[PATCH, RFC 05/12] random: fix the tracepoint for get_random_bytes(_arch)

From: Theodore Ts'o
Date: Sun Sep 22 2013 - 16:40:16 EST


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: "Theodore Ts'o" <tytso@xxxxxxx>
---
drivers/char/random.c | 5 ++++-
include/trace/events/random.h | 33 ++++++++++++++++++++++++++++++++-
2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 75f04d5..391b05a 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -708,7 +708,9 @@ struct timer_rand_state {
void add_device_randomness(const void *buf, unsigned int size)
{
unsigned long time = get_cycles() ^ jiffies;
+ unsigned long flags;

+ 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);
@@ -1125,6 +1127,7 @@ 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);
@@ -1143,7 +1146,7 @@ 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));
diff --git a/include/trace/events/random.h b/include/trace/events/random.h
index 422df19..2ffcaec 100644
--- a/include/trace/events/random.h
+++ b/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),
--
1.7.12.rc0.22.gcdd159b

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/