Commit 0d0ae656 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

KVM: arm64: timers: Use a per-vcpu, per-timer accumulator for fractional ns 



Instead of accumulating the fractional ns value generated every time
we compute a ns delta in a global variable, use a per-vcpu, per-timer
variable. This keeps the fractional ns local to the timer instead of
contributing to any odd, unrelated timer.

Reviewed-by: default avatarColton Lewis <coltonlewis@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-2-maz@kernel.org
parent e8d018dd

arch/arm64/kvm/arch_timer.c

+1 −1
Original line number Diff line number Diff line
@@ -212,7 +212,7 @@ static u64 kvm_counter_compute_delta(struct arch_timer_context *timer_ctx, 
		ns = cyclecounter_cyc2ns(timecounter->cc,

					 val - now,

					 timecounter->mask,

					 &timecounter->frac);

					 &timer_ctx->ns_frac);

		return ns;

	}

include/kvm/arm_arch_timer.h

+1 −0
Original line number Diff line number Diff line
@@ -44,6 +44,7 @@ struct arch_timer_context { 


	/* Emulated Timer (may be unused) */

	struct hrtimer			hrtimer;

	u64				ns_frac;



	/* Offset for this counter/timer */

	struct arch_timer_offset	offset;