cc99a310ca
The rcu_report_unblock_qs_rnp() function is invoked when the last task blocking the current grace period exits its outermost RCU read-side critical section. Previously, this was called only from rcu_read_unlock_special(), and was therefore defined only when CONFIG_RCU_PREEMPT=y. However, this function will be invoked even when CONFIG_RCU_PREEMPT=n once CPU-hotplug operations are processed only at the beginnings of RCU grace periods. The reason for this change is that the last task on a given leaf rcu_node structure's ->blkd_tasks list might well exit its RCU read-side critical section between the time that recent CPU-hotplug operations were applied and when the new grace period was initialized. This situation could result in RCU waiting forever on that leaf rcu_node structure, because if all that structure's CPUs were already offline, there would be no quiescent-state events to drive that structure's part of the grace period. This commit therefore moves rcu_report_unblock_qs_rnp() to common code that is built unconditionally so that the quiescent-state-forcing code can clean up after this situation, avoiding the grace-period stall. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> |
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| .. | ||
| Makefile | ||
| rcu.h | ||
| rcutorture.c | ||
| srcu.c | ||
| tiny.c | ||
| tiny_plugin.h | ||
| tree.c | ||
| tree.h | ||
| tree_plugin.h | ||
| tree_trace.c | ||
| update.c | ||