Commit c27cea4416 ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")
broke map_kptr selftest since it removed the function we were kprobing.
Use a new kfunc that invokes call_rcu_tasks_trace and sets a program
provided pointer to an integer to 1. Technically this can be unsafe if
the memory being written to from the callback disappears, but this is
just for usage in a test where we ensure we spin until we see the value
to be set to 1, so it's ok.
Reported-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
Fixes: c27cea4416 ("rcu: Re-implement RCU Tasks Trace in terms of SRCU-fast")
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20260211185747.3630539-1-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Firstly, ensure programs successfully load when using all of the
supported maps. Then, extend existing tests to test more cases at
runtime. We are currently testing both the synchronous freeing of items
and asynchronous destruction when map is freed, but the code needs to be
adjusted a bit to be able to also accomodate support for percpu maps.
We now do a delete on the item (and update for array maps which has a
similar effect for kptrs) to perform a synchronous free of the kptr, and
test destruction both for the synchronous and asynchronous deletion.
Next time the program runs, it should observe the refcount as 1 since
all existing references should have been released by then. By running
the program after both possible paths freeing kptrs, we establish that
they correctly release resources. Next, we augment the existing test to
also test the same code path shared by all local storage maps using a
task local storage map.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Link: https://lore.kernel.org/r/20230225154010.391965-4-memxor@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
