On 2026-09-19 13:00, Linus Torvalds wrote:
On Sat, 19 Sept 2026 at 09:35, Bradley Morgan <[email protected]> wrote:
I think hazard pointers are good, what test do YOU suggest we do here?
I want to see a single real-world example of "look, this speeds this
real load up by 10%, and the kernel code was actually cleaned up in
the process because hazard pointers are great".
Not a microbenchmark that tests just the hazard pointers themselves,
but a real kernel feature that has been converted to hazard pointers,
and in the process actually shows improvement.
The ONLY reason for hazard pointers to ever be merged is if they
actually buy us something real.
So I want to see that 'real" thing.
AFAIR, Boqun wanted to use hazard pointers to cleanup/speed up an
hot lockdep reclaim path. Boqun, Paul, how is this effort going ?
I suspect we should wait until that lockdep user of hazptr is ready for
upstreaming and propose both at the same time, because a synchronization
infrastructure without any significant in tree user is not really
relevant, right ?
Thanks,
Mathieu
--
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com
