aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorPaul E. McKenney <paulmck@kernel.org>2022-07-18 10:57:26 -0700
committerPaul E. McKenney <paulmck@kernel.org>2022-08-31 05:10:55 -0700
commitd6ad60635cafe900bcd11ad588d8accb36c36b1b (patch)
treeb05a0f3f4e6f857d726022f1b54bd472a37e2265
parentrcu-tasks: Convert RCU_LOCKDEP_WARN() to WARN_ONCE() (diff)
downloadlinux-dev-d6ad60635cafe900bcd11ad588d8accb36c36b1b.tar.xz
linux-dev-d6ad60635cafe900bcd11ad588d8accb36c36b1b.zip
rcu-tasks: Ensure RCU Tasks Trace loops have quiescent states
The RCU Tasks Trace grace-period kthread loops across all CPUs, and there can be quite a few CPUs, with some commercially available systems sporting well over a thousand of them. Some of these loops can feature IPIs, which can take some time. This commit therefore places a call to cond_resched_tasks_rcu_qs() in each such loop. Link: https://docs.google.com/document/d/1V0YnG1HTWMt9WHJjroiJL9lf-hMrud4v8Fn3fhyY0cI/edit?usp=sharing Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
-rw-r--r--kernel/rcu/tasks.h3
1 files changed, 3 insertions, 0 deletions
diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 469bf2a3b505..f5bf6fb430da 100644
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -1500,6 +1500,7 @@ static void rcu_tasks_trace_pregp_step(struct list_head *hop)
if (rcu_tasks_trace_pertask_prep(t, true))
trc_add_holdout(t, hop);
rcu_read_unlock();
+ cond_resched_tasks_rcu_qs();
}
// Only after all running tasks have been accounted for is it
@@ -1520,6 +1521,7 @@ static void rcu_tasks_trace_pregp_step(struct list_head *hop)
raw_spin_lock_irqsave_rcu_node(rtpcp, flags);
}
raw_spin_unlock_irqrestore_rcu_node(rtpcp, flags);
+ cond_resched_tasks_rcu_qs();
}
// Re-enable CPU hotplug now that the holdout list is populated.
@@ -1619,6 +1621,7 @@ static void check_all_holdout_tasks_trace(struct list_head *hop,
trc_del_holdout(t);
else if (needreport)
show_stalled_task_trace(t, firstreport);
+ cond_resched_tasks_rcu_qs();
}
// Re-enable CPU hotplug now that the holdout list scan has completed.