Test an early call to start_poll_synchronize_srcu() and place it before the early test to call_srcu() on the same ssp.
After the later call to srcu_barrier(), we expect the first grace period completion to be visible by a subsequent call to poll_state_synchronize_srcu(). Report otherwise. Signed-off-by: Frederic Weisbecker <frede...@kernel.org> Cc: Boqun Feng <boqun.f...@gmail.com> Cc: Lai Jiangshan <jiangshan...@gmail.com> Cc: Neeraj Upadhyay <neer...@codeaurora.org> Cc: Josh Triplett <j...@joshtriplett.org> Cc: Joel Fernandes <j...@joelfernandes.org> Cc: Uladzislau Rezki <ure...@gmail.com> --- kernel/rcu/update.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index dd94a602a6d2..c21b38cc25e9 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -524,6 +524,7 @@ static void test_callback(struct rcu_head *r) } DEFINE_STATIC_SRCU(early_srcu); +static unsigned long early_srcu_cookie; struct early_boot_kfree_rcu { struct rcu_head rh; @@ -536,8 +537,10 @@ static void early_boot_test_call_rcu(void) struct early_boot_kfree_rcu *rhp; call_rcu(&head, test_callback); - if (IS_ENABLED(CONFIG_SRCU)) + if (IS_ENABLED(CONFIG_SRCU)) { + early_srcu_cookie = start_poll_synchronize_srcu(&early_srcu); call_srcu(&early_srcu, &shead, test_callback); + } rhp = kmalloc(sizeof(*rhp), GFP_KERNEL); if (!WARN_ON_ONCE(!rhp)) kfree_rcu(rhp, rh); @@ -563,6 +566,7 @@ static int rcu_verify_early_boot_tests(void) if (IS_ENABLED(CONFIG_SRCU)) { early_boot_test_counter++; srcu_barrier(&early_srcu); + WARN_ON_ONCE(!poll_state_synchronize_srcu(&early_srcu, early_srcu_cookie)); } } if (rcu_self_test_counter != early_boot_test_counter) { -- 2.25.1