X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Farch%2Fx86%2Fkernel%2Fapic%2Fapic.c;h=042e744eff11df12200b2bcf6969295eece5a679;hb=52f993b8e89487ec9ee15a7fb4979e0f09a45b27;hp=dcb52850a28fcbe00a4a25ddf47d6f4ccedf3c9c;hpb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;p=kvmfornfv.git

diff --git a/kernel/arch/x86/kernel/apic/apic.c b/kernel/arch/x86/kernel/apic/apic.c
index dcb52850a..042e744ef 100644
--- a/kernel/arch/x86/kernel/apic/apic.c
+++ b/kernel/arch/x86/kernel/apic/apic.c
@@ -305,7 +305,7 @@ int lapic_get_maxlvt(void)
 
 /* Clock divisor */
 #define APIC_DIVISOR 16
-#define TSC_DIVISOR  32
+#define TSC_DIVISOR  8
 
 /*
  * This function sets up the local APIC timer, with a timeout of
@@ -336,6 +336,13 @@ static void __setup_APIC_LVTT(unsigned int clocks, int oneshot, int irqen)
 	apic_write(APIC_LVTT, lvtt_value);
 
 	if (lvtt_value & APIC_LVT_TIMER_TSCDEADLINE) {
+		/*
+		 * See Intel SDM: TSC-Deadline Mode chapter. In xAPIC mode,
+		 * writing to the APIC LVTT and TSC_DEADLINE MSR isn't serialized.
+		 * According to Intel, MFENCE can do the serialization here.
+		 */
+		asm volatile("mfence" : : : "memory");
+
 		printk_once(KERN_DEBUG "TSC deadline timer enabled\n");
 		return;
 	}
@@ -457,45 +464,45 @@ static int lapic_next_deadline(unsigned long delta,
 {
 	u64 tsc;
 
-	rdtscll(tsc);
+	tsc = rdtsc();
 	wrmsrl(MSR_IA32_TSC_DEADLINE, tsc + (((u64) delta) * TSC_DIVISOR));
 	return 0;
 }
 
-/*
- * Setup the lapic timer in periodic or oneshot mode
- */
-static void lapic_timer_setup(enum clock_event_mode mode,
-			      struct clock_event_device *evt)
+static int lapic_timer_shutdown(struct clock_event_device *evt)
 {
-	unsigned long flags;
 	unsigned int v;
 
 	/* Lapic used as dummy for broadcast ? */
 	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
-		return;
+		return 0;
 
-	local_irq_save(flags);
+	v = apic_read(APIC_LVTT);
+	v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+	apic_write(APIC_LVTT, v);
+	apic_write(APIC_TMICT, 0);
+	return 0;
+}
 
-	switch (mode) {
-	case CLOCK_EVT_MODE_PERIODIC:
-	case CLOCK_EVT_MODE_ONESHOT:
-		__setup_APIC_LVTT(lapic_timer_frequency,
-				  mode != CLOCK_EVT_MODE_PERIODIC, 1);
-		break;
-	case CLOCK_EVT_MODE_UNUSED:
-	case CLOCK_EVT_MODE_SHUTDOWN:
-		v = apic_read(APIC_LVTT);
-		v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
-		apic_write(APIC_LVTT, v);
-		apic_write(APIC_TMICT, 0);
-		break;
-	case CLOCK_EVT_MODE_RESUME:
-		/* Nothing to do here */
-		break;
-	}
+static inline int
+lapic_timer_set_periodic_oneshot(struct clock_event_device *evt, bool oneshot)
+{
+	/* Lapic used as dummy for broadcast ? */
+	if (evt->features & CLOCK_EVT_FEAT_DUMMY)
+		return 0;
 
-	local_irq_restore(flags);
+	__setup_APIC_LVTT(lapic_timer_frequency, oneshot, 1);
+	return 0;
+}
+
+static int lapic_timer_set_periodic(struct clock_event_device *evt)
+{
+	return lapic_timer_set_periodic_oneshot(evt, false);
+}
+
+static int lapic_timer_set_oneshot(struct clock_event_device *evt)
+{
+	return lapic_timer_set_periodic_oneshot(evt, true);
 }
 
 /*
@@ -513,15 +520,18 @@ static void lapic_timer_broadcast(const struct cpumask *mask)
  * The local apic timer can be used for any function which is CPU local.
  */
 static struct clock_event_device lapic_clockevent = {
-	.name		= "lapic",
-	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT
-			| CLOCK_EVT_FEAT_C3STOP | CLOCK_EVT_FEAT_DUMMY,
-	.shift		= 32,
-	.set_mode	= lapic_timer_setup,
-	.set_next_event	= lapic_next_event,
-	.broadcast	= lapic_timer_broadcast,
-	.rating		= 100,
-	.irq		= -1,
+	.name			= "lapic",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP
+				  | CLOCK_EVT_FEAT_DUMMY,
+	.shift			= 32,
+	.set_state_shutdown	= lapic_timer_shutdown,
+	.set_state_periodic	= lapic_timer_set_periodic,
+	.set_state_oneshot	= lapic_timer_set_oneshot,
+	.set_next_event		= lapic_next_event,
+	.broadcast		= lapic_timer_broadcast,
+	.rating			= 100,
+	.irq			= -1,
 };
 static DEFINE_PER_CPU(struct clock_event_device, lapic_events);
 
@@ -547,12 +557,36 @@ static void setup_APIC_timer(void)
 				    CLOCK_EVT_FEAT_DUMMY);
 		levt->set_next_event = lapic_next_deadline;
 		clockevents_config_and_register(levt,
-						(tsc_khz / TSC_DIVISOR) * 1000,
+						tsc_khz * (1000 / TSC_DIVISOR),
 						0xF, ~0UL);
 	} else
 		clockevents_register_device(levt);
 }
 
+/*
+ * Install the updated TSC frequency from recalibration at the TSC
+ * deadline clockevent devices.
+ */
+static void __lapic_update_tsc_freq(void *info)
+{
+	struct clock_event_device *levt = this_cpu_ptr(&lapic_events);
+
+	if (!this_cpu_has(X86_FEATURE_TSC_DEADLINE_TIMER))
+		return;
+
+	clockevents_update_freq(levt, tsc_khz * (1000 / TSC_DIVISOR));
+}
+
+void lapic_update_tsc_freq(void)
+{
+	/*
+	 * The clockevent device's ->mult and ->shift can both be
+	 * changed. In order to avoid races, schedule the frequency
+	 * update code on each CPU.
+	 */
+	on_each_cpu(__lapic_update_tsc_freq, NULL, 0);
+}
+
 /*
  * In this functions we calibrate APIC bus clocks to the external timer.
  *
@@ -592,7 +626,7 @@ static void __init lapic_cal_handler(struct clock_event_device *dev)
 	unsigned long pm = acpi_pm_read_early();
 
 	if (cpu_has_tsc)
-		rdtscll(tsc);
+		tsc = rdtsc();
 
 	switch (lapic_cal_loops++) {
 	case 0:
@@ -778,7 +812,7 @@ static int __init calibrate_APIC_clock(void)
 		 * Setup the apic timer manually
 		 */
 		levt->event_handler = lapic_cal_handler;
-		lapic_timer_setup(CLOCK_EVT_MODE_PERIODIC, levt);
+		lapic_timer_set_periodic(levt);
 		lapic_cal_loops = -1;
 
 		/* Let the interrupts run */
@@ -788,7 +822,8 @@ static int __init calibrate_APIC_clock(void)
 			cpu_relax();
 
 		/* Stop the lapic timer */
-		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, levt);
+		local_irq_disable();
+		lapic_timer_shutdown(levt);
 
 		/* Jiffies delta */
 		deltaj = lapic_cal_j2 - lapic_cal_j1;
@@ -799,8 +834,8 @@ static int __init calibrate_APIC_clock(void)
 			apic_printk(APIC_VERBOSE, "... jiffies result ok\n");
 		else
 			levt->features |= CLOCK_EVT_FEAT_DUMMY;
-	} else
-		local_irq_enable();
+	}
+	local_irq_enable();
 
 	if (levt->features & CLOCK_EVT_FEAT_DUMMY) {
 		pr_warning("APIC timer disabled due to verification failure\n");
@@ -878,7 +913,7 @@ static void local_apic_timer_interrupt(void)
 	if (!evt->event_handler) {
 		pr_warning("Spurious LAPIC timer interrupt on cpu %d\n", cpu);
 		/* Switch it off */
-		lapic_timer_setup(CLOCK_EVT_MODE_SHUTDOWN, evt);
+		lapic_timer_shutdown(evt);
 		return;
 	}
 
@@ -1209,7 +1244,7 @@ void setup_local_APIC(void)
 	long long max_loops = cpu_khz ? cpu_khz : 1000000;
 
 	if (cpu_has_tsc)
-		rdtscll(tsc);
+		tsc = rdtsc();
 
 	if (disable_apic) {
 		disable_ioapic_support();
@@ -1293,7 +1328,7 @@ void setup_local_APIC(void)
 		}
 		if (queued) {
 			if (cpu_has_tsc && cpu_khz) {
-				rdtscll(ntsc);
+				ntsc = rdtsc();
 				max_loops = (cpu_khz << 10) - (ntsc - tsc);
 			} else
 				max_loops--;
@@ -1420,11 +1455,11 @@ enum {
 };
 static int x2apic_state;
 
-static inline void __x2apic_disable(void)
+static void __x2apic_disable(void)
 {
 	u64 msr;
 
-	if (cpu_has_apic)
+	if (!cpu_has_apic)
 		return;
 
 	rdmsrl(MSR_IA32_APICBASE, msr);
@@ -1436,7 +1471,7 @@ static inline void __x2apic_disable(void)
 	printk_once(KERN_INFO "x2apic disabled\n");
 }
 
-static inline void __x2apic_enable(void)
+static void __x2apic_enable(void)
 {
 	u64 msr;
 
@@ -1483,10 +1518,13 @@ void x2apic_setup(void)
 
 static __init void x2apic_disable(void)
 {
-	u32 x2apic_id;
+	u32 x2apic_id, state = x2apic_state;
 
-	if (x2apic_state != X2APIC_ON)
-		goto out;
+	x2apic_mode = 0;
+	x2apic_state = X2APIC_DISABLED;
+
+	if (state != X2APIC_ON)
+		return;
 
 	x2apic_id = read_apic_id();
 	if (x2apic_id >= 255)
@@ -1494,9 +1532,6 @@ static __init void x2apic_disable(void)
 
 	__x2apic_disable();
 	register_lapic_address(mp_lapic_addr);
-out:
-	x2apic_state = X2APIC_DISABLED;
-	x2apic_mode = 0;
 }
 
 static __init void x2apic_enable(void)
@@ -1576,6 +1611,9 @@ void __init enable_IR_x2apic(void)
 	unsigned long flags;
 	int ret, ir_stat;
 
+	if (skip_ioapic_setup)
+		return;
+
 	ir_stat = irq_remapping_prepare();
 	if (ir_stat < 0 && !x2apic_supported())
 		return;
@@ -1796,7 +1834,7 @@ int apic_version[MAX_LOCAL_APIC];
 /*
  * This interrupt should _never_ happen with our APIC/SMP architecture
  */
-static inline void __smp_spurious_interrupt(u8 vector)
+static void __smp_spurious_interrupt(u8 vector)
 {
 	u32 v;
 
@@ -1837,7 +1875,7 @@ __visible void smp_trace_spurious_interrupt(struct pt_regs *regs)
 /*
  * This interrupt should never happen with our APIC/SMP architecture
  */
-static inline void __smp_error_interrupt(struct pt_regs *regs)
+static void __smp_error_interrupt(struct pt_regs *regs)
 {
 	u32 v;
 	u32 i = 0;