From: Thomas Gleixner Date: Fri, 12 May 2023 21:07:48 +0000 (+0200) Subject: x86/apic: Provide cpu_primary_thread mask X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=f54d4434c281f38b975d58de47adeca671beff4f;p=linux.git x86/apic: Provide cpu_primary_thread mask Make the primary thread tracking CPU mask based in preparation for simpler handling of parallel bootup. Signed-off-by: Thomas Gleixner Signed-off-by: Peter Zijlstra (Intel) Tested-by: Michael Kelley Tested-by: Oleksandr Natalenko Tested-by: Helge Deller # parisc Tested-by: Guilherme G. Piccoli # Steam Deck Link: https://lore.kernel.org/r/20230512205257.186599880@linutronix.de --- diff --git a/arch/x86/include/asm/apic.h b/arch/x86/include/asm/apic.h index dc50ed7db4476..030f5fb1daaf1 100644 --- a/arch/x86/include/asm/apic.h +++ b/arch/x86/include/asm/apic.h @@ -506,10 +506,8 @@ extern int default_check_phys_apicid_present(int phys_apicid); #endif /* CONFIG_X86_LOCAL_APIC */ #ifdef CONFIG_SMP -bool apic_id_is_primary_thread(unsigned int id); void apic_smt_update(void); #else -static inline bool apic_id_is_primary_thread(unsigned int id) { return false; } static inline void apic_smt_update(void) { } #endif diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h index 2ba57588e937f..caf41c4869a0e 100644 --- a/arch/x86/include/asm/topology.h +++ b/arch/x86/include/asm/topology.h @@ -31,9 +31,9 @@ * CONFIG_NUMA. */ #include +#include #ifdef CONFIG_NUMA -#include #include #include @@ -139,9 +139,20 @@ static inline int topology_max_smt_threads(void) int topology_update_package_map(unsigned int apicid, unsigned int cpu); int topology_update_die_map(unsigned int dieid, unsigned int cpu); int topology_phys_to_logical_pkg(unsigned int pkg); -bool topology_is_primary_thread(unsigned int cpu); bool topology_smt_supported(void); -#else + +extern struct cpumask __cpu_primary_thread_mask; +#define cpu_primary_thread_mask ((const struct cpumask *)&__cpu_primary_thread_mask) + +/** + * topology_is_primary_thread - Check whether CPU is the primary SMT thread + * @cpu: CPU to check + */ +static inline bool topology_is_primary_thread(unsigned int cpu) +{ + return cpumask_test_cpu(cpu, cpu_primary_thread_mask); +} +#else /* CONFIG_SMP */ #define topology_max_packages() (1) static inline int topology_update_package_map(unsigned int apicid, unsigned int cpu) { return 0; } @@ -152,7 +163,7 @@ static inline int topology_max_die_per_package(void) { return 1; } static inline int topology_max_smt_threads(void) { return 1; } static inline bool topology_is_primary_thread(unsigned int cpu) { return true; } static inline bool topology_smt_supported(void) { return false; } -#endif +#endif /* !CONFIG_SMP */ static inline void arch_fix_phys_package_id(int num, u32 slot) { diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c index 7705571100518..e17600d3e2850 100644 --- a/arch/x86/kernel/apic/apic.c +++ b/arch/x86/kernel/apic/apic.c @@ -2386,20 +2386,16 @@ bool arch_match_cpu_phys_id(int cpu, u64 phys_id) } #ifdef CONFIG_SMP -/** - * apic_id_is_primary_thread - Check whether APIC ID belongs to a primary thread - * @apicid: APIC ID to check - */ -bool apic_id_is_primary_thread(unsigned int apicid) +static void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid) { - u32 mask; - - if (smp_num_siblings == 1) - return true; /* Isolate the SMT bit(s) in the APICID and check for 0 */ - mask = (1U << (fls(smp_num_siblings) - 1)) - 1; - return !(apicid & mask); + u32 mask = (1U << (fls(smp_num_siblings) - 1)) - 1; + + if (smp_num_siblings == 1 || !(apicid & mask)) + cpumask_set_cpu(cpu, &__cpu_primary_thread_mask); } +#else +static inline void cpu_mark_primary_thread(unsigned int cpu, unsigned int apicid) { } #endif /* @@ -2544,6 +2540,8 @@ int generic_processor_info(int apicid, int version) set_cpu_present(cpu, true); num_processors++; + cpu_mark_primary_thread(cpu, apicid); + return cpu; } diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index a27941ac528c7..51122f0ba3f64 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -102,6 +102,9 @@ EXPORT_PER_CPU_SYMBOL(cpu_die_map); DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); EXPORT_PER_CPU_SYMBOL(cpu_info); +/* CPUs which are the primary SMT threads */ +struct cpumask __cpu_primary_thread_mask __read_mostly; + /* Representing CPUs for which sibling maps can be computed */ static cpumask_var_t cpu_sibling_setup_mask; @@ -276,15 +279,6 @@ static void notrace start_secondary(void *unused) cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); } -/** - * topology_is_primary_thread - Check whether CPU is the primary SMT thread - * @cpu: CPU to check - */ -bool topology_is_primary_thread(unsigned int cpu) -{ - return apic_id_is_primary_thread(per_cpu(x86_cpu_to_apicid, cpu)); -} - /** * topology_smt_supported - Check whether SMT is supported by the CPUs */