[src/trunk]: src/sys/dev/nvmm/x86 Optimize: the hardware does not clear the T...

[maxv <maxv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/50770bc063f5
branches:  trunk
changeset: 448879:50770bc063f5
user:      maxv <maxv%NetBSD.org@localhost>
date:      Tue Feb 12 14:54:59 2019 +0000

description:
Optimize: the hardware does not clear the TLB flush command after a
VMENTRY, so clear it ourselves, to avoid uselessly flushing the guest
TLB. While here also fix the processing of EFER-induced flushes, they
shouldn't be delayed.

diffstat:

 sys/dev/nvmm/x86/nvmm_x86_svm.c |  21 ++++++++++-----------
 1 files changed, 10 insertions(+), 11 deletions(-)

diffs (56 lines):

diff -r ba93e52a91e4 -r 50770bc063f5 sys/dev/nvmm/x86/nvmm_x86_svm.c
--- a/sys/dev/nvmm/x86/nvmm_x86_svm.c   Tue Feb 12 14:50:21 2019 +0000
+++ b/sys/dev/nvmm/x86/nvmm_x86_svm.c   Tue Feb 12 14:54:59 2019 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: nvmm_x86_svm.c,v 1.19 2019/02/04 12:11:18 maxv Exp $   */
+/*     $NetBSD: nvmm_x86_svm.c,v 1.20 2019/02/12 14:54:59 maxv Exp $   */
 
 /*
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nvmm_x86_svm.c,v 1.19 2019/02/04 12:11:18 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nvmm_x86_svm.c,v 1.20 2019/02/12 14:54:59 maxv Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -1194,12 +1194,6 @@
                tlb_need_flush = true;
        }
 
-       if (cpudata->tlb_want_flush || tlb_need_flush) {
-               vmcb->ctrl.tlb_ctrl = svm_ctrl_tlb_flush;
-       } else {
-               vmcb->ctrl.tlb_ctrl = 0;
-       }
-
        if (vcpu->hcpu_last != hcpu) {
                vmcb->ctrl.tsc_offset = cpudata->tsc_offset +
                    curcpu()->ci_data.cpu_cc_skew;
@@ -1210,6 +1204,12 @@
        svm_vcpu_guest_misc_enter(vcpu);
 
        while (1) {
+               if (cpudata->tlb_want_flush || tlb_need_flush) {
+                       vmcb->ctrl.tlb_ctrl = svm_ctrl_tlb_flush;
+               } else {
+                       vmcb->ctrl.tlb_ctrl = 0;
+               }
+
                s = splhigh();
                svm_vcpu_guest_fpu_enter(vcpu);
                svm_vmrun(cpudata->vmcb_pa, cpudata->gprs);
@@ -1219,9 +1219,8 @@
                svm_vmcb_cache_default(vmcb);
 
                if (vmcb->ctrl.exitcode != VMCB_EXITCODE_INVALID) {
-                       if (cpudata->tlb_want_flush) {
-                               cpudata->tlb_want_flush = false;
-                       }
+                       cpudata->tlb_want_flush = false;
+                       tlb_need_flush = false;
                        vcpu->hcpu_last = hcpu;
                }