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Date:      Fri, 11 Feb 2022 06:52:07 GMT
From:      Colin Percival <cperciva@FreeBSD.org>
To:        src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org
Subject:   git: eb28df303b06 - stable/13 - Detect CPU type before asking VMWare for TSC freq
Message-ID:  <202202110652.21B6q7Ih031181@gitrepo.freebsd.org>

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The branch stable/13 has been updated by cperciva:

URL: https://cgit.FreeBSD.org/src/commit/?id=eb28df303b068c5db94943c9858e359975f7fa74

commit eb28df303b068c5db94943c9858e359975f7fa74
Author:     Colin Percival <cperciva@FreeBSD.org>
AuthorDate: 2022-01-04 07:00:39 +0000
Commit:     Colin Percival <cperciva@FreeBSD.org>
CommitDate: 2022-02-11 06:52:00 +0000

    Detect CPU type before asking VMWare for TSC freq
    
    This allows us to set tsc_is_invariant and select appropriately
    fenced versions of RDTSC based on the CPU type.
    
    Reviewed by:    markj
    Sponsored by:   https://www.patreon.com/cperciva
    
    (cherry picked from commit fd980feb574d0924918b42cd449cedf557dfb9e0)
---
 sys/x86/x86/tsc.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/sys/x86/x86/tsc.c b/sys/x86/x86/tsc.c
index 1e63c313c7e4..1b6c8282e44e 100644
--- a/sys/x86/x86/tsc.c
+++ b/sys/x86/x86/tsc.c
@@ -134,7 +134,6 @@ tsc_freq_vmware(void)
 		if (regs[1] != UINT_MAX)
 			tsc_freq = regs[0] | ((uint64_t)regs[1] << 32);
 	}
-	tsc_is_invariant = 1;
 	tsc_early_calib_exact = 1;
 }
 
@@ -268,11 +267,6 @@ probe_tsc_freq(void)
 			tsc_perf_stat = 1;
 	}
 
-	if (vm_guest == VM_GUEST_VMWARE) {
-		tsc_freq_vmware();
-		return;
-	}
-
 	switch (cpu_vendor_id) {
 	case CPU_VENDOR_AMD:
 	case CPU_VENDOR_HYGON:
@@ -311,6 +305,11 @@ probe_tsc_freq(void)
 		break;
 	}
 
+	if (vm_guest == VM_GUEST_VMWARE) {
+		tsc_freq_vmware();
+		return;
+	}
+
 	if (tsc_freq_cpuid(&tsc_freq)) {
 		/*
 		 * If possible, use the value obtained from CPUID as the initial



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