[PATCH] arm64: kvm: Use has_vhe() instead of hyp_alternate_select()

From: Shanker Donthineni
Date: Sun Mar 05 2017 - 21:29:20 EST


Now all the cpu_hwcaps features have their own static keys. We don't
need a separate function hyp_alternate_select() to patch the vhe/nvhe
code. We can achieve the same functionality by using has_vhe(). It
improves the code readability, uses the jump label instructions, and
also compiler generates the better code with a fewer instructions.

Change-Id: Ia8084189833f2081ff13c392deb5070c46a64038
Signed-off-by: Shanker Donthineni <shankerd@xxxxxxxxxxxxxx>
---
arch/arm64/kvm/hyp/debug-sr.c | 12 ++++++----
arch/arm64/kvm/hyp/switch.c | 50 +++++++++++++++++++-----------------------
arch/arm64/kvm/hyp/sysreg-sr.c | 23 +++++++++----------
3 files changed, 43 insertions(+), 42 deletions(-)

diff --git a/arch/arm64/kvm/hyp/debug-sr.c b/arch/arm64/kvm/hyp/debug-sr.c
index f5154ed..e5642c2 100644
--- a/arch/arm64/kvm/hyp/debug-sr.c
+++ b/arch/arm64/kvm/hyp/debug-sr.c
@@ -109,9 +109,13 @@ static void __hyp_text __debug_save_spe_nvhe(u64 *pmscr_el1)
dsb(nsh);
}

-static hyp_alternate_select(__debug_save_spe,
- __debug_save_spe_nvhe, __debug_save_spe_vhe,
- ARM64_HAS_VIRT_HOST_EXTN);
+static void __hyp_text __debug_save_spe(u64 *pmscr_el1)
+{
+ if (has_vhe())
+ __debug_save_spe_vhe(pmscr_el1);
+ else
+ __debug_save_spe_nvhe(pmscr_el1);
+}

static void __hyp_text __debug_restore_spe(u64 pmscr_el1)
{
@@ -180,7 +184,7 @@ void __hyp_text __debug_cond_save_host_state(struct kvm_vcpu *vcpu)

__debug_save_state(vcpu, &vcpu->arch.host_debug_state.regs,
kern_hyp_va(vcpu->arch.host_cpu_context));
- __debug_save_spe()(&vcpu->arch.host_debug_state.pmscr_el1);
+ __debug_save_spe(&vcpu->arch.host_debug_state.pmscr_el1);
}

void __hyp_text __debug_cond_restore_host_state(struct kvm_vcpu *vcpu)
diff --git a/arch/arm64/kvm/hyp/switch.c b/arch/arm64/kvm/hyp/switch.c
index aede165..c5c77b8 100644
--- a/arch/arm64/kvm/hyp/switch.c
+++ b/arch/arm64/kvm/hyp/switch.c
@@ -33,13 +33,9 @@ static bool __hyp_text __fpsimd_enabled_vhe(void)
return !!(read_sysreg(cpacr_el1) & CPACR_EL1_FPEN);
}

-static hyp_alternate_select(__fpsimd_is_enabled,
- __fpsimd_enabled_nvhe, __fpsimd_enabled_vhe,
- ARM64_HAS_VIRT_HOST_EXTN);
-
bool __hyp_text __fpsimd_enabled(void)
{
- return __fpsimd_is_enabled()();
+ return has_vhe() ? __fpsimd_enabled_vhe() : __fpsimd_enabled_nvhe();
}

static void __hyp_text __activate_traps_vhe(void)
@@ -63,9 +59,10 @@ static void __hyp_text __activate_traps_nvhe(void)
write_sysreg(val, cptr_el2);
}

-static hyp_alternate_select(__activate_traps_arch,
- __activate_traps_nvhe, __activate_traps_vhe,
- ARM64_HAS_VIRT_HOST_EXTN);
+static void __hyp_text __activate_traps_arch(void)
+{
+ has_vhe() ? __activate_traps_vhe() : __activate_traps_nvhe();
+}

static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
{
@@ -97,7 +94,7 @@ static void __hyp_text __activate_traps(struct kvm_vcpu *vcpu)
write_sysreg(0, pmselr_el0);
write_sysreg(ARMV8_PMU_USERENR_MASK, pmuserenr_el0);
write_sysreg(vcpu->arch.mdcr_el2, mdcr_el2);
- __activate_traps_arch()();
+ __activate_traps_arch();
}

static void __hyp_text __deactivate_traps_vhe(void)
@@ -127,9 +124,10 @@ static void __hyp_text __deactivate_traps_nvhe(void)
write_sysreg(CPTR_EL2_DEFAULT, cptr_el2);
}

-static hyp_alternate_select(__deactivate_traps_arch,
- __deactivate_traps_nvhe, __deactivate_traps_vhe,
- ARM64_HAS_VIRT_HOST_EXTN);
+static void __hyp_text __deactivate_traps_arch(void)
+{
+ has_vhe() ? __deactivate_traps_vhe() : __deactivate_traps_nvhe();
+}

static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
{
@@ -142,7 +140,7 @@ static void __hyp_text __deactivate_traps(struct kvm_vcpu *vcpu)
if (vcpu->arch.hcr_el2 & HCR_VSE)
vcpu->arch.hcr_el2 = read_sysreg(hcr_el2);

- __deactivate_traps_arch()();
+ __deactivate_traps_arch();
write_sysreg(0, hstr_el2);
write_sysreg(0, pmuserenr_el0);
}
@@ -183,20 +181,14 @@ static void __hyp_text __vgic_restore_state(struct kvm_vcpu *vcpu)
__vgic_v2_restore_state(vcpu);
}

-static bool __hyp_text __true_value(void)
+static bool __check_arm_834220(void)
{
- return true;
-}
+ if (cpus_have_const_cap(ARM64_WORKAROUND_834220))
+ return true;

-static bool __hyp_text __false_value(void)
-{
return false;
}

-static hyp_alternate_select(__check_arm_834220,
- __false_value, __true_value,
- ARM64_WORKAROUND_834220);
-
static bool __hyp_text __translate_far_to_hpfar(u64 far, u64 *hpfar)
{
u64 par, tmp;
@@ -251,7 +243,7 @@ static bool __hyp_text __populate_fault_info(struct kvm_vcpu *vcpu)
* resolve the IPA using the AT instruction.
*/
if (!(esr & ESR_ELx_S1PTW) &&
- (__check_arm_834220()() || (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
+ (__check_arm_834220() || (esr & ESR_ELx_FSC_TYPE) == FSC_PERM)) {
if (!__translate_far_to_hpfar(far, &hpfar))
return false;
} else {
@@ -406,9 +398,13 @@ static void __hyp_text __hyp_call_panic_vhe(u64 spsr, u64 elr, u64 par)
(void *)read_sysreg(tpidr_el2));
}

-static hyp_alternate_select(__hyp_call_panic,
- __hyp_call_panic_nvhe, __hyp_call_panic_vhe,
- ARM64_HAS_VIRT_HOST_EXTN);
+static void __hyp_text __hyp_call_panic(u64 spsr, u64 elr, u64 par)
+{
+ if (has_vhe())
+ __hyp_call_panic_vhe(spsr, elr, par);
+ else
+ __hyp_call_panic_nvhe(spsr, elr, par);
+}

void __hyp_text __noreturn __hyp_panic(void)
{
@@ -428,7 +424,7 @@ void __hyp_text __noreturn __hyp_panic(void)
}

/* Call panic for real */
- __hyp_call_panic()(spsr, elr, par);
+ __hyp_call_panic(spsr, elr, par);

unreachable();
}
diff --git a/arch/arm64/kvm/hyp/sysreg-sr.c b/arch/arm64/kvm/hyp/sysreg-sr.c
index 9341376..2a6cb27 100644
--- a/arch/arm64/kvm/hyp/sysreg-sr.c
+++ b/arch/arm64/kvm/hyp/sysreg-sr.c
@@ -21,9 +21,6 @@
#include <asm/kvm_asm.h>
#include <asm/kvm_hyp.h>

-/* Yes, this does nothing, on purpose */
-static void __hyp_text __sysreg_do_nothing(struct kvm_cpu_context *ctxt) { }
-
/*
* Non-VHE: Both host and guest must save everything.
*
@@ -68,13 +65,15 @@ static void __hyp_text __sysreg_save_state(struct kvm_cpu_context *ctxt)
ctxt->gp_regs.spsr[KVM_SPSR_EL1]= read_sysreg_el1(spsr);
}

-static hyp_alternate_select(__sysreg_call_save_host_state,
- __sysreg_save_state, __sysreg_do_nothing,
- ARM64_HAS_VIRT_HOST_EXTN);
+static void __hyp_text __sysreg_call_save_host_state(struct kvm_cpu_context *ctxt)
+{
+ if (!has_vhe())
+ __sysreg_save_state(ctxt);
+}

void __hyp_text __sysreg_save_host_state(struct kvm_cpu_context *ctxt)
{
- __sysreg_call_save_host_state()(ctxt);
+ __sysreg_call_save_host_state(ctxt);
__sysreg_save_common_state(ctxt);
}

@@ -121,13 +120,15 @@ static void __hyp_text __sysreg_restore_state(struct kvm_cpu_context *ctxt)
write_sysreg_el1(ctxt->gp_regs.spsr[KVM_SPSR_EL1],spsr);
}

-static hyp_alternate_select(__sysreg_call_restore_host_state,
- __sysreg_restore_state, __sysreg_do_nothing,
- ARM64_HAS_VIRT_HOST_EXTN);
+static void __hyp_text __sysreg_call_restore_host_state(struct kvm_cpu_context *ctxt)
+{
+ if (!has_vhe())
+ __sysreg_restore_state(ctxt);
+}

void __hyp_text __sysreg_restore_host_state(struct kvm_cpu_context *ctxt)
{
- __sysreg_call_restore_host_state()(ctxt);
+ __sysreg_call_restore_host_state(ctxt);
__sysreg_restore_common_state(ctxt);
}

--
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