svn commit: r202387 - in head/sys: amd64/amd64 amd64/include
amd64/isa conf i386/i386 i386/include i386/isa pc98/cbus
Attilio Rao
attilio at FreeBSD.org
Fri Jan 15 16:04:30 UTC 2010
Author: attilio
Date: Fri Jan 15 16:04:30 2010
New Revision: 202387
URL: http://svn.freebsd.org/changeset/base/202387
Log:
Handling all the three clocks (hardclock, softclock, profclock) with the
LAPIC may lead to aliasing for softclock and profclock because frequencies
are sized in order to fit mainly hardclock.
atrtc used to take care of the softclock and profclock and it does still
do, if the LAPIC can't handle the clocks properly.
Revert the change when the LAPIC started taking charge of all three of
them and let atrtc handle softclock and profclock if not explicitly
requested. Such request can be made setting != 0 the new tunable
machdep.lapic_allclocks or if the new device ATPIC is not present
within the i386 kernel config (atrtc is linked to atpic presence).
Diagnosed by: Sandvine Incorporated
Reviewed by: jhb, emaste
Sponsored by: Sandvine Incorporated
MFC: 3 weeks
Modified:
head/sys/amd64/amd64/local_apic.c
head/sys/amd64/include/apicvar.h
head/sys/amd64/isa/clock.c
head/sys/conf/options.i386
head/sys/i386/i386/local_apic.c
head/sys/i386/include/apicvar.h
head/sys/i386/isa/clock.c
head/sys/pc98/cbus/clock.c
Modified: head/sys/amd64/amd64/local_apic.c
==============================================================================
--- head/sys/amd64/amd64/local_apic.c Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/amd64/amd64/local_apic.c Fri Jan 15 16:04:30 2010 (r202387)
@@ -160,6 +160,9 @@ static uint32_t lvt_mode(struct lapic *l
struct pic lapic_pic = { .pic_resume = lapic_resume };
+static int lapic_allclocks;
+TUNABLE_INT("machdep.lapic_allclocks", &lapic_allclocks);
+
static uint32_t
lvt_mode(struct lapic *la, u_int pin, uint32_t value)
{
@@ -415,10 +418,11 @@ lapic_disable_pmc(void)
/*
* Called by cpu_initclocks() on the BSP to setup the local APIC timer so
* that it can drive hardclock, statclock, and profclock. This function
- * returns true if it is able to use the local APIC timer to drive the
- * clocks and false if it is not able.
+ * returns a positive integer if it is convenient to use the local APIC
+ * for all the clocks, a negative integer if it is convenient to use the
+ * local APIC only for the hardclock and 0 if none of them can be handled.
*/
-int
+enum lapic_clock
lapic_setup_clock(void)
{
u_long value;
@@ -426,10 +430,10 @@ lapic_setup_clock(void)
/* Can't drive the timer without a local APIC. */
if (lapic == NULL)
- return (0);
+ return (LAPIC_CLOCK_NONE);
if (resource_int_value("apic", 0, "clock", &i) == 0 && i == 0)
- return (0);
+ return (LAPIC_CLOCK_NONE);
/* Start off with a divisor of 2 (power on reset default). */
lapic_timer_divisor = 2;
@@ -461,19 +465,27 @@ lapic_setup_clock(void)
* (and profhz) run at hz. If 'hz' is below 1500 but above
* 750, then we let the lapic timer run at 2 * 'hz'. If 'hz'
* is below 750 then we let the lapic timer run at 4 * 'hz'.
+ *
+ * Please note that stathz and profhz are set only if all the
+ * clocks are handled through the local APIC.
*/
- if (hz >= 1500)
+ if (lapic_allclocks != 0) {
+ if (hz >= 1500)
+ lapic_timer_hz = hz;
+ else if (hz >= 750)
+ lapic_timer_hz = hz * 2;
+ else
+ lapic_timer_hz = hz * 4;
+ } else
lapic_timer_hz = hz;
- else if (hz >= 750)
- lapic_timer_hz = hz * 2;
- else
- lapic_timer_hz = hz * 4;
- if (lapic_timer_hz < 128)
- stathz = lapic_timer_hz;
- else
- stathz = lapic_timer_hz / (lapic_timer_hz / 128);
- profhz = lapic_timer_hz;
lapic_timer_period = value / lapic_timer_hz;
+ if (lapic_allclocks != 0) {
+ if (lapic_timer_hz < 128)
+ stathz = lapic_timer_hz;
+ else
+ stathz = lapic_timer_hz / (lapic_timer_hz / 128);
+ profhz = lapic_timer_hz;
+ }
/*
* Start up the timer on the BSP. The APs will kick off their
@@ -481,7 +493,7 @@ lapic_setup_clock(void)
*/
lapic_timer_periodic(lapic_timer_period);
lapic_timer_enable_intr();
- return (1);
+ return (lapic_allclocks == 0 ? LAPIC_CLOCK_HARDCLOCK : LAPIC_CLOCK_ALL);
}
void
@@ -784,20 +796,23 @@ lapic_handle_timer(struct trapframe *fra
else
hardclock_cpu(TRAPF_USERMODE(frame));
}
+ if (lapic_allclocks != 0) {
- /* Fire statclock at stathz. */
- la->la_stat_ticks += stathz;
- if (la->la_stat_ticks >= lapic_timer_hz) {
- la->la_stat_ticks -= lapic_timer_hz;
- statclock(TRAPF_USERMODE(frame));
- }
+ /* Fire statclock at stathz. */
+ la->la_stat_ticks += stathz;
+ if (la->la_stat_ticks >= lapic_timer_hz) {
+ la->la_stat_ticks -= lapic_timer_hz;
+ statclock(TRAPF_USERMODE(frame));
+ }
- /* Fire profclock at profhz, but only when needed. */
- la->la_prof_ticks += profhz;
- if (la->la_prof_ticks >= lapic_timer_hz) {
- la->la_prof_ticks -= lapic_timer_hz;
- if (profprocs != 0)
- profclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
+ /* Fire profclock at profhz, but only when needed. */
+ la->la_prof_ticks += profhz;
+ if (la->la_prof_ticks >= lapic_timer_hz) {
+ la->la_prof_ticks -= lapic_timer_hz;
+ if (profprocs != 0)
+ profclock(TRAPF_USERMODE(frame),
+ TRAPF_PC(frame));
+ }
}
critical_exit();
}
Modified: head/sys/amd64/include/apicvar.h
==============================================================================
--- head/sys/amd64/include/apicvar.h Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/amd64/include/apicvar.h Fri Jan 15 16:04:30 2010 (r202387)
@@ -157,6 +157,12 @@
#define APIC_BUS_PCI 2
#define APIC_BUS_MAX APIC_BUS_PCI
+enum lapic_clock {
+ LAPIC_CLOCK_NONE,
+ LAPIC_CLOCK_HARDCLOCK,
+ LAPIC_CLOCK_ALL
+};
+
/*
* An APIC enumerator is a psuedo bus driver that enumerates APIC's including
* CPU's and I/O APIC's.
@@ -224,7 +230,7 @@ int lapic_set_lvt_triggermode(u_int apic
enum intr_trigger trigger);
void lapic_set_tpr(u_int vector);
void lapic_setup(int boot);
-int lapic_setup_clock(void);
+enum lapic_clock lapic_setup_clock(void);
#endif /* !LOCORE */
#endif /* _MACHINE_APICVAR_H_ */
Modified: head/sys/amd64/isa/clock.c
==============================================================================
--- head/sys/amd64/isa/clock.c Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/amd64/isa/clock.c Fri Jan 15 16:04:30 2010 (r202387)
@@ -91,7 +91,7 @@ static u_int32_t i8254_offset;
static int (*i8254_pending)(struct intsrc *);
static int i8254_ticked;
static int using_atrtc_timer;
-static int using_lapic_timer;
+static enum lapic_clock using_lapic_timer = LAPIC_CLOCK_NONE;
/* Values for timerX_state: */
#define RELEASED 0
@@ -160,7 +160,8 @@ clkintr(struct trapframe *frame)
clkintr_pending = 0;
mtx_unlock_spin(&clock_lock);
}
- KASSERT(!using_lapic_timer, ("clk interrupt enabled with lapic timer"));
+ KASSERT(using_lapic_timer == LAPIC_CLOCK_NONE,
+ ("clk interrupt enabled with lapic timer"));
if (using_atrtc_timer) {
#ifdef SMP
@@ -422,7 +423,7 @@ set_i8254_freq(u_int freq, int intr_freq
i8254_timecounter.tc_frequency = freq;
mtx_lock_spin(&clock_lock);
i8254_freq = freq;
- if (using_lapic_timer)
+ if (using_lapic_timer != LAPIC_CLOCK_NONE)
new_i8254_real_max_count = 0x10000;
else
new_i8254_real_max_count = TIMER_DIV(intr_freq);
@@ -485,7 +486,7 @@ cpu_initclocks()
* that it can drive hardclock(). Otherwise, change the 8254
* timecounter to user a simpler algorithm.
*/
- if (!using_lapic_timer) {
+ if (using_lapic_timer == LAPIC_CLOCK_NONE) {
intr_add_handler("clk", 0, (driver_filter_t *)clkintr, NULL,
NULL, INTR_TYPE_CLK, NULL);
i8254_intsrc = intr_lookup_source(0);
@@ -508,7 +509,7 @@ cpu_initclocks()
* kernel clocks, then setup the RTC to periodically interrupt to
* drive statclock() and profclock().
*/
- if (!using_lapic_timer) {
+ if (using_lapic_timer != LAPIC_CLOCK_ALL) {
using_atrtc_timer = atrtc_setup_clock();
if (using_atrtc_timer) {
/* Enable periodic interrupts from the RTC. */
@@ -532,7 +533,7 @@ void
cpu_startprofclock(void)
{
- if (using_lapic_timer || !using_atrtc_timer)
+ if (using_lapic_timer == LAPIC_CLOCK_ALL || !using_atrtc_timer)
return;
atrtc_rate(RTCSA_PROF);
psdiv = pscnt = psratio;
@@ -542,7 +543,7 @@ void
cpu_stopprofclock(void)
{
- if (using_lapic_timer || !using_atrtc_timer)
+ if (using_lapic_timer == LAPIC_CLOCK_ALL || !using_atrtc_timer)
return;
atrtc_rate(RTCSA_NOPROF);
psdiv = pscnt = 1;
Modified: head/sys/conf/options.i386
==============================================================================
--- head/sys/conf/options.i386 Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/conf/options.i386 Fri Jan 15 16:04:30 2010 (r202387)
@@ -105,6 +105,7 @@ NETGRAPH_CRONYX opt_ng_cronyx.h
# Device options
DEV_APIC opt_apic.h
+DEV_ATPIC opt_atpic.h
DEV_NPX opt_npx.h
ASR_COMPAT opt_asr.h
Modified: head/sys/i386/i386/local_apic.c
==============================================================================
--- head/sys/i386/i386/local_apic.c Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/i386/i386/local_apic.c Fri Jan 15 16:04:30 2010 (r202387)
@@ -34,6 +34,7 @@
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
+#include "opt_atpic.h"
#include "opt_hwpmc_hooks.h"
#include "opt_kdtrace.h"
@@ -160,6 +161,17 @@ static uint32_t lvt_mode(struct lapic *l
struct pic lapic_pic = { .pic_resume = lapic_resume };
+/*
+ * The atrtc device is compiled in only if atpic is present.
+ * If it is not, force lapic to take care of all the clocks.
+ */
+#ifdef DEV_ATPIC
+static int lapic_allclocks;
+TUNABLE_INT("machdep.lapic_allclocks", &lapic_allclocks);
+#else
+static int lapic_allclocks = 1;
+#endif
+
static uint32_t
lvt_mode(struct lapic *la, u_int pin, uint32_t value)
{
@@ -416,11 +428,9 @@ lapic_disable_pmc(void)
/*
* Called by cpu_initclocks() on the BSP to setup the local APIC timer so
- * that it can drive hardclock, statclock, and profclock. This function
- * returns true if it is able to use the local APIC timer to drive the
- * clocks and false if it is not able.
+ * that it can drive hardclock, statclock, and profclock.
*/
-int
+enum lapic_clock
lapic_setup_clock(void)
{
u_long value;
@@ -428,10 +438,10 @@ lapic_setup_clock(void)
/* Can't drive the timer without a local APIC. */
if (lapic == NULL)
- return (0);
+ return (LAPIC_CLOCK_NONE);
if (resource_int_value("apic", 0, "clock", &i) == 0 && i == 0)
- return (0);
+ return (LAPIC_CLOCK_NONE);
/* Start off with a divisor of 2 (power on reset default). */
lapic_timer_divisor = 2;
@@ -463,19 +473,27 @@ lapic_setup_clock(void)
* (and profhz) run at hz. If 'hz' is below 1500 but above
* 750, then we let the lapic timer run at 2 * 'hz'. If 'hz'
* is below 750 then we let the lapic timer run at 4 * 'hz'.
+ *
+ * Please note that stathz and profhz are set only if all the
+ * clocks are handled through the local APIC.
*/
- if (hz >= 1500)
+ if (lapic_allclocks != 0) {
+ if (hz >= 1500)
+ lapic_timer_hz = hz;
+ else if (hz >= 750)
+ lapic_timer_hz = hz * 2;
+ else
+ lapic_timer_hz = hz * 4;
+ } else
lapic_timer_hz = hz;
- else if (hz >= 750)
- lapic_timer_hz = hz * 2;
- else
- lapic_timer_hz = hz * 4;
- if (lapic_timer_hz < 128)
- stathz = lapic_timer_hz;
- else
- stathz = lapic_timer_hz / (lapic_timer_hz / 128);
- profhz = lapic_timer_hz;
lapic_timer_period = value / lapic_timer_hz;
+ if (lapic_allclocks != 0) {
+ if (lapic_timer_hz < 128)
+ stathz = lapic_timer_hz;
+ else
+ stathz = lapic_timer_hz / (lapic_timer_hz / 128);
+ profhz = lapic_timer_hz;
+ }
/*
* Start up the timer on the BSP. The APs will kick off their
@@ -483,7 +501,7 @@ lapic_setup_clock(void)
*/
lapic_timer_periodic(lapic_timer_period);
lapic_timer_enable_intr();
- return (1);
+ return (lapic_allclocks == 0 ? LAPIC_CLOCK_HARDCLOCK : LAPIC_CLOCK_ALL);
}
void
@@ -786,20 +804,23 @@ lapic_handle_timer(struct trapframe *fra
else
hardclock_cpu(TRAPF_USERMODE(frame));
}
+ if (lapic_allclocks != 0) {
- /* Fire statclock at stathz. */
- la->la_stat_ticks += stathz;
- if (la->la_stat_ticks >= lapic_timer_hz) {
- la->la_stat_ticks -= lapic_timer_hz;
- statclock(TRAPF_USERMODE(frame));
- }
+ /* Fire statclock at stathz. */
+ la->la_stat_ticks += stathz;
+ if (la->la_stat_ticks >= lapic_timer_hz) {
+ la->la_stat_ticks -= lapic_timer_hz;
+ statclock(TRAPF_USERMODE(frame));
+ }
- /* Fire profclock at profhz, but only when needed. */
- la->la_prof_ticks += profhz;
- if (la->la_prof_ticks >= lapic_timer_hz) {
- la->la_prof_ticks -= lapic_timer_hz;
- if (profprocs != 0)
- profclock(TRAPF_USERMODE(frame), TRAPF_PC(frame));
+ /* Fire profclock at profhz, but only when needed. */
+ la->la_prof_ticks += profhz;
+ if (la->la_prof_ticks >= lapic_timer_hz) {
+ la->la_prof_ticks -= lapic_timer_hz;
+ if (profprocs != 0)
+ profclock(TRAPF_USERMODE(frame),
+ TRAPF_PC(frame));
+ }
}
critical_exit();
}
Modified: head/sys/i386/include/apicvar.h
==============================================================================
--- head/sys/i386/include/apicvar.h Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/i386/include/apicvar.h Fri Jan 15 16:04:30 2010 (r202387)
@@ -186,6 +186,12 @@
#define APIC_BUS_PCI 2
#define APIC_BUS_MAX APIC_BUS_PCI
+enum lapic_clock {
+ LAPIC_CLOCK_NONE,
+ LAPIC_CLOCK_HARDCLOCK,
+ LAPIC_CLOCK_ALL
+};
+
/*
* An APIC enumerator is a psuedo bus driver that enumerates APIC's including
* CPU's and I/O APIC's.
@@ -253,7 +259,7 @@ int lapic_set_lvt_triggermode(u_int apic
enum intr_trigger trigger);
void lapic_set_tpr(u_int vector);
void lapic_setup(int boot);
-int lapic_setup_clock(void);
+enum lapic_clock lapic_setup_clock(void);
#endif /* !LOCORE */
#endif /* _MACHINE_APICVAR_H_ */
Modified: head/sys/i386/isa/clock.c
==============================================================================
--- head/sys/i386/isa/clock.c Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/i386/isa/clock.c Fri Jan 15 16:04:30 2010 (r202387)
@@ -106,7 +106,7 @@ static u_int32_t i8254_offset;
static int (*i8254_pending)(struct intsrc *);
static int i8254_ticked;
static int using_atrtc_timer;
-static int using_lapic_timer;
+static enum lapic_clock using_lapic_timer = LAPIC_CLOCK_NONE;
/* Values for timerX_state: */
#define RELEASED 0
@@ -175,7 +175,8 @@ clkintr(struct trapframe *frame)
clkintr_pending = 0;
mtx_unlock_spin(&clock_lock);
}
- KASSERT(!using_lapic_timer, ("clk interrupt enabled with lapic timer"));
+ KASSERT(using_lapic_timer == LAPIC_CLOCK_NONE,
+ ("clk interrupt enabled with lapic timer"));
#ifdef KDTRACE_HOOKS
/*
@@ -453,7 +454,7 @@ set_i8254_freq(u_int freq, int intr_freq
i8254_timecounter.tc_frequency = freq;
mtx_lock_spin(&clock_lock);
i8254_freq = freq;
- if (using_lapic_timer)
+ if (using_lapic_timer != LAPIC_CLOCK_NONE)
new_i8254_real_max_count = 0x10000;
else
new_i8254_real_max_count = TIMER_DIV(intr_freq);
@@ -533,7 +534,7 @@ cpu_initclocks()
* that it can drive hardclock(). Otherwise, change the 8254
* timecounter to user a simpler algorithm.
*/
- if (!using_lapic_timer) {
+ if (using_lapic_timer == LAPIC_CLOCK_NONE) {
intr_add_handler("clk", 0, (driver_filter_t *)clkintr, NULL,
NULL, INTR_TYPE_CLK, NULL);
i8254_intsrc = intr_lookup_source(0);
@@ -556,7 +557,7 @@ cpu_initclocks()
* kernel clocks, then setup the RTC to periodically interrupt to
* drive statclock() and profclock().
*/
- if (!using_lapic_timer) {
+ if (using_lapic_timer != LAPIC_CLOCK_ALL) {
using_atrtc_timer = atrtc_setup_clock();
if (using_atrtc_timer) {
/* Enable periodic interrupts from the RTC. */
@@ -580,7 +581,7 @@ void
cpu_startprofclock(void)
{
- if (using_lapic_timer || !using_atrtc_timer)
+ if (using_lapic_timer == LAPIC_CLOCK_ALL || !using_atrtc_timer)
return;
atrtc_rate(RTCSA_PROF);
psdiv = pscnt = psratio;
@@ -590,7 +591,7 @@ void
cpu_stopprofclock(void)
{
- if (using_lapic_timer || !using_atrtc_timer)
+ if (using_lapic_timer == LAPIC_CLOCK_ALL || !using_atrtc_timer)
return;
atrtc_rate(RTCSA_NOPROF);
psdiv = pscnt = 1;
Modified: head/sys/pc98/cbus/clock.c
==============================================================================
--- head/sys/pc98/cbus/clock.c Fri Jan 15 16:01:22 2010 (r202386)
+++ head/sys/pc98/cbus/clock.c Fri Jan 15 16:04:30 2010 (r202387)
@@ -101,7 +101,7 @@ static u_int32_t i8254_lastcount;
static u_int32_t i8254_offset;
static int (*i8254_pending)(struct intsrc *);
static int i8254_ticked;
-static int using_lapic_timer;
+static enum lapic_clock using_lapic_timer = LAPIC_CLOCK_NONE;
/* Values for timerX_state: */
#define RELEASED 0
@@ -164,7 +164,8 @@ clkintr(struct trapframe *frame)
clkintr_pending = 0;
mtx_unlock_spin(&clock_lock);
}
- KASSERT(!using_lapic_timer, ("clk interrupt enabled with lapic timer"));
+ KASSERT(using_lapic_timer == LAPIC_CLOCK_NONE,
+ ("clk interrupt enabled with lapic timer"));
#ifdef KDTRACE_HOOKS
/*
@@ -360,7 +361,7 @@ set_i8254_freq(u_int freq, int intr_freq
i8254_timecounter.tc_frequency = freq;
mtx_lock_spin(&clock_lock);
i8254_freq = freq;
- if (using_lapic_timer)
+ if (using_lapic_timer != LAPIC_CLOCK_NONE)
new_i8254_real_max_count = 0x10000;
else
new_i8254_real_max_count = TIMER_DIV(intr_freq);
@@ -443,7 +444,7 @@ cpu_initclocks()
* that it can drive hardclock(). Otherwise, change the 8254
* timecounter to user a simpler algorithm.
*/
- if (!using_lapic_timer) {
+ if (using_lapic_timer == LAPIC_CLOCK_NONE) {
intr_add_handler("clk", 0, (driver_filter_t *)clkintr, NULL,
NULL, INTR_TYPE_CLK, NULL);
i8254_intsrc = intr_lookup_source(0);
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