Module Name: src
Committed By: riastradh
Date: Wed Apr 8 14:08:49 UTC 2015
Modified Files:
src/sys/kern: kern_rndq.c
Log Message:
Don't do broken lazy initialization. Just do it up front.
To generate a diff of this commit:
cvs rdiff -u -r1.40 -r1.41 src/sys/kern/kern_rndq.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/kern_rndq.c
diff -u src/sys/kern/kern_rndq.c:1.40 src/sys/kern/kern_rndq.c:1.41
--- src/sys/kern/kern_rndq.c:1.40 Wed Apr 8 14:04:47 2015
+++ src/sys/kern/kern_rndq.c Wed Apr 8 14:08:49 2015
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_rndq.c,v 1.40 2015/04/08 14:04:47 riastradh Exp $ */
+/* $NetBSD: kern_rndq.c,v 1.41 2015/04/08 14:08:49 riastradh Exp $ */
/*-
* Copyright (c) 1997-2013 The NetBSD Foundation, Inc.
@@ -32,7 +32,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_rndq.c,v 1.40 2015/04/08 14:04:47 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_rndq.c,v 1.41 2015/04/08 14:08:49 riastradh Exp $");
#include <sys/param.h>
#include <sys/atomic.h>
@@ -435,6 +435,7 @@ static struct {
kmutex_t lock;
struct callout callout;
struct callout stop_callout;
+ krndsource_t source;
} rnd_skew __cacheline_aligned;
static void rnd_skew_intr(void *);
@@ -466,6 +467,7 @@ rnd_skew_get(size_t bytes, void *priv)
{
krndsource_t *skewsrcp = priv;
+ KASSERT(skewsrcp == &rnd_skew.source);
if (RND_ENABLED(skewsrcp)) {
/* Measure for 30s */
if (mutex_tryenter(&rnd_skew.lock)) {
@@ -479,8 +481,7 @@ rnd_skew_get(size_t bytes, void *priv)
static void
rnd_skew_intr(void *arg)
{
- static krndsource_t skewsrc;
- static int live, flipflop;
+ static int flipflop;
/*
* Even on systems with seemingly stable clocks, the
@@ -488,24 +489,12 @@ rnd_skew_intr(void *arg)
* about every 2 calls.
*
*/
- if (__predict_false(!live)) {
- /* XXX must be spin, taken with rndpool_mtx held */
- mutex_init(&rnd_skew.lock, MUTEX_DEFAULT, IPL_VM);
- rndsource_setcb(&skewsrc, rnd_skew_get, &skewsrc);
- rndsource_setenable(&skewsrc, rnd_skew_enable);
- rnd_attach_source(&skewsrc, "callout", RND_TYPE_SKEW,
- RND_FLAG_COLLECT_VALUE|
- RND_FLAG_ESTIMATE_VALUE|
- RND_FLAG_HASCB|RND_FLAG_HASENABLE);
- live = 1;
- return;
- }
mutex_spin_enter(&rnd_skew.lock);
flipflop = !flipflop;
- if (RND_ENABLED(&skewsrc)) {
+ if (RND_ENABLED(&rnd_skew.source)) {
if (flipflop) {
- rnd_add_uint32(&skewsrc, rnd_counter());
+ rnd_add_uint32(&rnd_skew.source, rnd_counter());
callout_schedule(&rnd_skew.callout, hz / 10);
} else {
callout_schedule(&rnd_skew.callout, 1);
@@ -577,10 +566,17 @@ rnd_init(void)
*
*/
#if defined(__HAVE_CPU_COUNTER)
+ /* IPL_VM because taken while rndpool_mtx is held. */
+ mutex_init(&rnd_skew.lock, MUTEX_DEFAULT, IPL_VM);
callout_init(&rnd_skew.callout, CALLOUT_MPSAFE);
callout_init(&rnd_skew.stop_callout, CALLOUT_MPSAFE);
callout_setfunc(&rnd_skew.callout, rnd_skew_intr, NULL);
callout_setfunc(&rnd_skew.stop_callout, rnd_skew_stop_intr, NULL);
+ rndsource_setcb(&rnd_skew.source, rnd_skew_get, &rnd_skew.source);
+ rndsource_setenable(&rnd_skew.source, rnd_skew_enable);
+ rnd_attach_source(&rnd_skew.source, "callout", RND_TYPE_SKEW,
+ RND_FLAG_COLLECT_VALUE|RND_FLAG_ESTIMATE_VALUE|
+ RND_FLAG_HASCB|RND_FLAG_HASENABLE);
rnd_skew_intr(NULL);
#endif
