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| author | Waiman Long <longman@redhat.com> | 2022-06-14 08:06:20 -0400 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2022-06-21 15:49:38 -0700 |
| commit | e72ee5e1a866b85cb6c3d4c80a1125976020a7e8 (patch) | |
| tree | 99f230a3ff7f8113b469003d891683352cb9886c /kernel/rcu | |
| parent | 1cf1144e8473e8c3180ac8b91309e29b6acfd95f (diff) | |
| download | linux-e72ee5e1a866b85cb6c3d4c80a1125976020a7e8.tar.gz linux-e72ee5e1a866b85cb6c3d4c80a1125976020a7e8.tar.bz2 linux-e72ee5e1a866b85cb6c3d4c80a1125976020a7e8.zip | |
rcu-tasks: Use delayed_work to delay rcu_tasks_verify_self_tests()
Commit 2585014188d5 ("rcu-tasks: Be more patient for RCU Tasks
boot-time testing") fixes false positive rcu_tasks verification check
failure by repeating the test once every second until timeout using
schedule_timeout_uninterruptible().
Since rcu_tasks_verify_selft_tests() is called from do_initcalls()
as a late_initcall, this has the undesirable side effect of delaying
other late_initcall's queued after it by a second or more. Fix this by
instead using delayed_work to repeat the verification check.
Fixes: 2585014188d5 ("rcu-tasks: Be more patient for RCU Tasks boot-time testing")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/tasks.h | 37 |
1 files changed, 32 insertions, 5 deletions
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index fcbd0ec33c86..83c7e6620d40 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -1832,6 +1832,11 @@ static void rcu_tasks_initiate_self_tests(void) #endif } +/* + * Return: 0 - test passed + * 1 - test failed, but have not timed out yet + * -1 - test failed and timed out + */ static int rcu_tasks_verify_self_tests(void) { int ret = 0; @@ -1847,16 +1852,38 @@ static int rcu_tasks_verify_self_tests(void) ret = -1; break; } - schedule_timeout_uninterruptible(1); + ret = 1; + break; } } - - if (ret) - WARN_ON(1); + WARN_ON(ret < 0); return ret; } -late_initcall(rcu_tasks_verify_self_tests); + +/* + * Repeat the rcu_tasks_verify_self_tests() call once every second until the + * test passes or has timed out. + */ +static struct delayed_work rcu_tasks_verify_work; +static void rcu_tasks_verify_work_fn(struct work_struct *work __maybe_unused) +{ + int ret = rcu_tasks_verify_self_tests(); + + if (ret <= 0) + return; + + /* Test fails but not timed out yet, reschedule another check */ + schedule_delayed_work(&rcu_tasks_verify_work, HZ); +} + +static int rcu_tasks_verify_schedule_work(void) +{ + INIT_DELAYED_WORK(&rcu_tasks_verify_work, rcu_tasks_verify_work_fn); + rcu_tasks_verify_work_fn(NULL); + return 0; +} +late_initcall(rcu_tasks_verify_schedule_work); #else /* #ifdef CONFIG_PROVE_RCU */ static void rcu_tasks_initiate_self_tests(void) { } #endif /* #else #ifdef CONFIG_PROVE_RCU */ |