Commit 99a49093 authored by Li RongQing's avatar Li RongQing Committed by Sean Christopherson
Browse files

KVM: SVM: Consider NUMA affinity when allocating per-CPU save_area 



save_area of per-CPU svm_data are dominantly accessed from their
own local CPUs, so allocate them node-local for performance reason

so rename __snp_safe_alloc_page as snp_safe_alloc_page_node which
accepts numa node id as input parameter, svm_cpu_init call it with
node id switched from cpu id

Signed-off-by: default avatarLi RongQing <lirongqing@baidu.com>
Reviewed-by: default avatarTom Lendacky <thomas.lendacky@amd.com>
Link: https://lore.kernel.org/r/20240520120858.13117-4-lirongqing@baidu.com


Signed-off-by: default avatarSean Christopherson <seanjc@google.com>
parent 9f44286d

arch/x86/kvm/svm/sev.c

+3 −3
Original line number Diff line number Diff line
@@ -3380,13 +3380,13 @@ void sev_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector) 
	}

}



struct page *__snp_safe_alloc_page(gfp_t gfp)

struct page *snp_safe_alloc_page_node(int node, gfp_t gfp)

{

	unsigned long pfn;

	struct page *p;



	if (!cc_platform_has(CC_ATTR_HOST_SEV_SNP))

		return alloc_page(gfp | __GFP_ZERO);

		return alloc_pages_node(node, gfp | __GFP_ZERO, 0);



	/*

	 * Allocate an SNP-safe page to workaround the SNP erratum where
@@ -3397,7 +3397,7 @@ struct page *__snp_safe_alloc_page(gfp_t gfp) 
	 * Allocate one extra page, choose a page which is not

	 * 2MB-aligned, and free the other.

	 */

	p = alloc_pages(gfp | __GFP_ZERO, 1);

	p = alloc_pages_node(node, gfp | __GFP_ZERO, 1);

	if (!p)

		return NULL;

arch/x86/kvm/svm/svm.c

+1 −1
Original line number Diff line number Diff line
@@ -703,7 +703,7 @@ static int svm_cpu_init(int cpu) 
	int ret = -ENOMEM;



	memset(sd, 0, sizeof(struct svm_cpu_data));

	sd->save_area = __snp_safe_alloc_page(GFP_KERNEL);

	sd->save_area = snp_safe_alloc_page_node(cpu_to_node(cpu), GFP_KERNEL);

	if (!sd->save_area)

		return ret;

arch/x86/kvm/svm/svm.h

+5 −5
Original line number Diff line number Diff line
@@ -694,11 +694,11 @@ void sev_guest_memory_reclaimed(struct kvm *kvm); 
int sev_handle_vmgexit(struct kvm_vcpu *vcpu);



/* These symbols are used in common code and are stubbed below.  */

struct page *__snp_safe_alloc_page(gfp_t gfp);



struct page *snp_safe_alloc_page_node(int node, gfp_t gfp);

static inline struct page *snp_safe_alloc_page(void)

{

	return __snp_safe_alloc_page(GFP_KERNEL_ACCOUNT);

	return snp_safe_alloc_page_node(numa_node_id(), GFP_KERNEL_ACCOUNT);

}



void sev_free_vcpu(struct kvm_vcpu *vcpu);
@@ -710,14 +710,14 @@ int sev_cpu_init(struct svm_cpu_data *sd); 
int sev_dev_get_attr(u32 group, u64 attr, u64 *val);

extern unsigned int max_sev_asid;

#else

static inline struct page *__snp_safe_alloc_page(gfp_t gfp)

static inline struct page *snp_safe_alloc_page_node(int node, gfp_t gfp)

{

	return alloc_page(gfp | __GFP_ZERO);

	return alloc_pages_node(node, gfp | __GFP_ZERO, 0);

}



static inline struct page *snp_safe_alloc_page(void)

{

	return __snp_safe_alloc_page(GFP_KERNEL_ACCOUNT);

	return snp_safe_alloc_page_node(numa_node_id(), GFP_KERNEL_ACCOUNT);

}



static inline void sev_free_vcpu(struct kvm_vcpu *vcpu) {}