X-Git-Url: http://pilppa.org/gitweb/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Ftime.c;h=ea00915d393a74a337c9867556370ea7d95e08c8;hb=31679f38d88696ed032d59e457f1605c97e7d719;hp=ebbee6f59ff5f5c390b13085f9cf2f8b8fad6fc2;hpb=4d3ce21fa9d2eaeda113aa2f9c2da80d972bef64;p=linux-2.6-omap-h63xx.git

diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index ebbee6f59ff..ea00915d393 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -24,10 +24,13 @@
 #include <linux/device.h>
 #include <linux/sysdev.h>
 #include <linux/bcd.h>
+#include <linux/notifier.h>
+#include <linux/cpu.h>
 #include <linux/kallsyms.h>
 #include <linux/acpi.h>
 #ifdef CONFIG_ACPI
 #include <acpi/achware.h>	/* for PM timer frequency */
+#include <acpi/acpi_bus.h>
 #endif
 #include <asm/8253pit.h>
 #include <asm/pgtable.h>
@@ -48,7 +51,7 @@ static void cpufreq_delayed_get(void);
 extern void i8254_timer_resume(void);
 extern int using_apic_timer;
 
-static char *time_init_gtod(void);
+static char *timename = NULL;
 
 DEFINE_SPINLOCK(rtc_lock);
 EXPORT_SYMBOL(rtc_lock);
@@ -186,20 +189,15 @@ unsigned long profile_pc(struct pt_regs *regs)
 {
 	unsigned long pc = instruction_pointer(regs);
 
-	/* Assume the lock function has either no stack frame or only a single 
-	   word.  This checks if the address on the stack looks like a kernel 
-	   text address.
-	   There is a small window for false hits, but in that case the tick
-	   is just accounted to the spinlock function.
-	   Better would be to write these functions in assembler again
-	   and check exactly. */
-	if (in_lock_functions(pc)) {
-		char *v = *(char **)regs->rsp;
-		if ((v >= _stext && v <= _etext) ||
-			(v >= _sinittext && v <= _einittext) ||
-			(v >= (char *)MODULES_VADDR  && v <= (char *)MODULES_END))
-			return (unsigned long)v;
-		return ((unsigned long *)regs->rsp)[1];
+	/* Assume the lock function has either no stack frame or a copy
+	   of eflags from PUSHF
+	   Eflags always has bits 22 and up cleared unlike kernel addresses. */
+	if (!user_mode(regs) && in_lock_functions(pc)) {
+		unsigned long *sp = (unsigned long *)regs->rsp;
+		if (sp[0] >> 22)
+			return sp[0];
+		if (sp[1] >> 22)
+			return sp[1];
 	}
 	return pc;
 }
@@ -889,14 +887,20 @@ int __init time_setup(char *str)
 }
 
 static struct irqaction irq0 = {
-	timer_interrupt, SA_INTERRUPT, CPU_MASK_NONE, "timer", NULL, NULL
+	timer_interrupt, IRQF_DISABLED, CPU_MASK_NONE, "timer", NULL, NULL
 };
 
-void __init time_init(void)
+static int __cpuinit
+time_cpu_notifier(struct notifier_block *nb, unsigned long action, void *hcpu)
 {
-	char *timename;
-	char *gtod;
+	unsigned cpu = (unsigned long) hcpu;
+	if (action == CPU_ONLINE)
+		vsyscall_set_cpu(cpu);
+	return NOTIFY_DONE;
+}
 
+void __init time_init(void)
+{
 	if (nohpet)
 		vxtime.hpet_address = 0;
 
@@ -930,18 +934,19 @@ void __init time_init(void)
 	}
 
 	vxtime.mode = VXTIME_TSC;
-	gtod = time_init_gtod();
-
-	printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
-	       vxtime_hz / 1000000, vxtime_hz % 1000000, timename, gtod);
-	printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
-		cpu_khz / 1000, cpu_khz % 1000);
 	vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
 	vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
 	vxtime.last_tsc = get_cycles_sync();
 	setup_irq(0, &irq0);
 
 	set_cyc2ns_scale(cpu_khz);
+
+	hotcpu_notifier(time_cpu_notifier, 0);
+	time_cpu_notifier(NULL, CPU_ONLINE, (void *)(long)smp_processor_id());
+
+#ifndef CONFIG_SMP
+	time_init_gtod();
+#endif
 }
 
 /*
@@ -953,11 +958,18 @@ __cpuinit int unsynchronized_tsc(void)
 #ifdef CONFIG_SMP
 	if (apic_is_clustered_box())
 		return 1;
- 	/* Intel systems are normally all synchronized. Exceptions
- 	   are handled in the check above. */
- 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL)
- 		return 0;
 #endif
+	/* Most intel systems have synchronized TSCs except for
+	   multi node systems */
+ 	if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) {
+#ifdef CONFIG_ACPI
+		/* But TSC doesn't tick in C3 so don't use it there */
+		if (acpi_fadt.length > 0 && acpi_fadt.plvl3_lat < 100)
+			return 1;
+#endif
+ 		return 0;
+	}
+
  	/* Assume multi socket systems are not synchronized */
  	return num_present_cpus() > 1;
 }
@@ -965,12 +977,18 @@ __cpuinit int unsynchronized_tsc(void)
 /*
  * Decide what mode gettimeofday should use.
  */
-__init static char *time_init_gtod(void)
+void time_init_gtod(void)
 {
 	char *timetype;
 
 	if (unsynchronized_tsc())
 		notsc = 1;
+
+ 	if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
+		vgetcpu_mode = VGETCPU_RDTSCP;
+	else
+		vgetcpu_mode = VGETCPU_LSL;
+
 	if (vxtime.hpet_address && notsc) {
 		timetype = hpet_use_timer ? "HPET" : "PIT/HPET";
 		if (hpet_use_timer)
@@ -993,7 +1011,16 @@ __init static char *time_init_gtod(void)
 		timetype = hpet_use_timer ? "HPET/TSC" : "PIT/TSC";
 		vxtime.mode = VXTIME_TSC;
 	}
-	return timetype;
+
+	printk(KERN_INFO "time.c: Using %ld.%06ld MHz WALL %s GTOD %s timer.\n",
+	       vxtime_hz / 1000000, vxtime_hz % 1000000, timename, timetype);
+	printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
+		cpu_khz / 1000, cpu_khz % 1000);
+	vxtime.quot = (USEC_PER_SEC << US_SCALE) / vxtime_hz;
+	vxtime.tsc_quot = (USEC_PER_MSEC << US_SCALE) / cpu_khz;
+	vxtime.last_tsc = get_cycles_sync();
+
+	set_cyc2ns_scale(cpu_khz);
 }
 
 __setup("report_lost_ticks", time_setup);