diff options
author | James Morse <james.morse@arm.com> | 2021-07-02 14:50:39 +0100 |
---|---|---|
committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2023-10-12 10:56:36 +0100 |
commit | ad6adc44193904991ad05129f72a8fa877c40947 (patch) | |
tree | a21a885c3334167158d0f845c369663222859b46 | |
parent | 94f6f0550c625fab1f373bb86a6669b45e9748b3 (diff) |
ACPI: Move ACPI_HOTPLUG_CPU to be enabled per architecture
arm64 doesn't support physical hotadd of CPUs that were not present at boot.
Much of the platform description is in static tables which do not have
update methods. arm64 does support HOTPLUG_CPU, which is backed by a
firmware interface to turn CPUs on and off.
acpi_processor_hotadd_init() and acpi_processor_remove() are for adding
and removing CPUs that were not present at boot. arm64 systems that do this
are not supported as there is currently insufficient information in the
platform description. (e.g. did the GICR get removed too?)
arm64 currently relies on the MADT enabled flag check in map_gicc_mpidr()
to prevent CPUs that were not described as present at boot from being
added to the system. Adding support for virtual CPU hotplug (where the
vCPUs have been present the whole time) would require this check to be
removed, possibly allowing physical CPUs to be added.
Disable ACPI_HOTPLUG_CPU for arm64 by removing 'default y' and selecting
it on the other three ACPI architectures. This allows the weak definitions
of some symbols to be removed.
Signed-off-by: James Morse <james.morse@arm.com>
---
Changes since RFC:
* Expanded x86 conditions to avoid ACPI_HOTPLUG_CPU being enabled when
HOTPLUG_CPU isn't.
-rw-r--r-- | arch/ia64/Kconfig | 1 | ||||
-rw-r--r-- | arch/loongarch/Kconfig | 1 | ||||
-rw-r--r-- | arch/loongarch/include/asm/cpu.h | 7 | ||||
-rw-r--r-- | arch/x86/Kconfig | 1 | ||||
-rw-r--r-- | drivers/acpi/Kconfig | 1 | ||||
-rw-r--r-- | drivers/acpi/acpi_processor.c | 18 |
6 files changed, 10 insertions, 19 deletions
diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig index 53faa122b0f4..3334618ad1f8 100644 --- a/arch/ia64/Kconfig +++ b/arch/ia64/Kconfig @@ -16,6 +16,7 @@ config IA64 select ARCH_MIGHT_HAVE_PC_PARPORT select ARCH_MIGHT_HAVE_PC_SERIO select ACPI + select ACPI_HOTPLUG_CPU if ACPI select ACPI_NUMA if NUMA select ARCH_ENABLE_MEMORY_HOTPLUG select ARCH_ENABLE_MEMORY_HOTREMOVE diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig index e14396a2ddcb..a9492b9a4248 100644 --- a/arch/loongarch/Kconfig +++ b/arch/loongarch/Kconfig @@ -4,6 +4,7 @@ config LOONGARCH default y select ACPI select ACPI_GENERIC_GSI if ACPI + select ACPI_HOTPLUG_CPU if ACPI select ACPI_MCFG if ACPI select ACPI_PPTT if ACPI select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI diff --git a/arch/loongarch/include/asm/cpu.h b/arch/loongarch/include/asm/cpu.h index 48b9f7168bcc..9be65d86aba6 100644 --- a/arch/loongarch/include/asm/cpu.h +++ b/arch/loongarch/include/asm/cpu.h @@ -128,4 +128,11 @@ enum cpu_type_enum { #define LOONGARCH_CPU_HYPERVISOR BIT_ULL(CPU_FEATURE_HYPERVISOR) #define LOONGARCH_CPU_PTW BIT_ULL(CPU_FEATURE_PTW) +#if !defined(__ASSEMBLY__) +#ifdef CONFIG_HOTPLUG_CPU +extern int arch_register_cpu(int num); +extern void arch_unregister_cpu(int); +#endif +#endif /* ! __ASSEMBLY__ */ + #endif /* _ASM_CPU_H */ diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 66bfabae8814..671e8fda9686 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -60,6 +60,7 @@ config X86 # select ACPI_LEGACY_TABLES_LOOKUP if ACPI select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI + select ACPI_HOTPLUG_CPU if ACPI && HOTPLUG_CPU select ARCH_32BIT_OFF_T if X86_32 select ARCH_CLOCKSOURCE_INIT select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index cee82b473dc5..8456d48ba702 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -309,7 +309,6 @@ config ACPI_HOTPLUG_CPU bool depends on ACPI_PROCESSOR && HOTPLUG_CPU select ACPI_CONTAINER - default y config ACPI_PROCESSOR_AGGREGATOR tristate "Processor Aggregator" diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c index c711db8a9c33..c0839bcf78c1 100644 --- a/drivers/acpi/acpi_processor.c +++ b/drivers/acpi/acpi_processor.c @@ -183,24 +183,6 @@ static void __init acpi_pcc_cpufreq_init(void) {} /* Initialization */ #ifdef CONFIG_ACPI_HOTPLUG_CPU -int __weak acpi_map_cpu(acpi_handle handle, - phys_cpuid_t physid, u32 acpi_id, int *pcpu) -{ - return -ENODEV; -} - -int __weak acpi_unmap_cpu(int cpu) -{ - return -ENODEV; -} - -int __weak arch_register_cpu(int cpu) -{ - return -ENODEV; -} - -void __weak arch_unregister_cpu(int cpu) {} - static int acpi_processor_hotadd_init(struct acpi_processor *pr) { unsigned long long sta; |