From 11e907339d6d25bfbd022810c567071efa25089b Mon Sep 17 00:00:00 2001 From: markj Date: Thu, 4 Apr 2019 02:08:36 +0000 Subject: [PATCH] MFC r345359, r345384: Don't attempt to measure TSC skew when running as a VM guest. PR: 218452 git-svn-id: svn://svn.freebsd.org/base/stable/10@345869 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- sys/cddl/dev/dtrace/amd64/dtrace_subr.c | 3 +++ sys/cddl/dev/dtrace/i386/dtrace_subr.c | 3 +++ 2 files changed, 6 insertions(+) diff --git a/sys/cddl/dev/dtrace/amd64/dtrace_subr.c b/sys/cddl/dev/dtrace/amd64/dtrace_subr.c index 1520924be..29d150976 100644 --- a/sys/cddl/dev/dtrace/amd64/dtrace_subr.c +++ b/sys/cddl/dev/dtrace/amd64/dtrace_subr.c @@ -405,6 +405,9 @@ dtrace_gethrtime_init(void *arg) */ nsec_scale = ((uint64_t)NANOSEC << SCALE_SHIFT) / tsc_f; + if (vm_guest != VM_GUEST_NO) + return; + /* The current CPU is the reference one. */ sched_pin(); tsc_skew[curcpu] = 0; diff --git a/sys/cddl/dev/dtrace/i386/dtrace_subr.c b/sys/cddl/dev/dtrace/i386/dtrace_subr.c index 140b8bc7f..5a419cf59 100644 --- a/sys/cddl/dev/dtrace/i386/dtrace_subr.c +++ b/sys/cddl/dev/dtrace/i386/dtrace_subr.c @@ -414,6 +414,9 @@ dtrace_gethrtime_init(void *arg) */ nsec_scale = ((uint64_t)NANOSEC << SCALE_SHIFT) / tsc_f; + if (vm_guest != VM_GUEST_NO) + return; + /* The current CPU is the reference one. */ sched_pin(); tsc_skew[curcpu] = 0; -- 2.45.0