The following commit has been merged into the core/rcu branch of tip:
Commit-ID: 27ba76e164fc83ffe6ceeb0415c427ad1191af6c
Gitweb: https://git.kernel.org/tip/27ba76e164fc83ffe6ceeb0415c427ad1191af6c
Author: Paul E. McKenney <paulmck@xxxxxxxxxx>
AuthorDate: Sun, 04 Apr 2021 17:23:36 -07:00
Committer: Paul E. McKenney <paulmck@xxxxxxxxxx>
CommitterDate: Mon, 10 May 2021 16:22:54 -07:00
rcu: Add ->gp_max to show_rcu_gp_kthreads() output
This commit adds ->gp_max to show_rcu_gp_kthreads() output in order to
better diagnose RCU priority boosting failures.
Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx>
---
kernel/rcu/tree_stall.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
index fb47025..a4e2bb3 100644
--- a/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@ -737,12 +737,13 @@ void show_rcu_gp_kthreads(void)
jr = j - data_race(rcu_state.gp_req_activity);
js = j - data_race(rcu_state.gp_start);
jw = j - data_race(rcu_state.gp_wake_time);
- pr_info("%s: wait state: %s(%d) ->state: %#lx ->rt_priority %u delta ->gp_start %lu ->gp_activity %lu ->gp_req_activity %lu ->gp_wake_time %lu ->gp_wake_seq %ld ->gp_seq %ld ->gp_seq_needed %ld ->gp_flags %#x\n",
+ pr_info("%s: wait state: %s(%d) ->state: %#lx ->rt_priority %u delta ->gp_start %lu ->gp_activity %lu ->gp_req_activity %lu ->gp_wake_time %lu ->gp_wake_seq %ld ->gp_seq %ld ->gp_seq_needed %ld ->gp_max %lu ->gp_flags %#x\n",
rcu_state.name, gp_state_getname(rcu_state.gp_state),
rcu_state.gp_state, t ? t->state : 0x1ffffL, t ? t->rt_priority : 0xffU,
js, ja, jr, jw, (long)data_race(rcu_state.gp_wake_seq),
(long)data_race(rcu_state.gp_seq),
(long)data_race(rcu_get_root()->gp_seq_needed),
+ data_race(rcu_state.gp_max),
data_race(rcu_state.gp_flags));
rcu_for_each_node_breadth_first(rnp) {
if (ULONG_CMP_GE(READ_ONCE(rcu_state.gp_seq),
|