[PATCH 03/13] KVM: arm64: Replace timer context vcpu pointer with timer_id

Marc Zyngier
2025-09-29T16:05:06Z

Having to follow a pointer to a vcpu is pretty dumb, when the timers
are are a fixed offset in the vcpu structure itself.

Trade the vcpu pointer for a timer_id, which can then be used to
compute the vcpu address as needed.

Signed-off-by: Marc Zyngier <maz@kernel.org>
---
arch/arm64/kvm/arch_timer.c | 4 ++--
include/kvm/arm_arch_timer.h | 11 ++++++-----
2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/kvm/arch_timer.c b/arch/arm64/kvm/arch_timer.c
index e5a25e743f5be..c832c293676a3 100644
--- a/arch/arm64/kvm/arch_timer.c
+++ b/arch/arm64/kvm/arch_timer.c
@@ -149,7 +149,7 @@ static void timer_set_cval(struct arch_timer_context *ctxt, u64 cval)
static void timer_set_offset(struct arch_timer_context *ctxt, u64 offset)
{
if (!ctxt->offset.vm_offset) {
- WARN(offset, "timer %ld\n", arch_timer_ctx_index(ctxt));
+ WARN(offset, "timer %d\n", arch_timer_ctx_index(ctxt));
return;
}

@@ -1064,7 +1064,7 @@ static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
struct arch_timer_context *ctxt = vcpu_get_timer(vcpu, timerid);
struct kvm *kvm = vcpu->kvm;

- ctxt->vcpu = vcpu;
+ ctxt->timer_id = timerid;

if (timerid == TIMER_VTIMER)
ctxt->offset.vm_offset = &kvm->arch.timer_data.voffset;
diff --git a/include/kvm/arm_arch_timer.h b/include/kvm/arm_arch_timer.h
index d188c716d03cb..d8e400cb2bfff 100644
--- a/include/kvm/arm_arch_timer.h
+++ b/include/kvm/arm_arch_timer.h
@@ -51,8 +51,6 @@ struct arch_timer_vm_data {
};

struct arch_timer_context {
- struct kvm_vcpu *vcpu;
-
/* Emulated Timer (may be unused) */
struct hrtimer hrtimer;
u64 ns_frac;
@@ -71,6 +69,9 @@ struct arch_timer_context {
bool level;
} irq;

+ /* Who am I? */
+ enum kvm_arch_timers timer_id;
+
/* Duplicated state from arch_timer.c for convenience */
u32 host_timer_irq;
};
@@ -127,9 +128,9 @@ void kvm_timer_init_vhe(void);
#define vcpu_hvtimer(v) (&(v)->arch.timer_cpu.timers[TIMER_HVTIMER])
#define vcpu_hptimer(v) (&(v)->arch.timer_cpu.timers[TIMER_HPTIMER])

-#define arch_timer_ctx_index(ctx) ((ctx) - vcpu_timer((ctx)->vcpu)->timers)
-#define timer_context_to_vcpu(ctx) ((ctx)->vcpu)
-#define timer_vm_data(ctx) (&(ctx)->vcpu->kvm->arch.timer_data)
+#define arch_timer_ctx_index(ctx) ((ctx)->timer_id)
+#define timer_context_to_vcpu(ctx) container_of((ctx), struct kvm_vcpu, arch.timer_cpu.timers[(ctx)->timer_id])
+#define timer_vm_data(ctx) (&(timer_context_to_vcpu(ctx)->kvm->arch.timer_data))
#define timer_irq(ctx) (timer_vm_data(ctx)->ppi[arch_timer_ctx_index(ctx)])

u64 kvm_arm_timer_read_sysreg(struct kvm_vcpu *vcpu,
--
2.47.3