Woops. Forgot to include my edits. Please ignore. I'll send out another
version shortly.
Thanks,
Marc
On Mon, May 14, 2018 at 11:55 AM Marc Orr <marcorr@xxxxxxxxxx> wrote:
> The kvm struct has been bloating. For example, it's tens of kilo-bytes
> for x86, which turns out to be a large amount of memory to allocate
> contiguously via kzalloc. Thus, this patch does the following:
> 1. Uses architecture-specific routines to allocat the kvm struct via
> kzalloc for x86 and also for arm when has_tbe() is true.
> 2. Introduces a baseline allocator for the kvm struct that uses valloc.
> This allocator can be used by an architecture by defining the
> __KVM_VALLOC_ARCH_VM macro before including include/linux/kvm_host.h.
> 3. Finally, continue to default to kalloc for all other situations, as
> many architectures have taken a dependence on kalloc.
> Signed-off-by: Marc Orr <marcorr@xxxxxxxxxx>
> ---
> arch/arm/include/asm/kvm_host.h | 4 ++++
> arch/arm/kvm/guest.c | 10 ++++++++++
> arch/arm64/include/asm/kvm_host.h | 4 ++++
> arch/arm64/kvm/guest.c | 10 ++++++++++
> arch/x86/kvm/svm.c | 4 ++--
> arch/x86/kvm/vmx.c | 4 ++--
> include/linux/kvm_host.h | 5 +++--
> 7 files changed, 35 insertions(+), 6 deletions(-)
> diff --git a/arch/arm/include/asm/kvm_host.h
b/arch/arm/include/asm/kvm_host.h
> index c7c28c885a19..f38fd60b4d4d 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -318,4 +318,8 @@ static inline bool
kvm_arm_harden_branch_predictor(void)
> static inline void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu) {}
> static inline void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu) {}
> +#define __KVM_HAVE_ARCH_VM_ALLOC
> +struct kvm *kvm_arch_alloc_vm(void);
> +void kvm_arch_free_vm(struct kvm *kvm);
> +
> #endif /* __ARM_KVM_HOST_H__ */
> diff --git a/arch/arm/kvm/guest.c b/arch/arm/kvm/guest.c
> index a18f33edc471..e0e9aa6e333b 100644
> --- a/arch/arm/kvm/guest.c
> +++ b/arch/arm/kvm/guest.c
> @@ -42,6 +42,16 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
> { NULL }
> };
> +struct kvm *kvm_arch_alloc_vm(void)
> +{
> + return kzalloc(sizeof(struct kvm), GFP_KERNEL);
> +}
> +
> +void kvm_arch_free_vm(struct kvm *kvm)
> +{
> + kfree(kvm);
> +}
> +
> int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
> {
> return 0;
> diff --git a/arch/arm64/include/asm/kvm_host.h
b/arch/arm64/include/asm/kvm_host.h
> index 469de8acd06f..358b1b4dcd92 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -455,4 +455,8 @@ static inline bool
kvm_arm_harden_branch_predictor(void)
> void kvm_vcpu_load_sysregs(struct kvm_vcpu *vcpu);
> void kvm_vcpu_put_sysregs(struct kvm_vcpu *vcpu);
> +#define __KVM_HAVE_ARCH_VM_ALLOC
> +struct kvm *kvm_arch_alloc_vm(void);
> +void kvm_arch_free_vm(struct kvm *kvm);
> +
> #endif /* __ARM64_KVM_HOST_H__ */
> diff --git a/arch/arm64/kvm/guest.c b/arch/arm64/kvm/guest.c
> index 56a0260ceb11..7a788e1f5cf3 100644
> --- a/arch/arm64/kvm/guest.c
> +++ b/arch/arm64/kvm/guest.c
> @@ -47,6 +47,16 @@ struct kvm_stats_debugfs_item debugfs_entries[] = {
> { NULL }
> };
> +struct kvm *kvm_arch_alloc_vm(void)
> +{
> + return kzalloc(sizeof(struct kvm), GFP_KERNEL);
> +}
> +
> +void kvm_arch_free_vm(struct kvm *kvm)
> +{
> + kfree(kvm);
> +}
> +
> int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
> {
> return 0;
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index 1fc05e428aba..45b903ed3e5d 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -1849,13 +1849,13 @@ static void __unregister_enc_region_locked(struct
kvm *kvm,
> static struct kvm *svm_vm_alloc(void)
> {
> - struct kvm_svm *kvm_svm = kzalloc(sizeof(struct kvm_svm),
GFP_KERNEL);
> + struct kvm_svm *kvm_svm = vzalloc(sizeof(struct kvm_svm));
> return &kvm_svm->kvm;
> }
> static void svm_vm_free(struct kvm *kvm)
> {
> - kfree(to_kvm_svm(kvm));
> + vfree(to_kvm_svm(kvm));
> }
> static void sev_vm_destroy(struct kvm *kvm)
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 3f1696570b41..ee85ba887db6 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -9936,13 +9936,13 @@ STACK_FRAME_NON_STANDARD(vmx_vcpu_run);
> static struct kvm *vmx_vm_alloc(void)
> {
> - struct kvm_vmx *kvm_vmx = kzalloc(sizeof(struct kvm_vmx),
GFP_KERNEL);
> + struct kvm_vmx *kvm_vmx = vzalloc(sizeof(struct kvm_vmx));
> return &kvm_vmx->kvm;
> }
> static void vmx_vm_free(struct kvm *kvm)
> {
> - kfree(to_kvm_vmx(kvm));
> + vfree(to_kvm_vmx(kvm));
> }
> static void vmx_switch_vmcs(struct kvm_vcpu *vcpu, struct loaded_vmcs
*vmcs)
> diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
> index 6d6e79c59e68..ffdc29d8505e 100644
> --- a/include/linux/kvm_host.h
> +++ b/include/linux/kvm_host.h
> @@ -19,6 +19,7 @@
> #include <linux/preempt.h>
> #include <linux/msi.h>
> #include <linux/slab.h>
> +#include <linux/vmalloc.h>
> #include <linux/rcupdate.h>
> #include <linux/ratelimit.h>
> #include <linux/err.h>
> @@ -810,12 +811,12 @@ int kvm_arch_vcpu_should_kick(struct kvm_vcpu
*vcpu);
> #ifndef __KVM_HAVE_ARCH_VM_ALLOC
> static inline struct kvm *kvm_arch_alloc_vm(void)
> {
> - return kzalloc(sizeof(struct kvm), GFP_KERNEL);
> + return vzalloc(sizeof(struct kvm));
> }
> static inline void kvm_arch_free_vm(struct kvm *kvm)
> {
> - kfree(kvm);
> + vfree(kvm);
> }
> #endif
> --
> 2.17.0.441.gb46fe60e1d-goog
