From: Gavin Shan <gshan@redhat.com>
To: kvmarm@lists.cs.columbia.edu
Cc: linux-kernel@vger.kernel.org, maz@kernel.org, will@kernel.org,
pbonzini@redhat.com, james.morse@arm.com, mark.rutland@arm.com,
Jonathan.Cameron@huawei.com, shan.gavin@gmail.com
Subject: [PATCH v3 12/15] arm64: Detect async PF para-virtualization feature
Date: Fri, 7 May 2021 16:40:50 +0800 [thread overview]
Message-ID: <20210507084053.44407-13-gshan@redhat.com> (raw)
In-Reply-To: <20210507084053.44407-1-gshan@redhat.com>
This implements kvm_para_available() to check if para-virtualization
features are available or not. Besides, kvm_para_has_feature() is
enhanced to detect the asynchronous page fault para-virtualization
feature. These two functions are going to be used by guest kernel
to enable the asynchronous page fault.
This also adds kernel option (CONFIG_KVM_GUEST), which is the umbrella
for the optimizations related to KVM para-virtualization.
Signed-off-by: Gavin Shan <gshan@redhat.com>
---
arch/arm64/Kconfig | 11 +++++++++++
arch/arm64/include/asm/kvm_para.h | 12 +++++++++++-
arch/arm64/include/uapi/asm/kvm_para.h | 2 ++
3 files changed, 24 insertions(+), 1 deletion(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 7f2a80091337..c03499c1acd6 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1104,6 +1104,17 @@ config PARAVIRT_TIME_ACCOUNTING
If in doubt, say N here.
+config KVM_GUEST
+ bool "KVM Guest Support"
+ depends on PARAVIRT
+ default y
+ help
+ This option enables various optimizations for running under the KVM
+ hypervisor. Overhead for the kernel when not running inside KVM should
+ be minimal.
+
+ In case of doubt, say Y
+
config KEXEC
depends on PM_SLEEP_SMP
select KEXEC_CORE
diff --git a/arch/arm64/include/asm/kvm_para.h b/arch/arm64/include/asm/kvm_para.h
index 0ea481dd1c7a..8f39c60a6619 100644
--- a/arch/arm64/include/asm/kvm_para.h
+++ b/arch/arm64/include/asm/kvm_para.h
@@ -3,6 +3,8 @@
#define _ASM_ARM_KVM_PARA_H
#include <uapi/asm/kvm_para.h>
+#include <linux/of.h>
+#include <asm/hypervisor.h>
static inline bool kvm_check_and_clear_guest_paused(void)
{
@@ -11,7 +13,12 @@ static inline bool kvm_check_and_clear_guest_paused(void)
static inline unsigned int kvm_arch_para_features(void)
{
- return 0;
+ unsigned int features = 0;
+
+ if (kvm_arm_hyp_service_available(ARM_SMCCC_KVM_FUNC_ASYNC_PF))
+ features |= (1 << KVM_FEATURE_ASYNC_PF);
+
+ return features;
}
static inline unsigned int kvm_arch_para_hints(void)
@@ -21,6 +28,9 @@ static inline unsigned int kvm_arch_para_hints(void)
static inline bool kvm_para_available(void)
{
+ if (IS_ENABLED(CONFIG_KVM_GUEST))
+ return true;
+
return false;
}
diff --git a/arch/arm64/include/uapi/asm/kvm_para.h b/arch/arm64/include/uapi/asm/kvm_para.h
index 162325e2638f..70bbc7d1ec75 100644
--- a/arch/arm64/include/uapi/asm/kvm_para.h
+++ b/arch/arm64/include/uapi/asm/kvm_para.h
@@ -4,6 +4,8 @@
#include <linux/types.h>
+#define KVM_FEATURE_ASYNC_PF 0
+
/* Async PF */
#define KVM_ASYNC_PF_ENABLED (1 << 0)
#define KVM_ASYNC_PF_SEND_ALWAYS (1 << 1)
--
2.23.0
next prev parent reply other threads:[~2021-05-07 6:41 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-07 8:40 [PATCH v3 00/15] Support Asynchronous Page Fault Gavin Shan
2021-05-07 8:40 ` [PATCH v3 01/15] KVM: async_pf: Move struct kvm_async_pf around Gavin Shan
2021-05-07 8:40 ` [PATCH v3 02/15] KVM: async_pf: Add helper function to check completion queue Gavin Shan
2021-05-07 8:40 ` [PATCH v3 03/15] KVM: async_pf: Make GFN slot management generic Gavin Shan
2021-05-07 8:40 ` [PATCH v3 04/15] KVM: x86: Use generic async PF slot management Gavin Shan
2021-05-07 8:40 ` [PATCH v3 05/15] KVM: arm64: Export kvm_handle_user_mem_abort() Gavin Shan
2021-05-07 8:40 ` [PATCH v3 06/15] KVM: arm64: Add paravirtualization header files Gavin Shan
2021-05-07 8:40 ` [PATCH v3 07/15] KVM: arm64: Support page-not-present notification Gavin Shan
2021-05-07 8:40 ` [PATCH v3 08/15] KVM: arm64: Support page-ready notification Gavin Shan
2021-05-07 8:40 ` [PATCH v3 09/15] KVM: arm64: Support async PF hypercalls Gavin Shan
2021-05-07 8:40 ` [PATCH v3 10/15] KVM: arm64: Support async PF ioctl commands Gavin Shan
2021-05-07 8:40 ` [PATCH v3 11/15] KVM: arm64: Export async PF capability Gavin Shan
2021-05-07 8:40 ` Gavin Shan [this message]
2021-05-07 8:40 ` [PATCH v3 13/15] arm64: Reschedule process on aync PF Gavin Shan
2021-05-07 8:40 ` [PATCH v3 14/15] arm64: Enable async PF Gavin Shan
2021-05-07 8:40 ` [PATCH v3 15/15] KVM: arm64: Add async PF document Gavin Shan
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