[patch V4 12/37] x86/smpboot: Move synchronization masks to SMP boot code

Thomas Gleixner tglx at linutronix.de
Fri May 12 14:07:16 PDT 2023


From: Thomas Gleixner <tglx at linutronix.de>

The usage is in smpboot.c and not in the CPU initialization code.

The XEN_PV usage of cpu_callout_mask is obsolete as cpu_init() not longer
waits and cacheinfo has its own CPU mask now, so cpu_callout_mask can be
made static too.

Signed-off-by: Thomas Gleixner <tglx at linutronix.de>
Tested-by: Michael Kelley <mikelley at microsoft.com>
---
 arch/x86/include/asm/cpumask.h |    5 -----
 arch/x86/kernel/cpu/common.c   |   17 -----------------
 arch/x86/kernel/smpboot.c      |   16 ++++++++++++++++
 arch/x86/xen/smp_pv.c          |    3 ---
 4 files changed, 16 insertions(+), 25 deletions(-)
--- a/arch/x86/include/asm/cpumask.h
+++ b/arch/x86/include/asm/cpumask.h
@@ -4,11 +4,6 @@
 #ifndef __ASSEMBLY__
 #include <linux/cpumask.h>
 
-extern cpumask_var_t cpu_callin_mask;
-extern cpumask_var_t cpu_callout_mask;
-extern cpumask_var_t cpu_initialized_mask;
-extern cpumask_var_t cpu_sibling_setup_mask;
-
 extern void setup_cpu_local_masks(void);
 
 /*
--- a/arch/x86/kernel/cpu/common.c
+++ b/arch/x86/kernel/cpu/common.c
@@ -67,14 +67,6 @@
 
 u32 elf_hwcap2 __read_mostly;
 
-/* all of these masks are initialized in setup_cpu_local_masks() */
-cpumask_var_t cpu_initialized_mask;
-cpumask_var_t cpu_callout_mask;
-cpumask_var_t cpu_callin_mask;
-
-/* representing cpus for which sibling maps can be computed */
-cpumask_var_t cpu_sibling_setup_mask;
-
 /* Number of siblings per CPU package */
 int smp_num_siblings = 1;
 EXPORT_SYMBOL(smp_num_siblings);
@@ -169,15 +161,6 @@ static void ppin_init(struct cpuinfo_x86
 	clear_cpu_cap(c, info->feature);
 }
 
-/* correctly size the local cpu masks */
-void __init setup_cpu_local_masks(void)
-{
-	alloc_bootmem_cpumask_var(&cpu_initialized_mask);
-	alloc_bootmem_cpumask_var(&cpu_callin_mask);
-	alloc_bootmem_cpumask_var(&cpu_callout_mask);
-	alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
-}
-
 static void default_init(struct cpuinfo_x86 *c)
 {
 #ifdef CONFIG_X86_64
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -101,6 +101,13 @@ EXPORT_PER_CPU_SYMBOL(cpu_die_map);
 DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info);
 EXPORT_PER_CPU_SYMBOL(cpu_info);
 
+/* All of these masks are initialized in setup_cpu_local_masks() */
+static cpumask_var_t cpu_initialized_mask;
+static cpumask_var_t cpu_callout_mask;
+static cpumask_var_t cpu_callin_mask;
+/* Representing CPUs for which sibling maps can be computed */
+static cpumask_var_t cpu_sibling_setup_mask;
+
 /* Logical package management. We might want to allocate that dynamically */
 unsigned int __max_logical_packages __read_mostly;
 EXPORT_SYMBOL(__max_logical_packages);
@@ -1548,6 +1555,15 @@ early_param("possible_cpus", _setup_poss
 		set_cpu_possible(i, true);
 }
 
+/* correctly size the local cpu masks */
+void __init setup_cpu_local_masks(void)
+{
+	alloc_bootmem_cpumask_var(&cpu_initialized_mask);
+	alloc_bootmem_cpumask_var(&cpu_callin_mask);
+	alloc_bootmem_cpumask_var(&cpu_callout_mask);
+	alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
+}
+
 #ifdef CONFIG_HOTPLUG_CPU
 
 /* Recompute SMT state for all CPUs on offline */
--- a/arch/x86/xen/smp_pv.c
+++ b/arch/x86/xen/smp_pv.c
@@ -254,15 +254,12 @@ cpu_initialize_context(unsigned int cpu,
 	struct desc_struct *gdt;
 	unsigned long gdt_mfn;
 
-	/* used to tell cpu_init() that it can proceed with initialization */
-	cpumask_set_cpu(cpu, cpu_callout_mask);
 	if (cpumask_test_and_set_cpu(cpu, xen_cpu_initialized_map))
 		return 0;
 
 	ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
 	if (ctxt == NULL) {
 		cpumask_clear_cpu(cpu, xen_cpu_initialized_map);
-		cpumask_clear_cpu(cpu, cpu_callout_mask);
 		return -ENOMEM;
 	}
 




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