory
> > cheap.
>
> Because cache-misses are free?
If I ever did implement this, I would try to get all the data out of
line as much as possible, where only a nop would be inserted:
jmp lockdep_code
raw_locking
1:
[..]
lockdep_code:
do all that lockdep needs
raw_locking
jmp 1b
and have that converted to:
nop // jmp lockdep_code
raw_locking
1:
when disabled. So the only extra pressure on the icache is the nop.
-- Steve