From: Thomas Gleixner <tglx@linutronix.de>
Date: Thu, 30 Mar 2023 07:52:16 +0000 (+0200)
Subject: x86/topology: Store extended topology leaf information
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=0b8fbd5b976b43a87c50983a343fc02f738b5f8c;p=users%2Fdwmw2%2Flinux.git

x86/topology: Store extended topology leaf information

Save the extended topology leaf number if it exists and is valid in
preparation of parallel CPU bringup.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---

diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h
index 2ba57588e937f..0226565ec6320 100644
--- a/arch/x86/include/asm/topology.h
+++ b/arch/x86/include/asm/topology.h
@@ -121,6 +121,7 @@ extern unsigned int __max_die_per_package;
 #define topology_core_cpumask(cpu)		(per_cpu(cpu_core_map, cpu))
 #define topology_sibling_cpumask(cpu)		(per_cpu(cpu_sibling_map, cpu))
 
+extern unsigned int topology_extended_leaf;
 extern unsigned int __max_logical_packages;
 #define topology_max_packages()			(__max_logical_packages)
 
diff --git a/arch/x86/kernel/cpu/topology.c b/arch/x86/kernel/cpu/topology.c
index 5e868b62a7c4e..bd72368cdce06 100644
--- a/arch/x86/kernel/cpu/topology.c
+++ b/arch/x86/kernel/cpu/topology.c
@@ -29,6 +29,8 @@ unsigned int __max_die_per_package __read_mostly = 1;
 EXPORT_SYMBOL(__max_die_per_package);
 
 #ifdef CONFIG_SMP
+unsigned int topology_extended_leaf __ro_after_init;
+
 /*
  * Check if given CPUID extended topology "leaf" is implemented
  */
@@ -72,6 +74,7 @@ int detect_extended_topology_early(struct cpuinfo_x86 *c)
 	if (leaf < 0)
 		return -1;
 
+	topology_extended_leaf = leaf;
 	set_cpu_cap(c, X86_FEATURE_XTOPOLOGY);
 
 	cpuid_count(leaf, SMT_LEVEL, &eax, &ebx, &ecx, &edx);