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A set of updates for CPU hotplug:

Browse source 
- Prepare the core for supporting parallel hotplug on loongarch
 
   - A small set of cleanups and enhancements
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Merge tag 'smp-core-2024-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull CPU hotplug updates from Thomas Gleixner:

 - Prepare the core for supporting parallel hotplug on loongarch

 - A small set of cleanups and enhancements

* tag 'smp-core-2024-09-16' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smp: Mark smp_prepare_boot_cpu() __init
  cpu: Fix W=1 build kernel-doc warning
  cpu/hotplug: Provide weak fallback for arch_cpuhp_init_parallel_bringup()
  cpu/hotplug: Make HOTPLUG_PARALLEL independent of HOTPLUG_SMT
This commit is contained in:
Linus Torvalds 2024-09-17 06:56:31 +02:00
commit 97e17c08a4
4 changed files with 20 additions and 6 deletions
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2
arch/mips/kernel/smp.c
View file

@ -439,7 +439,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
}
/* preload SMP state for boot cpu */
void smp_prepare_boot_cpu(void)
void __init smp_prepare_boot_cpu(void)
{
if (mp_ops->prepare_boot_cpu)
mp_ops->prepare_boot_cpu();

2
arch/powerpc/kernel/smp.c
View file

@ -1166,7 +1166,7 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
cpu_smt_set_num_threads(num_threads, threads_per_core);
}
void smp_prepare_boot_cpu(void)
void __init smp_prepare_boot_cpu(void)
{
BUG_ON(smp_processor_id() != boot_cpuid);
#ifdef CONFIG_PPC64

2
include/linux/smp.h
View file

@ -109,7 +109,7 @@ static inline void on_each_cpu_cond(smp_cond_func_t cond_func,
* Architecture specific boot CPU setup. Defined as empty weak function in
* init/main.c. Architectures can override it.
*/
void smp_prepare_boot_cpu(void);
void __init smp_prepare_boot_cpu(void);
#ifdef CONFIG_SMP

20
kernel/cpu.c
View file

@ -1808,6 +1808,7 @@ static int __init parallel_bringup_parse_param(char *arg)
}
early_param("cpuhp.parallel", parallel_bringup_parse_param);
#ifdef CONFIG_HOTPLUG_SMT
static inline bool cpuhp_smt_aware(void)
{
return cpu_smt_max_threads > 1;
@ -1817,6 +1818,21 @@ static inline const struct cpumask *cpuhp_get_primary_thread_mask(void)
{
return cpu_primary_thread_mask;
}
#else
static inline bool cpuhp_smt_aware(void)
{
return false;
}
static inline const struct cpumask *cpuhp_get_primary_thread_mask(void)
{
return cpu_none_mask;
}
#endif
bool __weak arch_cpuhp_init_parallel_bringup(void)
{
return true;
}
/*
* On architectures which have enabled parallel bringup this invokes all BP
@ -2689,9 +2705,7 @@ int cpuhp_smt_disable(enum cpuhp_smt_control ctrlval)
return ret;
}
/**
* Check if the core a CPU belongs to is online
*/
/* Check if the core a CPU belongs to is online */
#if !defined(topology_is_core_online)
static inline bool topology_is_core_online(unsigned int cpu)
{