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the use/inability to use this patch. Any use of the attached is considered
acceptance of the above.]
From: Alok N Kataria <[email protected]>
Unify the clocksource code.
Unify the tsc_init code.
Signed-off-by: Alok N Kataria <[email protected]>
Signed-off-by: Dan Hecht <[email protected]>
---
arch/x86/kernel/Makefile | 2
arch/x86/kernel/time_64.c | 32 -------
arch/x86/kernel/tsc.c | 212 ++++++++++++++++++++++++++++++++++++++++++++-
arch/x86/kernel/tsc_32.c | 188 ----------------------------------------
arch/x86/kernel/tsc_64.c | 106 -----------------------
include/asm-x86/apic.h | 7 +
include/asm-x86/delay.h | 4 +
include/asm-x86/time.h | 2
include/asm-x86/tsc.h | 1
9 files changed, 224 insertions(+), 330 deletions(-)
delete mode 100644 arch/x86/kernel/tsc_32.c
delete mode 100644 arch/x86/kernel/tsc_64.c
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 631141b..8f60218 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -34,7 +34,7 @@ obj-$(CONFIG_X86_64) += syscall_64.o vsyscall_64.o
obj-y += bootflag.o e820.o
obj-y += pci-dma.o quirks.o i8237.o topology.o kdebugfs.o
obj-y += alternative.o i8253.o pci-nommu.o
-obj-y += tsc_$(BITS).o io_delay.o rtc.o tsc.o
+obj-y += tsc.o io_delay.o rtc.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline.o
obj-y += process.o
diff --git a/arch/x86/kernel/time_64.c b/arch/x86/kernel/time_64.c
index c6ac4da..e3d49c5 100644
--- a/arch/x86/kernel/time_64.c
+++ b/arch/x86/kernel/time_64.c
@@ -56,7 +56,7 @@ static irqreturn_t timer_event_interrupt(int irq, void *dev_id)
/* calibrate_cpu is used on systems with fixed rate TSCs to determine
* processor frequency */
#define TICK_COUNT 100000000
-static unsigned long __init calibrate_cpu(void)
+unsigned long __init calibrate_cpu(void)
{
int tsc_start, tsc_now;
int i, no_ctr_free;
@@ -114,41 +114,13 @@ void __init hpet_time_init(void)
setup_irq(0, &irq0);
}
-extern void set_cyc2ns_scale(unsigned long cpu_khz, int cpu);
-
void __init time_init(void)
{
- int cpu;
-
- cpu_khz = calculate_cpu_khz();
- tsc_khz = cpu_khz;
-
- if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
- (boot_cpu_data.x86_vendor == X86_VENDOR_AMD))
- cpu_khz = calibrate_cpu();
-
- lpj_fine = ((unsigned long)tsc_khz * 1000)/HZ;
-
- if (unsynchronized_tsc())
- mark_tsc_unstable("TSCs unsynchronized");
-
+ tsc_init();
if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
vgetcpu_mode = VGETCPU_RDTSCP;
else
vgetcpu_mode = VGETCPU_LSL;
- printk(KERN_INFO "time.c: Detected %d.%03d MHz processor.\n",
- cpu_khz / 1000, cpu_khz % 1000);
-
- /*
- * Secondary CPUs do not run through tsc_init(), so set up
- * all the scale factors for all CPUs, assuming the same
- * speed as the bootup CPU. (cpufreq notifiers will fix this
- * up if their speed diverges)
- */
- for_each_possible_cpu(cpu)
- set_cyc2ns_scale(cpu_khz, cpu);
-
- init_tsc_clocksource();
late_time_init = choose_time_init();
}
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index 595f78a..94c16bd 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -5,8 +5,16 @@
#include <linux/timer.h>
#include <linux/acpi_pmtmr.h>
#include <linux/cpufreq.h>
+#include <linux/dmi.h>
+#include <linux/delay.h>
+#include <linux/clocksource.h>
+#include <linux/percpu.h>
#include <asm/hpet.h>
+#include <asm/timer.h>
+#include <asm/vgtod.h>
+#include <asm/time.h>
+#include <asm/delay.h>
unsigned int cpu_khz; /* TSC clocks / usec, not used here */
EXPORT_SYMBOL(cpu_khz);
@@ -16,12 +24,12 @@ EXPORT_SYMBOL(tsc_khz);
/*
* TSC can be unstable due to cpufreq or due to unsynced TSCs
*/
-int tsc_unstable;
+static int tsc_unstable;
/* native_sched_clock() is called before tsc_init(), so
we must start with the TSC soft disabled to prevent
erroneous rdtsc usage on !cpu_has_tsc processors */
-int tsc_disabled = -1;
+static int tsc_disabled = -1;
/*
* Scheduler clock - returns current time in nanosec units.
@@ -241,7 +249,7 @@ EXPORT_SYMBOL(recalibrate_cpu_khz);
DEFINE_PER_CPU(unsigned long, cyc2ns);
-void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
+static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)
{
unsigned long long tsc_now, ns_now;
unsigned long flags, *scale;
@@ -329,3 +337,201 @@ static int __init cpufreq_tsc(void)
core_initcall(cpufreq_tsc);
#endif /* CONFIG_CPU_FREQ */
+
+/* clocksource code */
+
+static struct clocksource clocksource_tsc;
+
+/*
+ * We compare the TSC to the cycle_last value in the clocksource
+ * structure to avoid a nasty time-warp. This can be observed in a
+ * very small window right after one CPU updated cycle_last under
+ * xtime/vsyscall_gtod lock and the other CPU reads a TSC value which
+ * is smaller than the cycle_last reference value due to a TSC which
+ * is slighty behind. This delta is nowhere else observable, but in
+ * that case it results in a forward time jump in the range of hours
+ * due to the unsigned delta calculation of the time keeping core
+ * code, which is necessary to support wrapping clocksources like pm
+ * timer.
+ */
+static cycle_t read_tsc(void)
+{
+ cycle_t ret = (cycle_t)get_cycles();
+
+ return ret >= clocksource_tsc.cycle_last ?
+ ret : clocksource_tsc.cycle_last;
+}
+
+static cycle_t __vsyscall_fn vread_tsc(void)
+{
+ cycle_t ret = (cycle_t)vget_cycles();
+
+ return ret >= __vsyscall_gtod_data.clock.cycle_last ?
+ ret : __vsyscall_gtod_data.clock.cycle_last;
+}
+
+static struct clocksource clocksource_tsc = {
+ .name = "tsc",
+ .rating = 300,
+ .read = read_tsc,
+ .mask = CLOCKSOURCE_MASK(64),
+ .shift = 22,
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS |
+ CLOCK_SOURCE_MUST_VERIFY,
+#ifdef CONFIG_X86_64
+ .vread = vread_tsc,
+#endif
+};
+
+void mark_tsc_unstable(char *reason)
+{
+ if (!tsc_unstable) {
+ tsc_unstable = 1;
+ printk("Marking TSC unstable due to %s\n", reason);
+ /* Change only the rating, when not registered */
+ if (clocksource_tsc.mult)
+ clocksource_change_rating(&clocksource_tsc, 0);
+ else
+ clocksource_tsc.rating = 0;
+ }
+}
+
+EXPORT_SYMBOL_GPL(mark_tsc_unstable);
+
+static int __init dmi_mark_tsc_unstable(const struct dmi_system_id *d)
+{
+ printk(KERN_NOTICE "%s detected: marking TSC unstable.\n",
+ d->ident);
+ tsc_unstable = 1;
+ return 0;
+}
+
+/* List of systems that have known TSC problems */
+static struct dmi_system_id __initdata bad_tsc_dmi_table[] = {
+ {
+ .callback = dmi_mark_tsc_unstable,
+ .ident = "IBM Thinkpad 380XD",
+ .matches = {
+ DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
+ DMI_MATCH(DMI_BOARD_NAME, "2635FA0"),
+ },
+ },
+ {}
+};
+
+/*
+ * Geode_LX - the OLPC CPU has a possibly a very reliable TSC
+ */
+#ifdef CONFIG_MGEODE_LX
+/* RTSC counts during suspend */
+#define RTSC_SUSP 0x100
+
+static void __init check_geode_tsc_reliable(void)
+{
+ unsigned long res_low, res_high;
+
+ rdmsr_safe(MSR_GEODE_BUSCONT_CONF0, &res_low, &res_high);
+ if (res_low & RTSC_SUSP)
+ clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY;
+}
+#else
+static inline void check_geode_tsc_reliable(void) { }
+#endif
+
+/*
+ * Make an educated guess if the TSC is trustworthy and synchronized
+ * over all CPUs.
+ */
+__cpuinit int unsynchronized_tsc(void)
+{
+ if (!cpu_has_tsc || tsc_unstable)
+ return 1;
+
+#ifdef CONFIG_SMP
+ if (apic_is_clustered_box())
+ return 1;
+#endif
+
+ if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
+ return 0;
+ /*
+ * Intel systems are normally all synchronized.
+ * Exceptions must mark TSC as unstable:
+ */
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
+ /* assume multi socket systems are not synchronized: */
+ if (num_possible_cpus() > 1)
+ tsc_unstable = 1;
+ }
+
+ return tsc_unstable;
+}
+
+static void __init init_tsc_clocksource(void)
+{
+ clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
+ clocksource_tsc.shift);
+ /* lower the rating if we already know its unstable: */
+ if (check_tsc_unstable()) {
+ clocksource_tsc.rating = 0;
+ clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
+ }
+ clocksource_register(&clocksource_tsc);
+}
+
+void __init tsc_init(void)
+{
+ u64 lpj;
+ int cpu;
+
+ if (!cpu_has_tsc)
+ return;
+
+ cpu_khz = calculate_cpu_khz();
+ tsc_khz = cpu_khz;
+
+ if (!cpu_khz) {
+ mark_tsc_unstable("could not calculate TSC khz");
+ return;
+ }
+
+#ifdef CONFIG_X86_64
+ if (cpu_has(&boot_cpu_data, X86_FEATURE_CONSTANT_TSC) &&
+ (boot_cpu_data.x86_vendor == X86_VENDOR_AMD))
+ cpu_khz = calibrate_cpu();
+#endif
+
+ lpj = ((u64)tsc_khz * 1000);
+ do_div(lpj, HZ);
+ lpj_fine = lpj;
+
+ printk("Detected %lu.%03lu MHz processor.\n",
+ (unsigned long)cpu_khz / 1000,
+ (unsigned long)cpu_khz % 1000);
+
+ /*
+ * Secondary CPUs do not run through tsc_init(), so set up
+ * all the scale factors for all CPUs, assuming the same
+ * speed as the bootup CPU. (cpufreq notifiers will fix this
+ * up if their speed diverges)
+ */
+ for_each_possible_cpu(cpu)
+ set_cyc2ns_scale(cpu_khz, cpu);
+
+ if (tsc_disabled > 0)
+ return;
+
+ /* now allow native_sched_clock() to use rdtsc */
+ tsc_disabled = 0;
+
+ use_tsc_delay();
+ /* Check and install the TSC clocksource */
+ dmi_check_system(bad_tsc_dmi_table);
+
+ if (unsynchronized_tsc())
+ mark_tsc_unstable("TSCs unsynchronized");
+
+ check_geode_tsc_reliable();
+ init_tsc_clocksource();
+}
+
diff --git a/arch/x86/kernel/tsc_32.c b/arch/x86/kernel/tsc_32.c
deleted file mode 100644
index bbc153d..0000000
--- a/arch/x86/kernel/tsc_32.c
+++ /dev/null
@@ -1,188 +0,0 @@
-#include <linux/sched.h>
-#include <linux/clocksource.h>
-#include <linux/workqueue.h>
-#include <linux/delay.h>
-#include <linux/cpufreq.h>
-#include <linux/jiffies.h>
-#include <linux/init.h>
-#include <linux/dmi.h>
-#include <linux/percpu.h>
-
-#include <asm/delay.h>
-#include <asm/tsc.h>
-#include <asm/io.h>
-#include <asm/timer.h>
-
-#include "mach_timer.h"
-
-extern int tsc_unstable;
-extern int tsc_disabled;
-
-/* clock source code */
-
-static struct clocksource clocksource_tsc;
-
-/*
- * We compare the TSC to the cycle_last value in the clocksource
- * structure to avoid a nasty time-warp issue. This can be observed in
- * a very small window right after one CPU updated cycle_last under
- * xtime lock and the other CPU reads a TSC value which is smaller
- * than the cycle_last reference value due to a TSC which is slighty
- * behind. This delta is nowhere else observable, but in that case it
- * results in a forward time jump in the range of hours due to the
- * unsigned delta calculation of the time keeping core code, which is
- * necessary to support wrapping clocksources like pm timer.
- */
-static cycle_t read_tsc(void)
-{
- cycle_t ret;
-
- rdtscll(ret);
-
- return ret >= clocksource_tsc.cycle_last ?
- ret : clocksource_tsc.cycle_last;
-}
-
-static struct clocksource clocksource_tsc = {
- .name = "tsc",
- .rating = 300,
- .read = read_tsc,
- .mask = CLOCKSOURCE_MASK(64),
- .mult = 0, /* to be set */
- .shift = 22,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS |
- CLOCK_SOURCE_MUST_VERIFY,
-};
-
-void mark_tsc_unstable(char *reason)
-{
- if (!tsc_unstable) {
- tsc_unstable = 1;
- printk("Marking TSC unstable due to: %s.\n", reason);
- /* Can be called before registration */
- if (clocksource_tsc.mult)
- clocksource_change_rating(&clocksource_tsc, 0);
- else
- clocksource_tsc.rating = 0;
- }
-}
-EXPORT_SYMBOL_GPL(mark_tsc_unstable);
-
-static int __init dmi_mark_tsc_unstable(const struct dmi_system_id *d)
-{
- printk(KERN_NOTICE "%s detected: marking TSC unstable.\n",
- d->ident);
- tsc_unstable = 1;
- return 0;
-}
-
-/* List of systems that have known TSC problems */
-static struct dmi_system_id __initdata bad_tsc_dmi_table[] = {
- {
- .callback = dmi_mark_tsc_unstable,
- .ident = "IBM Thinkpad 380XD",
- .matches = {
- DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
- DMI_MATCH(DMI_BOARD_NAME, "2635FA0"),
- },
- },
- {}
-};
-
-/*
- * Make an educated guess if the TSC is trustworthy and synchronized
- * over all CPUs.
- */
-__cpuinit int unsynchronized_tsc(void)
-{
- if (!cpu_has_tsc || tsc_unstable)
- return 1;
-
- /* Anything with constant TSC should be synchronized */
- if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
- return 0;
-
- /*
- * Intel systems are normally all synchronized.
- * Exceptions must mark TSC as unstable:
- */
- if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
- /* assume multi socket systems are not synchronized: */
- if (num_possible_cpus() > 1)
- tsc_unstable = 1;
- }
- return tsc_unstable;
-}
-
-/*
- * Geode_LX - the OLPC CPU has a possibly a very reliable TSC
- */
-#ifdef CONFIG_MGEODE_LX
-/* RTSC counts during suspend */
-#define RTSC_SUSP 0x100
-
-static void __init check_geode_tsc_reliable(void)
-{
- unsigned long res_low, res_high;
-
- rdmsr_safe(MSR_GEODE_BUSCONT_CONF0, &res_low, &res_high);
- if (res_low & RTSC_SUSP)
- clocksource_tsc.flags &= ~CLOCK_SOURCE_MUST_VERIFY;
-}
-#else
-static inline void check_geode_tsc_reliable(void) { }
-#endif
-
-
-void __init tsc_init(void)
-{
- int cpu;
- u64 lpj;
-
- if (!cpu_has_tsc || tsc_disabled > 0)
- return;
-
- cpu_khz = calculate_cpu_khz();
- tsc_khz = cpu_khz;
-
- if (!cpu_khz) {
- mark_tsc_unstable("could not calculate TSC khz");
- return;
- }
-
- lpj = ((u64)tsc_khz * 1000);
- do_div(lpj, HZ);
- lpj_fine = lpj;
-
- /* now allow native_sched_clock() to use rdtsc */
- tsc_disabled = 0;
-
- printk("Detected %lu.%03lu MHz processor.\n",
- (unsigned long)cpu_khz / 1000,
- (unsigned long)cpu_khz % 1000);
-
- /*
- * Secondary CPUs do not run through tsc_init(), so set up
- * all the scale factors for all CPUs, assuming the same
- * speed as the bootup CPU. (cpufreq notifiers will fix this
- * up if their speed diverges)
- */
- for_each_possible_cpu(cpu)
- set_cyc2ns_scale(cpu_khz, cpu);
-
- use_tsc_delay();
-
- /* Check and install the TSC clocksource */
- dmi_check_system(bad_tsc_dmi_table);
-
- unsynchronized_tsc();
- check_geode_tsc_reliable();
- clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
- clocksource_tsc.shift);
- /* lower the rating if we already know its unstable: */
- if (check_tsc_unstable()) {
- clocksource_tsc.rating = 0;
- clocksource_tsc.flags &= ~CLOCK_SOURCE_IS_CONTINUOUS;
- }
- clocksource_register(&clocksource_tsc);
-}
diff --git a/arch/x86/kernel/tsc_64.c b/arch/x86/kernel/tsc_64.c
deleted file mode 100644
index 80a274b..0000000
--- a/arch/x86/kernel/tsc_64.c
+++ /dev/null
@@ -1,106 +0,0 @@
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/interrupt.h>
-#include <linux/init.h>
-#include <linux/clocksource.h>
-#include <linux/time.h>
-#include <linux/acpi.h>
-#include <linux/cpufreq.h>
-#include <linux/acpi_pmtmr.h>
-
-#include <asm/hpet.h>
-#include <asm/timex.h>
-#include <asm/timer.h>
-#include <asm/vgtod.h>
-
-extern int tsc_unstable;
-extern int tsc_disabled;
-
-/*
- * Make an educated guess if the TSC is trustworthy and synchronized
- * over all CPUs.
- */
-__cpuinit int unsynchronized_tsc(void)
-{
- if (tsc_unstable)
- return 1;
-
-#ifdef CONFIG_SMP
- if (apic_is_clustered_box())
- return 1;
-#endif
-
- if (boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
- return 0;
-
- /* Assume multi socket systems are not synchronized */
- return num_present_cpus() > 1;
-}
-
-static struct clocksource clocksource_tsc;
-
-/*
- * We compare the TSC to the cycle_last value in the clocksource
- * structure to avoid a nasty time-warp. This can be observed in a
- * very small window right after one CPU updated cycle_last under
- * xtime/vsyscall_gtod lock and the other CPU reads a TSC value which
- * is smaller than the cycle_last reference value due to a TSC which
- * is slighty behind. This delta is nowhere else observable, but in
- * that case it results in a forward time jump in the range of hours
- * due to the unsigned delta calculation of the time keeping core
- * code, which is necessary to support wrapping clocksources like pm
- * timer.
- */
-static cycle_t read_tsc(void)
-{
- cycle_t ret = (cycle_t)get_cycles();
-
- return ret >= clocksource_tsc.cycle_last ?
- ret : clocksource_tsc.cycle_last;
-}
-
-static cycle_t __vsyscall_fn vread_tsc(void)
-{
- cycle_t ret = (cycle_t)vget_cycles();
-
- return ret >= __vsyscall_gtod_data.clock.cycle_last ?
- ret : __vsyscall_gtod_data.clock.cycle_last;
-}
-
-static struct clocksource clocksource_tsc = {
- .name = "tsc",
- .rating = 300,
- .read = read_tsc,
- .mask = CLOCKSOURCE_MASK(64),
- .shift = 22,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS |
- CLOCK_SOURCE_MUST_VERIFY,
- .vread = vread_tsc,
-};
-
-void mark_tsc_unstable(char *reason)
-{
- if (!tsc_unstable) {
- tsc_unstable = 1;
- printk("Marking TSC unstable due to %s\n", reason);
- /* Change only the rating, when not registered */
- if (clocksource_tsc.mult)
- clocksource_change_rating(&clocksource_tsc, 0);
- else
- clocksource_tsc.rating = 0;
- }
-}
-EXPORT_SYMBOL_GPL(mark_tsc_unstable);
-
-void __init init_tsc_clocksource(void)
-{
- if (tsc_disabled > 0)
- return;
-
- clocksource_tsc.mult = clocksource_khz2mult(tsc_khz,
- clocksource_tsc.shift);
- if (check_tsc_unstable())
- clocksource_tsc.rating = 0;
-
- clocksource_register(&clocksource_tsc);
-}
diff --git a/include/asm-x86/apic.h b/include/asm-x86/apic.h
index 9fe941c..99c3cfb 100644
--- a/include/asm-x86/apic.h
+++ b/include/asm-x86/apic.h
@@ -125,12 +125,17 @@ extern void enable_NMI_through_LVT0(void);
*/
#ifdef CONFIG_X86_64
extern void early_init_lapic_mapping(void);
+extern int apic_is_clustered_box(void);
+#else
+static inline int apic_is_clustered_box(void)
+{
+ return 0;
+}
#endif
extern u8 setup_APIC_eilvt_mce(u8 vector, u8 msg_type, u8 mask);
extern u8 setup_APIC_eilvt_ibs(u8 vector, u8 msg_type, u8 mask);
-extern int apic_is_clustered_box(void);
#else /* !CONFIG_X86_LOCAL_APIC */
static inline void lapic_shutdown(void) { }
diff --git a/include/asm-x86/delay.h b/include/asm-x86/delay.h
index 409a649..bb80880 100644
--- a/include/asm-x86/delay.h
+++ b/include/asm-x86/delay.h
@@ -26,6 +26,10 @@ extern void __delay(unsigned long loops);
((n) > 20000 ? __bad_ndelay() : __const_udelay((n) * 5ul)) : \
__ndelay(n))
+#ifdef CONFIG_X86_32
void use_tsc_delay(void);
+#else
+#define use_tsc_delay() {}
+#endif
#endif /* _ASM_X86_DELAY_H */
diff --git a/include/asm-x86/time.h b/include/asm-x86/time.h
index bce72d7..a17fa47 100644
--- a/include/asm-x86/time.h
+++ b/include/asm-x86/time.h
@@ -56,4 +56,6 @@ static inline int native_set_wallclock(unsigned long nowtime)
#endif /* CONFIG_PARAVIRT */
+extern unsigned long __init calibrate_cpu(void);
+
#endif
diff --git a/include/asm-x86/tsc.h b/include/asm-x86/tsc.h
index 761054d..cb6f6ee 100644
--- a/include/asm-x86/tsc.h
+++ b/include/asm-x86/tsc.h
@@ -48,7 +48,6 @@ static __always_inline cycles_t vget_cycles(void)
extern void tsc_init(void);
extern void mark_tsc_unstable(char *reason);
extern int unsynchronized_tsc(void);
-extern void init_tsc_clocksource(void);
int check_tsc_unstable(void);
/*