git: 58eefc67a1cf - main - vmm vmx: Allocate vpids on demand as each vCPU is initialized.
Date: Fri, 18 Nov 2022 18:26:49 UTC
The branch main has been updated by jhb: URL: https://cgit.FreeBSD.org/src/commit/?id=58eefc67a1cf16623c23354efd089f65401c0455 commit 58eefc67a1cf16623c23354efd089f65401c0455 Author: John Baldwin <jhb@FreeBSD.org> AuthorDate: 2022-11-18 18:04:11 +0000 Commit: John Baldwin <jhb@FreeBSD.org> CommitDate: 2022-11-18 18:25:38 +0000 vmm vmx: Allocate vpids on demand as each vCPU is initialized. Compared to the previous version this does mean that if the system as a whole runs out of dedicated vPIDs you might end up with some vCPUs within a single VM using dedicated vPIDs and others using shared vPIDs, but this should not break anything. Reviewed by: corvink, markj Differential Revision: https://reviews.freebsd.org/D37169 --- sys/amd64/vmm/intel/vmx.c | 47 +++++++++++++++++------------------------------ sys/amd64/vmm/intel/vmx.h | 1 - 2 files changed, 17 insertions(+), 31 deletions(-) diff --git a/sys/amd64/vmm/intel/vmx.c b/sys/amd64/vmm/intel/vmx.c index 9db638fd858e..52573416ded7 100644 --- a/sys/amd64/vmm/intel/vmx.c +++ b/sys/amd64/vmm/intel/vmx.c @@ -527,36 +527,25 @@ vpid_free(int vpid) free_unr(vpid_unr, vpid); } -static void -vpid_alloc(uint16_t *vpid, int num) +static uint16_t +vpid_alloc(int vcpuid) { - int i, x; - - if (num <= 0 || num > VM_MAXCPU) - panic("invalid number of vpids requested: %d", num); + int x; /* * If the "enable vpid" execution control is not enabled then the * VPID is required to be 0 for all vcpus. */ - if ((procbased_ctls2 & PROCBASED2_ENABLE_VPID) == 0) { - for (i = 0; i < num; i++) - vpid[i] = 0; - return; - } + if ((procbased_ctls2 & PROCBASED2_ENABLE_VPID) == 0) + return (0); /* - * Allocate a unique VPID for each vcpu from the unit number allocator. + * Try to allocate a unique VPID for each from the unit number + * allocator. */ - for (i = 0; i < num; i++) { - x = alloc_unr(vpid_unr); - if (x == -1) - break; - else - vpid[i] = x; - } + x = alloc_unr(vpid_unr); - if (i < num) { + if (x == -1) { atomic_add_int(&vpid_alloc_failed, 1); /* @@ -570,12 +559,10 @@ vpid_alloc(uint16_t *vpid, int num) * It is still sub-optimal because the invvpid will invalidate * combined mappings for a particular VPID across all EP4TAs. */ - while (i-- > 0) - vpid_free(vpid[i]); - - for (i = 0; i < num; i++) - vpid[i] = i + 1; + return (vcpuid + 1); } + + return (x); } static void @@ -1035,7 +1022,6 @@ vmx_init(struct vm *vm, pmap_t pmap) { int error; struct vmx *vmx; - uint16_t maxcpus = vm_get_maxcpus(vm); vmx = malloc(sizeof(struct vmx), M_VMX, M_WAITOK | M_ZERO); vmx->vm = vm; @@ -1096,8 +1082,6 @@ vmx_init(struct vm *vm, pmap_t pmap) ((cap_rdpid || cap_rdtscp) && guest_msr_ro(vmx, MSR_TSC_AUX))) panic("vmx_init: error setting guest msr access"); - vpid_alloc(vmx->vpids, maxcpus); - if (virtual_interrupt_delivery) { error = vm_map_mmio(vm, DEFAULT_APIC_BASE, PAGE_SIZE, APIC_ACCESS_ADDRESS); @@ -1116,8 +1100,11 @@ vmx_vcpu_init(void *vmi, struct vcpu *vcpu1, int vcpuid) struct vmcs *vmcs; struct vmx_vcpu *vcpu; uint32_t exc_bitmap; + uint16_t vpid; int error; + vpid = vpid_alloc(vcpuid); + vcpu = malloc(sizeof(*vcpu), M_VMX, M_WAITOK | M_ZERO); vcpu->vmx = vmx; vcpu->vcpu = vcpu1; @@ -1156,7 +1143,7 @@ vmx_vcpu_init(void *vmi, struct vcpu *vcpu1, int vcpuid) error += vmwrite(VMCS_EXIT_CTLS, exit_ctls); error += vmwrite(VMCS_ENTRY_CTLS, entry_ctls); error += vmwrite(VMCS_MSR_BITMAP, vtophys(vmx->msr_bitmap)); - error += vmwrite(VMCS_VPID, vmx->vpids[vcpuid]); + error += vmwrite(VMCS_VPID, vpid); if (guest_l1d_flush && !guest_l1d_flush_sw) { vmcs_write(VMCS_ENTRY_MSR_LOAD, pmap_kextract( @@ -1204,7 +1191,7 @@ vmx_vcpu_init(void *vmi, struct vcpu *vcpu1, int vcpuid) vcpu->state.nextrip = ~0; vcpu->state.lastcpu = NOCPU; - vcpu->state.vpid = vmx->vpids[vcpuid]; + vcpu->state.vpid = vpid; /* * Set up the CR0/4 shadows, and init the read shadow diff --git a/sys/amd64/vmm/intel/vmx.h b/sys/amd64/vmm/intel/vmx.h index e91675b62800..ad172073b03f 100644 --- a/sys/amd64/vmm/intel/vmx.h +++ b/sys/amd64/vmm/intel/vmx.h @@ -147,7 +147,6 @@ struct vmx { uint64_t eptp; long eptgen[MAXCPU]; /* cached pmap->pm_eptgen */ pmap_t pmap; - uint16_t vpids[VM_MAXCPU]; }; extern bool vmx_have_msr_tsc_aux;