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Subject[PATCH 13/17] x86/tsc: Rename native_read_tsc() to rdtsc_unordered()
Date
Now that there is no paravirt TSC, the "native" is inappropriate.
The fact that rdtsc is not ordered can catch people by surprise, so
call it rdtsc_unordered().

Signed-off-by: Andy Lutomirski <luto@kernel.org>
---
arch/x86/boot/compressed/aslr.c | 2 +-
arch/x86/entry/vdso/vclock_gettime.c | 2 +-
arch/x86/include/asm/msr.h | 11 ++++++++++-
arch/x86/include/asm/pvclock.h | 2 +-
arch/x86/include/asm/stackprotector.h | 2 +-
arch/x86/include/asm/tsc.h | 2 +-
arch/x86/kernel/apb_timer.c | 8 ++++----
arch/x86/kernel/apic/apic.c | 8 ++++----
arch/x86/kernel/cpu/amd.c | 4 ++--
arch/x86/kernel/cpu/mcheck/mce.c | 4 ++--
arch/x86/kernel/espfix_64.c | 2 +-
arch/x86/kernel/hpet.c | 4 ++--
arch/x86/kernel/trace_clock.c | 2 +-
arch/x86/kernel/tsc.c | 4 ++--
arch/x86/kvm/lapic.c | 4 ++--
arch/x86/kvm/svm.c | 4 ++--
arch/x86/kvm/vmx.c | 4 ++--
arch/x86/kvm/x86.c | 12 ++++++------
arch/x86/lib/delay.c | 8 ++++----
drivers/input/gameport/gameport.c | 4 ++--
drivers/input/joystick/analog.c | 4 ++--
drivers/net/hamradio/baycom_epp.c | 2 +-
drivers/thermal/intel_powerclamp.c | 4 ++--
tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c | 4 ++--
24 files changed, 58 insertions(+), 49 deletions(-)

diff --git a/arch/x86/boot/compressed/aslr.c b/arch/x86/boot/compressed/aslr.c
index ea33236190b1..487a8a980da3 100644
--- a/arch/x86/boot/compressed/aslr.c
+++ b/arch/x86/boot/compressed/aslr.c
@@ -82,7 +82,7 @@ static unsigned long get_random_long(void)

if (has_cpuflag(X86_FEATURE_TSC)) {
debug_putstr(" RDTSC");
- raw = native_read_tsc();
+ raw = rdtsc_unordered();

random ^= raw;
use_i8254 = false;
diff --git a/arch/x86/entry/vdso/vclock_gettime.c b/arch/x86/entry/vdso/vclock_gettime.c
index 972b488ac16a..f9a0429875a7 100644
--- a/arch/x86/entry/vdso/vclock_gettime.c
+++ b/arch/x86/entry/vdso/vclock_gettime.c
@@ -186,7 +186,7 @@ notrace static cycle_t vread_tsc(void)
* but no one has ever seen it happen.
*/
rdtsc_barrier();
- ret = (cycle_t)native_read_tsc();
+ ret = (cycle_t)rdtsc_unordered();

last = gtod->cycle_last;

diff --git a/arch/x86/include/asm/msr.h b/arch/x86/include/asm/msr.h
index c89ed6ceed02..e04f36f65c95 100644
--- a/arch/x86/include/asm/msr.h
+++ b/arch/x86/include/asm/msr.h
@@ -109,7 +109,16 @@ notrace static inline int native_write_msr_safe(unsigned int msr,
extern int rdmsr_safe_regs(u32 regs[8]);
extern int wrmsr_safe_regs(u32 regs[8]);

-static __always_inline unsigned long long native_read_tsc(void)
+/**
+ * rdtsc_unordered() - returns the current TSC without ordering constraints
+ *
+ * rdtsc_unordered() returns the result of RDTSC as a 64-bit integer. The
+ * only ordering constraint it supplies is the ordering implied by
+ * "asm volatile": it will put the RDTSC in the place you expect. The
+ * CPU can and will speculatively execute that RDTSC, though, so the
+ * results can be non-monotonic if compared on different CPUs.
+ */
+static __always_inline unsigned long long rdtsc_unordered(void)
{
DECLARE_ARGS(val, low, high);

diff --git a/arch/x86/include/asm/pvclock.h b/arch/x86/include/asm/pvclock.h
index 71bd485c2986..cfd4e89c3acf 100644
--- a/arch/x86/include/asm/pvclock.h
+++ b/arch/x86/include/asm/pvclock.h
@@ -62,7 +62,7 @@ static inline u64 pvclock_scale_delta(u64 delta, u32 mul_frac, int shift)
static __always_inline
u64 pvclock_get_nsec_offset(const struct pvclock_vcpu_time_info *src)
{
- u64 delta = native_read_tsc() - src->tsc_timestamp;
+ u64 delta = rdtsc_unordered() - src->tsc_timestamp;
return pvclock_scale_delta(delta, src->tsc_to_system_mul,
src->tsc_shift);
}
diff --git a/arch/x86/include/asm/stackprotector.h b/arch/x86/include/asm/stackprotector.h
index bc5fa2af112e..11422aa255e6 100644
--- a/arch/x86/include/asm/stackprotector.h
+++ b/arch/x86/include/asm/stackprotector.h
@@ -72,7 +72,7 @@ static __always_inline void boot_init_stack_canary(void)
* on during the bootup the random pool has true entropy too.
*/
get_random_bytes(&canary, sizeof(canary));
- tsc = native_read_tsc();
+ tsc = rdtsc_unordered();
canary += tsc + (tsc << 32UL);

current->stack_canary = canary;
diff --git a/arch/x86/include/asm/tsc.h b/arch/x86/include/asm/tsc.h
index b4883902948b..6e10f8b2252e 100644
--- a/arch/x86/include/asm/tsc.h
+++ b/arch/x86/include/asm/tsc.h
@@ -26,7 +26,7 @@ static inline cycles_t get_cycles(void)
return 0;
#endif

- return native_read_tsc();
+ return rdtsc_unordered();
}

extern void tsc_init(void);
diff --git a/arch/x86/kernel/apb_timer.c b/arch/x86/kernel/apb_timer.c
index 25efa534c4e4..125d96b12141 100644
--- a/arch/x86/kernel/apb_timer.c
+++ b/arch/x86/kernel/apb_timer.c
@@ -263,7 +263,7 @@ static int apbt_clocksource_register(void)

/* Verify whether apbt counter works */
t1 = dw_apb_clocksource_read(clocksource_apbt);
- start = native_read_tsc();
+ start = rdtsc_unordered();

/*
* We don't know the TSC frequency yet, but waiting for
@@ -273,7 +273,7 @@ static int apbt_clocksource_register(void)
*/
do {
rep_nop();
- now = native_read_tsc();
+ now = rdtsc_unordered();
} while ((now - start) < 200000UL);

/* APBT is the only always on clocksource, it has to work! */
@@ -390,13 +390,13 @@ unsigned long apbt_quick_calibrate(void)
old = dw_apb_clocksource_read(clocksource_apbt);
old += loop;

- t1 = native_read_tsc();
+ t1 = rdtsc_unordered();

do {
new = dw_apb_clocksource_read(clocksource_apbt);
} while (new < old);

- t2 = native_read_tsc();
+ t2 = rdtsc_unordered();

shift = 5;
if (unlikely(loop >> shift == 0)) {
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 51af1ed1ae2e..b9a46bf64e24 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -457,7 +457,7 @@ static int lapic_next_deadline(unsigned long delta,
{
u64 tsc;

- tsc = native_read_tsc();
+ tsc = rdtsc_unordered();
wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
return 0;
}
@@ -592,7 +592,7 @@ static void __init lapic_cal_handler(struct clock_event_device *dev)
unsigned long pm = acpi_pm_read_early();

if (cpu_has_tsc)
- tsc = native_read_tsc();
+ tsc = rdtsc_unordered();

switch (lapic_cal_loops++) {
case 0:
@@ -1209,7 +1209,7 @@ void setup_local_APIC(void)
long long max_loops = cpu_khz ? cpu_khz : 1000000;

if (cpu_has_tsc)
- tsc = native_read_tsc();
+ tsc = rdtsc_unordered();

if (disable_apic) {
disable_ioapic_support();
@@ -1293,7 +1293,7 @@ void setup_local_APIC(void)
}
if (queued) {
if (cpu_has_tsc && cpu_khz) {
- ntsc = native_read_tsc();
+ ntsc = rdtsc_unordered();
max_loops = (cpu_khz << 10) - (ntsc - tsc);
} else
max_loops--;
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c
index c5ceec532799..196f2131f44d 100644
--- a/arch/x86/kernel/cpu/amd.c
+++ b/arch/x86/kernel/cpu/amd.c
@@ -118,10 +118,10 @@ static void init_amd_k6(struct cpuinfo_x86 *c)

n = K6_BUG_LOOP;
f_vide = vide;
- d = native_read_tsc();
+ d = rdtsc_unordered();
while (n--)
f_vide();
- d2 = native_read_tsc();
+ d2 = rdtsc_unordered();
d = d2-d;

if (d > 20*K6_BUG_LOOP)
diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index a5283d2d0094..e2c9311bf098 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -125,7 +125,7 @@ void mce_setup(struct mce *m)
{
memset(m, 0, sizeof(struct mce));
m->cpu = m->extcpu = smp_processor_id();
- m->tsc = native_read_tsc();
+ m->tsc = rdtsc_unordered();
/* We hope get_seconds stays lockless */
m->time = get_seconds();
m->cpuvendor = boot_cpu_data.x86_vendor;
@@ -1784,7 +1784,7 @@ static void collect_tscs(void *data)
{
unsigned long *cpu_tsc = (unsigned long *)data;

- cpu_tsc[smp_processor_id()] = native_read_tsc();
+ cpu_tsc[smp_processor_id()] = rdtsc_unordered();
}

static int mce_apei_read_done;
diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c
index 334a2a9c034d..e1d2f6839f49 100644
--- a/arch/x86/kernel/espfix_64.c
+++ b/arch/x86/kernel/espfix_64.c
@@ -110,7 +110,7 @@ static void init_espfix_random(void)
*/
if (!arch_get_random_long(&rand)) {
/* The constant is an arbitrary large prime */
- rand = native_read_tsc();
+ rand = rdtsc_unordered();
rand *= 0xc345c6b72fd16123UL;
}

diff --git a/arch/x86/kernel/hpet.c b/arch/x86/kernel/hpet.c
index ccf677cd9adc..141bba987f9b 100644
--- a/arch/x86/kernel/hpet.c
+++ b/arch/x86/kernel/hpet.c
@@ -734,7 +734,7 @@ static int hpet_clocksource_register(void)

/* Verify whether hpet counter works */
t1 = hpet_readl(HPET_COUNTER);
- start = native_read_tsc();
+ start = rdtsc_unordered();

/*
* We don't know the TSC frequency yet, but waiting for
@@ -744,7 +744,7 @@ static int hpet_clocksource_register(void)
*/
do {
rep_nop();
- now = native_read_tsc();
+ now = rdtsc_unordered();
} while ((now - start) < 200000UL);

if (t1 == hpet_readl(HPET_COUNTER)) {
diff --git a/arch/x86/kernel/trace_clock.c b/arch/x86/kernel/trace_clock.c
index bd8f4d41bd56..c0ab0bed02ae 100644
--- a/arch/x86/kernel/trace_clock.c
+++ b/arch/x86/kernel/trace_clock.c
@@ -15,7 +15,7 @@ u64 notrace trace_clock_x86_tsc(void)
u64 ret;

rdtsc_barrier();
- ret = native_read_tsc();
+ ret = rdtsc_unordered();

return ret;
}
diff --git a/arch/x86/kernel/tsc.c b/arch/x86/kernel/tsc.c
index e66f5dcaeb63..5eb4d91ce9db 100644
--- a/arch/x86/kernel/tsc.c
+++ b/arch/x86/kernel/tsc.c
@@ -248,7 +248,7 @@ static void set_cyc2ns_scale(unsigned long cpu_khz, int cpu)

data = cyc2ns_write_begin(cpu);

- tsc_now = native_read_tsc();
+ tsc_now = rdtsc_unordered();
ns_now = cycles_2_ns(tsc_now);

/*
@@ -290,7 +290,7 @@ u64 native_sched_clock(void)
}

/* read the Time Stamp Counter: */
- tsc_now = native_read_tsc();
+ tsc_now = rdtsc_unordered();

/* return the value in ns */
return cycles_2_ns(tsc_now);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 629af0f1c5c4..5b13eeea578a 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1148,7 +1148,7 @@ void wait_lapic_expire(struct kvm_vcpu *vcpu)

tsc_deadline = apic->lapic_timer.expired_tscdeadline;
apic->lapic_timer.expired_tscdeadline = 0;
- guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
+ guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, rdtsc_unordered());
trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline);

/* __delay is delay_tsc whenever the hardware has TSC, thus always. */
@@ -1216,7 +1216,7 @@ static void start_apic_timer(struct kvm_lapic *apic)
local_irq_save(flags);

now = apic->lapic_timer.timer.base->get_time();
- guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, native_read_tsc());
+ guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu, rdtsc_unordered());
if (likely(tscdeadline > guest_tsc)) {
ns = (tscdeadline - guest_tsc) * 1000000ULL;
do_div(ns, this_tsc_khz);
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 9afa233b5482..ec26eb38a768 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -1077,7 +1077,7 @@ static u64 svm_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
{
u64 tsc;

- tsc = svm_scale_tsc(vcpu, native_read_tsc());
+ tsc = svm_scale_tsc(vcpu, rdtsc_unordered());

return target_tsc - tsc;
}
@@ -3074,7 +3074,7 @@ static int svm_get_msr(struct kvm_vcpu *vcpu, unsigned ecx, u64 *data)
switch (ecx) {
case MSR_IA32_TSC: {
*data = svm->vmcb->control.tsc_offset +
- svm_scale_tsc(vcpu, native_read_tsc());
+ svm_scale_tsc(vcpu, rdtsc_unordered());

break;
}
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index fcff42100948..b220331bc575 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2236,7 +2236,7 @@ static u64 guest_read_tsc(void)
{
u64 host_tsc, tsc_offset;

- host_tsc = native_read_tsc();
+ host_tsc = rdtsc_unordered();
tsc_offset = vmcs_read64(TSC_OFFSET);
return host_tsc + tsc_offset;
}
@@ -2317,7 +2317,7 @@ static void vmx_adjust_tsc_offset(struct kvm_vcpu *vcpu, s64 adjustment, bool ho

static u64 vmx_compute_tsc_offset(struct kvm_vcpu *vcpu, u64 target_tsc)
{
- return target_tsc - native_read_tsc();
+ return target_tsc - rdtsc_unordered();
}

static bool guest_cpuid_has_vmx(struct kvm_vcpu *vcpu)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c26faf408bce..a9a3f31311e1 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1430,7 +1430,7 @@ static cycle_t read_tsc(void)
* but no one has ever seen it happen.
*/
rdtsc_barrier();
- ret = (cycle_t)native_read_tsc();
+ ret = (cycle_t)rdtsc_unordered();

last = pvclock_gtod_data.clock.cycle_last;

@@ -1621,7 +1621,7 @@ static int kvm_guest_time_update(struct kvm_vcpu *v)
return 1;
}
if (!use_master_clock) {
- host_tsc = native_read_tsc();
+ host_tsc = rdtsc_unordered();
kernel_ns = get_kernel_ns();
}

@@ -2945,7 +2945,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)

if (unlikely(vcpu->cpu != cpu) || check_tsc_unstable()) {
s64 tsc_delta = !vcpu->arch.last_host_tsc ? 0 :
- native_read_tsc() - vcpu->arch.last_host_tsc;
+ rdtsc_unordered() - vcpu->arch.last_host_tsc;
if (tsc_delta < 0)
mark_tsc_unstable("KVM discovered backwards TSC");
if (check_tsc_unstable()) {
@@ -2973,7 +2973,7 @@ void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
kvm_x86_ops->vcpu_put(vcpu);
kvm_put_guest_fpu(vcpu);
- vcpu->arch.last_host_tsc = native_read_tsc();
+ vcpu->arch.last_host_tsc = rdtsc_unordered();
}

static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
@@ -6388,7 +6388,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
hw_breakpoint_restore();

vcpu->arch.last_guest_tsc = kvm_x86_ops->read_l1_tsc(vcpu,
- native_read_tsc());
+ rdtsc_unordered());

vcpu->mode = OUTSIDE_GUEST_MODE;
smp_wmb();
@@ -7186,7 +7186,7 @@ int kvm_arch_hardware_enable(void)
if (ret != 0)
return ret;

- local_tsc = native_read_tsc();
+ local_tsc = rdtsc_unordered();
stable = !check_tsc_unstable();
list_for_each_entry(kvm, &vm_list, vm_list) {
kvm_for_each_vcpu(i, vcpu, kvm) {
diff --git a/arch/x86/lib/delay.c b/arch/x86/lib/delay.c
index 35115f3786a9..a524708fa165 100644
--- a/arch/x86/lib/delay.c
+++ b/arch/x86/lib/delay.c
@@ -55,10 +55,10 @@ static void delay_tsc(unsigned long __loops)
preempt_disable();
cpu = smp_processor_id();
rdtsc_barrier();
- bclock = native_read_tsc();
+ bclock = rdtsc_unordered();
for (;;) {
rdtsc_barrier();
- now = native_read_tsc();
+ now = rdtsc_unordered();
if ((now - bclock) >= loops)
break;

@@ -80,7 +80,7 @@ static void delay_tsc(unsigned long __loops)
loops -= (now - bclock);
cpu = smp_processor_id();
rdtsc_barrier();
- bclock = native_read_tsc();
+ bclock = rdtsc_unordered();
}
}
preempt_enable();
@@ -100,7 +100,7 @@ void use_tsc_delay(void)
int read_current_timer(unsigned long *timer_val)
{
if (delay_fn == delay_tsc) {
- *timer_val = native_read_tsc();
+ *timer_val = rdtsc_unordered();
return 0;
}
return -1;
diff --git a/drivers/input/gameport/gameport.c b/drivers/input/gameport/gameport.c
index abc0cb22e750..5671c3e35fb6 100644
--- a/drivers/input/gameport/gameport.c
+++ b/drivers/input/gameport/gameport.c
@@ -149,9 +149,9 @@ static int old_gameport_measure_speed(struct gameport *gameport)

for(i = 0; i < 50; i++) {
local_irq_save(flags);
- t1 = native_read_tsc();
+ t1 = rdtsc_unordered();
for (t = 0; t < 50; t++) gameport_read(gameport);
- t2 = native_read_tsc();
+ t2 = rdtsc_unordered();
local_irq_restore(flags);
udelay(i * 10);
if (t2 - t1 < tx) tx = t2 - t1;
diff --git a/drivers/input/joystick/analog.c b/drivers/input/joystick/analog.c
index f871b4f00056..3b251daa2092 100644
--- a/drivers/input/joystick/analog.c
+++ b/drivers/input/joystick/analog.c
@@ -143,7 +143,7 @@ struct analog_port {

#include <linux/i8253.h>

-#define GET_TIME(x) do { if (cpu_has_tsc) x = (unsigned int)native_read_tsc(); else x = get_time_pit(); } while (0)
+#define GET_TIME(x) do { if (cpu_has_tsc) x = (unsigned int)rdtsc_unordered(); else x = get_time_pit(); } while (0)
#define DELTA(x,y) (cpu_has_tsc ? ((y) - (x)) : ((x) - (y) + ((x) < (y) ? PIT_TICK_RATE / HZ : 0)))
#define TIME_NAME (cpu_has_tsc?"TSC":"PIT")
static unsigned int get_time_pit(void)
@@ -160,7 +160,7 @@ static unsigned int get_time_pit(void)
return count;
}
#elif defined(__x86_64__)
-#define GET_TIME(x) do { x = (unsigned int)native_read_tsc(); } while (0)
+#define GET_TIME(x) do { x = (unsigned int)rdtsc_unordered(); } while (0)
#define DELTA(x,y) ((y)-(x))
#define TIME_NAME "TSC"
#elif defined(__alpha__) || defined(CONFIG_MN10300) || defined(CONFIG_ARM) || defined(CONFIG_ARM64) || defined(CONFIG_TILE)
diff --git a/drivers/net/hamradio/baycom_epp.c b/drivers/net/hamradio/baycom_epp.c
index 44e5c3b5e0af..8302a54bb583 100644
--- a/drivers/net/hamradio/baycom_epp.c
+++ b/drivers/net/hamradio/baycom_epp.c
@@ -638,7 +638,7 @@ static int receive(struct net_device *dev, int cnt)
#define GETTICK(x) \
({ \
if (cpu_has_tsc) \
- x = (unsigned int)native_read_tsc(); \
+ x = (unsigned int)rdtsc_unordered(); \
})
#else /* __i386__ */
#define GETTICK(x)
diff --git a/drivers/thermal/intel_powerclamp.c b/drivers/thermal/intel_powerclamp.c
index 933c5e599d1d..ea6fd07739fd 100644
--- a/drivers/thermal/intel_powerclamp.c
+++ b/drivers/thermal/intel_powerclamp.c
@@ -340,7 +340,7 @@ static bool powerclamp_adjust_controls(unsigned int target_ratio,

/* check result for the last window */
msr_now = pkg_state_counter();
- tsc_now = native_read_tsc();
+ tsc_now = rdtsc_unordered();

/* calculate pkg cstate vs tsc ratio */
if (!msr_last || !tsc_last)
@@ -482,7 +482,7 @@ static void poll_pkg_cstate(struct work_struct *dummy)
u64 val64;

msr_now = pkg_state_counter();
- tsc_now = native_read_tsc();
+ tsc_now = rdtsc_unordered();
jiffies_now = jiffies;

/* calculate pkg cstate vs tsc ratio */
diff --git a/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c b/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c
index f02b0c0bff9b..511b7cb3a9c8 100644
--- a/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c
+++ b/tools/power/cpupower/debug/kernel/cpufreq-test_tsc.c
@@ -81,11 +81,11 @@ static int __init cpufreq_test_tsc(void)

printk(KERN_DEBUG "start--> \n");
then = read_pmtmr();
- then_tsc = native_read_tsc();
+ then_tsc = rdtsc_unordered();
for (i=0;i<20;i++) {
mdelay(100);
now = read_pmtmr();
- now_tsc = native_read_tsc();
+ now_tsc = rdtsc_unordered();
diff = (now - then) & 0xFFFFFF;
diff_tsc = now_tsc - then_tsc;
printk(KERN_DEBUG "t1: %08u t2: %08u diff_pmtmr: %08u diff_tsc: %016llu\n", then, now, diff, diff_tsc);
--
2.4.2


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