From: "Paul E. McKenney" <paulmck@kernel.org>
To: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, kernel-team@fb.com,
mingo@kernel.org, jiangshanlai@gmail.com,
akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org,
rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com,
fweisbec@gmail.com, oleg@redhat.com, joel@joelfernandes.org,
"Paul E. McKenney" <paulmck@kernel.org>
Subject: [PATCH tip/core/rcu 05/19] rcu: Add ->rt_priority and ->gp_start to show_rcu_gp_kthreads() output
Date: Tue, 11 May 2021 15:52:50 -0700 [thread overview]
Message-ID: <20210511225304.2893154-5-paulmck@kernel.org> (raw)
In-Reply-To: <20210511225241.GA2893003@paulmck-ThinkPad-P17-Gen-1>
This commit adds ->rt_priority and ->gp_start to show_rcu_gp_kthreads()
output in order to better diagnose RCU priority boosting failures.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
kernel/rcu/tree_stall.h | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
index 59b95cc5cbdf..fb4702570316 100644
--- a/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@ -726,6 +726,7 @@ void show_rcu_gp_kthreads(void)
unsigned long j;
unsigned long ja;
unsigned long jr;
+ unsigned long js;
unsigned long jw;
struct rcu_data *rdp;
struct rcu_node *rnp;
@@ -734,11 +735,12 @@ void show_rcu_gp_kthreads(void)
j = jiffies;
ja = j - data_race(rcu_state.gp_activity);
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 delta ->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_flags %#x\n",
rcu_state.name, gp_state_getname(rcu_state.gp_state),
- rcu_state.gp_state, t ? t->state : 0x1ffffL,
- ja, jr, jw, (long)data_race(rcu_state.gp_wake_seq),
+ 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_flags));
--
2.31.1.189.g2e36527f23
next prev parent reply other threads:[~2021-05-11 22:53 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-11 22:52 [PATCH tip/core/rcu 0/19] Miscellaneous fixes for v5.14 Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 01/19] rcu: Fix typo in comment: kthead -> kthread Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 02/19] rcu: Remove the unused rcu_irq_exit_preempt() function Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 03/19] rcu: Improve tree.c comments and add code cleanups Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 04/19] rcu: Invoke rcu_spawn_core_kthreads() from rcu_spawn_gp_kthread() Paul E. McKenney
2021-05-11 22:52 ` Paul E. McKenney [this message]
2021-05-11 22:52 ` [PATCH tip/core/rcu 06/19] rcu: Add ->gp_max to show_rcu_gp_kthreads() output Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 07/19] lockdep: Explicitly flag likely false-positive report Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 08/19] rcu: Reject RCU_LOCKDEP_WARN() false positives Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 09/19] rcu: Add quiescent states and boost states to show_rcu_gp_kthreads() output Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 10/19] rcu: Make RCU priority boosting work on single-CPU rcu_node structures Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 11/19] rcu: Make show_rcu_gp_kthreads() dump rcu_node structures blocking GP Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 12/19] rcu: Restrict RCU_STRICT_GRACE_PERIOD to at most four CPUs Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 13/19] rcu: Make rcu_gp_cleanup() be noinline for tracing Paul E. McKenney
2021-05-11 22:52 ` [PATCH tip/core/rcu 14/19] rcu: Point to documentation of ordering guarantees Paul E. McKenney
2021-05-11 22:53 ` [PATCH tip/core/rcu 15/19] rcu: Create an unrcu_pointer() to remove __rcu from a pointer Paul E. McKenney
2021-05-11 22:53 ` [PATCH tip/core/rcu 16/19] sched/isolation: reconcile rcu_nocbs= and nohz_full= Paul E. McKenney
2021-05-11 22:53 ` [PATCH tip/core/rcu 17/19] rcu: Improve comments describing RCU read-side critical sections Paul E. McKenney
2021-05-11 22:53 ` [PATCH tip/core/rcu 18/19] rcu: Remove obsolete rcu_read_unlock() deadlock commentary Paul E. McKenney
2021-05-11 22:53 ` [PATCH tip/core/rcu 19/19] rcu: Add missing __releases() annotation Paul E. McKenney
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