Module Name: src
Committed By: riastradh
Date: Wed Apr 8 14:04:47 UTC 2015
Modified Files:
src/sys/kern: kern_rndq.c
Log Message:
Gather (some) rnd_skew state into a cacheline-aligned static struct.
To generate a diff of this commit:
cvs rdiff -u -r1.39 -r1.40 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:1.39 src/sys/kern/kern_rndq.c:1.40
--- src/sys/kern/kern_rndq.c:1.39 Wed Apr 8 13:45:01 2015
+++ src/sys/kern/kern_rndq.c Wed Apr 8 14:04:47 2015
@@ -1,4 +1,4 @@
-/* $NetBSD: kern_rndq.c,v 1.39 2015/04/08 13:45:01 riastradh Exp $ */
+/* $NetBSD: kern_rndq.c,v 1.40 2015/04/08 14:04:47 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 1.39 2015/04/08 13:45:01 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_rndq.c,v 1.40 2015/04/08 14:04:47 riastradh Exp $");
#include <sys/param.h>
#include <sys/atomic.h>
@@ -169,7 +169,6 @@ static krndsource_t rnd_source_anonymous
krndsource_t rnd_printf_source, rnd_autoconf_source;
void *rnd_process, *rnd_wakeup;
-struct callout skew_callout, skew_stop_callout;
void rnd_wakeup_readers(void);
static inline uint32_t rnd_counter(void);
@@ -432,46 +431,53 @@ rnd_dv_estimate(krndsource_t *rs, uint32
}
#if defined(__HAVE_CPU_COUNTER)
-kmutex_t rnd_skew_mtx;
+static struct {
+ kmutex_t lock;
+ struct callout callout;
+ struct callout stop_callout;
+} rnd_skew __cacheline_aligned;
-static void rnd_skew(void *);
+static void rnd_skew_intr(void *);
static void
rnd_skew_enable(krndsource_t *rs, bool enabled)
{
- mutex_spin_enter(&rnd_skew_mtx);
+
+ mutex_spin_enter(&rnd_skew.lock);
if (enabled) {
- rnd_skew(rs);
+ rnd_skew_intr(rs);
} else {
- callout_stop(&skew_callout);
+ callout_stop(&rnd_skew.callout);
}
- mutex_spin_exit(&rnd_skew_mtx);
+ mutex_spin_exit(&rnd_skew.lock);
}
static void
-rnd_skew_stop(void *arg)
+rnd_skew_stop_intr(void *arg)
{
- mutex_spin_enter(&rnd_skew_mtx);
- callout_stop(&skew_callout);
- mutex_spin_exit(&rnd_skew_mtx);
+
+ mutex_spin_enter(&rnd_skew.lock);
+ callout_stop(&rnd_skew.callout);
+ mutex_spin_exit(&rnd_skew.lock);
}
static void
rnd_skew_get(size_t bytes, void *priv)
{
krndsource_t *skewsrcp = priv;
+
if (RND_ENABLED(skewsrcp)) {
/* Measure for 30s */
- if (mutex_tryenter(&rnd_skew_mtx)) {
- callout_schedule(&skew_stop_callout, hz * 30);
- callout_schedule(&skew_callout, 1);
- mutex_spin_exit(&rnd_skew_mtx);
+ if (mutex_tryenter(&rnd_skew.lock)) {
+ callout_schedule(&rnd_skew.stop_callout, hz * 30);
+ callout_schedule(&rnd_skew.callout, 1);
+ mutex_spin_exit(&rnd_skew.lock);
}
}
}
static void
-rnd_skew(void *arg)
+rnd_skew_intr(void *arg)
{
static krndsource_t skewsrc;
static int live, flipflop;
@@ -484,7 +490,7 @@ rnd_skew(void *arg)
*/
if (__predict_false(!live)) {
/* XXX must be spin, taken with rndpool_mtx held */
- mutex_init(&rnd_skew_mtx, MUTEX_DEFAULT, IPL_VM);
+ 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,
@@ -494,18 +500,18 @@ rnd_skew(void *arg)
live = 1;
return;
}
- mutex_spin_enter(&rnd_skew_mtx);
+ mutex_spin_enter(&rnd_skew.lock);
flipflop = !flipflop;
if (RND_ENABLED(&skewsrc)) {
if (flipflop) {
rnd_add_uint32(&skewsrc, rnd_counter());
- callout_schedule(&skew_callout, hz / 10);
+ callout_schedule(&rnd_skew.callout, hz / 10);
} else {
- callout_schedule(&skew_callout, 1);
+ callout_schedule(&rnd_skew.callout, 1);
}
}
- mutex_spin_exit(&rnd_skew_mtx);
+ mutex_spin_exit(&rnd_skew.lock);
}
#endif
@@ -571,11 +577,11 @@ rnd_init(void)
*
*/
#if defined(__HAVE_CPU_COUNTER)
- callout_init(&skew_callout, CALLOUT_MPSAFE);
- callout_init(&skew_stop_callout, CALLOUT_MPSAFE);
- callout_setfunc(&skew_callout, rnd_skew, NULL);
- callout_setfunc(&skew_stop_callout, rnd_skew_stop, NULL);
- rnd_skew(NULL);
+ 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);
+ rnd_skew_intr(NULL);
#endif
rnd_printf_verbose("rnd: initialised (%u)%s", RND_POOLBITS,
