31 lines
1.2 KiB
Diff
31 lines
1.2 KiB
Diff
|
commit f3a99b2216114f89b20329ae7664b764248b4bbd
|
||
|
|
Author: H.J. Lu <hjl.tools@gmail.com>
|
||
|
|
Date: Mon Dec 6 07:14:12 2021 -0800
|
||
|
|
|
||
|
|
x86: Don't set Prefer_No_AVX512 for processors with AVX512 and AVX-VNNI
|
||
|
|
|
||
|
|
Don't set Prefer_No_AVX512 on processors with AVX512 and AVX-VNNI since
|
||
|
|
they won't lower CPU frequency when ZMM load and store instructions are
|
||
|
|
used.
|
||
|
|
|
||
|
|
(cherry picked from commit ceeffe968c01b1202e482f4855cb6baf5c6cb713)
|
||
|
|
|
||
|
|
diff --git a/sysdeps/x86/cpu-features.c b/sysdeps/x86/cpu-features.c
|
||
|
|
index f4d4049e391cbabd..09590d8794b1c6fb 100644
|
||
|
|
--- a/sysdeps/x86/cpu-features.c
|
||
|
|
+++ b/sysdeps/x86/cpu-features.c
|
||
|
|
@@ -566,8 +566,11 @@ disable_tsx:
|
||
|
|
|= bit_arch_Prefer_No_VZEROUPPER;
|
||
|
|
else
|
||
|
|
{
|
||
|
|
- cpu_features->preferred[index_arch_Prefer_No_AVX512]
|
||
|
|
- |= bit_arch_Prefer_No_AVX512;
|
||
|
|
+ /* Processors with AVX512 and AVX-VNNI won't lower CPU frequency
|
||
|
|
+ when ZMM load and store instructions are used. */
|
||
|
|
+ if (!CPU_FEATURES_CPU_P (cpu_features, AVX_VNNI))
|
||
|
|
+ cpu_features->preferred[index_arch_Prefer_No_AVX512]
|
||
|
|
+ |= bit_arch_Prefer_No_AVX512;
|
||
|
|
|
||
|
|
/* Avoid RTM abort triggered by VZEROUPPER inside a
|
||
|
|
transactionally executing RTM region. */
|