tracepoints: fix reentrancy
The tracepoints had the same problem markers did have wrt reentrancy. Apply a
similar fix using a rcu_barrier after each tracepoint mutex lock.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index db39961..f2b7c28 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -356,6 +356,8 @@
mutex_lock(&tracepoints_mutex);
entry = get_tracepoint(name);
WARN_ON(!entry);
+ if (entry->rcu_pending)
+ rcu_barrier_sched();
tracepoint_entry_free_old(entry, old);
end:
mutex_unlock(&tracepoints_mutex);
@@ -392,6 +394,8 @@
entry = get_tracepoint(name);
if (!entry)
goto end;
+ if (entry->rcu_pending)
+ rcu_barrier_sched();
tracepoint_entry_free_old(entry, old);
remove_tracepoint(name); /* Ignore busy error message */
ret = 0;