All of lore.kernel.org
 help / color / mirror / Atom feed
From: zhenwei pi <pizhenwei@bytedance.com>
To: tglx@linutronix.de, pbonzini@redhat.com
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
	x86@kernel.org, zhenwei pi <pizhenwei@bytedance.com>
Subject: [PATCH v2 2/2] KVM: x86: Use x86_get_cpufreq_khz to get frequency for kvmclock
Date: Wed,  1 Dec 2021 11:00:09 +0800	[thread overview]
Message-ID: <20211201030009.89740-1-pizhenwei@bytedance.com> (raw)

# Ignore previous [PATCH v2 2/2] KVM: x86: use x86_get_freq to get freq for kvmclock, and remove this line

If the host side supports APERF&MPERF feature, the guest side may get
mismatched frequency.

KVM uses x86_get_cpufreq_khz() to get the same frequency for guest side.

Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
---
 arch/x86/kvm/x86.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5a403d92833f..125ed3c8b21a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8305,10 +8305,8 @@ static void tsc_khz_changed(void *data)
 
 	if (data)
 		khz = freq->new;
-	else if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
-		khz = cpufreq_quick_get(raw_smp_processor_id());
 	if (!khz)
-		khz = tsc_khz;
+		khz = x86_get_cpufreq_khz(raw_smp_processor_id());
 	__this_cpu_write(cpu_tsc_khz, khz);
 }
 
-- 
2.25.1


                 reply	other threads:[~2021-12-01  3:02 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211201030009.89740-1-pizhenwei@bytedance.com \
    --to=pizhenwei@bytedance.com \
    --cc=kvm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=pbonzini@redhat.com \
    --cc=tglx@linutronix.de \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.