diff mbox series

[RFC,02/43] KMV: PPC: Book3S HV P9: Use set_dec to set decrementer to host

Message ID 20210622105736.633352-3-npiggin@gmail.com
State New
Headers show
Series KVM: PPC: Book3S HV P9: entry/exit optimisations round 1 | expand

Commit Message

Nicholas Piggin June 22, 2021, 10:56 a.m. UTC 
The host Linux timer code arms the decrementer with the value
'decrementers_next_tb - current_tb' using set_dec(), which stores
val - 1 on Book3S-64, which is not quite the same as what KVM does
to re-arm the host decrementer when exiting the guest.

This shouldn't be a significant change, but it makes the logic match
and avoids this small extra change being brought into the next patch.

Suggested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
---
 arch/powerpc/kvm/book3s_hv.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 97f3d6d54b61..d19b4ae01642 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -3914,7 +3914,7 @@  static int kvmhv_p9_guest_entry(struct kvm_vcpu *vcpu, u64 time_limit,
 	vc->entry_exit_map = 0x101;
 	vc->in_guest = 0;
 
-	mtspr(SPRN_DEC, local_paca->kvm_hstate.dec_expires - mftb());
+	set_dec(local_paca->kvm_hstate.dec_expires - mftb());
 	/* We may have raced with new irq work */
 	if (test_irq_work_pending())
 		set_dec(1);