diff options
Diffstat (limited to 'kernel/rcu/tree_exp.h')
| -rw-r--r-- | kernel/rcu/tree_exp.h | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h index 4c2a0189e748..7be3e085ddd6 100644 --- a/kernel/rcu/tree_exp.h +++ b/kernel/rcu/tree_exp.h @@ -10,6 +10,7 @@ #include <linux/lockdep.h> static void rcu_exp_handler(void *unused); +static int rcu_print_task_exp_stall(struct rcu_node *rnp); /* * Record the start of an expedited grace period. @@ -670,6 +671,27 @@ static void sync_sched_exp_online_cleanup(int cpu) { } +/* + * Scan the current list of tasks blocked within RCU read-side critical + * sections, printing out the tid of each that is blocking the current + * expedited grace period. + */ +static int rcu_print_task_exp_stall(struct rcu_node *rnp) +{ + struct task_struct *t; + int ndetected = 0; + + if (!rnp->exp_tasks) + return 0; + t = list_entry(rnp->exp_tasks->prev, + struct task_struct, rcu_node_entry); + list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) { + pr_cont(" P%d", t->pid); + ndetected++; + } + return ndetected; +} + #else /* #ifdef CONFIG_PREEMPT_RCU */ /* Invoked on each online non-idle CPU for expedited quiescent state. */ @@ -709,6 +731,16 @@ static void sync_sched_exp_online_cleanup(int cpu) WARN_ON_ONCE(ret); } +/* + * Because preemptible RCU does not exist, we never have to check for + * tasks blocked within RCU read-side critical sections that are + * blocking the current expedited grace period. + */ +static int rcu_print_task_exp_stall(struct rcu_node *rnp) +{ + return 0; +} + #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ /** |