Module Name: src
Committed By: maxv
Date: Wed Feb 13 07:04:13 UTC 2019
Modified Files:
src/sys/dev/nvmm/x86: nvmm_x86_svm.c
Log Message:
Micro optimization: the STAR/LSTAR/CSTAR/SFMASK MSRs are static, so rather
than saving them on each VMENTRY, save them only once, at VCPU creation
time.
To generate a diff of this commit:
cvs rdiff -u -r1.20 -r1.21 src/sys/dev/nvmm/x86/nvmm_x86_svm.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/nvmm/x86/nvmm_x86_svm.c
diff -u src/sys/dev/nvmm/x86/nvmm_x86_svm.c:1.20 src/sys/dev/nvmm/x86/nvmm_x86_svm.c:1.21
--- src/sys/dev/nvmm/x86/nvmm_x86_svm.c:1.20 Tue Feb 12 14:54:59 2019
+++ src/sys/dev/nvmm/x86/nvmm_x86_svm.c Wed Feb 13 07:04:12 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: nvmm_x86_svm.c,v 1.20 2019/02/12 14:54:59 maxv Exp $ */
+/* $NetBSD: nvmm_x86_svm.c,v 1.21 2019/02/13 07:04:12 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 1.20 2019/02/12 14:54:59 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nvmm_x86_svm.c,v 1.21 2019/02/13 07:04:12 maxv Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -1157,10 +1157,6 @@ svm_vcpu_guest_misc_enter(struct nvmm_cp
{
struct svm_cpudata *cpudata = vcpu->cpudata;
- cpudata->star = rdmsr(MSR_STAR);
- cpudata->lstar = rdmsr(MSR_LSTAR);
- cpudata->cstar = rdmsr(MSR_CSTAR);
- cpudata->sfmask = rdmsr(MSR_SFMASK);
cpudata->fsbase = rdmsr(MSR_FSBASE);
cpudata->kernelgsbase = rdmsr(MSR_KERNELGSBASE);
}
@@ -1592,6 +1588,12 @@ svm_vcpu_init(struct nvmm_machine *mach,
/* Bluntly hide the host TSC. */
cpudata->tsc_offset = rdtsc();
+
+ /* These MSRs are static. */
+ cpudata->star = rdmsr(MSR_STAR);
+ cpudata->lstar = rdmsr(MSR_LSTAR);
+ cpudata->cstar = rdmsr(MSR_CSTAR);
+ cpudata->sfmask = rdmsr(MSR_SFMASK);
}
static int
