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authorMark Brown <broonie@kernel.org>2024-06-15 16:24:35 +0100
committerMark Brown <broonie@kernel.org>2024-06-15 16:24:35 +0100
commitc8d0930a047849cc816475b58656201e5a531adc (patch)
treec617af6cca234956921a042392b36181e1b85f2e /arch/x86/kvm/lapic.c
parent7fbc4f5e633cbc23576c32ff9773faa1788afc2d (diff)
parent432e5074f805d0f976c7430af376a0dd07f1c6d7 (diff)
ASoC: codecs: lpass: add support for v2.5 rx macro
Merge series from Srinivas Kandagatla <srinivas.kandagatla@linaro.org>: This patchset adds support to reading codec version and also adds support for v2.5 codec version in rx macro. LPASS 2.5 and up versions have changes in some of the rx blocks which are required to get headset functional correctly. Tested this on SM8450, X13s and x1e80100 crd. This changes also fixes issue with sm8450, sm8550, sm8660 and x1e80100.
Diffstat (limited to 'arch/x86/kvm/lapic.c')
-rw-r--r--arch/x86/kvm/lapic.c39
1 files changed, 21 insertions, 18 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index ebf41023be38..acd7d48100a1 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -59,7 +59,17 @@
#define MAX_APIC_VECTOR 256
#define APIC_VECTORS_PER_REG 32
-static bool lapic_timer_advance_dynamic __read_mostly;
+/*
+ * Enable local APIC timer advancement (tscdeadline mode only) with adaptive
+ * tuning. When enabled, KVM programs the host timer event to fire early, i.e.
+ * before the deadline expires, to account for the delay between taking the
+ * VM-Exit (to inject the guest event) and the subsequent VM-Enter to resume
+ * the guest, i.e. so that the interrupt arrives in the guest with minimal
+ * latency relative to the deadline programmed by the guest.
+ */
+static bool lapic_timer_advance __read_mostly = true;
+module_param(lapic_timer_advance, bool, 0444);
+
#define LAPIC_TIMER_ADVANCE_ADJUST_MIN 100 /* clock cycles */
#define LAPIC_TIMER_ADVANCE_ADJUST_MAX 10000 /* clock cycles */
#define LAPIC_TIMER_ADVANCE_NS_INIT 1000
@@ -1854,16 +1864,14 @@ static void __kvm_wait_lapic_expire(struct kvm_vcpu *vcpu)
guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
trace_kvm_wait_lapic_expire(vcpu->vcpu_id, guest_tsc - tsc_deadline);
- if (lapic_timer_advance_dynamic) {
- adjust_lapic_timer_advance(vcpu, guest_tsc - tsc_deadline);
- /*
- * If the timer fired early, reread the TSC to account for the
- * overhead of the above adjustment to avoid waiting longer
- * than is necessary.
- */
- if (guest_tsc < tsc_deadline)
- guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
- }
+ adjust_lapic_timer_advance(vcpu, guest_tsc - tsc_deadline);
+
+ /*
+ * If the timer fired early, reread the TSC to account for the overhead
+ * of the above adjustment to avoid waiting longer than is necessary.
+ */
+ if (guest_tsc < tsc_deadline)
+ guest_tsc = kvm_read_l1_tsc(vcpu, rdtsc());
if (guest_tsc < tsc_deadline)
__wait_lapic_expire(vcpu, tsc_deadline - guest_tsc);
@@ -2812,7 +2820,7 @@ static enum hrtimer_restart apic_timer_fn(struct hrtimer *data)
return HRTIMER_NORESTART;
}
-int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns)
+int kvm_create_lapic(struct kvm_vcpu *vcpu)
{
struct kvm_lapic *apic;
@@ -2845,13 +2853,8 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu, int timer_advance_ns)
hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
HRTIMER_MODE_ABS_HARD);
apic->lapic_timer.timer.function = apic_timer_fn;
- if (timer_advance_ns == -1) {
+ if (lapic_timer_advance)
apic->lapic_timer.timer_advance_ns = LAPIC_TIMER_ADVANCE_NS_INIT;
- lapic_timer_advance_dynamic = true;
- } else {
- apic->lapic_timer.timer_advance_ns = timer_advance_ns;
- lapic_timer_advance_dynamic = false;
- }
/*
* Stuff the APIC ENABLE bit in lieu of temporarily incrementing