| Message ID | 20220719021513.432306-1-qiang1.zhang@intel.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v3] rcu-tasks: Make RCU Tasks Trace checking for userspace execution | expand |
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); rcu_qs(); } }
For RCU tasks trace, the userspace execution is also a valid quiescent state, when scheduling-clock interrupt handler interrupts the task is in userspace. if the ->trc_reader_nesting is zero, and 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. If the ->trc_reader_nesting is not zero(if one of the functions in the scheduling-clock interrupt handler were traced/instrumented), and starts a new RCU tasks trace grace period, when grace period kthread scan running tasks on each CPU, this running uasks will be inserted into hold list. 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 <qiang1.zhang@intel.com> --- v1->v2: 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(). v2->v3: Modify commit information. kernel/rcu/tree_plugin.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)