plain text document attachment (xx-paravirt-time.patch)
General time changes for paravirt_ops.
Signed-off-by: Steven Rostedt srostedt@xxxxxxxxxx
Signed-off-by: Glauber de Oliveira Costa <gcosta@xxxxxxxxxx>
Index: clean-start/include/asm-x86_64/time.h
===================================================================
--- /dev/null
+++ clean-start/include/asm-x86_64/time.h
@@ -0,0 +1,18 @@
+#ifndef _ASM_X86_64_TIME_H
+#define _ASM_X86_64_TIME_H
+
+inline void time_init_hook(void);
+unsigned long do_get_cmos_time(void);
+void do_set_rtc_mmss(unsigned long nowtime);
+
+#ifdef CONFIG_PARAVIRT
+#include <asm/paravirt.h>
+#else /* !CONFIG_PARAVIRT */
+
+#define get_wallclock() do_get_cmos_time()
+#define set_wallclock(x) do_set_rtc_mmss(x)
+#define do_time_init() time_init_hook()
+
+#endif /* CONFIG_PARAVIRT */
+
+#endif
Index: clean-start/arch/x86_64/kernel/time.c
===================================================================
--- clean-start.orig/arch/x86_64/kernel/time.c
+++ clean-start/arch/x86_64/kernel/time.c
@@ -42,6 +42,7 @@
#include <linux/cpufreq.h>
#include <linux/hpet.h>
#include <asm/apic.h>
+#include <asm/time.h>
#ifdef CONFIG_CPU_FREQ
static void cpufreq_delayed_get(void);
@@ -204,17 +205,11 @@ EXPORT_SYMBOL(profile_pc);
* sheet for details.
*/
-static void set_rtc_mmss(unsigned long nowtime)
+void do_set_rtc_mmss(unsigned long nowtime)
{
int real_seconds, real_minutes, cmos_minutes;
unsigned char control, freq_select;
-/*
- * IRQs are disabled when we're called from the timer interrupt,
- * no need for spin_lock_irqsave()
- */
-
- spin_lock(&rtc_lock);
/*
* Tell the clock it's being set and stop it.
@@ -263,9 +258,18 @@ static void set_rtc_mmss(unsigned long n
CMOS_WRITE(control, RTC_CONTROL);
CMOS_WRITE(freq_select, RTC_FREQ_SELECT);
- spin_unlock(&rtc_lock);
}
+static void set_rtc_mmss(unsigned long nowtime)
+{
+/*
+ * IRQs are disabled when we're called from the timer interrupt,
+ * no need for spin_lock_irqsave()
+ */
+ spin_lock(&rtc_lock);
+ set_wallclock(nowtime);
+ spin_unlock(&rtc_lock);
+}
/* monotonic_clock(): returns # of nanoseconds passed since time_init()
* Note: This function is required to return accurate
@@ -494,13 +498,11 @@ unsigned long long sched_clock(void)
return cycles_2_ns(a);
}
-static unsigned long get_cmos_time(void)
+unsigned long do_get_cmos_time(void)
{
unsigned int year, mon, day, hour, min, sec;
- unsigned long flags;
unsigned extyear = 0;
- spin_lock_irqsave(&rtc_lock, flags);
do {
sec = CMOS_READ(RTC_SECONDS);
@@ -516,7 +518,6 @@ static unsigned long get_cmos_time(void)
#endif
} while (sec != CMOS_READ(RTC_SECONDS));
- spin_unlock_irqrestore(&rtc_lock, flags);
/*
* We know that x86-64 always uses BCD format, no need to check the
@@ -545,6 +546,15 @@ static unsigned long get_cmos_time(void)
return mktime(year, mon, day, hour, min, sec);
}
+static unsigned long get_cmos_time(void)
+{
+ unsigned long retval, flags;
+ /* XXX : lock being held more than necessary. */
+ spin_lock_irqsave(&rtc_lock, flags);
+ retval = get_wallclock();
+ spin_unlock_irqrestore(&rtc_lock, flags);
+ return retval;
+}
#ifdef CONFIG_CPU_FREQ
/* Frequency scaling support. Adjust the TSC based timer when the cpu frequency
@@ -893,6 +903,11 @@ static struct irqaction irq0 = {
timer_interrupt, IRQF_DISABLED, CPU_MASK_NONE, "timer", NULL, NULL
};
+inline void time_init_hook()
+{
+ setup_irq(0, &irq0);
+}
+
void __init time_init(void)
{
if (nohpet)
@@ -932,7 +947,7 @@ void __init time_init(void)
vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
vxtime.last_tsc = get_cycles_sync();
set_cyc2ns_scale(cpu_khz);
- setup_irq(0, &irq0);
+ do_time_init();
#ifndef CONFIG_SMP
time_init_gtod();
Index: clean-start/include/asm-x86_64/timex.h
===================================================================
--- clean-start.orig/include/asm-x86_64/timex.h
+++ clean-start/include/asm-x86_64/timex.h
@@ -31,14 +31,29 @@ static __always_inline cycles_t get_cycl
{
unsigned long long ret;
unsigned eax;
+ unsigned int (*fn)(unsigned int) = &cpuid_eax;
/* Don't do an additional sync on CPUs where we know
RDTSC is already synchronous. */
- alternative_io("cpuid", ASM_NOP2, X86_FEATURE_SYNC_RDTSC,
- "=a" (eax), "0" (1) : "ebx","ecx","edx","memory");
+ alternative_io("call *%3", ASM_NOP2, X86_FEATURE_SYNC_RDTSC,
+ "=a" (eax) , "D" (1) , "m" (fn));
rdtscll(ret);
return ret;
}
+/* Inside a vsyscall, we cannot call paravirt functions. (like rdtsc
+ * and cpuid). For the host, use this function instead */
+static __always_inline cycles_t vget_cycles_sync(void)
+{
+ unsigned long ret;
+ unsigned eax;
+ /* Don't do an additional sync on CPUs where we know
+ RDTSC is already synchronous. */
+ alternative_io("cpuid", ASM_NOP2, X86_FEATURE_SYNC_RDTSC,
+ "=a" (eax), "0" (1) : "ebx","ecx","edx","memory");
+
+ asm volatile("rdtsc" : "=A" (ret));
+ return ret;
+}
extern unsigned int cpu_khz;
extern int read_current_timer(unsigned long *timer_value);
--
_______________________________________________
Virtualization mailing list
Virtualization@xxxxxxxxxxxxxx
https://lists.osdl.org/mailman/listinfo/virtualization
