[lkml]   [2022]   [Jul]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
Patch in this message
Subject[PATCH v2] rcu-tasks: Make RCU Tasks Trace checking for userspace execution
For RCU tasks trace, the userspace execution is also a valid quiescent
state, if the task is in userspace, the ->trc_reader_nesting should be
zero and if the ->trc_reader_special.b.need_qs is not set, set the
tasks ->trc_reader_special.b.need_qs is TRC_NEED_QS_CHECKED, this cause
grace-period kthread remove it from holdout list if it remains here.

This commit add rcu_tasks_trace_qs() to rcu_flavor_sched_clock_irq()
when the kernel built with no PREEMPT_RCU.

Signed-off-by: Zqiang <>
Fix build error due to undeclared rcu_tasks_trace_qs(), note in no-PREEMPT_RCU
kernel, the RCU Tasks is replaced by RCU, so rcu_note_voluntary_context_switch()
only include rcu_tasks_trace_qs().

kernel/rcu/tree_plugin.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 4152816dd29f..5fb0b2dd24fd 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -976,7 +976,7 @@ static void rcu_flavor_sched_clock_irq(int user)
* neither access nor modify, at least not while the
* corresponding CPU is online.
+ rcu_note_voluntary_context_switch(current);
 \ /
  Last update: 2022-07-18 02:12    [W:0.046 / U:2.824 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site