On Tue, Mar 12, 2024 at 03:23:57PM +0800, Zqiang wrote:
> This commit make rcu-tasks related rcutorture test support rcu-tasks
> gp state printing when the writer stall occurs or the at the end of
> rcutorture test.
>
> The test is as follows:
> [ 3872.548702] tasks-tracing: Start-test grace-period state: g4560 f0x0
> [ 4332.661283] tasks-tracing: End-test grace-period state: g41540 f0x0
> total-gps=36980
>
> [ 4401.381138] tasks: Start-test grace-period state: g8 f0x0
> [ 4565.619354] tasks: End-test grace-period state: g1732 f0x0 total-gps=1724
>
> [ 4589.006917] tasks-rude: Start-test grace-period state: g8 f0x0
> [ 5059.379321] tasks-rude: End-test grace-period state: g8508 f0x0
> total-gps=8500
>
> Signed-off-by: Zqiang <[email protected]>
Again, good eyes, and that fix would work. But wouldn't it make more
sense to create a new cur_ops function pointer for these functions?
That might allow getting rid of the *_FLAVOR checks and values, plus
simplify the code a bit. To make the function signatures work out,
there would need to be an intermediate SRCU function to supply the right
rcu_struct pointer.
This would shorten and simplify the code a bit.
Or is there some reason that this won't work?
Why didn't I do that to start with? Well, the various RCU flavors
appeared one at a time over some years... ;-)
Thanx, Paul
> ---
> kernel/rcu/rcu.h | 8 ++++++++
> kernel/rcu/rcutorture.c | 3 +++
> kernel/rcu/tasks.h | 25 +++++++++++++++++++++++++
> 3 files changed, 36 insertions(+)
>
> diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h
> index 86fce206560e..3353e3697645 100644
> --- a/kernel/rcu/rcu.h
> +++ b/kernel/rcu/rcu.h
> @@ -556,6 +556,14 @@ static inline unsigned long
> rcu_get_jiffies_lazy_flush(void) { return 0; }
> static inline void rcu_set_jiffies_lazy_flush(unsigned long j) { }
> #endif
>
> +#ifdef CONFIG_TASKS_RCU_GENERIC
> +void rcutaskstorture_get_gp_data(enum rcutorture_type test_type, int *flags,
> + unsigned long *gp_seq);
> +#else
> +static inline void rcutaskstorture_get_gp_data(enum rcutorture_type
> test_type, int *flags,
> + unsigned long *gp_seq) { }
> +#endif
> +
> #if defined(CONFIG_TREE_RCU)
> void rcutorture_get_gp_data(enum rcutorture_type test_type, int *flags,
> unsigned long *gp_seq);
> diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
> index dd7d5ba45740..91c03f37fd97 100644
> --- a/kernel/rcu/rcutorture.c
> +++ b/kernel/rcu/rcutorture.c
> @@ -2267,6 +2267,7 @@ rcu_torture_stats_print(void)
> &flags, &gp_seq);
> srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp,
> &flags, &gp_seq);
> + rcutaskstorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
> wtp = READ_ONCE(writer_task);
> pr_alert("??? Writer stall state %s(%d) g%lu f%#x ->state %#x
> cpu %d\n",
> rcu_torture_writer_state_getname(),
> @@ -3391,6 +3392,7 @@ rcu_torture_cleanup(void)
>
> rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
> srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq);
> + rcutaskstorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
> pr_alert("%s: End-test grace-period state: g%ld f%#x total-gps=%ld\n",
> cur_ops->name, (long)gp_seq, flags,
> rcutorture_seq_diff(gp_seq, start_gp_seq));
> @@ -3763,6 +3765,7 @@ rcu_torture_init(void)
> rcu_torture_print_module_parms(cur_ops, "Start of test");
> rcutorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
> srcutorture_get_gp_data(cur_ops->ttype, srcu_ctlp, &flags, &gp_seq);
> + rcutaskstorture_get_gp_data(cur_ops->ttype, &flags, &gp_seq);
> start_gp_seq = gp_seq;
> pr_alert("%s: Start-test grace-period state: g%ld f%#x\n",
> cur_ops->name, (long)gp_seq, flags);
> diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
> index e83adcdb49b5..b1254cf3c210 100644
> --- a/kernel/rcu/tasks.h
> +++ b/kernel/rcu/tasks.h
> @@ -2149,6 +2149,31 @@ late_initcall(rcu_tasks_verify_schedule_work);
> static void rcu_tasks_initiate_self_tests(void) { }
> #endif /* #else #ifdef CONFIG_PROVE_RCU */
>
> +void rcutaskstorture_get_gp_data(enum rcutorture_type test_type, int *flags,
> + unsigned long *gp_seq)
> +{
> + switch (test_type) {
> + case RCU_TASKS_FLAVOR:
> +#ifdef CONFIG_TASKS_RCU
> + *gp_seq = rcu_seq_current(&rcu_tasks.tasks_gp_seq);
> +#endif
> + break;
> + case RCU_TASKS_RUDE_FLAVOR:
> +#ifdef CONFIG_TASKS_RUDE_RCU
> + *gp_seq = rcu_seq_current(&rcu_tasks_rude.tasks_gp_seq);
> +#endif
> + break;
> + case RCU_TASKS_TRACING_FLAVOR:
> +#ifdef CONFIG_TASKS_TRACE_RCU
> + *gp_seq = rcu_seq_current(&rcu_tasks_trace.tasks_gp_seq);
> +#endif
> + break;
> + default:
> + break;
> + }
> +}
> +EXPORT_SYMBOL_GPL(rcutaskstorture_get_gp_data);
> +
> void __init tasks_cblist_init_generic(void)
> {
> lockdep_assert_irqs_disabled();
> --
> 2.17.1
>
