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>
This commit is contained in:
Mathieu Desnoyers 2008-09-30 01:51:12 -04:00 committed by Ingo Molnar
parent ca2db6cf30
commit 9a1e9693f5

View file

@ -356,6 +356,8 @@ int tracepoint_probe_register(const char *name, void *probe)
mutex_lock(&tracepoints_mutex); mutex_lock(&tracepoints_mutex);
entry = get_tracepoint(name); entry = get_tracepoint(name);
WARN_ON(!entry); WARN_ON(!entry);
if (entry->rcu_pending)
rcu_barrier_sched();
tracepoint_entry_free_old(entry, old); tracepoint_entry_free_old(entry, old);
end: end:
mutex_unlock(&tracepoints_mutex); mutex_unlock(&tracepoints_mutex);
@ -392,6 +394,8 @@ int tracepoint_probe_unregister(const char *name, void *probe)
entry = get_tracepoint(name); entry = get_tracepoint(name);
if (!entry) if (!entry)
goto end; goto end;
if (entry->rcu_pending)
rcu_barrier_sched();
tracepoint_entry_free_old(entry, old); tracepoint_entry_free_old(entry, old);
remove_tracepoint(name); /* Ignore busy error message */ remove_tracepoint(name); /* Ignore busy error message */
ret = 0; ret = 0;