diff options
| author | Paul E. McKenney <paulmck@linux.ibm.com> | 2018-12-10 16:09:49 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.ibm.com> | 2019-01-25 15:29:57 -0800 |
| commit | fd897573fa4cfe66ebddf5f4444f36710cf0cad0 (patch) | |
| tree | 5a1c085f7bcfb968f04ac023da8b049f3aeb5cb8 /kernel/rcu/tree.h | |
| parent | a9fefdb257259ac2f0f5fcd916edecc5c9427635 (diff) | |
rcu: Improve diagnostics for failed RCU grace-period start
If a grace period fails to start (for example, because you commented
out the last two lines of rcu_accelerate_cbs_unlocked()), rcu_core()
will invoke rcu_check_gp_start_stall(), which will notice and complain.
However, this complaint is lacking crucial debugging information such
as when the last wakeup executed and what the value of ->gp_seq was at
that time. This commit therefore removes the current pr_alert() from
rcu_check_gp_start_stall(), instead invoking show_rcu_gp_kthreads(),
which has been updated to print the needed information, which is collected
by rcu_gp_kthread_wake().
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Diffstat (limited to 'kernel/rcu/tree.h')
| -rw-r--r-- | kernel/rcu/tree.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 008c356c7033..1f2ada7ef7d7 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -309,6 +309,8 @@ struct rcu_state { struct swait_queue_head gp_wq; /* Where GP task waits. */ short gp_flags; /* Commands for GP task. */ short gp_state; /* GP kthread sleep state. */ + unsigned long gp_wake_time; /* Last GP kthread wake. */ + unsigned long gp_wake_seq; /* ->gp_seq at ^^^. */ /* End of fields guarded by root rcu_node's lock. */ |