1 files changed, 19 insertions, 8 deletions

diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c
index 1848ce7e2976..dffef52a807b 100644
--- a/kernel/tracepoint.c
+++ b/kernel/tracepoint.c
@@ -34,9 +34,13 @@ enum tp_transition_sync {
 
 struct tp_transition_snapshot {
 	unsigned long rcu;
+	unsigned long srcu_gp;
 	bool ongoing;
 };
 
+DEFINE_SRCU_FAST(tracepoint_srcu);
+EXPORT_SYMBOL_GPL(tracepoint_srcu);
+
 /* Protected by tracepoints_mutex */
 static struct tp_transition_snapshot tp_transition_snapshot[_NR_TP_TRANSITION_SYNC];
 
@@ -46,6 +50,7 @@ static void tp_rcu_get_state(enum tp_transition_sync sync)
 
 	/* Keep the latest get_state snapshot. */
 	snapshot->rcu = get_state_synchronize_rcu();
+	snapshot->srcu_gp = start_poll_synchronize_srcu(&tracepoint_srcu);
 	snapshot->ongoing = true;
 }
 
@@ -56,6 +61,8 @@ static void tp_rcu_cond_sync(enum tp_transition_sync sync)
 	if (!snapshot->ongoing)
 		return;
 	cond_synchronize_rcu(snapshot->rcu);
+	if (!poll_state_synchronize_srcu(&tracepoint_srcu, snapshot->srcu_gp))
+		synchronize_srcu(&tracepoint_srcu);
 	snapshot->ongoing = false;
 }
 
@@ -96,8 +103,7 @@ static void tp_stub_func(void)
 
 static inline void *allocate_probes(int count)
 {
-	struct tp_probes *p  = kmalloc(struct_size(p, probes, count),
-				       GFP_KERNEL);
+	struct tp_probes *p  = kmalloc_flex(*p, probes, count);
 	return p == NULL ? NULL : p->probes;
 }
 
@@ -112,10 +118,13 @@ static inline void release_probes(struct tracepoint *tp, struct tracepoint_func
 		struct tp_probes *tp_probes = container_of(old,
 			struct tp_probes, probes[0]);
 
-		if (tracepoint_is_faultable(tp))
-			call_rcu_tasks_trace(&tp_probes->rcu, rcu_free_old_probes);
-		else
-			call_rcu(&tp_probes->rcu, rcu_free_old_probes);
+		if (tracepoint_is_faultable(tp)) {
+			call_rcu_tasks_trace(&tp_probes->rcu,
+					     rcu_free_old_probes);
+		} else {
+			call_srcu(&tracepoint_srcu, &tp_probes->rcu,
+				  rcu_free_old_probes);
+		}
 	}
 }
 
@@ -127,7 +136,7 @@ static void debug_print_probes(struct tracepoint_func *funcs)
 		return;
 
 	for (i = 0; funcs[i].func; i++)
-		printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func);
+		printk(KERN_DEBUG "Probe %d : %pSb\n", i, funcs[i].func);
 }
 
 static struct tracepoint_func *
@@ -291,6 +300,8 @@ static int tracepoint_add_func(struct tracepoint *tp,
 			lockdep_is_held(&tracepoints_mutex));
 	old = func_add(&tp_funcs, func, prio);
 	if (IS_ERR(old)) {
+		if (tp->ext && tp->ext->unregfunc && !static_key_enabled(&tp->key))
+			tp->ext->unregfunc();
 		WARN_ON_ONCE(warn && PTR_ERR(old) != -ENOMEM);
 		return PTR_ERR(old);
 	}
@@ -605,7 +616,7 @@ static int tracepoint_module_coming(struct module *mod)
 	if (trace_module_has_bad_taint(mod))
 		return 0;
 
-	tp_mod = kmalloc(sizeof(struct tp_module), GFP_KERNEL);
+	tp_mod = kmalloc_obj(struct tp_module);
 	if (!tp_mod)
 		return -ENOMEM;
 	tp_mod->mod = mod;