From: James Morse james.morse@arm.com
mainline inclusion from mainline-v6.8-rc1 commit 0949dd96dffec39683c6066cf8d0877cebc321ec category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I8XMTL CVE: NA
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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 Reviewed-by: Jonathan Cameron Jonathan.Cameron@huawei.com Reviewed-by: Thomas Gleixner tglx@linutronix.de Link: https://lore.kernel.org/r/E1r5R3B-00Csz6-Uh@rmk-PC.armlinux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: liwei liwei728@huawei.com --- drivers/base/cpu.c | 14 ++++++++++---- 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 13359712e069..22625695f310 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 eb768a866fe3..e117c06e0c6b 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