From: Kyung Min Park <kyung.min.park@intel.com>
To: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de,
hpa@zytor.com, pbonzini@redhat.com,
sean.j.christopherson@intel.com, jmattson@google.com,
joro@8bytes.org, vkuznets@redhat.com, wanpengli@tencent.com,
kyung.min.park@intel.com, cathy.zhang@intel.com
Subject: [PATCH 2/2] x86: Expose AVX512_FP16 for supported CPUID
Date: Mon, 7 Dec 2020 19:34:41 -0800 [thread overview]
Message-ID: <20201208033441.28207-3-kyung.min.park@intel.com> (raw)
In-Reply-To: <20201208033441.28207-1-kyung.min.park@intel.com>
From: Cathy Zhang <cathy.zhang@intel.com>
AVX512_FP16 is supported by Intel processors, like Sapphire Rapids.
It could gain better performance for it's faster compared to FP32
while meets the precision or magnitude requirement. It's availability
is indicated by CPUID.(EAX=7,ECX=0):EDX[bit 23].
Expose it in KVM supported CPUID, then guest could make use of it.
Signed-off-by: Cathy Zhang <cathy.zhang@intel.com>
Signed-off-by: Kyung Min Park <kyung.min.park@intel.com>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
---
arch/x86/kvm/cpuid.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index e83bfe2daf82..d7707cfc9401 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -416,7 +416,7 @@ void kvm_set_cpu_caps(void)
F(AVX512_4VNNIW) | F(AVX512_4FMAPS) | F(SPEC_CTRL) |
F(SPEC_CTRL_SSBD) | F(ARCH_CAPABILITIES) | F(INTEL_STIBP) |
F(MD_CLEAR) | F(AVX512_VP2INTERSECT) | F(FSRM) |
- F(SERIALIZE) | F(TSXLDTRK)
+ F(SERIALIZE) | F(TSXLDTRK) | F(AVX512_FP16)
);
/* TSC_ADJUST and ARCH_CAPABILITIES are emulated in software. */
--
2.17.1
next prev parent reply other threads:[~2020-12-08 3:57 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-12-08 3:34 [PATCH 0/2] Enumerate and expose AVX512_FP16 feature Kyung Min Park
2020-12-08 3:34 ` [PATCH 1/2] Enumerate AVX512 FP16 CPUID feature flag Kyung Min Park
2020-12-08 9:28 ` Borislav Petkov
2020-12-08 3:34 ` Kyung Min Park [this message]
2020-12-11 1:03 ` [PATCH 2/2] x86: Expose AVX512_FP16 for supported CPUID Sean Christopherson
2020-12-11 23:42 ` [PATCH 0/2] Enumerate and expose AVX512_FP16 feature Paolo Bonzini
2020-12-15 1:43 ` Zhang, Cathy
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=20201208033441.28207-3-kyung.min.park@intel.com \
--to=kyung.min.park@intel.com \
--cc=bp@alien8.de \
--cc=cathy.zhang@intel.com \
--cc=hpa@zytor.com \
--cc=jmattson@google.com \
--cc=joro@8bytes.org \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@redhat.com \
--cc=pbonzini@redhat.com \
--cc=sean.j.christopherson@intel.com \
--cc=tglx@linutronix.de \
--cc=vkuznets@redhat.com \
--cc=wanpengli@tencent.com \
--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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox