From: Mark Rutland <mark.rutland@arm.com>
To: linux-arm-kernel@lists.infradead.org
Cc: marc.zyngier@arm.com, andre.przywara@arm.com,
will.deacon@arm.com, dave.martin@arm.com,
catalin.marinas@arm.com, kvmarm@lists.cs.columbia.edu
Subject: [PATCH 3/3] arm64/kvm: use alternative auto-nop
Date: Wed, 7 Sep 2016 11:07:10 +0100 [thread overview]
Message-ID: <1473242830-26246-4-git-send-email-mark.rutland@arm.com> (raw)
In-Reply-To: <1473242830-26246-1-git-send-email-mark.rutland@arm.com>
Make use of the new alternative_if and alternative_else_nop_endif and
get rid of our homebew NOP sleds, making the code simpler to read.
Note that for __kvm_call_hyp the branch to __vhe_hyp_call has been moved
out of the alternative sequence, and in the default case there will be
four additional NOPs executed.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: kvmarm@lists.cs.columbia.edu
---
arch/arm64/include/asm/kvm_mmu.h | 10 +++-------
arch/arm64/kvm/hyp.S | 6 +-----
2 files changed, 4 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index b6bb834..dff1098 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -99,14 +99,10 @@
.macro kern_hyp_va reg
alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
and \reg, \reg, #HYP_PAGE_OFFSET_HIGH_MASK
-alternative_else
- nop
-alternative_endif
-alternative_if_not ARM64_HYP_OFFSET_LOW
- nop
-alternative_else
+alternative_else_nop_endif
+alternative_if ARM64_HYP_OFFSET_LOW
and \reg, \reg, #HYP_PAGE_OFFSET_LOW_MASK
-alternative_endif
+alternative_else_nop_endif
.endm
#else
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index 7ce9315..2726635 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -46,10 +46,6 @@ alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
hvc #0
ldr lr, [sp], #16
ret
-alternative_else
+alternative_else_nop_endif
b __vhe_hyp_call
- nop
- nop
- nop
-alternative_endif
ENDPROC(__kvm_call_hyp)
--
1.9.1
WARNING: multiple messages have this Message-ID (diff)
From: mark.rutland@arm.com (Mark Rutland)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH 3/3] arm64/kvm: use alternative auto-nop
Date: Wed, 7 Sep 2016 11:07:10 +0100 [thread overview]
Message-ID: <1473242830-26246-4-git-send-email-mark.rutland@arm.com> (raw)
In-Reply-To: <1473242830-26246-1-git-send-email-mark.rutland@arm.com>
Make use of the new alternative_if and alternative_else_nop_endif and
get rid of our homebew NOP sleds, making the code simpler to read.
Note that for __kvm_call_hyp the branch to __vhe_hyp_call has been moved
out of the alternative sequence, and in the default case there will be
four additional NOPs executed.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Christoffer Dall <christoffer.dall@linaro.org>
Cc: kvmarm at lists.cs.columbia.edu
---
arch/arm64/include/asm/kvm_mmu.h | 10 +++-------
arch/arm64/kvm/hyp.S | 6 +-----
2 files changed, 4 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h
index b6bb834..dff1098 100644
--- a/arch/arm64/include/asm/kvm_mmu.h
+++ b/arch/arm64/include/asm/kvm_mmu.h
@@ -99,14 +99,10 @@
.macro kern_hyp_va reg
alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
and \reg, \reg, #HYP_PAGE_OFFSET_HIGH_MASK
-alternative_else
- nop
-alternative_endif
-alternative_if_not ARM64_HYP_OFFSET_LOW
- nop
-alternative_else
+alternative_else_nop_endif
+alternative_if ARM64_HYP_OFFSET_LOW
and \reg, \reg, #HYP_PAGE_OFFSET_LOW_MASK
-alternative_endif
+alternative_else_nop_endif
.endm
#else
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index 7ce9315..2726635 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -46,10 +46,6 @@ alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
hvc #0
ldr lr, [sp], #16
ret
-alternative_else
+alternative_else_nop_endif
b __vhe_hyp_call
- nop
- nop
- nop
-alternative_endif
ENDPROC(__kvm_call_hyp)
--
1.9.1
next prev parent reply other threads:[~2016-09-07 9:59 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-09-07 10:07 [PATCH 0/3] arm64: alternative: add auto-nop support Mark Rutland
2016-09-07 10:07 ` Mark Rutland
2016-09-07 10:07 ` [PATCH 1/3] arm64: alternative: add auto-nop infrastructure Mark Rutland
2016-09-07 10:07 ` Mark Rutland
2016-09-13 8:36 ` Ard Biesheuvel
2016-09-13 8:36 ` Ard Biesheuvel
2016-09-13 8:57 ` Mark Rutland
2016-09-13 8:57 ` Mark Rutland
2016-09-13 8:59 ` Ard Biesheuvel
2016-09-13 8:59 ` Ard Biesheuvel
2016-09-07 10:07 ` [PATCH 2/3] arm64: use alternative auto-nop Mark Rutland
2016-09-07 10:07 ` Mark Rutland
2016-09-07 10:07 ` Mark Rutland [this message]
2016-09-07 10:07 ` [PATCH 3/3] arm64/kvm: " Mark Rutland
2016-09-08 11:16 ` Christoffer Dall
2016-09-08 11:16 ` Christoffer Dall
2016-09-08 11:33 ` Mark Rutland
2016-09-08 11:33 ` Mark Rutland
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