[PATCH] New x86_64 time code for 2.5.70

Bryan O'Sullivan (bos@serpentine.com)
11 Jun 2003 11:50:32 -0700


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The time code for x86-64 in 2.5.70 isout of date and wildly unstable,
setting the clock to the year 1,115,117 (!) during boot about 60% of the
time. This subsequently causes other pieces of completely unrelated
userspace software to crash randomly for no obvious reason once the
system comes up.

I've forward-ported Vojtech's time code from 2.4, fixing some locking
along the way. The new code supports using the AMD8111 HPET for time
calculations. It also works stably with the PIT/TSC on every boot,
which is the source of the time problems in current 2.5.

Right now, the only known problem is with the fixup of jiffies if a
timer interrupt is lost, which I've hence turned off. There's
preliminary support for using HPET for the gettimeofday vsyscall, but
since vsyscalls are disabled on x86-64 for now, that's obviously
untested.

<b

arch/x86_64/Kconfig | 12 +
arch/x86_64/kernel/acpi/boot.c | 6
arch/x86_64/kernel/apic.c | 8 +
arch/x86_64/kernel/smpboot.c | 11 +
arch/x86_64/kernel/time.c | 253 ++++++++++++++++++++++++++++++++++----- arch/x86_64/kernel/vsyscall.c | 16 +-
arch/x86_64/vmlinux.lds.S | 6
include/asm-x86_64/fixmap.h | 2
include/asm-x86_64/mc146818rtc.h | 5
include/asm-x86_64/timex.h | 30 ++++
include/asm-x86_64/vsyscall.h | 18 +-
11 files changed, 315 insertions(+), 52 deletions(-)

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--- linux-2.5/arch/x86_64/vmlinux.lds.S 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/vmlinux.lds.S 2003-06-10 10:49:42.000000000 -0700
@@ -50,10 +50,10 @@
.xtime_lock : AT ((LOADADDR(.vsyscall_0) + SIZEOF(.vsyscall_0) + 63) & ~(63)) { *(.xtime_lock) }
xtime_lock = LOADADDR(.xtime_lock);
. = ALIGN(16);
- .hpet : AT ((LOADADDR(.xtime_lock) + SIZEOF(.xtime_lock) + 15) & ~(15)) { *(.hpet) }
- hpet = LOADADDR(.hpet);
+ .vxtime : AT ((LOADADDR(.xtime_lock) + SIZEOF(.xtime_lock) + 15) & ~(15)) { *(.vxtime) }
+ vxtime = LOADADDR(.vxtime);
. = ALIGN(16);
- .wall_jiffies : AT ((LOADADDR(.hpet) + SIZEOF(.hpet) + 15) & ~(15)) { *(.wall_jiffies) }
+ .wall_jiffies : AT ((LOADADDR(.vxtime) + SIZEOF(.vxtime) + 15) & ~(15)) { *(.wall_jiffies) }
wall_jiffies = LOADADDR(.wall_jiffies);
. = ALIGN(16);
.sys_tz : AT ((LOADADDR(.wall_jiffies) + SIZEOF(.wall_jiffies) + 15) & ~(15)) { *(.sys_tz) }
--- linux-2.5/arch/x86_64/kernel/apic.c 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/kernel/apic.c 2003-06-11 10:26:47.000000000 -0700
@@ -690,7 +690,13 @@
}

/* wait for irq slice */
- {
+ if (vxtime.hpet_address) {
+ int trigger = hpet_readl(HPET_T0_CMP);
+ while (hpet_readl(HPET_COUNTER) >= trigger)
+ /* do nothing */ ;
+ while (hpet_readl(HPET_COUNTER) < trigger)
+ /* do nothing */ ;
+ } else {
int c1, c2;
outb_p(0x00, 0x43);
c2 = inb_p(0x40);
--- linux-2.5/include/asm-x86_64/fixmap.h 2003-06-11 11:43:32.000000000 -0700
+++ x86-64-2.5/include/asm-x86_64/fixmap.h 2003-06-09 15:50:07.000000000 -0700
@@ -35,6 +35,8 @@
enum fixed_addresses {
VSYSCALL_LAST_PAGE,
VSYSCALL_FIRST_PAGE = VSYSCALL_LAST_PAGE + ((VSYSCALL_END-VSYSCALL_START) >> PAGE_SHIFT) - 1,
+ VSYSCALL_HPET,
+ FIX_HPET_BASE,
#ifdef CONFIG_X86_LOCAL_APIC
FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */
#endif
--- linux-2.5/arch/x86_64/kernel/acpi/boot.c 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/kernel/acpi/boot.c 2003-06-10 10:36:47.000000000 -0700
@@ -244,9 +244,11 @@
return -1;
}

- hpet.address = hpet_tbl->addr.addrl | ((long) hpet_tbl->addr.addrh << 32);
+ vxtime.hpet_address = hpet_tbl->addr.addrl |
+ ((long) hpet_tbl->addr.addrh << 32);

- printk(KERN_INFO "acpi: HPET id: %#x base: %#lx\n", hpet_tbl->id, hpet.address);
+ printk(KERN_INFO "acpi: HPET id: %#x base: %#lx\n",
+ hpet_tbl->id, vxtime.hpet_address);

return 0;
}
--- linux-2.5/include/asm-x86_64/mc146818rtc.h 2003-06-11 11:43:32.000000000 -0700
+++ x86-64-2.5/include/asm-x86_64/mc146818rtc.h 2003-06-09 15:50:45.000000000 -0700
@@ -24,6 +24,11 @@
outb_p((val),RTC_PORT(1)); \
})

+#ifndef CONFIG_HPET_TIMER
#define RTC_IRQ 8
+#else
+/* Temporary workaround due to IRQ routing problem. */
+#define RTC_IRQ 0
+#endif

#endif /* _ASM_MC146818RTC_H */
--- linux-2.5/include/asm-x86_64/timex.h 2003-06-11 11:43:32.000000000 -0700
+++ x86-64-2.5/include/asm-x86_64/timex.h 2003-06-10 10:48:06.000000000 -0700
@@ -30,6 +30,34 @@

extern unsigned int cpu_khz;

-extern struct hpet_data hpet;
+/*
+ * Documentation on HPET can be found at:
+ * http://www.intel.com/ial/home/sp/pcmmspec.htm
+ * ftp://download.intel.com/ial/home/sp/mmts098.pdf
+ */
+
+#define HPET_ID 0x000
+#define HPET_PERIOD 0x004
+#define HPET_CFG 0x010
+#define HPET_STATUS 0x020
+#define HPET_COUNTER 0x0f0
+#define HPET_T0_CFG 0x100
+#define HPET_T0_CMP 0x108
+#define HPET_T0_ROUTE 0x110
+
+#define HPET_ID_VENDOR 0xffff0000
+#define HPET_ID_LEGSUP 0x00008000
+#define HPET_ID_NUMBER 0x00000f00
+#define HPET_ID_REV 0x000000ff
+
+#define HPET_CFG_ENABLE 0x001
+#define HPET_CFG_LEGACY 0x002
+
+#define HPET_T0_ENABLE 0x004
+#define HPET_T0_PERIODIC 0x008
+#define HPET_T0_SETVAL 0x040
+#define HPET_T0_32BIT 0x100
+
+extern struct vxtime_data vxtime;

#endif
--- linux-2.5/arch/x86_64/kernel/time.c 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/kernel/time.c 2003-06-11 10:20:49.000000000 -0700
@@ -24,6 +24,7 @@
#include <linux/module.h>
#include <linux/device.h>
#include <linux/bcd.h>
+#include <asm/pgtable.h>
#include <asm/vsyscall.h>
#include <asm/timex.h>
#ifdef CONFIG_X86_LOCAL_APIC
@@ -35,41 +36,59 @@
extern int using_apic_timer;

spinlock_t rtc_lock = SPIN_LOCK_UNLOCKED;
+spinlock_t i8253_lock = SPIN_LOCK_UNLOCKED;

extern int using_apic_timer;
extern void smp_local_timer_interrupt(struct pt_regs * regs);

+#undef HPET_HACK_ENABLE_DANGEROUS
+

unsigned int cpu_khz; /* TSC clocks / usec, not used here */
unsigned long hpet_period; /* fsecs / HPET clock */
unsigned long hpet_tick; /* HPET clocks / interrupt */
-int hpet_report_lost_ticks; /* command line option */
+unsigned long vxtime_hz = 1193182;
+int report_lost_ticks; /* command line option */

-struct hpet_data __hpet __section_hpet; /* address, quotient, trigger, hz */
+struct vxtime_data __vxtime __section_vxtime; /* for vsyscalls */

volatile unsigned long __jiffies __section_jiffies = INITIAL_JIFFIES;
unsigned long __wall_jiffies __section_wall_jiffies = INITIAL_JIFFIES;
struct timespec __xtime __section_xtime;
struct timezone __sys_tz __section_sys_tz;

+static inline void rdtscll_sync(unsigned long *tsc)
+{
+ sync_core();
+ rdtscll(*tsc);
+}
+
/*
* do_gettimeoffset() returns microseconds since last timer interrupt was
* triggered by hardware. A memory read of HPET is slower than a register read
* of TSC, but much more reliable. It's also synchronized to the timer
* interrupt. Note that do_gettimeoffset() may return more than hpet_tick, if a
- * timer interrupt has happened already, but hpet.trigger wasn't updated yet.
+ * timer interrupt has happened already, but vxtime.trigger wasn't updated yet.
* This is not a problem, because jiffies hasn't updated either. They are bound
* together by xtime_lock.
*/

-inline unsigned int do_gettimeoffset(void)
+static inline unsigned int do_gettimeoffset_tsc(void)
{
unsigned long t;
- sync_core();
- rdtscll(t);
- return (t - hpet.last_tsc) * (1000000L / HZ) / hpet.ticks + hpet.offset;
+ unsigned long x;
+ rdtscll_sync(&t);
+ x = ((t - vxtime.last_tsc) * vxtime.tsc_quot) >> 32;
+ return x;
}

+static inline unsigned int do_gettimeoffset_hpet(void)
+{
+ return ((hpet_readl(HPET_COUNTER) - vxtime.last) * vxtime.quot) >> 32;
+}
+
+unsigned int (*do_gettimeoffset)(void) = do_gettimeoffset_tsc;
+
/*
* This version of gettimeofday() has microsecond resolution and better than
* microsecond precision, as we're using at least a 10 MHz (usually 14.31818
@@ -87,7 +106,8 @@
sec = xtime.tv_sec;
usec = xtime.tv_nsec / 1000;

- t = (jiffies - wall_jiffies) * (1000000L / HZ) + do_gettimeoffset();
+ t = (jiffies - wall_jiffies) * (1000000L / HZ) +
+ do_gettimeoffset();
usec += t;

} while (read_seqretry(&xtime_lock, seq));
@@ -178,8 +198,8 @@
CMOS_WRITE(real_seconds, RTC_SECONDS);
CMOS_WRITE(real_minutes, RTC_MINUTES);
} else
- printk(KERN_WARNING "time.c: can't update CMOS clock from %d to %d\n",
- cmos_minutes, real_minutes);
+ printk(KERN_WARNING "time.c: can't update CMOS clock "
+ "from %d to %d\n", cmos_minutes, real_minutes);

/*
* The following flags have to be released exactly in this order, otherwise the
@@ -198,6 +218,9 @@
static irqreturn_t timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
static unsigned long rtc_update = 0;
+ unsigned long tsc, lost = 0;
+ int delay, offset = 0;
+ static unsigned long call;

/*
* Here we are in the timer irq handler. We have irqs locally disabled (so we
@@ -208,17 +231,53 @@

write_seqlock(&xtime_lock);

- {
- unsigned long t;
+ if (vxtime.hpet_address) {
+ offset = hpet_readl(HPET_T0_CMP) - hpet_tick;
+ delay = hpet_readl(HPET_COUNTER) - offset;
+ } else {
+ spin_lock(&i8253_lock);
+ outb_p(0x00, 0x43);
+ delay = inb_p(0x40);
+ delay |= inb(0x40) << 8;
+ spin_unlock(&i8253_lock);
+ delay = LATCH - 1 - delay;
+ }

- sync_core();
- rdtscll(t);
- hpet.offset = (t - hpet.last_tsc) * (1000000L / HZ) / hpet.ticks + hpet.offset - 1000000L / HZ;
- if (hpet.offset >= 1000000L / HZ)
- hpet.offset = 0;
- hpet.ticks = min_t(long, max_t(long, (t - hpet.last_tsc) * (1000000L / HZ) / (1000000L / HZ - hpet.offset),
- cpu_khz * 1000/HZ * 15 / 16), cpu_khz * 1000/HZ * 16 / 15);
- hpet.last_tsc = t;
+ rdtscll_sync(&tsc);
+
+ if (vxtime.mode == VXTIME_HPET) {
+ if (offset - vxtime.last > hpet_tick) {
+ lost = (offset - vxtime.last) / hpet_tick - 1;
+ }
+
+ vxtime.last = offset;
+ } else {
+ offset = (((tsc - vxtime.last_tsc) *
+ vxtime.tsc_quot) >> 32) - tick_usec;
+
+ if (offset > tick_usec) {
+ lost = offset / tick_usec;
+ offset %= tick_usec;
+ }
+
+ vxtime.last_tsc = tsc - vxtime.quot * delay / vxtime.tsc_quot;
+
+ if ((((tsc - vxtime.last_tsc) *
+ vxtime.tsc_quot) >> 32) < offset)
+ vxtime.last_tsc = tsc -
+ (((long) offset << 32) / vxtime.tsc_quot) - 1;
+ }
+
+ if (lost) {
+ if (report_lost_ticks)
+ printk(KERN_WARNING "time.c: Lost %ld timer "
+ "tick(s)! (rip %016lx)\n",
+ (offset - vxtime.last) / hpet_tick - 1,
+ regs->rip);
+ // XXX The accounting of lost ticks is way off right
+ // now. -bos
+
+ // jiffies += lost;
}

/*
@@ -244,7 +303,7 @@
* If we have an externally synchronized Linux clock, then update CMOS clock
* accordingly every ~11 minutes. set_rtc_mmss() will be called in the jiffy
* closest to exactly 500 ms before the next second. If the update fails, we
- * don'tcare, as it'll be updated on the next turn, and the problem (time way
+ * don't care, as it'll be updated on the next turn, and the problem (time way
* off) isn't likely to go away much sooner anyway.
*/

@@ -254,6 +313,8 @@
rtc_update = xtime.tv_sec + 660;
}

+ call++;
+
write_sequnlock(&xtime_lock);

return IRQ_HANDLED;
@@ -263,6 +324,7 @@
{
unsigned int timeout, year, mon, day, hour, min, sec;
unsigned char last, this;
+ unsigned long flags;

/*
* The Linux interpretation of the CMOS clock register contents: When the
@@ -272,7 +334,7 @@
* standard 8.3 MHz ISA bus.
*/

- spin_lock(&rtc_lock);
+ spin_lock_irqsave(&rtc_lock, flags);

timeout = 1000000;
last = this = 0;
@@ -295,7 +357,7 @@
mon = CMOS_READ(RTC_MONTH);
year = CMOS_READ(RTC_YEAR);

- spin_unlock(&rtc_lock);
+ spin_unlock_irqrestore(&rtc_lock, flags);

/*
* We know that x86-64 always uses BCD format, no need to check the config
@@ -326,6 +388,32 @@

#define TICK_COUNT 100000000

+static unsigned int __init hpet_calibrate_tsc(void)
+{
+ int tsc_start, hpet_start;
+ int tsc_now, hpet_now;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ local_irq_disable();
+
+ hpet_start = hpet_readl(HPET_COUNTER);
+ rdtscl(tsc_start);
+
+ do {
+ local_irq_disable();
+ hpet_now = hpet_readl(HPET_COUNTER);
+ sync_core();
+ rdtscl(tsc_now);
+ local_irq_restore(flags);
+ } while ((tsc_now - tsc_start) < TICK_COUNT &&
+ (hpet_now - hpet_start) < TICK_COUNT);
+
+ return (tsc_now - tsc_start) * 1000000000L
+ / ((hpet_now - hpet_start) * hpet_period / 1000);
+}
+
+
/*
* pit_calibrate_tsc() uses the speaker output (channel 2) of
* the PIT. This is better than using the timer interrupt output,
@@ -344,6 +432,8 @@
local_irq_save(flags);
local_irq_disable();

+ spin_lock_irqsave(&i8253_lock, flags);
+
outb(0xb0, 0x43);
outb((1193182 / (1000 / 50)) & 0xff, 0x42);
outb((1193182 / (1000 / 50)) >> 8, 0x42);
@@ -353,42 +443,145 @@
sync_core();
rdtscll(end);

-
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&i8253_lock, flags);

return (end - start) / 50;
}

+static int hpet_init(void)
+{
+ unsigned int cfg, id;
+
+ if (!vxtime.hpet_address)
+ return -1;
+ set_fixmap_nocache(FIX_HPET_BASE, vxtime.hpet_address);
+
+/*
+ * Read the period, compute tick and quotient.
+ */
+
+ id = hpet_readl(HPET_ID);
+
+ if (!(id & HPET_ID_VENDOR) || !(id & HPET_ID_NUMBER) ||
+ !(id & HPET_ID_LEGSUP))
+ return -1;
+
+ hpet_period = hpet_readl(HPET_PERIOD);
+ if (hpet_period < 100000 || hpet_period > 100000000)
+ return -1;
+
+ hpet_tick = (tick_nsec + hpet_period / 2) / hpet_period;
+
+/*
+ * Stop the timers and reset the main counter.
+ */
+
+ cfg = hpet_readl(HPET_CFG);
+ cfg &= ~(HPET_CFG_ENABLE | HPET_CFG_LEGACY);
+ hpet_writel(cfg, HPET_CFG);
+ hpet_writel(0, HPET_COUNTER);
+ hpet_writel(0, HPET_COUNTER + 4);
+
+/*
+ * Set up timer 0, as periodic with first interrupt to happen at hpet_tick,
+ * and period also hpet_tick.
+ */
+
+ hpet_writel(HPET_T0_ENABLE | HPET_T0_PERIODIC | HPET_T0_SETVAL |
+ HPET_T0_32BIT, HPET_T0_CFG);
+ hpet_writel(hpet_tick, HPET_T0_CMP);
+ hpet_writel(hpet_tick, HPET_T0_CMP);
+
+/*
+ * Go!
+ */
+
+ cfg |= HPET_CFG_ENABLE | HPET_CFG_LEGACY;
+ hpet_writel(cfg, HPET_CFG);
+
+ return 0;
+}
+
void __init pit_init(void)
{
+ unsigned long flags;
+
+ spin_lock_irqsave(&i8253_lock, flags);
outb_p(0x34, 0x43); /* binary, mode 2, LSB/MSB, ch 0 */
outb_p(LATCH & 0xff, 0x40); /* LSB */
outb_p(LATCH >> 8, 0x40); /* MSB */
+ spin_unlock_irqrestore(&i8253_lock, flags);
}

int __init time_setup(char *str)
{
- hpet_report_lost_ticks = 1;
+ report_lost_ticks = 1;
return 1;
}

-static struct irqaction irq0 = { timer_interrupt, SA_INTERRUPT, 0, "timer", NULL, NULL};
+static struct irqaction irq0 = {
+ timer_interrupt, SA_INTERRUPT, 0, "timer", NULL, NULL
+};

extern void __init config_acpi_tables(void);

void __init time_init(void)
{
+ char *timename;
+
+#ifdef HPET_HACK_ENABLE_DANGEROUS
+ if (!vxtime.hpet_address) {
+ printk(KERN_WARNING "time.c: WARNING: Enabling HPET base "
+ "manually!\n");
+ outl(0x800038a0, 0xcf8);
+ outl(0xff000001, 0xcfc);
+ outl(0x800038a0, 0xcf8);
+ hpet_address = inl(0xcfc) & 0xfffffffe;
+ printk(KERN_WARNING "time.c: WARNING: Enabled HPET "
+ "at %#lx.\n", hpet_address);
+ }
+#endif
+
xtime.tv_sec = get_cmos_time();
xtime.tv_nsec = 0;

+ if (!hpet_init()) {
+ vxtime_hz = (1000000000000000L + hpet_period / 2) /
+ hpet_period;
+ cpu_khz = hpet_calibrate_tsc();
+ timename = "HPET";
+ } else {
pit_init();
- printk(KERN_INFO "time.c: Using 1.1931816 MHz PIT timer.\n");
cpu_khz = pit_calibrate_tsc();
+ timename = "PIT";
+ }
+
+ printk(KERN_INFO "time.c: Using %ld.%06ld MHz %s timer.\n",
+ vxtime_hz / 1000000, vxtime_hz % 1000000, timename);
printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
cpu_khz / 1000, cpu_khz % 1000);
- hpet.ticks = cpu_khz * (1000 / HZ);
- rdtscll(hpet.last_tsc);
+ vxtime.mode = VXTIME_TSC;
+ vxtime.quot = (1000000L << 32) / vxtime_hz;
+ vxtime.tsc_quot = (1000L << 32) / cpu_khz;
+ vxtime.hz = vxtime_hz;
+ rdtscll_sync(&vxtime.last_tsc);
setup_irq(0, &irq0);
}

+void __init time_init_smp(void)
+{
+ char *timetype;
+
+ if (vxtime.hpet_address) {
+ timetype = "HPET";
+ vxtime.last = hpet_readl(HPET_T0_CMP) - hpet_tick;
+ vxtime.mode = VXTIME_HPET;
+ do_gettimeoffset = do_gettimeoffset_hpet;
+ } else {
+ timetype = "PIT/TSC";
+ vxtime.mode = VXTIME_TSC;
+ }
+ printk(KERN_INFO "time.c: Using %s based timekeeping.\n", timetype);
+}
+
__setup("report_lost_ticks", time_setup);
--- linux-2.5/arch/x86_64/kernel/vsyscall.c 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/kernel/vsyscall.c 2003-06-10 10:46:18.000000000 -0700
@@ -78,13 +78,21 @@
do {
sequence = read_seqbegin(&__xtime_lock);

- sync_core();
- rdtscll(t);
sec = __xtime.tv_sec;
usec = (__xtime.tv_nsec / 1000) +
- (__jiffies - __wall_jiffies) * (1000000 / HZ) +
- (t - __hpet.last_tsc) * (1000000 / HZ) / __hpet.ticks + __hpet.offset;
+ (__jiffies - __wall_jiffies) * (1000000 / HZ);

+ if (__vxtime.mode == VXTIME_TSC) {
+ sync_core();
+ rdtscll(t);
+ usec += ((t - __vxtime.last_tsc) *
+ __vxtime.tsc_quot) >> 32;
+ } else {
+#if 0
+ usec += ((readl(fix_to_virt(VSYSCALL_HPET) + 0xf0) -
+ __vxtime.last) * __vxtime.quot) >> 32;
+#endif
+ }
} while (read_seqretry(&__xtime_lock, sequence));

tv->tv_sec = sec + usec / 1000000;
--- linux-2.5/arch/x86_64/Kconfig 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/Kconfig 2003-06-11 10:39:45.000000000 -0700
@@ -52,6 +52,18 @@
klogd/syslogd or the X server. You should normally N here, unless
you want to debug such a crash.

+config HPET_TIMER
+ bool
+ default n
+ help
+ Use the IA-PC HPET (High Precision Event Timer) to manage
+ time in preference to the PIT and RTC, if a HPET is
+ present. The HPET provides a stable time base on SMP
+ systems, unlike the RTC, but it is more expensive to access,
+ as it is off-chip. You can find the HPET spec at
+ <http://www.intel.com/labs/platcomp/hpet/hpetspec.htm>.
+
+ If unsure, say Y.

config GENERIC_ISA_DMA
bool
--- linux-2.5/include/asm-x86_64/vsyscall.h 2003-06-11 11:43:32.000000000 -0700
+++ x86-64-2.5/include/asm-x86_64/vsyscall.h 2003-06-11 10:21:35.000000000 -0700
@@ -15,7 +15,7 @@

#ifdef __KERNEL__

-#define __section_hpet __attribute__ ((unused, __section__ (".hpet"), aligned(16)))
+#define __section_vxtime __attribute__ ((unused, __section__ (".vxtime"), aligned(16)))
#define __section_wall_jiffies __attribute__ ((unused, __section__ (".wall_jiffies"), aligned(16)))
#define __section_jiffies __attribute__ ((unused, __section__ (".jiffies"), aligned(16)))
#define __section_sys_tz __attribute__ ((unused, __section__ (".sys_tz"), aligned(16)))
@@ -23,22 +23,24 @@
#define __section_xtime __attribute__ ((unused, __section__ (".xtime"), aligned(16)))
#define __section_xtime_lock __attribute__ ((unused, __section__ (".xtime_lock"), aligned(L1_CACHE_BYTES)))

+#define VXTIME_TSC 1
+#define VXTIME_HPET 2

-struct hpet_data {
- long address; /* base address */
+struct vxtime_data {
+ long hpet_address; /* HPET base address */
unsigned long hz; /* HPET clocks / sec */
- int trigger; /* value at last interrupt */
int last;
- int offset;
unsigned long last_tsc;
- long ticks;
+ long quot;
+ long tsc_quot;
+ int mode;
};

#define hpet_readl(a) readl(fix_to_virt(FIX_HPET_BASE) + a)
#define hpet_writel(d,a) writel(d, fix_to_virt(FIX_HPET_BASE) + a)

/* vsyscall space (readonly) */
-extern struct hpet_data __hpet;
+extern struct vxtime_data __vxtime;
extern struct timespec __xtime;
extern volatile unsigned long __jiffies;
extern unsigned long __wall_jiffies;
@@ -46,7 +48,7 @@
extern seqlock_t __xtime_lock;

/* kernel space (writeable) */
-extern struct hpet_data hpet;
+extern struct vxtime_data vxtime;
extern unsigned long wall_jiffies;
extern struct timezone sys_tz;
extern int sysctl_vsyscall;
--- linux-2.5/arch/x86_64/kernel/smpboot.c 2003-06-11 11:43:09.000000000 -0700
+++ x86-64-2.5/arch/x86_64/kernel/smpboot.c 2003-06-10 12:30:52.000000000 -0700
@@ -67,6 +67,8 @@
/* Set when the idlers are all forked */
int smp_threads_ready;

+extern void time_init_smp(void);
+
/*
* Trampoline 80x86 program as an array.
*/
@@ -760,7 +762,7 @@
if (APIC_init_uniprocessor())
printk(KERN_NOTICE "Local APIC not detected."
" Using dummy APIC emulation.\n");
- return;
+ goto smp_done;
}

/*
@@ -784,7 +786,7 @@
cpu_online_map = phys_cpu_present_map = 1;
phys_cpu_present_map = 1;
disable_apic = 1;
- return;
+ goto smp_done;
}

verify_local_APIC();
@@ -799,7 +801,7 @@
cpu_online_map = phys_cpu_present_map = 1;
phys_cpu_present_map = 1;
disable_apic = 1;
- return;
+ goto smp_done;
}

connect_bsp_APIC();
@@ -883,6 +885,9 @@
*/
if (cpu_has_tsc && cpucount)
synchronize_tsc_bp();
+
+ smp_done:
+ time_init_smp();
}

/* These are wrappers to interface to the new boot process. Someone

--=_courier-12950-1055357570-0001-2--