Re: [v2,05/12] rcutorture: Add tests for SRCU up/down reader primitives

Paul E. McKenney
2025-04-08T20:58:35Z

On Tue, Apr 08, 2025 at 08:18:05PM -0000, Joel Fernandes wrote:
> Hello, Paul,
>
> On Tue, 8 Apr 2025 20:16:08 GMT, "Paul E. McKenney" wrote:
> > This commit adds a new rcutorture.n_up_down kernel boot parameter
> > that specifies the number of outstanding SRCU up/down readers, which
> > begin in kthread context and end in an hrtimer handler. There is a new
> > kthread ("rcu_torture_updown") that scans an per-reader array looking
> > for elements whose readers have ended. This kthread sleeps between one
> > and two milliseconds between consecutive scans.
> >
> > [ paulmck: Apply kernel test robot feedback. ]
> > [ paulmck: Apply Z qiang feedback. ]
> >
> [...]
> > + for (i = 0; i < n_up_down; i++) {
> > + init_rcu_torture_one_read_state(&updownreaders[i].rtorsu_rtors, rand);
> > + hrtimer_init(&updownreaders[i].rtorsu_hrt, CLOCK_MONOTONIC,
> > + HRTIMER_MODE_REL | HRTIMER_MODE_SOFT);
>
> This will now fail to build and needs the following: I will squash it into my
> for-next branch into this patch, but let me know if you prefer to provide an
> update.

Please feel free to squash it in with your "[]" tag like shown above.

As you say, you will be sending them all out soon enough anyway. ;-)

My plan is to rebase on your stack once you finish your first long-form
round of testing.

Thanx, Paul

> Fix build error by converting hrtimer_init to hrtimer_setup, see:
> https://lore.kernel.org/all/174384280127.31282.2714486346304643188.tip-bot2@tip-bot2/
>
> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
> index 4f0a00a8bdee..14a22ef3b56f 100644
> --- a/kernel/rcu/rcutorture.c
> +++ b/kernel/rcu/rcutorture.c
> @@ -2480,9 +2480,8 @@ static int rcu_torture_updown_init(void)
> }
> for (i = 0; i < n_up_down; i++) {
> init_rcu_torture_one_read_state(&updownreaders[i].rtorsu_rtors, rand);
> - hrtimer_init(&updownreaders[i].rtorsu_hrt, CLOCK_MONOTONIC,
> - HRTIMER_MODE_REL | HRTIMER_MODE_SOFT);
> - updownreaders[i].rtorsu_hrt.function = rcu_torture_updown_hrt;
> + hrtimer_setup(&updownreaders[i].rtorsu_hrt,
> rcu_torture_updown_hrt, CLOCK_MONOTONIC,
> + HRTIMER_MODE_REL | HRTIMER_MODE_SOFT);
> torture_random_init(&updownreaders[i].rtorsu_trs);
> init_rcu_torture_one_read_state(&updownreaders[i].rtorsu_rtors,
> &updownreaders[i].rtorsu_trs);
>
> Thanks.