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[PATCH v1 2/2] x86/cacheinfo: Standardize header files and CPUID references

Ahmed S. Darwish posted 2 patches 8 months, 1 week ago
[PATCH v1 2/2] x86/cacheinfo: Standardize header files and CPUID references
Posted by Ahmed S. Darwish 8 months, 1 week ago 
Reference header files using their canonical form <linux/cacheinfo.h>.

Standardize on CPUID(0xN), instead of CPUID(N), for all standard leaves.
This removes ambiguity and aligns them with their extended counterparts
like CPUID(0x8000001d).

References: 0dd09e215a39 ("x86/cacheinfo: Apply maintainer-tip coding style fixes")
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
---
 arch/x86/kernel/cpu/cacheinfo.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c
index 52727f8c0006..cc7ae2bdcf4a 100644
--- a/arch/x86/kernel/cpu/cacheinfo.c
+++ b/arch/x86/kernel/cpu/cacheinfo.c
@@ -3,9 +3,9 @@
  * x86 CPU caches detection and configuration
  *
  * Previous changes
- * - Venkatesh Pallipadi:		Cache identification through CPUID(4)
+ * - Venkatesh Pallipadi:		Cache identification through CPUID(0x4)
  * - Ashok Raj <ashok.raj@intel.com>:	Work with CPU hotplug infrastructure
- * - Andi Kleen / Andreas Herrmann:	CPUID(4) emulation on AMD
+ * - Andi Kleen / Andreas Herrmann:	CPUID(0x4) emulation on AMD
  */
 
 #include <linux/cacheinfo.h>
@@ -78,7 +78,7 @@ struct _cpuid4_info {
 	unsigned long size;
 };
 
-/* Map CPUID(4) EAX.cache_type to linux/cacheinfo.h types */
+/* Map CPUID(0x4) EAX.cache_type to <linux/cacheinfo.h> types */
 static const enum cache_type cache_type_map[] = {
 	[CTYPE_NULL]	= CACHE_TYPE_NOCACHE,
 	[CTYPE_DATA]	= CACHE_TYPE_DATA,
@@ -87,7 +87,7 @@ static const enum cache_type cache_type_map[] = {
 };
 
 /*
- * Fallback AMD CPUID(4) emulation
+ * Fallback AMD CPUID(0x4) emulation
  * AMD CPUs with TOPOEXT can just use CPUID(0x8000001d)
  *
  * @AMD_L2_L3_INVALID_ASSOC: cache info for the respective L2/L3 cache should
@@ -361,7 +361,7 @@ static void intel_cacheinfo_done(struct cpuinfo_x86 *c, unsigned int l3,
 {
 	/*
 	 * If llc_id is still unset, then cpuid_level < 4, which implies
-	 * that the only possibility left is SMT.  Since CPUID(2) doesn't
+	 * that the only possibility left is SMT.  Since CPUID(0x2) doesn't
 	 * specify any shared caches and SMT shares all caches, we can
 	 * unconditionally set LLC ID to the package ID so that all
 	 * threads share it.
@@ -376,7 +376,7 @@ static void intel_cacheinfo_done(struct cpuinfo_x86 *c, unsigned int l3,
 }
 
 /*
- * Legacy Intel CPUID(2) path if CPUID(4) is not available.
+ * Legacy Intel CPUID(0x2) path if CPUID(0x4) is not available.
  */
 static void intel_cacheinfo_0x2(struct cpuinfo_x86 *c)
 {
@@ -466,7 +466,7 @@ static bool intel_cacheinfo_0x4(struct cpuinfo_x86 *c)
 
 void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 {
-	/* Don't use CPUID(2) if CPUID(4) is supported. */
+	/* Don't use CPUID(0x2) if CPUID(0x4) is supported. */
 	if (intel_cacheinfo_0x4(c))
 		return;
 
@@ -474,7 +474,7 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 }
 
 /*
- * linux/cacheinfo.h shared_cpu_map setup, AMD/Hygon
+ * <linux/cacheinfo.h> shared_cpu_map setup, AMD/Hygon
  */
 static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
 				    const struct _cpuid4_info *id4)
@@ -533,7 +533,7 @@ static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
 }
 
 /*
- * linux/cacheinfo.h shared_cpu_map setup, Intel + fallback AMD/Hygon
+ * <linux/cacheinfo.h> shared_cpu_map setup, Intel + fallback AMD/Hygon
  */
 static void __cache_cpumap_setup(unsigned int cpu, int index,
 				 const struct _cpuid4_info *id4)
@@ -599,7 +599,7 @@ int init_cache_level(unsigned int cpu)
 }
 
 /*
- * The max shared threads number comes from CPUID(4) EAX[25-14] with input
+ * The max shared threads number comes from CPUID(0x4) EAX[25-14] with input
  * ECX as cache index. Then right shift apicid by the number's order to get
  * cache id for this cache node.
  */
-- 
2.49.0
[tip: x86/cpu] x86/cacheinfo: Standardize header files and CPUID references
Posted by tip-bot2 for Ahmed S. Darwish 8 months, 1 week ago 
The following commit has been merged into the x86/cpu branch of tip:

Commit-ID:     62e565273993ee47c82ca2975e65ce4bec3c3697
Gitweb:        https://git.kernel.org/tip/62e565273993ee47c82ca2975e65ce4bec3c3697
Author:        Ahmed S. Darwish <darwi@linutronix.de>
AuthorDate:    Fri, 11 Apr 2025 09:04:01 +02:00
Committer:     Ingo Molnar <mingo@kernel.org>
CommitterDate: Fri, 11 Apr 2025 11:14:55 +02:00

x86/cacheinfo: Standardize header files and CPUID references

Reference header files using their canonical form <linux/cacheinfo.h>.

Standardize on CPUID(0xN), instead of CPUID(N), for all standard leaves.
This removes ambiguity and aligns them with their extended counterparts
like CPUID(0x8000001d).

References: 0dd09e215a39 ("x86/cacheinfo: Apply maintainer-tip coding style fixes")
Signed-off-by: Ahmed S. Darwish <darwi@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: John Ogness <john.ogness@linutronix.de>
Link: https://lore.kernel.org/r/20250411070401.1358760-3-darwi@linutronix.de
---
 arch/x86/kernel/cpu/cacheinfo.c | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kernel/cpu/cacheinfo.c b/arch/x86/kernel/cpu/cacheinfo.c
index 52727f8..cc7ae2b 100644
--- a/arch/x86/kernel/cpu/cacheinfo.c
+++ b/arch/x86/kernel/cpu/cacheinfo.c
@@ -3,9 +3,9 @@
  * x86 CPU caches detection and configuration
  *
  * Previous changes
- * - Venkatesh Pallipadi:		Cache identification through CPUID(4)
+ * - Venkatesh Pallipadi:		Cache identification through CPUID(0x4)
  * - Ashok Raj <ashok.raj@intel.com>:	Work with CPU hotplug infrastructure
- * - Andi Kleen / Andreas Herrmann:	CPUID(4) emulation on AMD
+ * - Andi Kleen / Andreas Herrmann:	CPUID(0x4) emulation on AMD
  */
 
 #include <linux/cacheinfo.h>
@@ -78,7 +78,7 @@ struct _cpuid4_info {
 	unsigned long size;
 };
 
-/* Map CPUID(4) EAX.cache_type to linux/cacheinfo.h types */
+/* Map CPUID(0x4) EAX.cache_type to <linux/cacheinfo.h> types */
 static const enum cache_type cache_type_map[] = {
 	[CTYPE_NULL]	= CACHE_TYPE_NOCACHE,
 	[CTYPE_DATA]	= CACHE_TYPE_DATA,
@@ -87,7 +87,7 @@ static const enum cache_type cache_type_map[] = {
 };
 
 /*
- * Fallback AMD CPUID(4) emulation
+ * Fallback AMD CPUID(0x4) emulation
  * AMD CPUs with TOPOEXT can just use CPUID(0x8000001d)
  *
  * @AMD_L2_L3_INVALID_ASSOC: cache info for the respective L2/L3 cache should
@@ -361,7 +361,7 @@ static void intel_cacheinfo_done(struct cpuinfo_x86 *c, unsigned int l3,
 {
 	/*
 	 * If llc_id is still unset, then cpuid_level < 4, which implies
-	 * that the only possibility left is SMT.  Since CPUID(2) doesn't
+	 * that the only possibility left is SMT.  Since CPUID(0x2) doesn't
 	 * specify any shared caches and SMT shares all caches, we can
 	 * unconditionally set LLC ID to the package ID so that all
 	 * threads share it.
@@ -376,7 +376,7 @@ static void intel_cacheinfo_done(struct cpuinfo_x86 *c, unsigned int l3,
 }
 
 /*
- * Legacy Intel CPUID(2) path if CPUID(4) is not available.
+ * Legacy Intel CPUID(0x2) path if CPUID(0x4) is not available.
  */
 static void intel_cacheinfo_0x2(struct cpuinfo_x86 *c)
 {
@@ -466,7 +466,7 @@ static bool intel_cacheinfo_0x4(struct cpuinfo_x86 *c)
 
 void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 {
-	/* Don't use CPUID(2) if CPUID(4) is supported. */
+	/* Don't use CPUID(0x2) if CPUID(0x4) is supported. */
 	if (intel_cacheinfo_0x4(c))
 		return;
 
@@ -474,7 +474,7 @@ void init_intel_cacheinfo(struct cpuinfo_x86 *c)
 }
 
 /*
- * linux/cacheinfo.h shared_cpu_map setup, AMD/Hygon
+ * <linux/cacheinfo.h> shared_cpu_map setup, AMD/Hygon
  */
 static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
 				    const struct _cpuid4_info *id4)
@@ -533,7 +533,7 @@ static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
 }
 
 /*
- * linux/cacheinfo.h shared_cpu_map setup, Intel + fallback AMD/Hygon
+ * <linux/cacheinfo.h> shared_cpu_map setup, Intel + fallback AMD/Hygon
  */
 static void __cache_cpumap_setup(unsigned int cpu, int index,
 				 const struct _cpuid4_info *id4)
@@ -599,7 +599,7 @@ int init_cache_level(unsigned int cpu)
 }
 
 /*
- * The max shared threads number comes from CPUID(4) EAX[25-14] with input
+ * The max shared threads number comes from CPUID(0x4) EAX[25-14] with input
  * ECX as cache index. Then right shift apicid by the number's order to get
  * cache id for this cache node.
  */

Patchew 2.1-devel-b67e4c2

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