[PATCH RFC v3 05/21] ACPI: Rename ACPI_HOTPLUG_CPU to include 'present'

From: Oracle
Date: Wed Dec 13 2023 - 07:49:50 EST

From: James Morse <james.morse@xxxxxxx>

The code behind ACPI_HOTPLUG_CPU allows a not-present CPU to become
present. This isn't the only use of HOTPLUG_CPU. On arm64 and riscv
CPUs can be taken offline as a power saving measure.

On arm64 an offline CPU may be disabled by firmware, preventing it from
being brought back online, but it remains present throughout.

Adding code to prevent user-space trying to online these disabled CPUs
needs some additional terminology.

Rename the Kconfig symbol CONFIG_ACPI_HOTPLUG_PRESENT_CPU to reflect
that it makes possible CPUs present.

HOTPLUG_CPU is untouched as this is only about the ACPI mechanism.

Signed-off-by: James Morse <james.morse@xxxxxxx>
Tested-by: Miguel Luis <miguel.luis@xxxxxxxxxx>
Tested-by: Vishnu Pajjuri <vishnu@xxxxxxxxxxxxxxxxxxxxxx>
Tested-by: Jianyong Wu <jianyong.wu@xxxxxxx>
Signed-off-by: Russell King (Oracle) <rmk+kernel@xxxxxxxxxxxxxxx>
---
Changes since RFC v2:
* Add Loongarch update
Changes since RFC v3:
* Dropped ia64 changes
---
arch/loongarch/Kconfig | 2 +-
arch/loongarch/configs/loongson3_defconfig | 2 +-
arch/loongarch/kernel/acpi.c | 4 ++--
arch/x86/Kconfig | 2 +-
arch/x86/kernel/acpi/boot.c | 4 ++--
drivers/acpi/Kconfig | 4 ++--
drivers/acpi/acpi_processor.c | 10 +++++-----
include/linux/acpi.h | 6 +++---
8 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/arch/loongarch/Kconfig b/arch/loongarch/Kconfig
index 15d05dd2b7f3..b1e87b90468d 100644
--- a/arch/loongarch/Kconfig
+++ b/arch/loongarch/Kconfig
@@ -5,7 +5,7 @@ config LOONGARCH
select ACPI
select ACPI_GENERIC_GSI if ACPI
select ACPI_MCFG if ACPI
- select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
+ select ACPI_HOTPLUG_PRESENT_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
select ACPI_PPTT if ACPI
select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
select ARCH_BINFMT_ELF_STATE
diff --git a/arch/loongarch/configs/loongson3_defconfig b/arch/loongarch/configs/loongson3_defconfig
index 33795e4a5bd6..85d37b143077 100644
--- a/arch/loongarch/configs/loongson3_defconfig
+++ b/arch/loongarch/configs/loongson3_defconfig
@@ -59,7 +59,7 @@ CONFIG_ACPI_SPCR_TABLE=y
CONFIG_ACPI_TAD=y
CONFIG_ACPI_DOCK=y
CONFIG_ACPI_IPMI=m
-CONFIG_ACPI_HOTPLUG_CPU=y
+CONFIG_ACPI_HOTPLUG_PRESENT_CPU=y
CONFIG_ACPI_PCI_SLOT=y
CONFIG_ACPI_HOTPLUG_MEMORY=y
CONFIG_EFI_ZBOOT=y
diff --git a/arch/loongarch/kernel/acpi.c b/arch/loongarch/kernel/acpi.c
index 8e00a754e548..dfa56119b56f 100644
--- a/arch/loongarch/kernel/acpi.c
+++ b/arch/loongarch/kernel/acpi.c
@@ -288,7 +288,7 @@ void __init arch_reserve_mem_area(acpi_physical_address addr, size_t size)
memblock_reserve(addr, size);
}

-#ifdef CONFIG_ACPI_HOTPLUG_CPU
+#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU

#include <acpi/processor.h>

@@ -340,4 +340,4 @@ int acpi_unmap_cpu(int cpu)
}
EXPORT_SYMBOL(acpi_unmap_cpu);

-#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+#endif /* CONFIG_ACPI_HOTPLUG_PRESENT_CPU */
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8330c4ac26b3..64fc7c475ab0 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -59,7 +59,7 @@ config X86
#
select ACPI_LEGACY_TABLES_LOOKUP if ACPI
select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
- select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
+ select ACPI_HOTPLUG_PRESENT_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
select ARCH_32BIT_OFF_T if X86_32
select ARCH_CLOCKSOURCE_INIT
select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
diff --git a/arch/x86/kernel/acpi/boot.c b/arch/x86/kernel/acpi/boot.c
index 1a0dd80d81ac..33d259ddd188 100644
--- a/arch/x86/kernel/acpi/boot.c
+++ b/arch/x86/kernel/acpi/boot.c
@@ -826,7 +826,7 @@ static void __init acpi_set_irq_model_ioapic(void)
/*
* ACPI based hotplug support for CPU
*/
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
+#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU
#include <acpi/processor.h>

static int acpi_map_cpu2node(acpi_handle handle, int cpu, int physid)
@@ -875,7 +875,7 @@ int acpi_unmap_cpu(int cpu)
return (0);
}
EXPORT_SYMBOL(acpi_unmap_cpu);
-#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+#endif /* CONFIG_ACPI_HOTPLUG_PRESENT_CPU */

int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
{
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index a3acfc750fce..9c5a43d0aff4 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -306,7 +306,7 @@ config ACPI_IPMI
To compile this driver as a module, choose M here:
the module will be called as acpi_ipmi.

-config ACPI_HOTPLUG_CPU
+config ACPI_HOTPLUG_PRESENT_CPU
bool
depends on ACPI_PROCESSOR && HOTPLUG_CPU
select ACPI_CONTAINER
@@ -400,7 +400,7 @@ config ACPI_PCI_SLOT

config ACPI_CONTAINER
bool "Container and Module Devices"
- default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_CPU)
+ default (ACPI_HOTPLUG_MEMORY || ACPI_HOTPLUG_PRESENT_CPU)
help
This driver supports ACPI Container and Module devices (IDs
ACPI0004, PNP0A05, and PNP0A06).
diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index e7ed4730cbbe..c8e960ff0aca 100644
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -183,7 +183,7 @@ static void __init acpi_pcc_cpufreq_init(void) {}
#endif /* CONFIG_X86 */

/* Initialization */
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
+#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU
static int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
unsigned long long sta;
@@ -228,7 +228,7 @@ static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
return -ENODEV;
}
-#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+#endif /* CONFIG_ACPI_HOTPLUG_PRESENT_CPU */

static int acpi_processor_get_info(struct acpi_device *device)
{
@@ -461,7 +461,7 @@ static int acpi_processor_add(struct acpi_device *device,
return result;
}

-#ifdef CONFIG_ACPI_HOTPLUG_CPU
+#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU
/* Removal */
static void acpi_processor_remove(struct acpi_device *device)
{
@@ -505,7 +505,7 @@ static void acpi_processor_remove(struct acpi_device *device)
free_cpumask_var(pr->throttling.shared_cpu_map);
kfree(pr);
}
-#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+#endif /* CONFIG_ACPI_HOTPLUG_PRESENT_CPU */

#ifdef CONFIG_ARCH_MIGHT_HAVE_ACPI_PDC
bool __init processor_physically_present(acpi_handle handle)
@@ -630,7 +630,7 @@ static const struct acpi_device_id processor_device_ids[] = {
static struct acpi_scan_handler processor_handler = {
.ids = processor_device_ids,
.attach = acpi_processor_add,
-#ifdef CONFIG_ACPI_HOTPLUG_CPU
+#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU
.detach = acpi_processor_remove,
#endif
.hotplug = {
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 4db54e928b36..36071bc11acd 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -301,12 +301,12 @@ static inline int acpi_processor_evaluate_cst(acpi_handle handle, u32 cpu,
}
#endif

-#ifdef CONFIG_ACPI_HOTPLUG_CPU
+#ifdef CONFIG_ACPI_HOTPLUG_PRESENT_CPU
/* Arch dependent functions for cpu hotplug support */
int acpi_map_cpu(acpi_handle handle, phys_cpuid_t physid, u32 acpi_id,
int *pcpu);
int acpi_unmap_cpu(int cpu);
-#endif /* CONFIG_ACPI_HOTPLUG_CPU */
+#endif /* CONFIG_ACPI_HOTPLUG_PRESENT_CPU */

#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr);
@@ -629,7 +629,7 @@ static inline u32 acpi_osc_ctx_get_cxl_control(struct acpi_osc_context *context)
#define ACPI_GSB_ACCESS_ATTRIB_RAW_PROCESS 0x0000000F

/* Enable _OST when all relevant hotplug operations are enabled */
-#if defined(CONFIG_ACPI_HOTPLUG_CPU) && \
+#if defined(CONFIG_ACPI_HOTPLUG_PRESENT_CPU) && \
defined(CONFIG_ACPI_HOTPLUG_MEMORY) && \
defined(CONFIG_ACPI_CONTAINER)
#define ACPI_HOTPLUG_OST
--
2.30.2