diff options
| author | James Morse <james.morse@arm.com> | 2021-03-29 12:37:04 +0100 |
|---|---|---|
| committer | Russell King (Oracle) <rmk+kernel@armlinux.org.uk> | 2023-11-14 10:00:09 +0000 |
| commit | 7c22a6058c7ae941f601cacf0890af0d1fe6e64b (patch) | |
| tree | 0d5dab40a0e571c5f2526472af5362c35fcdeb7a | |
| parent | b644640762f3d98513b7c0969dced85378d12460 (diff) | |
drivers: base: Allow parts of GENERIC_CPU_DEVICES to be overridden
Architectures often have extra per-cpu work that needs doing
before a CPU is registered, often to determine if a CPU is
hotpluggable.
To allow the ACPI architectures to use GENERIC_CPU_DEVICES, move
the cpu_register() call into arch_register_cpu(), which is made __weak
so architectures with extra work can override it.
This aligns with the way x86, ia64 and loongarch register hotplug CPUs
when they become present.
Signed-off-by: James Morse <james.morse@arm.com>
Reviewed-by: Shaoqin Huang <shahuang@redhat.com>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
---
Changes since RFC:
* Dropped __init from x86/ia64 arch_register_cpu()
Changes since RFC v2:
* Dropped unnecessary Loongarch asm/cpu.h changes
| -rw-r--r-- | drivers/base/cpu.c | 14 | ||||
| -rw-r--r-- | include/linux/cpu.h | 4 |
2 files changed, 14 insertions, 4 deletions
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c index 34b48f660b6b..579064fda97b 100644 --- a/drivers/base/cpu.c +++ b/drivers/base/cpu.c @@ -525,19 +525,25 @@ bool cpu_is_hotpluggable(unsigned int cpu) EXPORT_SYMBOL_GPL(cpu_is_hotpluggable); #ifdef CONFIG_GENERIC_CPU_DEVICES -static DEFINE_PER_CPU(struct cpu, cpu_devices); +DEFINE_PER_CPU(struct cpu, cpu_devices); + +int __weak arch_register_cpu(int cpu) +{ + return register_cpu(&per_cpu(cpu_devices, cpu), cpu); +} #endif static void __init cpu_dev_register_generic(void) { -#ifdef CONFIG_GENERIC_CPU_DEVICES int i; + if (!IS_ENABLED(CONFIG_GENERIC_CPU_DEVICES)) + return; + for_each_present_cpu(i) { - if (register_cpu(&per_cpu(cpu_devices, i), i)) + if (arch_register_cpu(i)) panic("Failed to register CPU device"); } -#endif } #ifdef CONFIG_GENERIC_CPU_VULNERABILITIES diff --git a/include/linux/cpu.h b/include/linux/cpu.h index fc8094419084..1e982d63eae8 100644 --- a/include/linux/cpu.h +++ b/include/linux/cpu.h @@ -88,6 +88,10 @@ extern ssize_t arch_cpu_probe(const char *, size_t); extern ssize_t arch_cpu_release(const char *, size_t); #endif +#ifdef CONFIG_GENERIC_CPU_DEVICES +DECLARE_PER_CPU(struct cpu, cpu_devices); +#endif + /* * These states are not related to the core CPU hotplug mechanism. They are * used by various (sub)architectures to track internal state |