diff options
| author | Paul E. McKenney <paulmck@kernel.org> | 2023-08-15 15:46:32 -0700 |
|---|---|---|
| committer | Frederic Weisbecker <frederic@kernel.org> | 2023-09-11 22:10:47 +0200 |
| commit | 5b404fdabacf4bee92d8c66013402a85f18a6a10 (patch) | |
| tree | 0dea17abbdfb376809a7c73d433697c9d63b346c /kernel/rcu/tree_exp.h | |
| parent | 243d5ab34446854ceca55146fc0d837655657f8e (diff) | |
rcu: Add RCU CPU stall notifier
It is sometimes helpful to have a way for the subsystem causing
the stall to dump its state when an RCU CPU stall occurs. This
commit therefore bases rcu_stall_chain_notifier_register() and
rcu_stall_chain_notifier_unregister() on atomic notifiers in order to
provide this functionality.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Diffstat (limited to 'kernel/rcu/tree_exp.h')
| -rw-r--r-- | kernel/rcu/tree_exp.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h index 8239b39d945b..6d7cea5d591f 100644 --- a/kernel/rcu/tree_exp.h +++ b/kernel/rcu/tree_exp.h @@ -621,10 +621,14 @@ static void synchronize_rcu_expedited_wait(void) } for (;;) { + unsigned long j; + if (synchronize_rcu_expedited_wait_once(jiffies_stall)) return; if (rcu_stall_is_suppressed()) continue; + j = jiffies; + rcu_stall_notifier_call_chain(RCU_STALL_NOTIFY_EXP, (void *)(j - jiffies_start)); trace_rcu_stall_warning(rcu_state.name, TPS("ExpeditedStall")); pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {", rcu_state.name); @@ -647,7 +651,7 @@ static void synchronize_rcu_expedited_wait(void) } } pr_cont(" } %lu jiffies s: %lu root: %#lx/%c\n", - jiffies - jiffies_start, rcu_state.expedited_sequence, + j - jiffies_start, rcu_state.expedited_sequence, data_race(rnp_root->expmask), ".T"[!!data_race(rnp_root->exp_tasks)]); if (ndetected) { |