From: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
To: x86@kernel.org
Cc: linux-kernel@vger.kernel.org, Dave Jones <davej@codemonkey.org.uk>
Subject: [PATCH RFC] x86: fix confusing name of /proc/cpuinfo "ht" flag
Date: Wed, 11 Nov 2009 21:34:34 +0100 [thread overview]
Message-ID: <200911112134.34261.bzolnier@gmail.com> (raw)
"ht" flag indicates only ability to detect siblings not HT presence itself.
Inspired by:
http://www.codemonkey.org.uk/2009/11/10/common-hyperthreading-misconception/
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
---
It could be that there are some user-space programs depending on "ht"
flag so the patch is marked as RFC..
arch/x86/include/asm/cpufeature.h | 4 ++--
arch/x86/kernel/cpu/capflags.c | 2 +-
arch/x86/kernel/cpu/common.c | 2 +-
3 files changed, 4 insertions(+), 4 deletions(-)
Index: b/arch/x86/include/asm/cpufeature.h
===================================================================
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -42,7 +42,7 @@
#define X86_FEATURE_XMM (0*32+25) /* "sse" */
#define X86_FEATURE_XMM2 (0*32+26) /* "sse2" */
#define X86_FEATURE_SELFSNOOP (0*32+27) /* "ss" CPU self snoop */
-#define X86_FEATURE_HT (0*32+28) /* Hyper-Threading */
+#define X86_FEATURE_HT_DETECTION (0*32+28) /* Hyper-Threading detection */
#define X86_FEATURE_ACC (0*32+29) /* "tm" Automatic clock control */
#define X86_FEATURE_IA64 (0*32+30) /* IA-64 processor */
#define X86_FEATURE_PBE (0*32+31) /* Pending Break Enable */
@@ -220,7 +220,7 @@ extern const char * const x86_power_flag
#define cpu_has_xmm2 boot_cpu_has(X86_FEATURE_XMM2)
#define cpu_has_xmm3 boot_cpu_has(X86_FEATURE_XMM3)
#define cpu_has_aes boot_cpu_has(X86_FEATURE_AES)
-#define cpu_has_ht boot_cpu_has(X86_FEATURE_HT)
+#define cpu_has_ht_detection boot_cpu_has(X86_FEATURE_HT_DETECTION)
#define cpu_has_mp boot_cpu_has(X86_FEATURE_MP)
#define cpu_has_nx boot_cpu_has(X86_FEATURE_NX)
#define cpu_has_k6_mtrr boot_cpu_has(X86_FEATURE_K6_MTRR)
Index: b/arch/x86/kernel/cpu/capflags.c
===================================================================
--- a/arch/x86/kernel/cpu/capflags.c
+++ b/arch/x86/kernel/cpu/capflags.c
@@ -27,7 +27,7 @@ const char * const x86_cap_flags[NCAPINT
[X86_FEATURE_XMM] = "sse",
[X86_FEATURE_XMM2] = "sse2",
[X86_FEATURE_SELFSNOOP] = "ss",
- [X86_FEATURE_HT] = "ht",
+ [X86_FEATURE_HT_DETECTION] = "ht_detection",
[X86_FEATURE_ACC] = "tm",
[X86_FEATURE_IA64] = "ia64",
[X86_FEATURE_PBE] = "pbe",
Index: b/arch/x86/kernel/cpu/common.c
===================================================================
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -433,7 +433,7 @@ void __cpuinit detect_ht(struct cpuinfo_
u32 eax, ebx, ecx, edx;
int index_msb, core_bits;
- if (!cpu_has(c, X86_FEATURE_HT))
+ if (!cpu_has(c, X86_FEATURE_HT_DETECTION))
return;
if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
next reply other threads:[~2009-11-11 20:35 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-11 20:34 Bartlomiej Zolnierkiewicz [this message]
2009-11-11 20:46 ` [PATCH RFC] x86: fix confusing name of /proc/cpuinfo "ht" flag Chris Friesen
2009-11-12 17:07 ` Alexander Clouter
2009-11-11 21:35 ` Jeff Garzik
2009-11-12 6:59 ` Ingo Molnar
2009-11-12 7:08 ` H. Peter Anvin
2009-11-12 8:13 ` Ingo Molnar
2009-11-12 15:18 ` H. Peter Anvin
2009-11-12 17:59 ` Ingo Molnar
2009-11-12 18:37 ` Dave Jones
2009-11-12 19:49 ` H. Peter Anvin
2009-11-13 7:42 ` Ingo Molnar
2009-11-13 10:24 ` Bartlomiej Zolnierkiewicz
2009-11-13 7:17 ` H. Peter Anvin
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