| Message ID | 1389554441-27335-2-git-send-email-broonie@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
[adding Vincent in CC, questions related to SCHED MC macros] Minor comments below. On Sun, Jan 12, 2014 at 07:20:38PM +0000, Mark Brown wrote: > From: Mark Brown <broonie@linaro.org> > > Add basic CPU topology support to arm64, based on the existing pre-v8 > code and some work done by Mark Hambleton. This patch does not > implement any topology discovery support since that should be based on > information from firmware, it merely implements the scaffolding for > integration of topology support in the architecture. > > The goal is to separate the architecture hookup for providing topology > information from the DT parsing in order to ease review and avoid > blocking the architecture code (which will be built on by other work) > with the DT code review by providing something something simple > and basic. "something something", one something is enough. [...] > new file mode 100644 > index 000000000000..6f5270c65a6c > --- /dev/null > +++ b/arch/arm64/include/asm/topology.h > @@ -0,0 +1,39 @@ > +#ifndef __ASM_TOPOLOGY_H > +#define __ASM_TOPOLOGY_H > + > +#ifdef CONFIG_CPU_TOPOLOGY > + > +#include <linux/cpumask.h> > + > +struct cpu_topology { > + int thread_id; > + int core_id; > + int socket_id; Is there any reason why we can't rename socket_id to cluster_id ? It won't change our lives but at least we kind of know what it means in ARM world. > + cpumask_t thread_sibling; > + cpumask_t core_sibling; > +}; > + > +extern struct cpu_topology cpu_topology[NR_CPUS]; > + > +#define topology_physical_package_id(cpu) (cpu_topology[cpu].socket_id) > +#define topology_core_id(cpu) (cpu_topology[cpu].core_id) > +#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling) > +#define topology_thread_cpumask(cpu) (&cpu_topology[cpu].thread_sibling) > + > +#define mc_capable() (cpu_topology[0].socket_id != -1) > +#define smt_capable() (cpu_topology[0].thread_id != -1) Are the two macros above still required in the kernel ? I can't see any usage at present. Vincent, do you know why they were not removed in commit: 8e7fbcbc22c12414bcc9dfdd683637f58fb32759 I am certainly missing something. > +void init_cpu_topology(void); > +void store_cpu_topology(unsigned int cpuid); > +const struct cpumask *cpu_coregroup_mask(int cpu); > + > +#else > + > +static inline void init_cpu_topology(void) { } > +static inline void store_cpu_topology(unsigned int cpuid) { } > + > +#endif > + > +#include <asm-generic/topology.h> > + > +#endif /* _ASM_ARM_TOPOLOGY_H */ > diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile > index 2d4554b13410..252b62181532 100644 > --- a/arch/arm64/kernel/Makefile > +++ b/arch/arm64/kernel/Makefile > @@ -20,6 +20,7 @@ arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o > arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o > arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o > arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o > +arm64-obj-$(CONFIG_CPU_TOPOLOGY) += topology.o > > obj-y += $(arm64-obj-y) vdso/ > obj-m += $(arm64-obj-m) > diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c > index 1b7617ab499b..40e20efc13e6 100644 > --- a/arch/arm64/kernel/smp.c > +++ b/arch/arm64/kernel/smp.c > @@ -114,6 +114,11 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) > return ret; > } > > +static void __cpuinit smp_store_cpu_info(unsigned int cpuid) > +{ > + store_cpu_topology(cpuid); > +} __cpuinit has been (is being) removed from the kernel and probably should be removed from this definition too. > + > /* > * This is the secondary CPU boot entry. We're using this CPUs > * idle thread stack, but a set of temporary page tables. > @@ -152,6 +157,8 @@ asmlinkage void secondary_start_kernel(void) > */ > notify_cpu_starting(cpu); > > + smp_store_cpu_info(cpu); > + > /* > * OK, now it's safe to let the boot CPU continue. Wait for > * the CPU migration code to notice that the CPU is online > @@ -391,6 +398,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus) > int err; > unsigned int cpu, ncores = num_possible_cpus(); > > + init_cpu_topology(); > + > + smp_store_cpu_info(smp_processor_id()); > + > + Too many empty lines, one is enough. > /* > * are we trying to boot more cores than exist? > */ > diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c > new file mode 100644 > index 000000000000..980019fefeff > --- /dev/null > +++ b/arch/arm64/kernel/topology.c > @@ -0,0 +1,91 @@ > +/* > + * arch/arm64/kernel/topology.c > + * > + * Copyright (C) 2011,2013 Linaro Limited. > + * > + * Based on the arm32 version written by Vincent Guittot in turn based on > + * arch/sh/kernel/topology.c > + * > + * This file is subject to the terms and conditions of the GNU General Public > + * License. See the file "COPYING" in the main directory of this archive > + * for more details. > + */ > + > +#include <linux/cpu.h> > +#include <linux/cpumask.h> > +#include <linux/init.h> > +#include <linux/percpu.h> > +#include <linux/node.h> > +#include <linux/nodemask.h> > +#include <linux/sched.h> > + > +#include <asm/topology.h> I have already commented on this. If this patchset is completely merged, that is one thing, if it is not we are adding include files for nothing. If you have time, and there should be given that the set missed the merge window it would be nice to split the includes, I will not nitpick any longer though, so it is up to you. [...] > +/* > + * init_cpu_topology is called at boot when only one cpu is running > + * which prevent simultaneous write access to cpu_topology array > + */ > +void __init init_cpu_topology(void) > +{ > + unsigned int cpu; > + > + /* init core mask and power*/ > + for_each_possible_cpu(cpu) { > + struct cpu_topology *cpu_topo = &(cpu_topology[cpu]); You do not need brackets, &cpu_topology[cpu] will do. Lorenzo
On Mon, Jan 13, 2014 at 04:10:59PM +0000, Lorenzo Pieralisi wrote: > On Sun, Jan 12, 2014 at 07:20:38PM +0000, Mark Brown wrote: > > +struct cpu_topology { > > + int thread_id; > > + int core_id; > > + int socket_id; > Is there any reason why we can't rename socket_id to cluster_id ? It won't > change our lives but at least we kind of know what it means in ARM world. I really don't care, whatever you guys want. > > +#define mc_capable() (cpu_topology[0].socket_id != -1) > > +#define smt_capable() (cpu_topology[0].thread_id != -1) > Are the two macros above still required in the kernel ? I can't see any > usage at present. > > Vincent, do you know why they were not removed in commit: > > 8e7fbcbc22c12414bcc9dfdd683637f58fb32759 > > I am certainly missing something. They're defined by a bunch of other architectures (including x86). If I had to guess I'd say the architectures are still providing the information so we don't need to go round adding it again if someone comes up with a use for it in the core.
On 13 January 2014 17:10, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > [adding Vincent in CC, questions related to SCHED MC macros] > > Minor comments below. > > On Sun, Jan 12, 2014 at 07:20:38PM +0000, Mark Brown wrote: >> From: Mark Brown <broonie@linaro.org> >> >> Add basic CPU topology support to arm64, based on the existing pre-v8 >> code and some work done by Mark Hambleton. This patch does not >> implement any topology discovery support since that should be based on >> information from firmware, it merely implements the scaffolding for >> integration of topology support in the architecture. >> >> The goal is to separate the architecture hookup for providing topology >> information from the DT parsing in order to ease review and avoid >> blocking the architecture code (which will be built on by other work) >> with the DT code review by providing something something simple >> and basic. > > "something something", one something is enough. > > [...] > >> new file mode 100644 >> index 000000000000..6f5270c65a6c >> --- /dev/null >> +++ b/arch/arm64/include/asm/topology.h >> @@ -0,0 +1,39 @@ >> +#ifndef __ASM_TOPOLOGY_H >> +#define __ASM_TOPOLOGY_H >> + >> +#ifdef CONFIG_CPU_TOPOLOGY >> + >> +#include <linux/cpumask.h> >> + >> +struct cpu_topology { >> + int thread_id; >> + int core_id; >> + int socket_id; > > Is there any reason why we can't rename socket_id to cluster_id ? It won't > change our lives but at least we kind of know what it means in ARM world. > >> + cpumask_t thread_sibling; >> + cpumask_t core_sibling; >> +}; >> + >> +extern struct cpu_topology cpu_topology[NR_CPUS]; >> + >> +#define topology_physical_package_id(cpu) (cpu_topology[cpu].socket_id) >> +#define topology_core_id(cpu) (cpu_topology[cpu].core_id) >> +#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling) >> +#define topology_thread_cpumask(cpu) (&cpu_topology[cpu].thread_sibling) >> + >> +#define mc_capable() (cpu_topology[0].socket_id != -1) >> +#define smt_capable() (cpu_topology[0].thread_id != -1) > > Are the two macros above still required in the kernel ? I can't see any > usage at present. > > Vincent, do you know why they were not removed in commit: > > 8e7fbcbc22c12414bcc9dfdd683637f58fb32759 > > I am certainly missing something. I think it was not planned to be used only by the scheduler but since 8e7fbcbc22c12414bcc9dfdd683637f58fb32759, we have reach a situation where nobody use them for the moment. > >> +void init_cpu_topology(void); >> +void store_cpu_topology(unsigned int cpuid); >> +const struct cpumask *cpu_coregroup_mask(int cpu); >> + >> +#else >> + >> +static inline void init_cpu_topology(void) { } >> +static inline void store_cpu_topology(unsigned int cpuid) { } >> + >> +#endif >> + >> +#include <asm-generic/topology.h> >> + >> +#endif /* _ASM_ARM_TOPOLOGY_H */ >> diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile >> index 2d4554b13410..252b62181532 100644 >> --- a/arch/arm64/kernel/Makefile >> +++ b/arch/arm64/kernel/Makefile >> @@ -20,6 +20,7 @@ arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o >> arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o >> arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o >> arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o >> +arm64-obj-$(CONFIG_CPU_TOPOLOGY) += topology.o >> >> obj-y += $(arm64-obj-y) vdso/ >> obj-m += $(arm64-obj-m) >> diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c >> index 1b7617ab499b..40e20efc13e6 100644 >> --- a/arch/arm64/kernel/smp.c >> +++ b/arch/arm64/kernel/smp.c >> @@ -114,6 +114,11 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) >> return ret; >> } >> >> +static void __cpuinit smp_store_cpu_info(unsigned int cpuid) >> +{ >> + store_cpu_topology(cpuid); >> +} > > __cpuinit has been (is being) removed from the kernel and probably should > be removed from this definition too. > >> + >> /* >> * This is the secondary CPU boot entry. We're using this CPUs >> * idle thread stack, but a set of temporary page tables. >> @@ -152,6 +157,8 @@ asmlinkage void secondary_start_kernel(void) >> */ >> notify_cpu_starting(cpu); >> >> + smp_store_cpu_info(cpu); >> + >> /* >> * OK, now it's safe to let the boot CPU continue. Wait for >> * the CPU migration code to notice that the CPU is online >> @@ -391,6 +398,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus) >> int err; >> unsigned int cpu, ncores = num_possible_cpus(); >> >> + init_cpu_topology(); >> + >> + smp_store_cpu_info(smp_processor_id()); >> + >> + > > Too many empty lines, one is enough. > >> /* >> * are we trying to boot more cores than exist? >> */ >> diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c >> new file mode 100644 >> index 000000000000..980019fefeff >> --- /dev/null >> +++ b/arch/arm64/kernel/topology.c >> @@ -0,0 +1,91 @@ >> +/* >> + * arch/arm64/kernel/topology.c >> + * >> + * Copyright (C) 2011,2013 Linaro Limited. >> + * >> + * Based on the arm32 version written by Vincent Guittot in turn based on >> + * arch/sh/kernel/topology.c >> + * >> + * This file is subject to the terms and conditions of the GNU General Public >> + * License. See the file "COPYING" in the main directory of this archive >> + * for more details. >> + */ >> + >> +#include <linux/cpu.h> >> +#include <linux/cpumask.h> >> +#include <linux/init.h> >> +#include <linux/percpu.h> >> +#include <linux/node.h> >> +#include <linux/nodemask.h> >> +#include <linux/sched.h> >> + >> +#include <asm/topology.h> > > I have already commented on this. If this patchset is completely merged, > that is one thing, if it is not we are adding include files for nothing. > If you have time, and there should be given that the set missed the > merge window it would be nice to split the includes, I will not nitpick > any longer though, so it is up to you. > > [...] > >> +/* >> + * init_cpu_topology is called at boot when only one cpu is running >> + * which prevent simultaneous write access to cpu_topology array >> + */ >> +void __init init_cpu_topology(void) >> +{ >> + unsigned int cpu; >> + >> + /* init core mask and power*/ >> + for_each_possible_cpu(cpu) { >> + struct cpu_topology *cpu_topo = &(cpu_topology[cpu]); > > You do not need brackets, &cpu_topology[cpu] will do. > > Lorenzo >
On Mon, Jan 13, 2014 at 04:44:06PM +0000, Vincent Guittot wrote: [...] > >> +extern struct cpu_topology cpu_topology[NR_CPUS]; > >> + > >> +#define topology_physical_package_id(cpu) (cpu_topology[cpu].socket_id) > >> +#define topology_core_id(cpu) (cpu_topology[cpu].core_id) > >> +#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling) > >> +#define topology_thread_cpumask(cpu) (&cpu_topology[cpu].thread_sibling) > >> + > >> +#define mc_capable() (cpu_topology[0].socket_id != -1) > >> +#define smt_capable() (cpu_topology[0].thread_id != -1) > > > > Are the two macros above still required in the kernel ? I can't see any > > usage at present. > > > > Vincent, do you know why they were not removed in commit: > > > > 8e7fbcbc22c12414bcc9dfdd683637f58fb32759 > > > > I am certainly missing something. > > I think it was not planned to be used only by the scheduler but since > 8e7fbcbc22c12414bcc9dfdd683637f58fb32759, we have reach a situation > where nobody use them for the moment. Ok, we can add the macros and eventually remove all of them in a later patch if we think they must go then. Lorenzo
On Mon, Jan 13, 2014 at 04:30:45PM +0000, Mark Brown wrote: > On Mon, Jan 13, 2014 at 04:10:59PM +0000, Lorenzo Pieralisi wrote: > > On Sun, Jan 12, 2014 at 07:20:38PM +0000, Mark Brown wrote: > > > > +struct cpu_topology { > > > + int thread_id; > > > + int core_id; > > > + int socket_id; > > > Is there any reason why we can't rename socket_id to cluster_id ? It won't > > change our lives but at least we kind of know what it means in ARM world. > > I really don't care, whatever you guys want. s/socket_id/cluster_id unless we have a compelling reason to keep the socket_id naming, I do not see it, given that cpu_topology is arch specific anyway. socket_id means really nothing in ARM world. Again, Vincent if you see a compelling reason to keep socket_id as in arm32 that I am missing please shout. > > > > +#define mc_capable() (cpu_topology[0].socket_id != -1) > > > +#define smt_capable() (cpu_topology[0].thread_id != -1) > > > Are the two macros above still required in the kernel ? I can't see any > > usage at present. > > > > Vincent, do you know why they were not removed in commit: > > > > 8e7fbcbc22c12414bcc9dfdd683637f58fb32759 > > > > I am certainly missing something. > > They're defined by a bunch of other architectures (including x86). If I > had to guess I'd say the architectures are still providing the > information so we don't need to go round adding it again if someone > comes up with a use for it in the core. Yes, let's keep the macros, just wanted to make sure I got it right. Lorenzo
On 13 January 2014 18:44, Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> wrote: > On Mon, Jan 13, 2014 at 04:30:45PM +0000, Mark Brown wrote: >> On Mon, Jan 13, 2014 at 04:10:59PM +0000, Lorenzo Pieralisi wrote: >> > On Sun, Jan 12, 2014 at 07:20:38PM +0000, Mark Brown wrote: >> >> > > +struct cpu_topology { >> > > + int thread_id; >> > > + int core_id; >> > > + int socket_id; >> >> > Is there any reason why we can't rename socket_id to cluster_id ? It won't >> > change our lives but at least we kind of know what it means in ARM world. >> >> I really don't care, whatever you guys want. > > s/socket_id/cluster_id > > unless we have a compelling reason to keep the socket_id naming, I do > not see it, given that cpu_topology is arch specific anyway. > > socket_id means really nothing in ARM world. > > Again, Vincent if you see a compelling reason to keep socket_id as in arm32 > that I am missing please shout. I don't have any compellingreason, i have just used the same name than other platform. Vincent > >> >> > > +#define mc_capable() (cpu_topology[0].socket_id != -1) >> > > +#define smt_capable() (cpu_topology[0].thread_id != -1) >> >> > Are the two macros above still required in the kernel ? I can't see any >> > usage at present. >> > >> > Vincent, do you know why they were not removed in commit: >> > >> > 8e7fbcbc22c12414bcc9dfdd683637f58fb32759 >> > >> > I am certainly missing something. >> >> They're defined by a bunch of other architectures (including x86). If I >> had to guess I'd say the architectures are still providing the >> information so we don't need to go round adding it again if someone >> comes up with a use for it in the core. > > Yes, let's keep the macros, just wanted to make sure I got it right. > > Lorenzo >
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index dd4327f09ba4..02309c3eec33 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -163,6 +163,30 @@ config SMP If you don't know what to do here, say N. +config CPU_TOPOLOGY + bool "Support CPU topology definition" + depends on SMP + default y + help + Support CPU topology definition, based on configuration + provided by the firmware. + +config SCHED_MC + bool "Multi-core scheduler support" + depends on CPU_TOPOLOGY + help + Multi-core scheduler support improves the CPU scheduler's decision + making when dealing with multi-core CPU chips at a cost of slightly + increased overhead in some places. If unsure say N here. + +config SCHED_SMT + bool "SMT scheduler support" + depends on CPU_TOPOLOGY + help + Improves the CPU scheduler's decision making when dealing with + MultiThreading at a cost of slightly increased overhead in some + places. If unsure say N here. + config NR_CPUS int "Maximum number of CPUs (2-32)" range 2 32 diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h new file mode 100644 index 000000000000..6f5270c65a6c --- /dev/null +++ b/arch/arm64/include/asm/topology.h @@ -0,0 +1,39 @@ +#ifndef __ASM_TOPOLOGY_H +#define __ASM_TOPOLOGY_H + +#ifdef CONFIG_CPU_TOPOLOGY + +#include <linux/cpumask.h> + +struct cpu_topology { + int thread_id; + int core_id; + int socket_id; + cpumask_t thread_sibling; + cpumask_t core_sibling; +}; + +extern struct cpu_topology cpu_topology[NR_CPUS]; + +#define topology_physical_package_id(cpu) (cpu_topology[cpu].socket_id) +#define topology_core_id(cpu) (cpu_topology[cpu].core_id) +#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling) +#define topology_thread_cpumask(cpu) (&cpu_topology[cpu].thread_sibling) + +#define mc_capable() (cpu_topology[0].socket_id != -1) +#define smt_capable() (cpu_topology[0].thread_id != -1) + +void init_cpu_topology(void); +void store_cpu_topology(unsigned int cpuid); +const struct cpumask *cpu_coregroup_mask(int cpu); + +#else + +static inline void init_cpu_topology(void) { } +static inline void store_cpu_topology(unsigned int cpuid) { } + +#endif + +#include <asm-generic/topology.h> + +#endif /* _ASM_ARM_TOPOLOGY_H */ diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index 2d4554b13410..252b62181532 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -20,6 +20,7 @@ arm64-obj-$(CONFIG_HAVE_HW_BREAKPOINT)+= hw_breakpoint.o arm64-obj-$(CONFIG_EARLY_PRINTK) += early_printk.o arm64-obj-$(CONFIG_ARM64_CPU_SUSPEND) += sleep.o suspend.o arm64-obj-$(CONFIG_JUMP_LABEL) += jump_label.o +arm64-obj-$(CONFIG_CPU_TOPOLOGY) += topology.o obj-y += $(arm64-obj-y) vdso/ obj-m += $(arm64-obj-m) diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c index 1b7617ab499b..40e20efc13e6 100644 --- a/arch/arm64/kernel/smp.c +++ b/arch/arm64/kernel/smp.c @@ -114,6 +114,11 @@ int __cpu_up(unsigned int cpu, struct task_struct *idle) return ret; } +static void __cpuinit smp_store_cpu_info(unsigned int cpuid) +{ + store_cpu_topology(cpuid); +} + /* * This is the secondary CPU boot entry. We're using this CPUs * idle thread stack, but a set of temporary page tables. @@ -152,6 +157,8 @@ asmlinkage void secondary_start_kernel(void) */ notify_cpu_starting(cpu); + smp_store_cpu_info(cpu); + /* * OK, now it's safe to let the boot CPU continue. Wait for * the CPU migration code to notice that the CPU is online @@ -391,6 +398,11 @@ void __init smp_prepare_cpus(unsigned int max_cpus) int err; unsigned int cpu, ncores = num_possible_cpus(); + init_cpu_topology(); + + smp_store_cpu_info(smp_processor_id()); + + /* * are we trying to boot more cores than exist? */ diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c new file mode 100644 index 000000000000..980019fefeff --- /dev/null +++ b/arch/arm64/kernel/topology.c @@ -0,0 +1,91 @@ +/* + * arch/arm64/kernel/topology.c + * + * Copyright (C) 2011,2013 Linaro Limited. + * + * Based on the arm32 version written by Vincent Guittot in turn based on + * arch/sh/kernel/topology.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include <linux/cpu.h> +#include <linux/cpumask.h> +#include <linux/init.h> +#include <linux/percpu.h> +#include <linux/node.h> +#include <linux/nodemask.h> +#include <linux/sched.h> + +#include <asm/topology.h> + +/* + * cpu topology table + */ +struct cpu_topology cpu_topology[NR_CPUS]; +EXPORT_SYMBOL_GPL(cpu_topology); + +const struct cpumask *cpu_coregroup_mask(int cpu) +{ + return &cpu_topology[cpu].core_sibling; +} + +static void update_siblings_masks(unsigned int cpuid) +{ + struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid]; + int cpu; + + /* update core and thread sibling masks */ + for_each_possible_cpu(cpu) { + cpu_topo = &cpu_topology[cpu]; + + if (cpuid_topo->socket_id != cpu_topo->socket_id) + continue; + + cpumask_set_cpu(cpuid, &cpu_topo->core_sibling); + if (cpu != cpuid) + cpumask_set_cpu(cpu, &cpuid_topo->core_sibling); + + if (cpuid_topo->core_id != cpu_topo->core_id) + continue; + + cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling); + if (cpu != cpuid) + cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling); + } + smp_wmb(); +} + +void store_cpu_topology(unsigned int cpuid) +{ + struct cpu_topology *cpuid_topo = &cpu_topology[cpuid]; + + /* DT should have been parsed by the time we get here */ + if (cpuid_topo->core_id == -1) + pr_info("CPU%u: No topology information configured\n", cpuid); + else + update_siblings_masks(cpuid); +} + +/* + * init_cpu_topology is called at boot when only one cpu is running + * which prevent simultaneous write access to cpu_topology array + */ +void __init init_cpu_topology(void) +{ + unsigned int cpu; + + /* init core mask and power*/ + for_each_possible_cpu(cpu) { + struct cpu_topology *cpu_topo = &(cpu_topology[cpu]); + + cpu_topo->thread_id = -1; + cpu_topo->core_id = -1; + cpu_topo->socket_id = -1; + cpumask_clear(&cpu_topo->core_sibling); + cpumask_clear(&cpu_topo->thread_sibling); + } + smp_wmb(); +}