From: Dave Hansen <dave.hansen@intel.com>
To: Paolo Bonzini <pbonzini@redhat.com>, Jon Kohler <jon@nutanix.com>
Cc: Babu Moger <babu.moger@amd.com>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
Sean Christopherson <seanjc@google.com>,
Vitaly Kuznetsov <vkuznets@redhat.com>,
Wanpeng Li <wanpengli@tencent.com>,
Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
Fenghua Yu <fenghua.yu@intel.com>,
Yu-cheng Yu <yu-cheng.yu@intel.com>,
Tony Luck <tony.luck@intel.com>, Uros Bizjak <ubizjak@gmail.com>,
Petteri Aimonen <jpa@git.mail.kapsi.fi>,
Kan Liang <kan.liang@linux.intel.com>,
Andrew Morton <akpm@linux-foundation.org>,
Mike Rapoport <rppt@kernel.org>,
Benjamin Thiel <b.thiel@posteo.de>,
Fan Yang <Fan_Yang@sjtu.edu.cn>, Juergen Gross <jgross@suse.com>,
Dave Jiang <dave.jiang@intel.com>,
"Peter Zijlstra (Intel)" <peterz@infradead.org>,
Ricardo Neri <ricardo.neri-calderon@linux.intel.com>,
Arvind Sankar <nivedita@alum.mit.edu>,
linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Subject: Re: [PATCH] KVM: x86: add hint to skip hidden rdpkru under kvm_load_host_xsave_state
Date: Fri, 7 May 2021 09:58:38 -0700 [thread overview]
Message-ID: <709442d7-68e8-32a8-05b4-8a16748d9f11@intel.com> (raw)
In-Reply-To: <16af038e-5b30-2509-4e3b-3b3ed9d4b81e@redhat.com>
On 5/7/21 9:52 AM, Paolo Bonzini wrote:
> This can be optimized as well, can't it? This means that the only case
> that needs the rdpkru is in switch_fpu_finish, and __write_pkru can be
> removed completely:
>
> - do the rdpkru+wrpkru in switch_fpu_finish
>
> - just use wrpkru in KVM
I was going to suggest exactly the same thing. It doesn't require the
compiler to be smart, and wrpkru() is available in the same header as
__write_pkru().
I also detest the mysterious true/false arguments to functions where you
have no clue what they're doing at the call site without comments.
next prev parent reply other threads:[~2021-05-07 16:58 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-05-07 16:44 [PATCH] KVM: x86: add hint to skip hidden rdpkru under kvm_load_host_xsave_state Jon Kohler
2021-05-07 16:52 ` Paolo Bonzini
2021-05-07 16:58 ` Dave Hansen [this message]
2021-05-07 17:13 ` Jon Kohler
2021-05-14 5:11 ` Andy Lutomirski
2021-05-17 2:50 ` Jon Kohler
2021-05-17 16:35 ` Tom Lendacky
2021-05-17 7:46 ` Paolo Bonzini
2021-05-17 17:39 ` Sean Christopherson
2021-05-17 17:55 ` Dave Hansen
2021-05-17 18:02 ` Sean Christopherson
[not found] ` <4e6f7056-6b66-46b9-9eac-922ae1c7b526@www.fastmail.com>
2021-05-17 17:59 ` Dave Hansen
2021-05-17 18:04 ` Sean Christopherson
2021-05-17 18:15 ` Jim Mattson
2021-05-17 18:34 ` Sean Christopherson
2021-05-19 22:44 ` Dave Hansen
2021-05-19 23:15 ` Andy Lutomirski
2021-05-17 13:54 ` Dave Hansen
2021-05-17 16:43 ` Paolo Bonzini
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=709442d7-68e8-32a8-05b4-8a16748d9f11@intel.com \
--to=dave.hansen@intel.com \
--cc=Fan_Yang@sjtu.edu.cn \
--cc=akpm@linux-foundation.org \
--cc=b.thiel@posteo.de \
--cc=babu.moger@amd.com \
--cc=bp@alien8.de \
--cc=dave.jiang@intel.com \
--cc=fenghua.yu@intel.com \
--cc=hpa@zytor.com \
--cc=jgross@suse.com \
--cc=jmattson@google.com \
--cc=jon@nutanix.com \
--cc=joro@8bytes.org \
--cc=jpa@git.mail.kapsi.fi \
--cc=kan.liang@linux.intel.com \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=nivedita@alum.mit.edu \
--cc=pbonzini@redhat.com \
--cc=peterz@infradead.org \
--cc=ricardo.neri-calderon@linux.intel.com \
--cc=rppt@kernel.org \
--cc=seanjc@google.com \
--cc=tglx@linutronix.de \
--cc=tony.luck@intel.com \
--cc=ubizjak@gmail.com \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--cc=x86@kernel.org \
--cc=yu-cheng.yu@intel.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;
as well as URLs for NNTP newsgroup(s).