| Message ID | E1r0JLv-00CTy1-Gq@rmk-PC.armlinux.org.uk (mailing list archive) |
|---|---|
| State | RFC, archived |
| Headers | show |
| Series | Initial cleanups for vCPU hotplug | expand |
On 11/7/23 20:30, Russell King (Oracle) wrote: > From: James Morse <james.morse@arm.com> > > Now that GENERIC_CPU_DEVICES calls arch_register_cpu(), which can be > overridden by the arch code, switch over to this to allow common code > to choose when the register_cpu() call is made. > > x86's struct cpus come from struct x86_cpu, which has no other members > or users. Remove this and use the version defined by common code. > > This is an intermediate step to the logic being moved to drivers/acpi, > where GENERIC_CPU_DEVICES will do the work when booting with acpi=off. > > This patch also has the effect of moving the registration of CPUs from > subsys to driver core initialisation, prior to any initcalls running. > > Signed-off-by: James Morse <james.morse@arm.com> > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> > ---- > Changes since RFC: > * Fixed the second copy of arch_register_cpu() used for non-hotplug > Changes since RFC v2: > * Remove duplicate of the weak generic arch_register_cpu(), spotted > by Jonathan Cameron. Add note about initialisation order change. > Changes since RFC v3: > * Adapt to removal of EXPORT_SYMBOL()s > --- > arch/x86/Kconfig | 1 + > arch/x86/include/asm/cpu.h | 4 ---- > arch/x86/kernel/topology.c | 27 ++++----------------------- > 3 files changed, 5 insertions(+), 27 deletions(-) > Reviewed-by: Gavin Shan <gshan@redhat.com>
On Tue, 07 Nov 2023 10:30:35 +0000 Russell King <rmk+kernel@armlinux.org.uk> wrote: > From: James Morse <james.morse@arm.com> > > Now that GENERIC_CPU_DEVICES calls arch_register_cpu(), which can be > overridden by the arch code, switch over to this to allow common code > to choose when the register_cpu() call is made. > > x86's struct cpus come from struct x86_cpu, which has no other members > or users. Remove this and use the version defined by common code. > > This is an intermediate step to the logic being moved to drivers/acpi, > where GENERIC_CPU_DEVICES will do the work when booting with acpi=off. > > This patch also has the effect of moving the registration of CPUs from > subsys to driver core initialisation, prior to any initcalls running. > > Signed-off-by: James Morse <james.morse@arm.com> > Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> In perfect world, I'd have liked the structure squash done as a precursor as then the patch would have been a little less noisy. However, sometimes it's just not worth the effort. Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index dbdcfc708369..8330c4ac26b3 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -148,6 +148,7 @@ config X86 select GENERIC_CLOCKEVENTS_MIN_ADJUST select GENERIC_CMOS_UPDATE select GENERIC_CPU_AUTOPROBE + select GENERIC_CPU_DEVICES select GENERIC_CPU_VULNERABILITIES select GENERIC_EARLY_IOREMAP select GENERIC_ENTRY diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index fecc4fe1d68a..f8f9a9b79395 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -23,10 +23,6 @@ static inline void prefill_possible_map(void) {} #endif /* CONFIG_SMP */ -struct x86_cpu { - struct cpu cpu; -}; - #ifdef CONFIG_HOTPLUG_CPU extern void soft_restart_cpu(void); #endif diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c index fcb62cfdf946..c2ed3145a93b 100644 --- a/arch/x86/kernel/topology.c +++ b/arch/x86/kernel/topology.c @@ -35,36 +35,17 @@ #include <asm/io_apic.h> #include <asm/cpu.h> -static DEFINE_PER_CPU(struct x86_cpu, cpu_devices); - #ifdef CONFIG_HOTPLUG_CPU int arch_register_cpu(int cpu) { - struct x86_cpu *xc = per_cpu_ptr(&cpu_devices, cpu); + struct cpu *c = per_cpu_ptr(&cpu_devices, cpu); - xc->cpu.hotpluggable = cpu > 0; - return register_cpu(&xc->cpu, cpu); + c->hotpluggable = cpu > 0; + return register_cpu(c, cpu); } void arch_unregister_cpu(int num) { - unregister_cpu(&per_cpu(cpu_devices, num).cpu); -} -#else /* CONFIG_HOTPLUG_CPU */ - -int __init arch_register_cpu(int num) -{ - return register_cpu(&per_cpu(cpu_devices, num).cpu, num); + unregister_cpu(&per_cpu(cpu_devices, num)); } #endif /* CONFIG_HOTPLUG_CPU */ - -static int __init topology_init(void) -{ - int i; - - for_each_present_cpu(i) - arch_register_cpu(i); - - return 0; -} -subsys_initcall(topology_init);