From: Oliver Upton <oliver.upton@linux.dev>
Date: Mon, 13 Feb 2023 23:26:21 +0000 (+0000)
Subject: Merge branch kvm-arm64/nv-timer-improvements into kvmarm/next
X-Git-Tag: v6.6.7~3413^2~2^2^2~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=1b915210d9bed44512f6034eacda9e8dcd89bd93;p=platform%2Fkernel%2Flinux-starfive.git

Merge branch kvm-arm64/nv-timer-improvements into kvmarm/next

* kvm-arm64/nv-timer-improvements:
  : Timer emulation improvements, courtesy of Marc Zyngier.
  :
  :  - Avoid re-arming an hrtimer for a guest timer that is already pending
  :
  :  - Only reload the affected timer context when emulating a sysreg access
  :    instead of both the virtual/physical timers.
  KVM: arm64: timers: Don't BUG() on unhandled timer trap
  KVM: arm64: Reduce overhead of trapped timer sysreg accesses
  KVM: arm64: Don't arm a hrtimer for an already pending timer

Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
---

1b915210d9bed44512f6034eacda9e8dcd89bd93
diff --cc arch/arm64/kvm/arch_timer.c
index 2334658,1a1d7e2..0061047
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@@ -975,15 -979,36 +987,24 @@@ void kvm_arm_timer_write_sysreg(struct 
  				enum kvm_arch_timer_regs treg,
  				u64 val)
  {
- 	preempt_disable();
- 	kvm_timer_vcpu_put(vcpu);
- 
- 	kvm_arm_timer_write(vcpu, vcpu_get_timer(vcpu, tmr), treg, val);
+ 	struct arch_timer_context *timer;
+ 	struct timer_map map;
  
- 	kvm_timer_vcpu_load(vcpu);
- 	preempt_enable();
+ 	get_timer_map(vcpu, &map);
+ 	timer = vcpu_get_timer(vcpu, tmr);
+ 	if (timer == map.emul_ptimer) {
+ 		soft_timer_cancel(&timer->hrtimer);
+ 		kvm_arm_timer_write(vcpu, timer, treg, val);
+ 		timer_emulate(timer);
+ 	} else {
+ 		preempt_disable();
+ 		timer_save_state(timer);
+ 		kvm_arm_timer_write(vcpu, timer, treg, val);
+ 		timer_restore_state(timer);
+ 		preempt_enable();
+ 	}
  }
  
 -static int kvm_timer_starting_cpu(unsigned int cpu)
 -{
 -	kvm_timer_init_interrupt(NULL);
 -	return 0;
 -}
 -
 -static int kvm_timer_dying_cpu(unsigned int cpu)
 -{
 -	disable_percpu_irq(host_vtimer_irq);
 -	return 0;
 -}
 -
  static int timer_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
  {
  	if (vcpu)