| /* |
| * x86 SMP booting functions |
| * |
| * (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk> |
| * (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com> |
| * Copyright 2001 Andi Kleen, SuSE Labs. |
| * |
| * Much of the core SMP work is based on previous work by Thomas Radke, to |
| * whom a great many thanks are extended. |
| * |
| * Thanks to Intel for making available several different Pentium, |
| * Pentium Pro and Pentium-II/Xeon MP machines. |
| * Original development of Linux SMP code supported by Caldera. |
| * |
| * This code is released under the GNU General Public License version 2 or |
| * later. |
| * |
| * Fixes |
| * Felix Koop : NR_CPUS used properly |
| * Jose Renau : Handle single CPU case. |
| * Alan Cox : By repeated request 8) - Total BogoMIPS report. |
| * Greg Wright : Fix for kernel stacks panic. |
| * Erich Boleyn : MP v1.4 and additional changes. |
| * Matthias Sattler : Changes for 2.1 kernel map. |
| * Michel Lespinasse : Changes for 2.1 kernel map. |
| * Michael Chastain : Change trampoline.S to gnu as. |
| * Alan Cox : Dumb bug: 'B' step PPro's are fine |
| * Ingo Molnar : Added APIC timers, based on code |
| * from Jose Renau |
| * Ingo Molnar : various cleanups and rewrites |
| * Tigran Aivazian : fixed "0.00 in /proc/uptime on SMP" bug. |
| * Maciej W. Rozycki : Bits for genuine 82489DX APICs |
| * Andi Kleen : Changed for SMP boot into long mode. |
| * Martin J. Bligh : Added support for multi-quad systems |
| * Dave Jones : Report invalid combinations of Athlon CPUs. |
| * Rusty Russell : Hacked into shape for new "hotplug" boot process. |
| * Andi Kleen : Converted to new state machine. |
| * Ashok Raj : CPU hotplug support |
| * Glauber Costa : i386 and x86_64 integration |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/init.h> |
| #include <linux/smp.h> |
| #include <linux/export.h> |
| #include <linux/sched.h> |
| #include <linux/sched/topology.h> |
| #include <linux/sched/hotplug.h> |
| #include <linux/sched/task_stack.h> |
| #include <linux/percpu.h> |
| #include <linux/memblock.h> |
| #include <linux/err.h> |
| #include <linux/nmi.h> |
| #include <linux/tboot.h> |
| #include <linux/stackprotector.h> |
| #include <linux/gfp.h> |
| #include <linux/cpuidle.h> |
| #include <linux/numa.h> |
| |
| #include <asm/acpi.h> |
| #include <asm/desc.h> |
| #include <asm/nmi.h> |
| #include <asm/irq.h> |
| #include <asm/realmode.h> |
| #include <asm/cpu.h> |
| #include <asm/numa.h> |
| #include <asm/pgtable.h> |
| #include <asm/tlbflush.h> |
| #include <asm/mtrr.h> |
| #include <asm/mwait.h> |
| #include <asm/apic.h> |
| #include <asm/io_apic.h> |
| #include <asm/fpu/internal.h> |
| #include <asm/setup.h> |
| #include <asm/uv/uv.h> |
| #include <linux/mc146818rtc.h> |
| #include <asm/i8259.h> |
| #include <asm/misc.h> |
| #include <asm/qspinlock.h> |
| #include <asm/intel-family.h> |
| #include <asm/cpu_device_id.h> |
| #include <asm/spec-ctrl.h> |
| #include <asm/hw_irq.h> |
| |
| /* representing HT siblings of each logical CPU */ |
| DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_sibling_map); |
| EXPORT_PER_CPU_SYMBOL(cpu_sibling_map); |
| |
| /* representing HT and core siblings of each logical CPU */ |
| DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_core_map); |
| EXPORT_PER_CPU_SYMBOL(cpu_core_map); |
| |
| DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); |
| |
| /* Per CPU bogomips and other parameters */ |
| DEFINE_PER_CPU_READ_MOSTLY(struct cpuinfo_x86, cpu_info); |
| EXPORT_PER_CPU_SYMBOL(cpu_info); |
| |
| /* Logical package management. We might want to allocate that dynamically */ |
| unsigned int __max_logical_packages __read_mostly; |
| EXPORT_SYMBOL(__max_logical_packages); |
| static unsigned int logical_packages __read_mostly; |
| |
| /* Maximum number of SMT threads on any online core */ |
| int __read_mostly __max_smt_threads = 1; |
| |
| /* Flag to indicate if a complete sched domain rebuild is required */ |
| bool x86_topology_update; |
| |
| int arch_update_cpu_topology(void) |
| { |
| int retval = x86_topology_update; |
| |
| x86_topology_update = false; |
| return retval; |
| } |
| |
| static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&rtc_lock, flags); |
| CMOS_WRITE(0xa, 0xf); |
| spin_unlock_irqrestore(&rtc_lock, flags); |
| *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_HIGH)) = |
| start_eip >> 4; |
| *((volatile unsigned short *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = |
| start_eip & 0xf; |
| } |
| |
| static inline void smpboot_restore_warm_reset_vector(void) |
| { |
| unsigned long flags; |
| |
| /* |
| * Paranoid: Set warm reset code and vector here back |
| * to default values. |
| */ |
| spin_lock_irqsave(&rtc_lock, flags); |
| CMOS_WRITE(0, 0xf); |
| spin_unlock_irqrestore(&rtc_lock, flags); |
| |
| *((volatile u32 *)phys_to_virt(TRAMPOLINE_PHYS_LOW)) = 0; |
| } |
| |
| /* |
| * Report back to the Boot Processor during boot time or to the caller processor |
| * during CPU online. |
| */ |
| static void smp_callin(void) |
| { |
| int cpuid; |
| |
| /* |
| * If waken up by an INIT in an 82489DX configuration |
| * cpu_callout_mask guarantees we don't get here before |
| * an INIT_deassert IPI reaches our local APIC, so it is |
| * now safe to touch our local APIC. |
| */ |
| cpuid = smp_processor_id(); |
| |
| /* |
| * the boot CPU has finished the init stage and is spinning |
| * on callin_map until we finish. We are free to set up this |
| * CPU, first the APIC. (this is probably redundant on most |
| * boards) |
| */ |
| apic_ap_setup(); |
| |
| /* |
| * Save our processor parameters. Note: this information |
| * is needed for clock calibration. |
| */ |
| smp_store_cpu_info(cpuid); |
| |
| /* |
| * The topology information must be up to date before |
| * calibrate_delay() and notify_cpu_starting(). |
| */ |
| set_cpu_sibling_map(raw_smp_processor_id()); |
| |
| /* |
| * Get our bogomips. |
| * Update loops_per_jiffy in cpu_data. Previous call to |
| * smp_store_cpu_info() stored a value that is close but not as |
| * accurate as the value just calculated. |
| */ |
| calibrate_delay(); |
| cpu_data(cpuid).loops_per_jiffy = loops_per_jiffy; |
| pr_debug("Stack at about %p\n", &cpuid); |
| |
| wmb(); |
| |
| notify_cpu_starting(cpuid); |
| |
| /* |
| * Allow the master to continue. |
| */ |
| cpumask_set_cpu(cpuid, cpu_callin_mask); |
| } |
| |
| static int cpu0_logical_apicid; |
| static int enable_start_cpu0; |
| /* |
| * Activate a secondary processor. |
| */ |
| static void notrace start_secondary(void *unused) |
| { |
| /* |
| * Don't put *anything* except direct CPU state initialization |
| * before cpu_init(), SMP booting is too fragile that we want to |
| * limit the things done here to the most necessary things. |
| */ |
| if (boot_cpu_has(X86_FEATURE_PCID)) |
| __write_cr4(__read_cr4() | X86_CR4_PCIDE); |
| |
| #ifdef CONFIG_X86_32 |
| /* switch away from the initial page table */ |
| load_cr3(swapper_pg_dir); |
| /* |
| * Initialize the CR4 shadow before doing anything that could |
| * try to read it. |
| */ |
| cr4_init_shadow(); |
| __flush_tlb_all(); |
| #endif |
| load_current_idt(); |
| cpu_init(); |
| x86_cpuinit.early_percpu_clock_init(); |
| preempt_disable(); |
| smp_callin(); |
| |
| enable_start_cpu0 = 0; |
| |
| /* otherwise gcc will move up smp_processor_id before the cpu_init */ |
| barrier(); |
| /* |
| * Check TSC synchronization with the boot CPU: |
| */ |
| check_tsc_sync_target(); |
| |
| speculative_store_bypass_ht_init(); |
| |
| /* |
| * Lock vector_lock, set CPU online and bring the vector |
| * allocator online. Online must be set with vector_lock held |
| * to prevent a concurrent irq setup/teardown from seeing a |
| * half valid vector space. |
| */ |
| lock_vector_lock(); |
| set_cpu_online(smp_processor_id(), true); |
| lapic_online(); |
| unlock_vector_lock(); |
| cpu_set_state_online(smp_processor_id()); |
| x86_platform.nmi_init(); |
| |
| /* enable local interrupts */ |
| local_irq_enable(); |
| |
| /* to prevent fake stack check failure in clock setup */ |
| boot_init_stack_canary(); |
| |
| x86_cpuinit.setup_percpu_clockev(); |
| |
| wmb(); |
| 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 |
| */ |
| bool topology_smt_supported(void) |
| { |
| return smp_num_siblings > 1; |
| } |
| |
| /** |
| * topology_phys_to_logical_pkg - Map a physical package id to a logical |
| * |
| * Returns logical package id or -1 if not found |
| */ |
| int topology_phys_to_logical_pkg(unsigned int phys_pkg) |
| { |
| int cpu; |
| |
| for_each_possible_cpu(cpu) { |
| struct cpuinfo_x86 *c = &cpu_data(cpu); |
| |
| if (c->initialized && c->phys_proc_id == phys_pkg) |
| return c->logical_proc_id; |
| } |
| return -1; |
| } |
| EXPORT_SYMBOL(topology_phys_to_logical_pkg); |
| |
| /** |
| * topology_update_package_map - Update the physical to logical package map |
| * @pkg: The physical package id as retrieved via CPUID |
| * @cpu: The cpu for which this is updated |
| */ |
| int topology_update_package_map(unsigned int pkg, unsigned int cpu) |
| { |
| int new; |
| |
| /* Already available somewhere? */ |
| new = topology_phys_to_logical_pkg(pkg); |
| if (new >= 0) |
| goto found; |
| |
| new = logical_packages++; |
| if (new != pkg) { |
| pr_info("CPU %u Converting physical %u to logical package %u\n", |
| cpu, pkg, new); |
| } |
| found: |
| cpu_data(cpu).logical_proc_id = new; |
| return 0; |
| } |
| |
| void __init smp_store_boot_cpu_info(void) |
| { |
| int id = 0; /* CPU 0 */ |
| struct cpuinfo_x86 *c = &cpu_data(id); |
| |
| *c = boot_cpu_data; |
| c->cpu_index = id; |
| topology_update_package_map(c->phys_proc_id, id); |
| c->initialized = true; |
| } |
| |
| /* |
| * The bootstrap kernel entry code has set these up. Save them for |
| * a given CPU |
| */ |
| void smp_store_cpu_info(int id) |
| { |
| struct cpuinfo_x86 *c = &cpu_data(id); |
| |
| /* Copy boot_cpu_data only on the first bringup */ |
| if (!c->initialized) |
| *c = boot_cpu_data; |
| c->cpu_index = id; |
| /* |
| * During boot time, CPU0 has this setup already. Save the info when |
| * bringing up AP or offlined CPU0. |
| */ |
| identify_secondary_cpu(c); |
| c->initialized = true; |
| } |
| |
| static bool |
| topology_same_node(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) |
| { |
| int cpu1 = c->cpu_index, cpu2 = o->cpu_index; |
| |
| return (cpu_to_node(cpu1) == cpu_to_node(cpu2)); |
| } |
| |
| static bool |
| topology_sane(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o, const char *name) |
| { |
| int cpu1 = c->cpu_index, cpu2 = o->cpu_index; |
| |
| return !WARN_ONCE(!topology_same_node(c, o), |
| "sched: CPU #%d's %s-sibling CPU #%d is not on the same node! " |
| "[node: %d != %d]. Ignoring dependency.\n", |
| cpu1, name, cpu2, cpu_to_node(cpu1), cpu_to_node(cpu2)); |
| } |
| |
| #define link_mask(mfunc, c1, c2) \ |
| do { \ |
| cpumask_set_cpu((c1), mfunc(c2)); \ |
| cpumask_set_cpu((c2), mfunc(c1)); \ |
| } while (0) |
| |
| static bool match_smt(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) |
| { |
| if (boot_cpu_has(X86_FEATURE_TOPOEXT)) { |
| int cpu1 = c->cpu_index, cpu2 = o->cpu_index; |
| |
| if (c->phys_proc_id == o->phys_proc_id && |
| per_cpu(cpu_llc_id, cpu1) == per_cpu(cpu_llc_id, cpu2)) { |
| if (c->cpu_core_id == o->cpu_core_id) |
| return topology_sane(c, o, "smt"); |
| |
| if ((c->cu_id != 0xff) && |
| (o->cu_id != 0xff) && |
| (c->cu_id == o->cu_id)) |
| return topology_sane(c, o, "smt"); |
| } |
| |
| } else if (c->phys_proc_id == o->phys_proc_id && |
| c->cpu_core_id == o->cpu_core_id) { |
| return topology_sane(c, o, "smt"); |
| } |
| |
| return false; |
| } |
| |
| /* |
| * Define snc_cpu[] for SNC (Sub-NUMA Cluster) CPUs. |
| * |
| * These are Intel CPUs that enumerate an LLC that is shared by |
| * multiple NUMA nodes. The LLC on these systems is shared for |
| * off-package data access but private to the NUMA node (half |
| * of the package) for on-package access. |
| * |
| * CPUID (the source of the information about the LLC) can only |
| * enumerate the cache as being shared *or* unshared, but not |
| * this particular configuration. The CPU in this case enumerates |
| * the cache to be shared across the entire package (spanning both |
| * NUMA nodes). |
| */ |
| |
| static const struct x86_cpu_id snc_cpu[] = { |
| { X86_VENDOR_INTEL, 6, INTEL_FAM6_SKYLAKE_X }, |
| {} |
| }; |
| |
| static bool match_llc(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) |
| { |
| int cpu1 = c->cpu_index, cpu2 = o->cpu_index; |
| |
| /* Do not match if we do not have a valid APICID for cpu: */ |
| if (per_cpu(cpu_llc_id, cpu1) == BAD_APICID) |
| return false; |
| |
| /* Do not match if LLC id does not match: */ |
| if (per_cpu(cpu_llc_id, cpu1) != per_cpu(cpu_llc_id, cpu2)) |
| return false; |
| |
| /* |
| * Allow the SNC topology without warning. Return of false |
| * means 'c' does not share the LLC of 'o'. This will be |
| * reflected to userspace. |
| */ |
| if (!topology_same_node(c, o) && x86_match_cpu(snc_cpu)) |
| return false; |
| |
| return topology_sane(c, o, "llc"); |
| } |
| |
| /* |
| * Unlike the other levels, we do not enforce keeping a |
| * multicore group inside a NUMA node. If this happens, we will |
| * discard the MC level of the topology later. |
| */ |
| static bool match_die(struct cpuinfo_x86 *c, struct cpuinfo_x86 *o) |
| { |
| if (c->phys_proc_id == o->phys_proc_id) |
| return true; |
| return false; |
| } |
| |
| #if defined(CONFIG_SCHED_SMT) || defined(CONFIG_SCHED_MC) |
| static inline int x86_sched_itmt_flags(void) |
| { |
| return sysctl_sched_itmt_enabled ? SD_ASYM_PACKING : 0; |
| } |
| |
| #ifdef CONFIG_SCHED_MC |
| static int x86_core_flags(void) |
| { |
| return cpu_core_flags() | x86_sched_itmt_flags(); |
| } |
| #endif |
| #ifdef CONFIG_SCHED_SMT |
| static int x86_smt_flags(void) |
| { |
| return cpu_smt_flags() | x86_sched_itmt_flags(); |
| } |
| #endif |
| #endif |
| |
| static struct sched_domain_topology_level x86_numa_in_package_topology[] = { |
| #ifdef CONFIG_SCHED_SMT |
| { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) }, |
| #endif |
| #ifdef CONFIG_SCHED_MC |
| { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) }, |
| #endif |
| { NULL, }, |
| }; |
| |
| static struct sched_domain_topology_level x86_topology[] = { |
| #ifdef CONFIG_SCHED_SMT |
| { cpu_smt_mask, x86_smt_flags, SD_INIT_NAME(SMT) }, |
| #endif |
| #ifdef CONFIG_SCHED_MC |
| { cpu_coregroup_mask, x86_core_flags, SD_INIT_NAME(MC) }, |
| #endif |
| { cpu_cpu_mask, SD_INIT_NAME(DIE) }, |
| { NULL, }, |
| }; |
| |
| /* |
| * Set if a package/die has multiple NUMA nodes inside. |
| * AMD Magny-Cours, Intel Cluster-on-Die, and Intel |
| * Sub-NUMA Clustering have this. |
| */ |
| static bool x86_has_numa_in_package; |
| |
| void set_cpu_sibling_map(int cpu) |
| { |
| bool has_smt = smp_num_siblings > 1; |
| bool has_mp = has_smt || boot_cpu_data.x86_max_cores > 1; |
| struct cpuinfo_x86 *c = &cpu_data(cpu); |
| struct cpuinfo_x86 *o; |
| int i, threads; |
| |
| cpumask_set_cpu(cpu, cpu_sibling_setup_mask); |
| |
| if (!has_mp) { |
| cpumask_set_cpu(cpu, topology_sibling_cpumask(cpu)); |
| cpumask_set_cpu(cpu, cpu_llc_shared_mask(cpu)); |
| cpumask_set_cpu(cpu, topology_core_cpumask(cpu)); |
| c->booted_cores = 1; |
| return; |
| } |
| |
| for_each_cpu(i, cpu_sibling_setup_mask) { |
| o = &cpu_data(i); |
| |
| if ((i == cpu) || (has_smt && match_smt(c, o))) |
| link_mask(topology_sibling_cpumask, cpu, i); |
| |
| if ((i == cpu) || (has_mp && match_llc(c, o))) |
| link_mask(cpu_llc_shared_mask, cpu, i); |
| |
| } |
| |
| /* |
| * This needs a separate iteration over the cpus because we rely on all |
| * topology_sibling_cpumask links to be set-up. |
| */ |
| for_each_cpu(i, cpu_sibling_setup_mask) { |
| o = &cpu_data(i); |
| |
| if ((i == cpu) || (has_mp && match_die(c, o))) { |
| link_mask(topology_core_cpumask, cpu, i); |
| |
| /* |
| * Does this new cpu bringup a new core? |
| */ |
| if (cpumask_weight( |
| topology_sibling_cpumask(cpu)) == 1) { |
| /* |
| * for each core in package, increment |
| * the booted_cores for this new cpu |
| */ |
| if (cpumask_first( |
| topology_sibling_cpumask(i)) == i) |
| c->booted_cores++; |
| /* |
| * increment the core count for all |
| * the other cpus in this package |
| */ |
| if (i != cpu) |
| cpu_data(i).booted_cores++; |
| } else if (i != cpu && !c->booted_cores) |
| c->booted_cores = cpu_data(i).booted_cores; |
| } |
| if (match_die(c, o) && !topology_same_node(c, o)) |
| x86_has_numa_in_package = true; |
| } |
| |
| threads = cpumask_weight(topology_sibling_cpumask(cpu)); |
| if (threads > __max_smt_threads) |
| __max_smt_threads = threads; |
| } |
| |
| /* maps the cpu to the sched domain representing multi-core */ |
| const struct cpumask *cpu_coregroup_mask(int cpu) |
| { |
| return cpu_llc_shared_mask(cpu); |
| } |
| |
| static void impress_friends(void) |
| { |
| int cpu; |
| unsigned long bogosum = 0; |
| /* |
| * Allow the user to impress friends. |
| */ |
| pr_debug("Before bogomips\n"); |
| for_each_possible_cpu(cpu) |
| if (cpumask_test_cpu(cpu, cpu_callout_mask)) |
| bogosum += cpu_data(cpu).loops_per_jiffy; |
| pr_info("Total of %d processors activated (%lu.%02lu BogoMIPS)\n", |
| num_online_cpus(), |
| bogosum/(500000/HZ), |
| (bogosum/(5000/HZ))%100); |
| |
| pr_debug("Before bogocount - setting activated=1\n"); |
| } |
| |
| void __inquire_remote_apic(int apicid) |
| { |
| unsigned i, regs[] = { APIC_ID >> 4, APIC_LVR >> 4, APIC_SPIV >> 4 }; |
| const char * const names[] = { "ID", "VERSION", "SPIV" }; |
| int timeout; |
| u32 status; |
| |
| pr_info("Inquiring remote APIC 0x%x...\n", apicid); |
| |
| for (i = 0; i < ARRAY_SIZE(regs); i++) { |
| pr_info("... APIC 0x%x %s: ", apicid, names[i]); |
| |
| /* |
| * Wait for idle. |
| */ |
| status = safe_apic_wait_icr_idle(); |
| if (status) |
| pr_cont("a previous APIC delivery may have failed\n"); |
| |
| apic_icr_write(APIC_DM_REMRD | regs[i], apicid); |
| |
| timeout = 0; |
| do { |
| udelay(100); |
| status = apic_read(APIC_ICR) & APIC_ICR_RR_MASK; |
| } while (status == APIC_ICR_RR_INPROG && timeout++ < 1000); |
| |
| switch (status) { |
| case APIC_ICR_RR_VALID: |
| status = apic_read(APIC_RRR); |
| pr_cont("%08x\n", status); |
| break; |
| default: |
| pr_cont("failed\n"); |
| } |
| } |
| } |
| |
| /* |
| * The Multiprocessor Specification 1.4 (1997) example code suggests |
| * that there should be a 10ms delay between the BSP asserting INIT |
| * and de-asserting INIT, when starting a remote processor. |
| * But that slows boot and resume on modern processors, which include |
| * many cores and don't require that delay. |
| * |
| * Cmdline "init_cpu_udelay=" is available to over-ride this delay. |
| * Modern processor families are quirked to remove the delay entirely. |
| */ |
| #define UDELAY_10MS_DEFAULT 10000 |
| |
| static unsigned int init_udelay = UINT_MAX; |
| |
| static int __init cpu_init_udelay(char *str) |
| { |
| get_option(&str, &init_udelay); |
| |
| return 0; |
| } |
| early_param("cpu_init_udelay", cpu_init_udelay); |
| |
| static void __init smp_quirk_init_udelay(void) |
| { |
| /* if cmdline changed it from default, leave it alone */ |
| if (init_udelay != UINT_MAX) |
| return; |
| |
| /* if modern processor, use no delay */ |
| if (((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 6)) || |
| ((boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) && (boot_cpu_data.x86 >= 0x18)) || |
| ((boot_cpu_data.x86_vendor == X86_VENDOR_AMD) && (boot_cpu_data.x86 >= 0xF))) { |
| init_udelay = 0; |
| return; |
| } |
| /* else, use legacy delay */ |
| init_udelay = UDELAY_10MS_DEFAULT; |
| } |
| |
| /* |
| * Poke the other CPU in the eye via NMI to wake it up. Remember that the normal |
| * INIT, INIT, STARTUP sequence will reset the chip hard for us, and this |
| * won't ... remember to clear down the APIC, etc later. |
| */ |
| int |
| wakeup_secondary_cpu_via_nmi(int apicid, unsigned long start_eip) |
| { |
| unsigned long send_status, accept_status = 0; |
| int maxlvt; |
| |
| /* Target chip */ |
| /* Boot on the stack */ |
| /* Kick the second */ |
| apic_icr_write(APIC_DM_NMI | apic->dest_logical, apicid); |
| |
| pr_debug("Waiting for send to finish...\n"); |
| send_status = safe_apic_wait_icr_idle(); |
| |
| /* |
| * Give the other CPU some time to accept the IPI. |
| */ |
| udelay(200); |
| if (APIC_INTEGRATED(boot_cpu_apic_version)) { |
| maxlvt = lapic_get_maxlvt(); |
| if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ |
| apic_write(APIC_ESR, 0); |
| accept_status = (apic_read(APIC_ESR) & 0xEF); |
| } |
| pr_debug("NMI sent\n"); |
| |
| if (send_status) |
| pr_err("APIC never delivered???\n"); |
| if (accept_status) |
| pr_err("APIC delivery error (%lx)\n", accept_status); |
| |
| return (send_status | accept_status); |
| } |
| |
| static int |
| wakeup_secondary_cpu_via_init(int phys_apicid, unsigned long start_eip) |
| { |
| unsigned long send_status = 0, accept_status = 0; |
| int maxlvt, num_starts, j; |
| |
| maxlvt = lapic_get_maxlvt(); |
| |
| /* |
| * Be paranoid about clearing APIC errors. |
| */ |
| if (APIC_INTEGRATED(boot_cpu_apic_version)) { |
| if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ |
| apic_write(APIC_ESR, 0); |
| apic_read(APIC_ESR); |
| } |
| |
| pr_debug("Asserting INIT\n"); |
| |
| /* |
| * Turn INIT on target chip |
| */ |
| /* |
| * Send IPI |
| */ |
| apic_icr_write(APIC_INT_LEVELTRIG | APIC_INT_ASSERT | APIC_DM_INIT, |
| phys_apicid); |
| |
| pr_debug("Waiting for send to finish...\n"); |
| send_status = safe_apic_wait_icr_idle(); |
| |
| udelay(init_udelay); |
| |
| pr_debug("Deasserting INIT\n"); |
| |
| /* Target chip */ |
| /* Send IPI */ |
| apic_icr_write(APIC_INT_LEVELTRIG | APIC_DM_INIT, phys_apicid); |
| |
| pr_debug("Waiting for send to finish...\n"); |
| send_status = safe_apic_wait_icr_idle(); |
| |
| mb(); |
| |
| /* |
| * Should we send STARTUP IPIs ? |
| * |
| * Determine this based on the APIC version. |
| * If we don't have an integrated APIC, don't send the STARTUP IPIs. |
| */ |
| if (APIC_INTEGRATED(boot_cpu_apic_version)) |
| num_starts = 2; |
| else |
| num_starts = 0; |
| |
| /* |
| * Run STARTUP IPI loop. |
| */ |
| pr_debug("#startup loops: %d\n", num_starts); |
| |
| for (j = 1; j <= num_starts; j++) { |
| pr_debug("Sending STARTUP #%d\n", j); |
| if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ |
| apic_write(APIC_ESR, 0); |
| apic_read(APIC_ESR); |
| pr_debug("After apic_write\n"); |
| |
| /* |
| * STARTUP IPI |
| */ |
| |
| /* Target chip */ |
| /* Boot on the stack */ |
| /* Kick the second */ |
| apic_icr_write(APIC_DM_STARTUP | (start_eip >> 12), |
| phys_apicid); |
| |
| /* |
| * Give the other CPU some time to accept the IPI. |
| */ |
| if (init_udelay == 0) |
| udelay(10); |
| else |
| udelay(300); |
| |
| pr_debug("Startup point 1\n"); |
| |
| pr_debug("Waiting for send to finish...\n"); |
| send_status = safe_apic_wait_icr_idle(); |
| |
| /* |
| * Give the other CPU some time to accept the IPI. |
| */ |
| if (init_udelay == 0) |
| udelay(10); |
| else |
| udelay(200); |
| |
| if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */ |
| apic_write(APIC_ESR, 0); |
| accept_status = (apic_read(APIC_ESR) & 0xEF); |
| if (send_status || accept_status) |
| break; |
| } |
| pr_debug("After Startup\n"); |
| |
| if (send_status) |
| pr_err("APIC never delivered???\n"); |
| if (accept_status) |
| pr_err("APIC delivery error (%lx)\n", accept_status); |
| |
| return (send_status | accept_status); |
| } |
| |
| /* reduce the number of lines printed when booting a large cpu count system */ |
| static void announce_cpu(int cpu, int apicid) |
| { |
| static int current_node = NUMA_NO_NODE; |
| int node = early_cpu_to_node(cpu); |
| static int width, node_width; |
| |
| if (!width) |
| width = num_digits(num_possible_cpus()) + 1; /* + '#' sign */ |
| |
| if (!node_width) |
| node_width = num_digits(num_possible_nodes()) + 1; /* + '#' */ |
| |
| if (cpu == 1) |
| printk(KERN_INFO "x86: Booting SMP configuration:\n"); |
| |
| if (system_state < SYSTEM_RUNNING) { |
| if (node != current_node) { |
| if (current_node > (-1)) |
| pr_cont("\n"); |
| current_node = node; |
| |
| printk(KERN_INFO ".... node %*s#%d, CPUs: ", |
| node_width - num_digits(node), " ", node); |
| } |
| |
| /* Add padding for the BSP */ |
| if (cpu == 1) |
| pr_cont("%*s", width + 1, " "); |
| |
| pr_cont("%*s#%d", width - num_digits(cpu), " ", cpu); |
| |
| } else |
| pr_info("Booting Node %d Processor %d APIC 0x%x\n", |
| node, cpu, apicid); |
| } |
| |
| static int wakeup_cpu0_nmi(unsigned int cmd, struct pt_regs *regs) |
| { |
| int cpu; |
| |
| cpu = smp_processor_id(); |
| if (cpu == 0 && !cpu_online(cpu) && enable_start_cpu0) |
| return NMI_HANDLED; |
| |
| return NMI_DONE; |
| } |
| |
| /* |
| * Wake up AP by INIT, INIT, STARTUP sequence. |
| * |
| * Instead of waiting for STARTUP after INITs, BSP will execute the BIOS |
| * boot-strap code which is not a desired behavior for waking up BSP. To |
| * void the boot-strap code, wake up CPU0 by NMI instead. |
| * |
| * This works to wake up soft offlined CPU0 only. If CPU0 is hard offlined |
| * (i.e. physically hot removed and then hot added), NMI won't wake it up. |
| * We'll change this code in the future to wake up hard offlined CPU0 if |
| * real platform and request are available. |
| */ |
| static int |
| wakeup_cpu_via_init_nmi(int cpu, unsigned long start_ip, int apicid, |
| int *cpu0_nmi_registered) |
| { |
| int id; |
| int boot_error; |
| |
| preempt_disable(); |
| |
| /* |
| * Wake up AP by INIT, INIT, STARTUP sequence. |
| */ |
| if (cpu) { |
| boot_error = wakeup_secondary_cpu_via_init(apicid, start_ip); |
| goto out; |
| } |
| |
| /* |
| * Wake up BSP by nmi. |
| * |
| * Register a NMI handler to help wake up CPU0. |
| */ |
| boot_error = register_nmi_handler(NMI_LOCAL, |
| wakeup_cpu0_nmi, 0, "wake_cpu0"); |
| |
| if (!boot_error) { |
| enable_start_cpu0 = 1; |
| *cpu0_nmi_registered = 1; |
| if (apic->dest_logical == APIC_DEST_LOGICAL) |
| id = cpu0_logical_apicid; |
| else |
| id = apicid; |
| boot_error = wakeup_secondary_cpu_via_nmi(id, start_ip); |
| } |
| |
| out: |
| preempt_enable(); |
| |
| return boot_error; |
| } |
| |
| void common_cpu_up(unsigned int cpu, struct task_struct *idle) |
| { |
| /* Just in case we booted with a single CPU. */ |
| alternatives_enable_smp(); |
| |
| per_cpu(current_task, cpu) = idle; |
| |
| #ifdef CONFIG_X86_32 |
| /* Stack for startup_32 can be just as for start_secondary onwards */ |
| irq_ctx_init(cpu); |
| per_cpu(cpu_current_top_of_stack, cpu) = task_top_of_stack(idle); |
| #else |
| initial_gs = per_cpu_offset(cpu); |
| #endif |
| } |
| |
| /* |
| * NOTE - on most systems this is a PHYSICAL apic ID, but on multiquad |
| * (ie clustered apic addressing mode), this is a LOGICAL apic ID. |
| * Returns zero if CPU booted OK, else error code from |
| * ->wakeup_secondary_cpu. |
| */ |
| static int do_boot_cpu(int apicid, int cpu, struct task_struct *idle, |
| int *cpu0_nmi_registered) |
| { |
| volatile u32 *trampoline_status = |
| (volatile u32 *) __va(real_mode_header->trampoline_status); |
| /* start_ip had better be page-aligned! */ |
| unsigned long start_ip = real_mode_header->trampoline_start; |
| |
| unsigned long boot_error = 0; |
| unsigned long timeout; |
| |
| idle->thread.sp = (unsigned long)task_pt_regs(idle); |
| early_gdt_descr.address = (unsigned long)get_cpu_gdt_rw(cpu); |
| initial_code = (unsigned long)start_secondary; |
| initial_stack = idle->thread.sp; |
| |
| /* Enable the espfix hack for this CPU */ |
| init_espfix_ap(cpu); |
| |
| /* So we see what's up */ |
| announce_cpu(cpu, apicid); |
| |
| /* |
| * This grunge runs the startup process for |
| * the targeted processor. |
| */ |
| |
| if (x86_platform.legacy.warm_reset) { |
| |
| pr_debug("Setting warm reset code and vector.\n"); |
| |
| smpboot_setup_warm_reset_vector(start_ip); |
| /* |
| * Be paranoid about clearing APIC errors. |
| */ |
| if (APIC_INTEGRATED(boot_cpu_apic_version)) { |
| apic_write(APIC_ESR, 0); |
| apic_read(APIC_ESR); |
| } |
| } |
| |
| /* |
| * AP might wait on cpu_callout_mask in cpu_init() with |
| * cpu_initialized_mask set if previous attempt to online |
| * it timed-out. Clear cpu_initialized_mask so that after |
| * INIT/SIPI it could start with a clean state. |
| */ |
| cpumask_clear_cpu(cpu, cpu_initialized_mask); |
| smp_mb(); |
| |
| /* |
| * Wake up a CPU in difference cases: |
| * - Use the method in the APIC driver if it's defined |
| * Otherwise, |
| * - Use an INIT boot APIC message for APs or NMI for BSP. |
| */ |
| if (apic->wakeup_secondary_cpu) |
| boot_error = apic->wakeup_secondary_cpu(apicid, start_ip); |
| else |
| boot_error = wakeup_cpu_via_init_nmi(cpu, start_ip, apicid, |
| cpu0_nmi_registered); |
| |
| if (!boot_error) { |
| /* |
| * Wait 10s total for first sign of life from AP |
| */ |
| boot_error = -1; |
| timeout = jiffies + 10*HZ; |
| while (time_before(jiffies, timeout)) { |
| if (cpumask_test_cpu(cpu, cpu_initialized_mask)) { |
| /* |
| * Tell AP to proceed with initialization |
| */ |
| cpumask_set_cpu(cpu, cpu_callout_mask); |
| boot_error = 0; |
| break; |
| } |
| schedule(); |
| } |
| } |
| |
| if (!boot_error) { |
| /* |
| * Wait till AP completes initial initialization |
| */ |
| while (!cpumask_test_cpu(cpu, cpu_callin_mask)) { |
| /* |
| * Allow other tasks to run while we wait for the |
| * AP to come online. This also gives a chance |
| * for the MTRR work(triggered by the AP coming online) |
| * to be completed in the stop machine context. |
| */ |
| schedule(); |
| } |
| } |
| |
| /* mark "stuck" area as not stuck */ |
| *trampoline_status = 0; |
| |
| if (x86_platform.legacy.warm_reset) { |
| /* |
| * Cleanup possible dangling ends... |
| */ |
| smpboot_restore_warm_reset_vector(); |
| } |
| |
| return boot_error; |
| } |
| |
| int native_cpu_up(unsigned int cpu, struct task_struct *tidle) |
| { |
| int apicid = apic->cpu_present_to_apicid(cpu); |
| int cpu0_nmi_registered = 0; |
| unsigned long flags; |
| int err, ret = 0; |
| |
| lockdep_assert_irqs_enabled(); |
| |
| pr_debug("++++++++++++++++++++=_---CPU UP %u\n", cpu); |
| |
| if (apicid == BAD_APICID || |
| !physid_isset(apicid, phys_cpu_present_map) || |
| !apic->apic_id_valid(apicid)) { |
| pr_err("%s: bad cpu %d\n", __func__, cpu); |
| return -EINVAL; |
| } |
| |
| /* |
| * Already booted CPU? |
| */ |
| if (cpumask_test_cpu(cpu, cpu_callin_mask)) { |
| pr_debug("do_boot_cpu %d Already started\n", cpu); |
| return -ENOSYS; |
| } |
| |
| /* |
| * Save current MTRR state in case it was changed since early boot |
| * (e.g. by the ACPI SMI) to initialize new CPUs with MTRRs in sync: |
| */ |
| mtrr_save_state(); |
| |
| /* x86 CPUs take themselves offline, so delayed offline is OK. */ |
| err = cpu_check_up_prepare(cpu); |
| if (err && err != -EBUSY) |
| return err; |
| |
| /* the FPU context is blank, nobody can own it */ |
| per_cpu(fpu_fpregs_owner_ctx, cpu) = NULL; |
| |
| common_cpu_up(cpu, tidle); |
| |
| err = do_boot_cpu(apicid, cpu, tidle, &cpu0_nmi_registered); |
| if (err) { |
| pr_err("do_boot_cpu failed(%d) to wakeup CPU#%u\n", err, cpu); |
| ret = -EIO; |
| goto unreg_nmi; |
| } |
| |
| /* |
| * Check TSC synchronization with the AP (keep irqs disabled |
| * while doing so): |
| */ |
| local_irq_save(flags); |
| check_tsc_sync_source(cpu); |
| local_irq_restore(flags); |
| |
| while (!cpu_online(cpu)) { |
| cpu_relax(); |
| touch_nmi_watchdog(); |
| } |
| |
| unreg_nmi: |
| /* |
| * Clean up the nmi handler. Do this after the callin and callout sync |
| * to avoid impact of possible long unregister time. |
| */ |
| if (cpu0_nmi_registered) |
| unregister_nmi_handler(NMI_LOCAL, "wake_cpu0"); |
| |
| return ret; |
| } |
| |
| /** |
| * arch_disable_smp_support() - disables SMP support for x86 at runtime |
| */ |
| void arch_disable_smp_support(void) |
| { |
| disable_ioapic_support(); |
| } |
| |
| /* |
| * Fall back to non SMP mode after errors. |
| * |
| * RED-PEN audit/test this more. I bet there is more state messed up here. |
| */ |
| static __init void disable_smp(void) |
| { |
| pr_info("SMP disabled\n"); |
| |
| disable_ioapic_support(); |
| |
| init_cpu_present(cpumask_of(0)); |
| init_cpu_possible(cpumask_of(0)); |
| |
| if (smp_found_config) |
| physid_set_mask_of_physid(boot_cpu_physical_apicid, &phys_cpu_present_map); |
| else |
| physid_set_mask_of_physid(0, &phys_cpu_present_map); |
| cpumask_set_cpu(0, topology_sibling_cpumask(0)); |
| cpumask_set_cpu(0, topology_core_cpumask(0)); |
| } |
| |
| /* |
| * Various sanity checks. |
| */ |
| static void __init smp_sanity_check(void) |
| { |
| preempt_disable(); |
| |
| #if !defined(CONFIG_X86_BIGSMP) && defined(CONFIG_X86_32) |
| if (def_to_bigsmp && nr_cpu_ids > 8) { |
| unsigned int cpu; |
| unsigned nr; |
| |
| pr_warn("More than 8 CPUs detected - skipping them\n" |
| "Use CONFIG_X86_BIGSMP\n"); |
| |
| nr = 0; |
| for_each_present_cpu(cpu) { |
| if (nr >= 8) |
| set_cpu_present(cpu, false); |
| nr++; |
| } |
| |
| nr = 0; |
| for_each_possible_cpu(cpu) { |
| if (nr >= 8) |
| set_cpu_possible(cpu, false); |
| nr++; |
| } |
| |
| nr_cpu_ids = 8; |
| } |
| #endif |
| |
| if (!physid_isset(hard_smp_processor_id(), phys_cpu_present_map)) { |
| pr_warn("weird, boot CPU (#%d) not listed by the BIOS\n", |
| hard_smp_processor_id()); |
| |
| physid_set(hard_smp_processor_id(), phys_cpu_present_map); |
| } |
| |
| /* |
| * Should not be necessary because the MP table should list the boot |
| * CPU too, but we do it for the sake of robustness anyway. |
| */ |
| if (!apic->check_phys_apicid_present(boot_cpu_physical_apicid)) { |
| pr_notice("weird, boot CPU (#%d) not listed by the BIOS\n", |
| boot_cpu_physical_apicid); |
| physid_set(hard_smp_processor_id(), phys_cpu_present_map); |
| } |
| preempt_enable(); |
| } |
| |
| static void __init smp_cpu_index_default(void) |
| { |
| int i; |
| struct cpuinfo_x86 *c; |
| |
| for_each_possible_cpu(i) { |
| c = &cpu_data(i); |
| /* mark all to hotplug */ |
| c->cpu_index = nr_cpu_ids; |
| } |
| } |
| |
| static void __init smp_get_logical_apicid(void) |
| { |
| if (x2apic_mode) |
| cpu0_logical_apicid = apic_read(APIC_LDR); |
| else |
| cpu0_logical_apicid = GET_APIC_LOGICAL_ID(apic_read(APIC_LDR)); |
| } |
| |
| /* |
| * Prepare for SMP bootup. |
| * @max_cpus: configured maximum number of CPUs, It is a legacy parameter |
| * for common interface support. |
| */ |
| void __init native_smp_prepare_cpus(unsigned int max_cpus) |
| { |
| unsigned int i; |
| |
| smp_cpu_index_default(); |
| |
| /* |
| * Setup boot CPU information |
| */ |
| smp_store_boot_cpu_info(); /* Final full version of the data */ |
| cpumask_copy(cpu_callin_mask, cpumask_of(0)); |
| mb(); |
| |
| for_each_possible_cpu(i) { |
| zalloc_cpumask_var(&per_cpu(cpu_sibling_map, i), GFP_KERNEL); |
| zalloc_cpumask_var(&per_cpu(cpu_core_map, i), GFP_KERNEL); |
| zalloc_cpumask_var(&per_cpu(cpu_llc_shared_map, i), GFP_KERNEL); |
| } |
| |
| /* |
| * Set 'default' x86 topology, this matches default_topology() in that |
| * it has NUMA nodes as a topology level. See also |
| * native_smp_cpus_done(). |
| * |
| * Must be done before set_cpus_sibling_map() is ran. |
| */ |
| set_sched_topology(x86_topology); |
| |
| set_cpu_sibling_map(0); |
| |
| smp_sanity_check(); |
| |
| switch (apic_intr_mode) { |
| case APIC_PIC: |
| case APIC_VIRTUAL_WIRE_NO_CONFIG: |
| disable_smp(); |
| return; |
| case APIC_SYMMETRIC_IO_NO_ROUTING: |
| disable_smp(); |
| /* Setup local timer */ |
| x86_init.timers.setup_percpu_clockev(); |
| return; |
| case APIC_VIRTUAL_WIRE: |
| case APIC_SYMMETRIC_IO: |
| break; |
| } |
| |
| /* Setup local timer */ |
| x86_init.timers.setup_percpu_clockev(); |
| |
| smp_get_logical_apicid(); |
| |
| pr_info("CPU0: "); |
| print_cpu_info(&cpu_data(0)); |
| |
| native_pv_lock_init(); |
| |
| uv_system_init(); |
| |
| set_mtrr_aps_delayed_init(); |
| |
| smp_quirk_init_udelay(); |
| |
| speculative_store_bypass_ht_init(); |
| } |
| |
| void arch_enable_nonboot_cpus_begin(void) |
| { |
| set_mtrr_aps_delayed_init(); |
| } |
| |
| void arch_enable_nonboot_cpus_end(void) |
| { |
| mtrr_aps_init(); |
| } |
| |
| /* |
| * Early setup to make printk work. |
| */ |
| void __init native_smp_prepare_boot_cpu(void) |
| { |
| int me = smp_processor_id(); |
| switch_to_new_gdt(me); |
| /* already set me in cpu_online_mask in boot_cpu_init() */ |
| cpumask_set_cpu(me, cpu_callout_mask); |
| cpu_set_state_online(me); |
| } |
| |
| void __init calculate_max_logical_packages(void) |
| { |
| int ncpus; |
| |
| /* |
| * Today neither Intel nor AMD support heterogenous systems so |
| * extrapolate the boot cpu's data to all packages. |
| */ |
| ncpus = cpu_data(0).booted_cores * topology_max_smt_threads(); |
| __max_logical_packages = DIV_ROUND_UP(total_cpus, ncpus); |
| pr_info("Max logical packages: %u\n", __max_logical_packages); |
| } |
| |
| void __init native_smp_cpus_done(unsigned int max_cpus) |
| { |
| pr_debug("Boot done\n"); |
| |
| calculate_max_logical_packages(); |
| |
| if (x86_has_numa_in_package) |
| set_sched_topology(x86_numa_in_package_topology); |
| |
| nmi_selftest(); |
| impress_friends(); |
| mtrr_aps_init(); |
| } |
| |
| static int __initdata setup_possible_cpus = -1; |
| static int __init _setup_possible_cpus(char *str) |
| { |
| get_option(&str, &setup_possible_cpus); |
| return 0; |
| } |
| early_param("possible_cpus", _setup_possible_cpus); |
| |
| |
| /* |
| * cpu_possible_mask should be static, it cannot change as cpu's |
| * are onlined, or offlined. The reason is per-cpu data-structures |
| * are allocated by some modules at init time, and dont expect to |
| * do this dynamically on cpu arrival/departure. |
| * cpu_present_mask on the other hand can change dynamically. |
| * In case when cpu_hotplug is not compiled, then we resort to current |
| * behaviour, which is cpu_possible == cpu_present. |
| * - Ashok Raj |
| * |
| * Three ways to find out the number of additional hotplug CPUs: |
| * - If the BIOS specified disabled CPUs in ACPI/mptables use that. |
| * - The user can overwrite it with possible_cpus=NUM |
| * - Otherwise don't reserve additional CPUs. |
| * We do this because additional CPUs waste a lot of memory. |
| * -AK |
| */ |
| __init void prefill_possible_map(void) |
| { |
| int i, possible; |
| |
| /* No boot processor was found in mptable or ACPI MADT */ |
| if (!num_processors) { |
| if (boot_cpu_has(X86_FEATURE_APIC)) { |
| int apicid = boot_cpu_physical_apicid; |
| int cpu = hard_smp_processor_id(); |
| |
| pr_warn("Boot CPU (id %d) not listed by BIOS\n", cpu); |
| |
| /* Make sure boot cpu is enumerated */ |
| if (apic->cpu_present_to_apicid(0) == BAD_APICID && |
| apic->apic_id_valid(apicid)) |
| generic_processor_info(apicid, boot_cpu_apic_version); |
| } |
| |
| if (!num_processors) |
| num_processors = 1; |
| } |
| |
| i = setup_max_cpus ?: 1; |
| if (setup_possible_cpus == -1) { |
| possible = num_processors; |
| #ifdef CONFIG_HOTPLUG_CPU |
| if (setup_max_cpus) |
| possible += disabled_cpus; |
| #else |
| if (possible > i) |
| possible = i; |
| #endif |
| } else |
| possible = setup_possible_cpus; |
| |
| total_cpus = max_t(int, possible, num_processors + disabled_cpus); |
| |
| /* nr_cpu_ids could be reduced via nr_cpus= */ |
| if (possible > nr_cpu_ids) { |
| pr_warn("%d Processors exceeds NR_CPUS limit of %u\n", |
| possible, nr_cpu_ids); |
| possible = nr_cpu_ids; |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| if (!setup_max_cpus) |
| #endif |
| if (possible > i) { |
| pr_warn("%d Processors exceeds max_cpus limit of %u\n", |
| possible, setup_max_cpus); |
| possible = i; |
| } |
| |
| nr_cpu_ids = possible; |
| |
| pr_info("Allowing %d CPUs, %d hotplug CPUs\n", |
| possible, max_t(int, possible - num_processors, 0)); |
| |
| reset_cpu_possible_mask(); |
| |
| for (i = 0; i < possible; i++) |
| set_cpu_possible(i, true); |
| } |
| |
| #ifdef CONFIG_HOTPLUG_CPU |
| |
| /* Recompute SMT state for all CPUs on offline */ |
| static void recompute_smt_state(void) |
| { |
| int max_threads, cpu; |
| |
| max_threads = 0; |
| for_each_online_cpu (cpu) { |
| int threads = cpumask_weight(topology_sibling_cpumask(cpu)); |
| |
| if (threads > max_threads) |
| max_threads = threads; |
| } |
| __max_smt_threads = max_threads; |
| } |
| |
| static void remove_siblinginfo(int cpu) |
| { |
| int sibling; |
| struct cpuinfo_x86 *c = &cpu_data(cpu); |
| |
| for_each_cpu(sibling, topology_core_cpumask(cpu)) { |
| cpumask_clear_cpu(cpu, topology_core_cpumask(sibling)); |
| /*/ |
| * last thread sibling in this cpu core going down |
| */ |
| if (cpumask_weight(topology_sibling_cpumask(cpu)) == 1) |
| cpu_data(sibling).booted_cores--; |
| } |
| |
| for_each_cpu(sibling, topology_sibling_cpumask(cpu)) |
| cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling)); |
| for_each_cpu(sibling, cpu_llc_shared_mask(cpu)) |
| cpumask_clear_cpu(cpu, cpu_llc_shared_mask(sibling)); |
| cpumask_clear(cpu_llc_shared_mask(cpu)); |
| cpumask_clear(topology_sibling_cpumask(cpu)); |
| cpumask_clear(topology_core_cpumask(cpu)); |
| c->cpu_core_id = 0; |
| c->booted_cores = 0; |
| cpumask_clear_cpu(cpu, cpu_sibling_setup_mask); |
| recompute_smt_state(); |
| } |
| |
| static void remove_cpu_from_maps(int cpu) |
| { |
| set_cpu_online(cpu, false); |
| cpumask_clear_cpu(cpu, cpu_callout_mask); |
| cpumask_clear_cpu(cpu, cpu_callin_mask); |
| /* was set by cpu_init() */ |
| cpumask_clear_cpu(cpu, cpu_initialized_mask); |
| numa_remove_cpu(cpu); |
| } |
| |
| void cpu_disable_common(void) |
| { |
| int cpu = smp_processor_id(); |
| |
| remove_siblinginfo(cpu); |
| |
| /* It's now safe to remove this processor from the online map */ |
| lock_vector_lock(); |
| remove_cpu_from_maps(cpu); |
| unlock_vector_lock(); |
| fixup_irqs(); |
| lapic_offline(); |
| } |
| |
| int native_cpu_disable(void) |
| { |
| int ret; |
| |
| ret = lapic_can_unplug_cpu(); |
| if (ret) |
| return ret; |
| |
| clear_local_APIC(); |
| cpu_disable_common(); |
| |
| return 0; |
| } |
| |
| int common_cpu_die(unsigned int cpu) |
| { |
| int ret = 0; |
| |
| /* We don't do anything here: idle task is faking death itself. */ |
| |
| /* They ack this in play_dead() by setting CPU_DEAD */ |
| if (cpu_wait_death(cpu, 5)) { |
| if (system_state == SYSTEM_RUNNING) |
| pr_info("CPU %u is now offline\n", cpu); |
| } else { |
| pr_err("CPU %u didn't die...\n", cpu); |
| ret = -1; |
| } |
| |
| return ret; |
| } |
| |
| void native_cpu_die(unsigned int cpu) |
| { |
| common_cpu_die(cpu); |
| } |
| |
| void play_dead_common(void) |
| { |
| idle_task_exit(); |
| |
| /* Ack it */ |
| (void)cpu_report_death(); |
| |
| /* |
| * With physical CPU hotplug, we should halt the cpu |
| */ |
| local_irq_disable(); |
| } |
| |
| static bool wakeup_cpu0(void) |
| { |
| if (smp_processor_id() == 0 && enable_start_cpu0) |
| return true; |
| |
| return false; |
| } |
| |
| /* |
| * We need to flush the caches before going to sleep, lest we have |
| * dirty data in our caches when we come back up. |
| */ |
| static inline void mwait_play_dead(void) |
| { |
| unsigned int eax, ebx, ecx, edx; |
| unsigned int highest_cstate = 0; |
| unsigned int highest_subcstate = 0; |
| void *mwait_ptr; |
| int i; |
| |
| if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD || |
| boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) |
| return; |
| if (!this_cpu_has(X86_FEATURE_MWAIT)) |
| return; |
| if (!this_cpu_has(X86_FEATURE_CLFLUSH)) |
| return; |
| if (__this_cpu_read(cpu_info.cpuid_level) < CPUID_MWAIT_LEAF) |
| return; |
| |
| eax = CPUID_MWAIT_LEAF; |
| ecx = 0; |
| native_cpuid(&eax, &ebx, &ecx, &edx); |
| |
| /* |
| * eax will be 0 if EDX enumeration is not valid. |
| * Initialized below to cstate, sub_cstate value when EDX is valid. |
| */ |
| if (!(ecx & CPUID5_ECX_EXTENSIONS_SUPPORTED)) { |
| eax = 0; |
| } else { |
| edx >>= MWAIT_SUBSTATE_SIZE; |
| for (i = 0; i < 7 && edx; i++, edx >>= MWAIT_SUBSTATE_SIZE) { |
| if (edx & MWAIT_SUBSTATE_MASK) { |
| highest_cstate = i; |
| highest_subcstate = edx & MWAIT_SUBSTATE_MASK; |
| } |
| } |
| eax = (highest_cstate << MWAIT_SUBSTATE_SIZE) | |
| (highest_subcstate - 1); |
| } |
| |
| /* |
| * This should be a memory location in a cache line which is |
| * unlikely to be touched by other processors. The actual |
| * content is immaterial as it is not actually modified in any way. |
| */ |
| mwait_ptr = ¤t_thread_info()->flags; |
| |
| wbinvd(); |
| |
| while (1) { |
| /* |
| * The CLFLUSH is a workaround for erratum AAI65 for |
| * the Xeon 7400 series. It's not clear it is actually |
| * needed, but it should be harmless in either case. |
| * The WBINVD is insufficient due to the spurious-wakeup |
| * case where we return around the loop. |
| */ |
| mb(); |
| clflush(mwait_ptr); |
| mb(); |
| __monitor(mwait_ptr, 0, 0); |
| mb(); |
| __mwait(eax, 0); |
| /* |
| * If NMI wants to wake up CPU0, start CPU0. |
| */ |
| if (wakeup_cpu0()) |
| start_cpu0(); |
| } |
| } |
| |
| void hlt_play_dead(void) |
| { |
| if (__this_cpu_read(cpu_info.x86) >= 4) |
| wbinvd(); |
| |
| while (1) { |
| native_halt(); |
| /* |
| * If NMI wants to wake up CPU0, start CPU0. |
| */ |
| if (wakeup_cpu0()) |
| start_cpu0(); |
| } |
| } |
| |
| void native_play_dead(void) |
| { |
| play_dead_common(); |
| tboot_shutdown(TB_SHUTDOWN_WFS); |
| |
| mwait_play_dead(); /* Only returns on failure */ |
| if (cpuidle_play_dead()) |
| hlt_play_dead(); |
| } |
| |
| #else /* ... !CONFIG_HOTPLUG_CPU */ |
| int native_cpu_disable(void) |
| { |
| return -ENOSYS; |
| } |
| |
| void native_cpu_die(unsigned int cpu) |
| { |
| /* We said "no" in __cpu_disable */ |
| BUG(); |
| } |
| |
| void native_play_dead(void) |
| { |
| BUG(); |
| } |
| |
| #endif |