From: Sean Christopherson <seanjc@google.com>
To: Sean Christopherson <seanjc@google.com>,
Paolo Bonzini <pbonzini@redhat.com>
Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Maxim Levitsky <mlevitsk@redhat.com>
Subject: Re: [PATCH] KVM: selftests: Use data load to trigger LLC references/misses in Intel PMU
Date: Thu, 9 Jan 2025 11:47:17 -0800 [thread overview]
Message-ID: <173645118101.885497.8247079551108053264.b4-ty@google.com> (raw)
In-Reply-To: <20241127235627.4049619-1-seanjc@google.com>
On Wed, 27 Nov 2024 15:56:27 -0800, Sean Christopherson wrote:
> In the PMU counters test, add a data load in the measured loop and target
> the data with CLFLUSH{OPT} in order to (try to) guarantee the loop
> generates LLC misses and fills. Per the SDM, some hardware prefetchers
> are allowed to omit relevant PMU events, and Emerald Rapids (and possibly
> Sapphire Rapids) appears to have gained an instruction prefetcher that
> bypasses event counts. E.g. the test will consistently fail on EMR CPUs,
> but then pass with seemingly benign changes to the code.
>
> [...]
Applied to kvm-x86 selftests, thanks!
[1/1] KVM: selftests: Use data load to trigger LLC references/misses in Intel PMU
https://github.com/kvm-x86/linux/commit/7803339fa929
--
https://github.com/kvm-x86/linux/tree/next
prev parent reply other threads:[~2025-01-09 19:48 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2024-11-27 23:56 Sean Christopherson
2025-01-09 19:47 ` Sean Christopherson [this message]
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=173645118101.885497.8247079551108053264.b4-ty@google.com \
--to=seanjc@google.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mlevitsk@redhat.com \
--cc=pbonzini@redhat.com \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®