random: fix the tracepoint for get_random_bytes(_arch)

Fix a problem where get_random_bytes_arch() was calling the tracepoint
get_random_bytes().  So add a new tracepoint for
get_random_bytes_arch(), and make get_random_bytes() and
get_random_bytes_arch() call their correct tracepoint.

Also, add a new tracepoint for add_device_randomness()
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

drivers/char/random.c

@@ -711,6 +711,7 @@ void add_device_randomness(const void *buf, unsigned int size)
 {
 	unsigned long time = random_get_entropy() ^ jiffies;
 
+	trace_add_device_randomness(size, _RET_IP_);
 	mix_pool_bytes(&input_pool, buf, size, NULL);
 	mix_pool_bytes(&input_pool, &time, sizeof(time), NULL);
 	mix_pool_bytes(&nonblocking_pool, buf, size, NULL);
@@ -1127,6 +1128,7 @@ static ssize_t extract_entropy_user(struct entropy_store *r, void __user *buf,
  */
 void get_random_bytes(void *buf, int nbytes)
 {
+	trace_get_random_bytes(nbytes, _RET_IP_);
 	extract_entropy(&nonblocking_pool, buf, nbytes, 0, 0);
 }
 EXPORT_SYMBOL(get_random_bytes);
@@ -1145,7 +1147,7 @@ void get_random_bytes_arch(void *buf, int nbytes)
 {
 	char *p = buf;
 
-	trace_get_random_bytes(nbytes, _RET_IP_);
+	trace_get_random_bytes_arch(nbytes, _RET_IP_);
 	while (nbytes) {
 		unsigned long v;
 		int chunk = min(nbytes, (int)sizeof(unsigned long));

include/trace/events/random.h

@@ -7,6 +7,25 @@
 #include <linux/writeback.h>
 #include <linux/tracepoint.h>
 
+TRACE_EVENT(add_device_randomness,
+	TP_PROTO(int bytes, unsigned long IP),
+
+	TP_ARGS(bytes, IP),
+
+	TP_STRUCT__entry(
+		__field(	  int,	bytes			)
+		__field(unsigned long,	IP			)
+	),
+
+	TP_fast_assign(
+		__entry->bytes		= bytes;
+		__entry->IP		= IP;
+	),
+
+	TP_printk("bytes %d caller %pF",
+		__entry->bytes, (void *)__entry->IP)
+);
+
 DECLARE_EVENT_CLASS(random__mix_pool_bytes,
 	TP_PROTO(const char *pool_name, int bytes, unsigned long IP),
 
@@ -68,7 +87,7 @@ TRACE_EVENT(credit_entropy_bits,
 		  (void *)__entry->IP)
 );
 
-TRACE_EVENT(get_random_bytes,
+DECLARE_EVENT_CLASS(random__get_random_bytes,
 	TP_PROTO(int nbytes, unsigned long IP),
 
 	TP_ARGS(nbytes, IP),
@@ -86,6 +105,18 @@ TRACE_EVENT(get_random_bytes,
 	TP_printk("nbytes %d caller %pF", __entry->nbytes, (void *)__entry->IP)
 );
 
+DEFINE_EVENT(random__get_random_bytes, get_random_bytes,
+	TP_PROTO(int nbytes, unsigned long IP),
+
+	TP_ARGS(nbytes, IP)
+);
+
+DEFINE_EVENT(random__get_random_bytes, get_random_bytes_arch,
+	TP_PROTO(int nbytes, unsigned long IP),
+
+	TP_ARGS(nbytes, IP)
+);
+
 DECLARE_EVENT_CLASS(random__extract_entropy,
 	TP_PROTO(const char *pool_name, int nbytes, int entropy_count,
 		 unsigned long IP),