[PATCH v3 2/2] arch/powerpc/kvm: kvmppc_hv_entry: remove r4 argument

From: Kautuk Consul
Date: Thu Mar 16 2023 - 01:11:05 EST


kvmppc_hv_entry is called from only 2 locations within
book3s_hv_rmhandlers.S. Both of those locations set r4
as HSTATE_KVM_VCPU(r13) before calling kvmppc_hv_entry.
So, shift the r4 load instruction to kvmppc_hv_entry and
thus modify the calling convention of this function.

Signed-off-by: Kautuk Consul <kconsul@xxxxxxxxxxxxxxxxxx>
---
arch/powerpc/kvm/book3s_hv_rmhandlers.S | 11 ++++++-----
1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kvm/book3s_hv_rmhandlers.S b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
index b81ba4ee0521..b61f0b2c677b 100644
--- a/arch/powerpc/kvm/book3s_hv_rmhandlers.S
+++ b/arch/powerpc/kvm/book3s_hv_rmhandlers.S
@@ -85,7 +85,7 @@ _GLOBAL_TOC(kvmppc_hv_entry_trampoline)
RFI_TO_KERNEL

kvmppc_call_hv_entry:
- ld r4, HSTATE_KVM_VCPU(r13)
+ /* Enter guest. */
bl kvmppc_hv_entry

/* Back from guest - restore host state and return to caller */
@@ -352,9 +352,7 @@ kvm_secondary_got_guest:
mtspr SPRN_LDBAR, r0
isync
63:
- /* Order load of vcpu after load of vcore */
- lwsync
- ld r4, HSTATE_KVM_VCPU(r13)
+ /* Enter guest. */
bl kvmppc_hv_entry

/* Back from the guest, go back to nap */
@@ -506,7 +504,6 @@ SYM_INNER_LABEL(kvmppc_hv_entry, SYM_L_LOCAL)

/* Required state:
*
- * R4 = vcpu pointer (or NULL)
* MSR = ~IR|DR
* R13 = PACA
* R1 = host R1
@@ -524,6 +521,10 @@ SYM_INNER_LABEL(kvmppc_hv_entry, SYM_L_LOCAL)
li r6, KVM_GUEST_MODE_HOST_HV
stb r6, HSTATE_IN_GUEST(r13)

+ /* Order load of vcpu after load of vcore */
+ lwsync
+ ld r4, HSTATE_KVM_VCPU(r13)
+
#ifdef CONFIG_KVM_BOOK3S_HV_P8_TIMING
/* Store initial timestamp */
cmpdi r4, 0
--
2.39.2