From: cheloha <cheloha@openbsd.org>
Date: Thu, 14 Sep 2023 19:39:47 +0000 (+0000)
Subject: clockintr: replace CL_RNDSTAT with global variable statclock_is_randomized
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=b3ef18bd4c7a0758527134a7efc06e1f6d79ef23;p=openbsd

clockintr: replace CL_RNDSTAT with global variable statclock_is_randomized

In order to separate the statclock from the clock interrupt subsystem
we need to move all statclock state out into the broader kernel.

Start by replacing the CL_RNDSTAT flag with a new global variable,
"statclock_is_randomized", in kern_clock.c.  Update all clockintr_init()
callers to set the boolean instead of passing the flag.

Thread: https://marc.info/?l=openbsd-tech&m=169428749720476&w=2
---

diff --git a/sys/arch/amd64/amd64/lapic.c b/sys/arch/amd64/amd64/lapic.c
index 4e7182ecb5e..6f9c2ace887 100644
--- a/sys/arch/amd64/amd64/lapic.c
+++ b/sys/arch/amd64/amd64/lapic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lapic.c,v 1.69 2023/08/23 01:55:46 cheloha Exp $	*/
+/*	$OpenBSD: lapic.c,v 1.70 2023/09/14 19:39:47 cheloha Exp $	*/
 /* $NetBSD: lapic.c,v 1.2 2003/05/08 01:04:35 fvdl Exp $ */
 
 /*-
@@ -498,7 +498,8 @@ lapic_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 }
 
 
diff --git a/sys/arch/arm/cortex/agtimer.c b/sys/arch/arm/cortex/agtimer.c
index 88e201abe8a..106cb4804c0 100644
--- a/sys/arch/arm/cortex/agtimer.c
+++ b/sys/arch/arm/cortex/agtimer.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: agtimer.c,v 1.19 2023/08/23 01:55:46 cheloha Exp $ */
+/* $OpenBSD: agtimer.c,v 1.20 2023/09/14 19:39:47 cheloha Exp $ */
 /*
  * Copyright (c) 2011 Dale Rahn <drahn@openbsd.org>
  * Copyright (c) 2013 Patrick Wildt <patrick@blueri.se>
@@ -230,7 +230,8 @@ agtimer_cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	if (sc->sc_ticks_per_second != agtimer_frequency) {
 		agtimer_set_clockrate(agtimer_frequency);
diff --git a/sys/arch/arm/cortex/amptimer.c b/sys/arch/arm/cortex/amptimer.c
index 299f9fe8c61..1fb5695c00b 100644
--- a/sys/arch/arm/cortex/amptimer.c
+++ b/sys/arch/arm/cortex/amptimer.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: amptimer.c,v 1.18 2023/08/23 01:55:46 cheloha Exp $ */
+/* $OpenBSD: amptimer.c,v 1.19 2023/09/14 19:39:47 cheloha Exp $ */
 /*
  * Copyright (c) 2011 Dale Rahn <drahn@openbsd.org>
  *
@@ -287,7 +287,8 @@ amptimer_cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = hz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	if (sc->sc_ticks_per_second != amptimer_frequency) {
 		amptimer_set_clockrate(amptimer_frequency);
diff --git a/sys/arch/arm64/dev/agtimer.c b/sys/arch/arm64/dev/agtimer.c
index 14fb14f0088..12b21c2a79b 100644
--- a/sys/arch/arm64/dev/agtimer.c
+++ b/sys/arch/arm64/dev/agtimer.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: agtimer.c,v 1.26 2023/08/23 01:55:46 cheloha Exp $ */
+/* $OpenBSD: agtimer.c,v 1.27 2023/09/14 19:39:47 cheloha Exp $ */
 /*
  * Copyright (c) 2011 Dale Rahn <drahn@openbsd.org>
  * Copyright (c) 2013 Patrick Wildt <patrick@blueri.se>
@@ -293,7 +293,8 @@ agtimer_cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	if (sc->sc_ticks_per_second != agtimer_frequency) {
 		agtimer_set_clockrate(agtimer_frequency);
diff --git a/sys/arch/armv7/omap/dmtimer.c b/sys/arch/armv7/omap/dmtimer.c
index 985428bd6d3..5aaee39405c 100644
--- a/sys/arch/armv7/omap/dmtimer.c
+++ b/sys/arch/armv7/omap/dmtimer.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dmtimer.c,v 1.20 2023/08/23 01:55:46 cheloha Exp $	*/
+/*	$OpenBSD: dmtimer.c,v 1.21 2023/09/14 19:39:47 cheloha Exp $	*/
 /*
  * Copyright (c) 2007,2009 Dale Rahn <drahn@openbsd.org>
  * Copyright (c) 2013 Raphael Graf <r@undefined.ch>
@@ -232,7 +232,8 @@ dmtimer_cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	sc->sc_ticks_per_second = TIMER_FREQUENCY; /* 32768 */
 	sc->sc_nsec_cycle_ratio =
diff --git a/sys/arch/armv7/omap/gptimer.c b/sys/arch/armv7/omap/gptimer.c
index 72cf3e0566a..8ca887098fd 100644
--- a/sys/arch/armv7/omap/gptimer.c
+++ b/sys/arch/armv7/omap/gptimer.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: gptimer.c,v 1.21 2023/08/23 01:55:46 cheloha Exp $ */
+/* $OpenBSD: gptimer.c,v 1.22 2023/09/14 19:39:47 cheloha Exp $ */
 /*
  * Copyright (c) 2007,2009 Dale Rahn <drahn@openbsd.org>
  *
@@ -198,7 +198,8 @@ gptimer_cpu_initclocks(void)
 {
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	gptimer_nsec_cycle_ratio = TIMER_FREQUENCY * (1ULL << 32) / 1000000000;
 	gptimer_nsec_max = UINT64_MAX / gptimer_nsec_cycle_ratio;
diff --git a/sys/arch/armv7/sunxi/sxitimer.c b/sys/arch/armv7/sunxi/sxitimer.c
index 81b36f9c23b..9bee18a9e19 100644
--- a/sys/arch/armv7/sunxi/sxitimer.c
+++ b/sys/arch/armv7/sunxi/sxitimer.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sxitimer.c,v 1.22 2023/08/23 01:55:46 cheloha Exp $	*/
+/*	$OpenBSD: sxitimer.c,v 1.23 2023/09/14 19:39:47 cheloha Exp $	*/
 /*
  * Copyright (c) 2007,2009 Dale Rahn <drahn@openbsd.org>
  * Copyright (c) 2013 Raphael Graf <r@undefined.ch>
@@ -180,7 +180,8 @@ sxitimer_attach(struct device *parent, struct device *self, void *aux)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	/* stop timer, and set clk src */
 	bus_space_write_4(sxitimer_iot, sxitimer_ioh,
diff --git a/sys/arch/hppa/dev/clock.c b/sys/arch/hppa/dev/clock.c
index 2bae218e3c8..3e54c5034ca 100644
--- a/sys/arch/hppa/dev/clock.c
+++ b/sys/arch/hppa/dev/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.37 2023/08/23 01:55:46 cheloha Exp $	*/
+/*	$OpenBSD: clock.c,v 1.38 2023/09/14 19:39:48 cheloha Exp $	*/
 
 /*
  * Copyright (c) 1998-2003 Michael Shalayeff
@@ -116,7 +116,8 @@ cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	itmr_nsec_cycle_ratio = itmr_freq * (1ULL << 32) / 1000000000;
 	itmr_nsec_max = UINT64_MAX / itmr_nsec_cycle_ratio;
diff --git a/sys/arch/i386/i386/lapic.c b/sys/arch/i386/i386/lapic.c
index 49d9dfcfe89..97cfb45979a 100644
--- a/sys/arch/i386/i386/lapic.c
+++ b/sys/arch/i386/i386/lapic.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: lapic.c,v 1.56 2023/08/23 01:55:46 cheloha Exp $	*/
+/*	$OpenBSD: lapic.c,v 1.57 2023/09/14 19:39:48 cheloha Exp $	*/
 /* $NetBSD: lapic.c,v 1.1.2.8 2000/02/23 06:10:50 sommerfeld Exp $ */
 
 /*-
@@ -326,7 +326,8 @@ lapic_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 }
 
 extern int gettick(void);	/* XXX put in header file */
diff --git a/sys/arch/loongson/dev/glxclk.c b/sys/arch/loongson/dev/glxclk.c
index 652462d534f..d3df7cf941c 100644
--- a/sys/arch/loongson/dev/glxclk.c
+++ b/sys/arch/loongson/dev/glxclk.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: glxclk.c,v 1.9 2023/08/26 09:37:43 visa Exp $	*/
+/*	$OpenBSD: glxclk.c,v 1.10 2023/09/14 19:39:48 cheloha Exp $	*/
 
 /*
  * Copyright (c) 2013 Paul Irofti.
@@ -189,10 +189,11 @@ glxclk_initclock(void)
 	 */
 	stathz = hz = 128;
 	profhz = hz * 10;
+	statclock_is_randomized = 1;
 	tick = 1000000 / hz;
 	tick_nsec = 1000000000 / hz;
 
-	clockintr_init(CL_RNDSTAT);
+	clockintr_init(0);
 }
 
 void
diff --git a/sys/arch/macppc/macppc/clock.c b/sys/arch/macppc/macppc/clock.c
index 93084b0573a..a9bed56a627 100644
--- a/sys/arch/macppc/macppc/clock.c
+++ b/sys/arch/macppc/macppc/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.56 2023/08/23 01:55:47 cheloha Exp $	*/
+/*	$OpenBSD: clock.c,v 1.57 2023/09/14 19:39:48 cheloha Exp $	*/
 /*	$NetBSD: clock.c,v 1.1 1996/09/30 16:34:40 ws Exp $	*/
 
 /*
@@ -195,7 +195,8 @@ cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	dec_nsec_cycle_ratio = ticks_per_sec * (1ULL << 32) / 1000000000;
 	dec_nsec_max = UINT64_MAX / dec_nsec_cycle_ratio;
diff --git a/sys/arch/mips64/mips64/clock.c b/sys/arch/mips64/mips64/clock.c
index afcf68c509b..0afc2e7c73d 100644
--- a/sys/arch/mips64/mips64/clock.c
+++ b/sys/arch/mips64/mips64/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.51 2023/08/23 01:55:47 cheloha Exp $ */
+/*	$OpenBSD: clock.c,v 1.52 2023/09/14 19:39:48 cheloha Exp $ */
 
 /*
  * Copyright (c) 2001-2004 Opsycon AB  (www.opsycon.se / www.opsycon.com)
@@ -241,7 +241,8 @@ cp0_initclock(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 }
 
 /*
diff --git a/sys/arch/powerpc64/powerpc64/clock.c b/sys/arch/powerpc64/powerpc64/clock.c
index 39cab54e93c..7de2ac52c2e 100644
--- a/sys/arch/powerpc64/powerpc64/clock.c
+++ b/sys/arch/powerpc64/powerpc64/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.12 2023/08/23 01:55:47 cheloha Exp $	*/
+/*	$OpenBSD: clock.c,v 1.13 2023/09/14 19:39:48 cheloha Exp $	*/
 
 /*
  * Copyright (c) 2020 Mark Kettenis <kettenis@openbsd.org>
@@ -94,7 +94,8 @@ cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	evcount_attach(&clock_count, "clock", NULL);
 }
diff --git a/sys/arch/riscv64/riscv64/clock.c b/sys/arch/riscv64/riscv64/clock.c
index cd8c8ec6da6..5685e9c4d85 100644
--- a/sys/arch/riscv64/riscv64/clock.c
+++ b/sys/arch/riscv64/riscv64/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.11 2023/08/23 01:55:47 cheloha Exp $	*/
+/*	$OpenBSD: clock.c,v 1.12 2023/09/14 19:39:48 cheloha Exp $	*/
 
 /*
  * Copyright (c) 2020 Mark Kettenis <kettenis@openbsd.org>
@@ -92,7 +92,8 @@ cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	riscv_intc_intr_establish(IRQ_TIMER_SUPERVISOR, 0,
 	    clock_intr, NULL, NULL);
diff --git a/sys/arch/sparc64/sparc64/clock.c b/sys/arch/sparc64/sparc64/clock.c
index 9255d571a2e..84ec8404d6e 100644
--- a/sys/arch/sparc64/sparc64/clock.c
+++ b/sys/arch/sparc64/sparc64/clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: clock.c,v 1.80 2023/08/23 01:55:47 cheloha Exp $	*/
+/*	$OpenBSD: clock.c,v 1.81 2023/09/14 19:39:48 cheloha Exp $	*/
 /*	$NetBSD: clock.c,v 1.41 2001/07/24 19:29:25 eeh Exp $ */
 
 /*
@@ -501,7 +501,8 @@ cpu_initclocks(void)
 
 	stathz = hz;
 	profhz = stathz * 10;
-	clockintr_init(CL_RNDSTAT);
+	statclock_is_randomized = 1;
+	clockintr_init(0);
 
 	/* Make sure we have a sane cpu_clockrate -- we'll need it */
 	if (!cpu_clockrate) 
diff --git a/sys/kern/kern_clock.c b/sys/kern/kern_clock.c
index 1c8da764a31..e23ab3e9833 100644
--- a/sys/kern/kern_clock.c
+++ b/sys/kern/kern_clock.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_clock.c,v 1.116 2023/09/09 18:19:03 cheloha Exp $	*/
+/*	$OpenBSD: kern_clock.c,v 1.117 2023/09/14 19:39:47 cheloha Exp $	*/
 /*	$NetBSD: kern_clock.c,v 1.34 1996/06/09 04:51:03 briggs Exp $	*/
 
 /*-
@@ -86,6 +86,8 @@ int	ticks = INT_MAX - (15 * 60 * HZ);
 /* Don't force early wrap around, triggers bug in inteldrm */
 volatile unsigned long jiffies;
 
+int statclock_is_randomized;	/* [I] fixed or pseudorandom period? */
+
 /*
  * Initialize clock frequencies and start both clocks running.
  */
diff --git a/sys/kern/kern_clockintr.c b/sys/kern/kern_clockintr.c
index aeeb7ed9158..ad92d10cddf 100644
--- a/sys/kern/kern_clockintr.c
+++ b/sys/kern/kern_clockintr.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: kern_clockintr.c,v 1.47 2023/09/10 03:08:05 cheloha Exp $ */
+/* $OpenBSD: kern_clockintr.c,v 1.48 2023/09/14 19:39:47 cheloha Exp $ */
 /*
  * Copyright (c) 2003 Dale Rahn <drahn@openbsd.org>
  * Copyright (c) 2020 Mark Kettenis <kettenis@openbsd.org>
@@ -169,7 +169,7 @@ clockintr_cpu_init(const struct intrclock *ic)
 	 * We can always advance the statclock.  There is no reason to
 	 * stagger a randomized statclock.
 	 */
-	if (!ISSET(clockintr_flags, CL_RNDSTAT)) {
+	if (!statclock_is_randomized) {
 		if (cq->cq_statclock->cl_expiration == 0) {
 			clockintr_stagger(cq->cq_statclock, statclock_avg,
 			    multiplier, MAXCPUS);
@@ -475,7 +475,7 @@ clockintr_statclock(struct clockintr *cl, void *frame, void *arg)
 {
 	uint64_t count, i;
 
-	if (ISSET(clockintr_flags, CL_RNDSTAT)) {
+	if (statclock_is_randomized) {
 		count = clockintr_advance_random(cl, statclock_min,
 		    statclock_mask);
 	} else {
diff --git a/sys/sys/clockintr.h b/sys/sys/clockintr.h
index b4dceefa59a..3de42b6d436 100644
--- a/sys/sys/clockintr.h
+++ b/sys/sys/clockintr.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: clockintr.h,v 1.13 2023/09/10 03:08:05 cheloha Exp $ */
+/* $OpenBSD: clockintr.h,v 1.14 2023/09/14 19:39:47 cheloha Exp $ */
 /*
  * Copyright (c) 2020-2022 Scott Cheloha <cheloha@openbsd.org>
  *
@@ -115,8 +115,7 @@ struct clockintr_queue {
 #define CL_STATE_MASK		0x00000001
 
 /* Global behavior flags. */
-#define CL_RNDSTAT		0x80000000	/* randomized statclock */
-#define CL_FLAG_MASK		0x80000000
+#define CL_FLAG_MASK		0x00000000
 
 void clockintr_cpu_init(const struct intrclock *);
 int clockintr_dispatch(void *);
diff --git a/sys/sys/systm.h b/sys/sys/systm.h
index 9a095f7d255..6d8a65bdb77 100644
--- a/sys/sys/systm.h
+++ b/sys/sys/systm.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: systm.h,v 1.165 2023/08/23 01:55:45 cheloha Exp $	*/
+/*	$OpenBSD: systm.h,v 1.166 2023/09/14 19:39:47 cheloha Exp $	*/
 /*	$NetBSD: systm.h,v 1.50 1996/06/09 04:55:09 briggs Exp $	*/
 
 /*-
@@ -234,6 +234,7 @@ int	tstohz(const struct timespec *);
 void	realitexpire(void *);
 
 extern uint32_t hardclock_period;
+extern int statclock_is_randomized;
 
 struct clockframe;
 void	hardclock(struct clockframe *);