From e9986b0dd66608af54d03b1dc9facc80b162dbaa Mon Sep 17 00:00:00 2001 From: Andrew Cooper Date: Wed, 27 Mar 2019 18:50:46 +0000 Subject: [PATCH] x86/vvmx: Simplify per-CPU memory allocations * Use XFREE() instead of opencoding it in nvmx_cpu_dead() * Avoid redundant evaluations of per_cpu() * Don't allocate vvmcs_buf at all if it isn't going to be used. It is never touched on hardware lacking the VMCS Shadowing feature. Signed-off-by: Andrew Cooper Reviewed-by: Wei Liu Acked-by: Kevin Tian --- xen/arch/x86/hvm/vmx/vvmx.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/xen/arch/x86/hvm/vmx/vvmx.c b/xen/arch/x86/hvm/vmx/vvmx.c index 991445e476..7bca572d88 100644 --- a/xen/arch/x86/hvm/vmx/vvmx.c +++ b/xen/arch/x86/hvm/vmx/vvmx.c @@ -40,21 +40,25 @@ static bool nvmx_vcpu_in_vmx(const struct vcpu *v) int nvmx_cpu_up_prepare(unsigned int cpu) { - if ( per_cpu(vvmcs_buf, cpu) != NULL ) - return 0; + uint64_t **vvmcs_buf; - per_cpu(vvmcs_buf, cpu) = xzalloc_array(u64, VMCS_BUF_SIZE); + if ( cpu_has_vmx_vmcs_shadowing && + (vvmcs_buf = &per_cpu(vvmcs_buf, cpu)) == NULL ) + { + void *ptr = xzalloc_array(uint64_t, VMCS_BUF_SIZE); - if ( per_cpu(vvmcs_buf, cpu) != NULL ) - return 0; + if ( !ptr ) + return -ENOMEM; - return -ENOMEM; + *vvmcs_buf = ptr; + } + + return 0; } void nvmx_cpu_dead(unsigned int cpu) { - xfree(per_cpu(vvmcs_buf, cpu)); - per_cpu(vvmcs_buf, cpu) = NULL; + XFREE(per_cpu(vvmcs_buf, cpu)); } int nvmx_vcpu_initialise(struct vcpu *v) -- 2.30.2