cregit-Linux how code gets into the kernel

Release 4.14 arch/powerpc/kernel/smp.c

/*
 * SMP support for ppc.
 *
 * Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
 * deal of code from the sparc and intel versions.
 *
 * Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
 *
 * PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and
 * Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */


#undef DEBUG

#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/sched/mm.h>
#include <linux/sched/topology.h>
#include <linux/smp.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/cache.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/cpu.h>
#include <linux/notifier.h>
#include <linux/topology.h>
#include <linux/profile.h>
#include <linux/processor.h>

#include <asm/ptrace.h>
#include <linux/atomic.h>
#include <asm/irq.h>
#include <asm/hw_irq.h>
#include <asm/kvm_ppc.h>
#include <asm/dbell.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/prom.h>
#include <asm/smp.h>
#include <asm/time.h>
#include <asm/machdep.h>
#include <asm/cputhreads.h>
#include <asm/cputable.h>
#include <asm/mpic.h>
#include <asm/vdso_datapage.h>
#ifdef CONFIG_PPC64
#include <asm/paca.h>
#endif
#include <asm/vdso.h>
#include <asm/debug.h>
#include <asm/kexec.h>
#include <asm/asm-prototypes.h>
#include <asm/cpu_has_feature.h>

#ifdef DEBUG
#include <asm/udbg.h>

#define DBG(fmt...) udbg_printf(fmt)
#else

#define DBG(fmt...)
#endif

#ifdef CONFIG_HOTPLUG_CPU
/* State of each CPU during hotplug phases */
static DEFINE_PER_CPU(int, cpu_state) = { 0 };
#endif


struct thread_info *secondary_ti;

DEFINE_PER_CPU(cpumask_var_t, cpu_sibling_map);
DEFINE_PER_CPU(cpumask_var_t, cpu_l2_cache_map);
DEFINE_PER_CPU(cpumask_var_t, cpu_core_map);


EXPORT_PER_CPU_SYMBOL(cpu_sibling_map);

EXPORT_PER_CPU_SYMBOL(cpu_l2_cache_map);

EXPORT_PER_CPU_SYMBOL(cpu_core_map);

/* SMP operations for this machine */

struct smp_ops_t *smp_ops;

/* Can't be static due to PowerMac hackery */

volatile unsigned int cpu_callin_map[NR_CPUS];


int smt_enabled_at_boot = 1;

/*
 * Returns 1 if the specified cpu should be brought up during boot.
 * Used to inhibit booting threads if they've been disabled or
 * limited on the command line
 */

int smp_generic_cpu_bootable(unsigned int nr) { /* Special case - we inhibit secondary thread startup * during boot if the user requests it. */ if (system_state < SYSTEM_RUNNING && cpu_has_feature(CPU_FTR_SMT)) { if (!smt_enabled_at_boot && cpu_thread_in_core(nr) != 0) return 0; if (smt_enabled_at_boot && cpu_thread_in_core(nr) >= smt_enabled_at_boot) return 0; } return 1; }

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Andy Fleming5396.36%150.00%
Thomas Gleixner23.64%150.00%
Total55100.00%2100.00%

#ifdef CONFIG_PPC64
int smp_generic_kick_cpu(int nr) { if (nr < 0 || nr >= nr_cpu_ids) return -EINVAL; /* * The processor is currently spinning, waiting for the * cpu_start field to become non-zero After we set cpu_start, * the processor will continue on to secondary_start */ if (!paca[nr].cpu_start) { paca[nr].cpu_start = 1; smp_mb(); return 0; } #ifdef CONFIG_HOTPLUG_CPU /* * Ok it's not there, so it might be soft-unplugged, let's * try to bring it back */ generic_set_cpu_up(nr); smp_wmb(); smp_send_reschedule(nr); #endif /* CONFIG_HOTPLUG_CPU */ return 0; }

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Benjamin Herrenschmidt4865.75%220.00%
Anton Blanchard1216.44%440.00%
Santosh Sivaraj810.96%220.00%
Michael Ellerman45.48%110.00%
Chen-Hui Zhao11.37%110.00%
Total73100.00%10100.00%

#endif /* CONFIG_PPC64 */
static irqreturn_t call_function_action(int irq, void *data) { generic_smp_call_function_interrupt(); return IRQ_HANDLED; }

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Milton D. Miller II19100.00%1100.00%
Total19100.00%1100.00%


static irqreturn_t reschedule_action(int irq, void *data) { scheduler_ipi(); return IRQ_HANDLED; }

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Milton D. Miller II1684.21%150.00%
Peter Zijlstra315.79%150.00%
Total19100.00%2100.00%


static irqreturn_t tick_broadcast_ipi_action(int irq, void *data) { tick_broadcast_ipi_handler(); return IRQ_HANDLED; }

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Milton D. Miller II1578.95%150.00%
Srivatsa S. Bhat421.05%150.00%
Total19100.00%2100.00%

#ifdef CONFIG_NMI_IPI
static irqreturn_t nmi_ipi_action(int irq, void *data) { smp_handle_nmi_ipi(get_irq_regs()); return IRQ_HANDLED; }

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Milton D. Miller II2090.91%375.00%
Nicholas Piggin29.09%125.00%
Total22100.00%4100.00%

#endif static irq_handler_t smp_ipi_action[] = { [PPC_MSG_CALL_FUNCTION] = call_function_action, [PPC_MSG_RESCHEDULE] = reschedule_action, [PPC_MSG_TICK_BROADCAST] = tick_broadcast_ipi_action, #ifdef CONFIG_NMI_IPI [PPC_MSG_NMI_IPI] = nmi_ipi_action, #endif }; /* * The NMI IPI is a fallback and not truly non-maskable. It is simpler * than going through the call function infrastructure, and strongly * serialized, so it is more appropriate for debugging. */ const char *smp_ipi_name[] = { [PPC_MSG_CALL_FUNCTION] = "ipi call function", [PPC_MSG_RESCHEDULE] = "ipi reschedule", [PPC_MSG_TICK_BROADCAST] = "ipi tick-broadcast", [PPC_MSG_NMI_IPI] = "nmi ipi", }; /* optional function to request ipi, for controllers with >= 4 ipis */
int smp_request_message_ipi(int virq, int msg) { int err; if (msg < 0 || msg > PPC_MSG_NMI_IPI) return -EINVAL; #ifndef CONFIG_NMI_IPI if (msg == PPC_MSG_NMI_IPI) return 1; #endif err = request_irq(virq, smp_ipi_action[msg], IRQF_PERCPU | IRQF_NO_THREAD | IRQF_NO_SUSPEND, smp_ipi_name[msg], NULL); WARN(err < 0, "unable to request_irq %d for %s (rc %d)\n", virq, smp_ipi_name[msg], err); return err; }

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Milton D. Miller II7888.64%120.00%
Nicholas Piggin55.68%120.00%
Thomas Gleixner22.27%120.00%
Chen-Hui Zhao22.27%120.00%
Anton Blanchard11.14%120.00%
Total88100.00%5100.00%

#ifdef CONFIG_PPC_SMP_MUXED_IPI struct cpu_messages { long messages; /* current messages */ }; static DEFINE_PER_CPU_SHARED_ALIGNED(struct cpu_messages, ipi_message);
void smp_muxed_ipi_set_message(int cpu, int msg) { struct cpu_messages *info = &per_cpu(ipi_message, cpu); char *message = (char *)&info->messages; /* * Order previous accesses before accesses in the IPI handler. */ smp_mb(); message[msg] = 1; }

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Milton D. Miller II4287.50%250.00%
Paul Mackerras48.33%125.00%
Suresh E. Warrier24.17%125.00%
Total48100.00%4100.00%


void smp_muxed_ipi_message_pass(int cpu, int msg) { smp_muxed_ipi_set_message(cpu, msg); /* * cause_ipi functions are required to include a full barrier * before doing whatever causes the IPI. */ smp_ops->cause_ipi(cpu); }

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Suresh E. Warrier1765.38%133.33%
Milton D. Miller II830.77%133.33%
Paul Mackerras13.85%133.33%
Total26100.00%3100.00%

#ifdef __BIG_ENDIAN__ #define IPI_MESSAGE(A) (1uL << ((BITS_PER_LONG - 8) - 8 * (A))) #else #define IPI_MESSAGE(A) (1uL << (8 * (A))) #endif
irqreturn_t smp_ipi_demux(void) { mb(); /* order any irq clear */ return smp_ipi_demux_relaxed(); }

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Nicholas Piggin960.00%150.00%
Milton D. Miller II640.00%150.00%
Total15100.00%2100.00%

/* sync-free variant. Callers should ensure synchronization */
irqreturn_t smp_ipi_demux_relaxed(void) { struct cpu_messages *info; unsigned long all; info = this_cpu_ptr(&ipi_message); do { all = xchg(&info->messages, 0); #if defined(CONFIG_KVM_XICS) && defined(CONFIG_KVM_BOOK3S_HV_POSSIBLE) /* * Must check for PPC_MSG_RM_HOST_ACTION messages * before PPC_MSG_CALL_FUNCTION messages because when * a VM is destroyed, we call kick_all_cpus_sync() * to ensure that any pending PPC_MSG_RM_HOST_ACTION * messages have completed before we free any VCPUs. */ if (all & IPI_MESSAGE(PPC_MSG_RM_HOST_ACTION)) kvmppc_xics_ipi_action(); #endif if (all & IPI_MESSAGE(PPC_MSG_CALL_FUNCTION)) generic_smp_call_function_interrupt(); if (all & IPI_MESSAGE(PPC_MSG_RESCHEDULE)) scheduler_ipi(); if (all & IPI_MESSAGE(PPC_MSG_TICK_BROADCAST)) tick_broadcast_ipi_handler(); #ifdef CONFIG_NMI_IPI if (all & IPI_MESSAGE(PPC_MSG_NMI_IPI)) nmi_ipi_action(0, NULL); #endif } while (info->messages); return IRQ_HANDLED; }

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PersonTokensPropCommitsCommitProp
Milton D. Miller II6146.21%218.18%
Suresh E. Warrier2720.45%218.18%
Nicholas Piggin2015.15%327.27%
Srivatsa S. Bhat129.09%19.09%
Anton Blanchard96.82%19.09%
Benjamin Herrenschmidt21.52%19.09%
Paul Mackerras10.76%19.09%
Total132100.00%11100.00%

#endif /* CONFIG_PPC_SMP_MUXED_IPI */
static inline void do_message_pass(int cpu, int msg) { if (smp_ops->message_pass) smp_ops->message_pass(cpu, msg); #ifdef CONFIG_PPC_SMP_MUXED_IPI else smp_muxed_ipi_message_pass(cpu, msg); #endif }

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Paul Mackerras41100.00%1100.00%
Total41100.00%1100.00%


void smp_send_reschedule(int cpu) { if (likely(smp_ops)) do_message_pass(cpu, PPC_MSG_RESCHEDULE); }

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Will Schmidt1359.09%125.00%
Jens Axboe627.27%125.00%
Anton Blanchard29.09%125.00%
Paul Mackerras14.55%125.00%
Total22100.00%4100.00%

EXPORT_SYMBOL_GPL(smp_send_reschedule);
void arch_send_call_function_single_ipi(int cpu) { do_message_pass(cpu, PPC_MSG_CALL_FUNCTION); }

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Jens Axboe640.00%114.29%
Will Schmidt320.00%114.29%
Avi Kivity213.33%114.29%
Hugh Dickins16.67%114.29%
Paul Mackerras16.67%114.29%
Srivatsa S. Bhat16.67%114.29%
Olof Johansson16.67%114.29%
Total15100.00%7100.00%


void arch_send_call_function_ipi_mask(const struct cpumask *mask) { unsigned int cpu; for_each_cpu(cpu, mask) do_message_pass(cpu, PPC_MSG_CALL_FUNCTION); }

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Jens Axboe932.14%120.00%
Olof Johansson725.00%120.00%
Rusty Russell621.43%120.00%
Satyam Sharma517.86%120.00%
Paul Mackerras13.57%120.00%
Total28100.00%5100.00%

#ifdef CONFIG_NMI_IPI /* * "NMI IPI" system. * * NMI IPIs may not be recoverable, so should not be used as ongoing part of * a running system. They can be used for crash, debug, halt/reboot, etc. * * NMI IPIs are globally single threaded. No more than one in progress at * any time. * * The IPI call waits with interrupts disabled until all targets enter the * NMI handler, then the call returns. * * No new NMI can be initiated until targets exit the handler. * * The IPI call may time out without all targets entering the NMI handler. * In that case, there is some logic to recover (and ignore subsequent * NMI interrupts that may eventually be raised), but the platform interrupt * handler may not be able to distinguish this from other exception causes, * which may cause a crash. */ static atomic_t __nmi_ipi_lock = ATOMIC_INIT(0); static struct cpumask nmi_ipi_pending_mask; static int nmi_ipi_busy_count = 0; static void (*nmi_ipi_function)(struct pt_regs *) = NULL;
static void nmi_ipi_lock_start(unsigned long *flags) { raw_local_irq_save(*flags); hard_irq_disable(); while (atomic_cmpxchg(&__nmi_ipi_lock, 0, 1) == 1) { raw_local_irq_restore(*flags); spin_until_cond(atomic_read(&__nmi_ipi_lock) == 0); raw_local_irq_save(*flags); hard_irq_disable(); } }

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Nicholas Piggin5182.26%250.00%
Srivatsa S. Bhat812.90%125.00%
Milton D. Miller II34.84%125.00%
Total62100.00%4100.00%


static void nmi_ipi_lock(void) { while (atomic_cmpxchg(&__nmi_ipi_lock, 0, 1) == 1) spin_until_cond(atomic_read(&__nmi_ipi_lock) == 0); }

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Nicholas Piggin2472.73%240.00%
Jens Axboe412.12%120.00%
Milton D. Miller II39.09%120.00%
Olof Johansson26.06%120.00%
Total33100.00%5100.00%


static void nmi_ipi_unlock(void) { smp_mb(); WARN_ON(atomic_read(&__nmi_ipi_lock) != 1); atomic_set(&__nmi_ipi_lock, 0); }

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Nicholas Piggin1756.67%120.00%
Jens Axboe516.67%120.00%
Milton D. Miller II413.33%120.00%
Satyam Sharma310.00%120.00%
Olof Johansson13.33%120.00%
Total30100.00%5100.00%


static void nmi_ipi_unlock_end(unsigned long *flags) { nmi_ipi_unlock(); raw_local_irq_restore(*flags); }

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Nicholas Piggin1680.00%150.00%
Anton Blanchard420.00%150.00%
Total20100.00%2100.00%

/* * Platform NMI handler calls this to ack */
int smp_handle_nmi_ipi(struct pt_regs *regs) { void (*fn)(struct pt_regs *); unsigned long flags; int me = raw_smp_processor_id(); int ret = 0; /* * Unexpected NMIs are possible here because the interrupt may not * be able to distinguish NMI IPIs from other types of NMIs, or * because the caller may have timed out. */ nmi_ipi_lock_start(&flags); if (!nmi_ipi_busy_count) goto out; if (!cpumask_test_cpu(me, &nmi_ipi_pending_mask)) goto out; fn = nmi_ipi_function; if (!fn) goto out; cpumask_clear_cpu(me, &nmi_ipi_pending_mask); nmi_ipi_busy_count++; nmi_ipi_unlock(); ret = 1; fn(regs); nmi_ipi_lock(); nmi_ipi_busy_count--; out: nmi_ipi_unlock_end(&flags); return ret; }

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Nicholas Piggin9883.76%116.67%
Milton D. Miller II97.69%116.67%
Andrew Morton54.27%233.33%
Jens Axboe32.56%116.67%
Olof Johansson21.71%116.67%
Total117100.00%6100.00%


static void do_smp_send_nmi_ipi(int cpu) { if (smp_ops->cause_nmi_ipi && smp_ops->cause_nmi_ipi(cpu)) return; if (cpu >= 0) { do_message_pass(cpu, PPC_MSG_NMI_IPI); } else { int c; for_each_online_cpu(c) { if (c == raw_smp_processor_id()) continue; do_message_pass(c, PPC_MSG_NMI_IPI); } } }

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Nicholas Piggin5381.54%233.33%
Milton D. Miller II69.23%116.67%
Jens Axboe34.62%116.67%
Andrew Morton23.08%116.67%
Olof Johansson11.54%116.67%
Total65100.00%6100.00%


void smp_flush_nmi_ipi(u64 delay_us) { unsigned long flags; nmi_ipi_lock_start(&flags); while (nmi_ipi_busy_count) { nmi_ipi_unlock_end(&flags); udelay(1); if (delay_us) { delay_us--; if (!delay_us) return; } nmi_ipi_lock_start(&flags); } nmi_ipi_unlock_end(&flags); }

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Nicholas Piggin62100.00%1100.00%
Total62100.00%1100.00%

/* * - cpu is the target CPU (must not be this CPU), or NMI_IPI_ALL_OTHERS. * - fn is the target callback function. * - delay_us > 0 is the delay before giving up waiting for targets to * enter the handler, == 0 specifies indefinite delay. */
int smp_send_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), u64 delay_us) { unsigned long flags; int me = raw_smp_processor_id(); int ret = 1; BUG_ON(cpu == me); BUG_ON(cpu < 0 && cpu != NMI_IPI_ALL_OTHERS); if (unlikely(!smp_ops)) return 0; /* Take the nmi_ipi_busy count/lock with interrupts hard disabled */ nmi_ipi_lock_start(&flags); while (nmi_ipi_busy_count) { nmi_ipi_unlock_end(&flags); spin_until_cond(nmi_ipi_busy_count == 0); nmi_ipi_lock_start(&flags); } nmi_ipi_function = fn; if (cpu < 0) { /* ALL_OTHERS */ cpumask_copy(&nmi_ipi_pending_mask, cpu_online_mask); cpumask_clear_cpu(me, &nmi_ipi_pending_mask); } else { /* cpumask starts clear */ cpumask_set_cpu(cpu, &nmi_ipi_pending_mask); } nmi_ipi_busy_count++; nmi_ipi_unlock(); do_smp_send_nmi_ipi(cpu); while (!cpumask_empty(&nmi_ipi_pending_mask)) { udelay(1); if (delay_us) { delay_us--; if (!delay_us) break; } } nmi_ipi_lock(); if (!cpumask_empty(&nmi_ipi_pending_mask)) { /* Could not gather all CPUs */ ret = 0; cpumask_clear(&nmi_ipi_pending_mask); } nmi_ipi_busy_count--; nmi_ipi_unlock_end(&flags); return ret; }

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Nicholas Piggin21397.71%250.00%
Milton D. Miller II41.83%125.00%
Anton Blanchard10.46%125.00%
Total218100.00%4100.00%

#endif /* CONFIG_NMI_IPI */ #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
void tick_broadcast(const struct cpumask *mask) { unsigned int cpu; for_each_cpu(cpu, mask) do_message_pass(cpu, PPC_MSG_TICK_BROADCAST); }

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Nicholas Piggin2485.71%125.00%
Jens Axboe27.14%125.00%
Olof Johansson13.57%125.00%
Paul Mackerras13.57%125.00%
Total28100.00%4100.00%

#endif #ifdef CONFIG_DEBUGGER
void debugger_ipi_callback(struct pt_regs *regs) { debugger_ipi(regs); }

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Nicholas Piggin1493.33%150.00%
Jens Axboe16.67%150.00%
Total15100.00%2100.00%


void smp_send_debugger_break(void) { smp_send_nmi_ipi(NMI_IPI_ALL_OTHERS, debugger_ipi_callback, 1000000); }

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Nicholas Piggin1381.25%150.00%
Satyam Sharma318.75%150.00%
Total16100.00%2100.00%

#endif #ifdef CONFIG_KEXEC_CORE
void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *)) { smp_send_nmi_ipi(NMI_IPI_ALL_OTHERS, crash_ipi_callback, 1000000); }

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Anton Blanchard1040.00%133.33%
Jens Axboe832.00%133.33%
Nicholas Piggin728.00%133.33%
Total25100.00%3100.00%

#endif
static void stop_this_cpu(void *dummy) { /* Remove this CPU */ set_cpu_online(smp_processor_id(), false); local_irq_disable(); while (1) ; }

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Jens Axboe1451.85%133.33%
Valentine Barshak933.33%133.33%
Anton Blanchard414.81%133.33%
Total27100.00%3100.00%


void smp_send_stop(void) { smp_call_function(stop_this_cpu, NULL, 0); }

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Jens Axboe1168.75%133.33%
Andrew Morton531.25%266.67%
Total16100.00%3100.00%

struct thread_info *current_set[NR_CPUS];
static void smp_store_cpu_info(int id) { per_cpu(cpu_pvr, id) = mfspr(SPRN_PVR); #ifdef CONFIG_PPC_FSL_BOOK3E per_cpu(next_tlbcam_idx, id) = (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; #endif }

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Becky Bruce2352.27%125.00%
Andrew Morton1636.36%125.00%
Benjamin Herrenschmidt49.09%125.00%
Tejun Heo12.27%125.00%
Total44100.00%4100.00%

/* * Relationships between CPUs are maintained in a set of per-cpu cpumasks so * rather than just passing around the cpumask we pass around a function that * returns the that cpumask for the given CPU. */ static void set_cpus_related(int i, int j, struct cpumask *(*get_cpumask)(int)) { cpumask_set_cpu(i, get_cpumask(j)); cpumask_set_cpu(j, get_cpumask(i)); } #ifdef CONFIG_HOTPLUG_CPU static void set_cpus_unrelated(int i, int j, struct cpumask *(*get_cpumask)(int)) { cpumask_clear_cpu(i, get_cpumask(j)); cpumask_clear_cpu(j, get_cpumask(i)); } #endif
void __init smp_prepare_cpus(unsigned int max_cpus) { unsigned int cpu; DBG("smp_prepare_cpus\n"); /* * setup_cpu may need to be called on the boot cpu. We havent * spun any cpus up but lets be paranoid. */ BUG_ON(boot_cpuid != smp_processor_id()); /* Fixup boot cpu */ smp_store_cpu_info(boot_cpuid); cpu_callin_map[boot_cpuid] = 1; for_each_possible_cpu(cpu) { zalloc_cpumask_var_node(&per_cpu(cpu_sibling_map, cpu), GFP_KERNEL, cpu_to_node(cpu)); zalloc_cpumask_var_node(&per_cpu(cpu_l2_cache_map, cpu), GFP_KERNEL, cpu_to_node(cpu)); zalloc_cpumask_var_node(&per_cpu(cpu_core_map, cpu), GFP_KERNEL, cpu_to_node(cpu)); /* * numa_node_id() works after this. */ if (cpu_present(cpu)) { set_cpu_numa_node(cpu, numa_cpu_lookup_table[cpu]); set_cpu_numa_mem(cpu, local_memory_node(numa_cpu_lookup_table[cpu])); } } /* Init the cpumasks so the boot CPU is related to itself */ cpumask_set_cpu(boot_cpuid, cpu_sibling_mask(boot_cpuid)); cpumask_set_cpu(boot_cpuid, cpu_l2_cache_mask(boot_cpuid)); cpumask_set_cpu(boot_cpuid, cpu_core_mask(boot_cpuid)); if (smp_ops && smp_ops->probe) smp_ops->probe(); }

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Anton Blanchard8849.44%428.57%
Oliver O'Halloran2916.29%214.29%
Nishanth Aravamudan2413.48%17.14%
Andrew Morton158.43%214.29%
Li Zhong95.06%17.14%
Benjamin Herrenschmidt84.49%214.29%
Kumar Gala42.25%17.14%
Chen Gang S10.56%17.14%
Total178100.00%14100.00%


void smp_prepare_boot_cpu(void) { BUG_ON(smp_processor_id() != boot_cpuid); #ifdef CONFIG_PPC64 paca[boot_cpuid].__current = current; #endif set_numa_node(numa_cpu_lookup_table[boot_cpuid]); current_set[boot_cpuid] = task_thread_info(current); }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Morton3063.83%233.33%
Nishanth Aravamudan817.02%116.67%
Paul Mackerras510.64%116.67%
Al Viro36.38%116.67%
David Gibson12.13%116.67%
Total47100.00%6100.00%

#ifdef CONFIG_HOTPLUG_CPU
int generic_cpu_disable(void) { unsigned int cpu = smp_processor_id(); if (cpu == boot_cpuid) return -EBUSY; set_cpu_online(cpu, false); #ifdef CONFIG_PPC64 vdso_data->processorCount--; #endif /* Update affinity of all IRQs previously aimed at this CPU */ irq_migrate_all_off_this_cpu(); /* * Depending on the details of the interrupt controller, it's possible * that one of the interrupts we just migrated away from this CPU is * actually already pending on this CPU. If we leave it in that state * the interrupt will never be EOI'ed, and will never fire again. So * temporarily enable interrupts here, to allow any pending interrupt to * be received (and EOI'ed), before we take this CPU offline. */ local_irq_enable(); mdelay(1); local_irq_disable(); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Zwane Mwaikambo3660.00%112.50%
Benjamin Herrenschmidt1626.67%337.50%
Paul Mackerras58.33%225.00%
Rusty Russell23.33%112.50%
Michael Ellerman11.67%112.50%
Total60100.00%8100.00%


void generic_cpu_die(unsigned int cpu) { int i; for (i = 0; i < 100; i++) { smp_rmb(); if (is_cpu_dead(cpu)) return; msleep(100); } printk(KERN_ERR "CPU%d didn't die...\n", cpu); }

Contributors

PersonTokensPropCommitsCommitProp
Zwane Mwaikambo4996.08%133.33%
Chen-Hui Zhao11.96%133.33%
Anton Blanchard11.96%133.33%
Total51100.00%3100.00%


void generic_set_cpu_dead(unsigned int cpu) { per_cpu(cpu_state, cpu) = CPU_DEAD; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt18100.00%1100.00%
Total18100.00%1100.00%

/* * The cpu_state should be set to CPU_UP_PREPARE in kick_cpu(), otherwise * the cpu_state is always CPU_DEAD after calling generic_set_cpu_dead(), * which makes the delay in generic_cpu_die() not happen. */
void generic_set_cpu_up(unsigned int cpu) { per_cpu(cpu_state, cpu) = CPU_UP_PREPARE; }

Contributors

PersonTokensPropCommitsCommitProp
Chen-Hui Zhao18100.00%1100.00%
Total18100.00%1100.00%


int generic_check_cpu_restart(unsigned int cpu) { return per_cpu(cpu_state, cpu) == CPU_UP_PREPARE; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt19100.00%1100.00%
Total19100.00%1100.00%


int is_cpu_dead(unsigned int cpu) { return per_cpu(cpu_state, cpu) == CPU_DEAD; }

Contributors

PersonTokensPropCommitsCommitProp
Chen-Hui Zhao19100.00%1100.00%
Total19100.00%1100.00%


static bool secondaries_inhibited(void) { return kvm_hv_mode_active(); }

Contributors

PersonTokensPropCommitsCommitProp
Paul Mackerras975.00%150.00%
Michael Ellerman325.00%150.00%
Total12100.00%2100.00%

#else /* HOTPLUG_CPU */ #define secondaries_inhibited() 0 #endif
static void cpu_idle_thread_init(unsigned int cpu, struct task_struct *idle) { struct thread_info *ti = task_thread_info(idle); #ifdef CONFIG_PPC64 paca[cpu].__current = idle; paca[cpu].kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD; #endif ti->cpu = cpu; secondary_ti = current_set[cpu] = ti; }

Contributors

PersonTokensPropCommitsCommitProp
Benjamin Herrenschmidt6287.32%150.00%
Thomas Gleixner912.68%150.00%
Total71100.00%2100.00%


int __cpu_up(unsigned int cpu, struct task_struct *tidle) { int rc, c; /* * Don't allow secondary threads to come online if inhibited */ if (threads_per_core > 1 && secondaries_inhibited() && cpu_thread_in_subcore(cpu)) return -EBUSY; if (smp_ops == NULL || (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu))) return -EINVAL; cpu_idle_thread_init(cpu, tidle); /* * The platform might need to allocate resources prior to bringing * up the CPU */ if (smp_ops->prepare_cpu) { rc = smp_ops->prepare_cpu(cpu); if (rc) return rc; } /* Make sure callin-map entry is 0 (can be leftover a CPU * hotplug */ cpu_callin_map[cpu] = 0; /* The information for processor bringup must * be written out to main store before we release * the processor. */ smp_mb(); /* wake up cpus */ DBG("smp: kicking cpu %d\n", cpu); rc = smp_ops->kick_cpu(cpu); if (rc) { pr_err("smp: failed starting cpu %d (rc %d)\n", cpu, rc); return rc; } /* * wait to see if the cpu made a callin (is actually up). * use this value that I found through experimentation. * -- Cort */ if (system_state < SYSTEM_RUNNING) for (c = 50000; c && !cpu_callin_map[cpu]; c--) udelay(100); #ifdef CONFIG_HOTPLUG_CPU else /* * CPUs can take much longer to come up in the * hotplug case. Wait five seconds. */ for (c = 5000; c && !cpu_callin_map[cpu]; c--) msleep(1); #endif if (!cpu_callin_map[cpu]) { printk(KERN_ERR "Processor %u is stuck.\n", cpu); return -ENOENT; } DBG("Processor %u found.\n", cpu); if (smp_ops->give_timebase) smp_ops->give_timebase(); /* Wait until cpu puts itself in the online & active maps */ spin_until_cond(cpu_online(cpu)); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Blanchard9035.86%416.00%
Benjamin Herrenschmidt5220.72%416.00%
Andrew Morton4216.73%312.00%
Paul Mackerras249.56%312.00%
Michael Ellerman249.56%312.00%
Thomas Gleixner83.19%28.00%
Nicholas Piggin31.20%14.00%
Zwane Mwaikambo20.80%14.00%
Darren Hart20.80%14.00%
Gautham R. Shenoy20.80%14.00%
Jon Loeliger10.40%14.00%
Srivatsa Vaddagiri10.40%14.00%
Total251100.00%25100.00%

/* Return the value of the reg property corresponding to the given * logical cpu. */
int cpu_to_core_id(int cpu) { struct device_node *np; const __be32 *reg; int id = -1; np = of_get_cpu_node(cpu, NULL); if (!np) goto out; reg = of_get_property(np, "reg", NULL); if (!reg) goto out; id = be32_to_cpup(reg); out: of_node_put(np); return id; }

Contributors

PersonTokensPropCommitsCommitProp
Nathan T. Lynch7394.81%150.00%
Anton Blanchard45.19%150.00%
Total77100.00%2100.00%

EXPORT_SYMBOL_GPL(cpu_to_core_id); /* Helper routines for cpu to core mapping */
int cpu_core_index_of_thread(int cpu) { return cpu >> threads_shift; }

Contributors

PersonTokensPropCommitsCommitProp
Vaidyanathan Srinivasan13100.00%1100.00%
Total13100.00%1100.00%

EXPORT_SYMBOL_GPL(cpu_core_index_of_thread);
int cpu_first_thread_of_core(int core) { return core << threads_shift; }

Contributors

PersonTokensPropCommitsCommitProp
Vaidyanathan Srinivasan13100.00%1100.00%
Total13100.00%1100.00%

EXPORT_SYMBOL_GPL(cpu_first_thread_of_core); /* Must be called when no change can occur to cpu_present_mask, * i.e. during cpu online or offline. */
static struct device_node *cpu_to_l2cache(int cpu) { struct device_node *np; struct device_node *cache; if (!cpu_present(cpu)) return NULL; np = of_get_cpu_node(cpu, NULL); if (np == NULL) return NULL; cache = of_find_next_cache_node(np); of_node_put(np); return cache; }

Contributors

PersonTokensPropCommitsCommitProp
Nathan T. Lynch65100.00%2100.00%
Total65100.00%2100.00%

static bool update_mask_by_l2(int cpu, struct cpumask *(*mask_fn)(int)) { struct device_node *l2_cache, *np; int i; l2_cache = cpu_to_l2cache(cpu); if (!l2_cache) return false; for_each_cpu(i, cpu_online_mask) { /* * when updating the marks the current CPU has not been marked * online, but we need to update the cache masks */ np = cpu_to_l2cache(i); if (!np) continue; if (np == l2_cache) set_cpus_related(cpu, i, mask_fn); of_node_put(np); } of_node_put(l2_cache); return true; } #ifdef CONFIG_HOTPLUG_CPU
static void remove_cpu_from_masks(int cpu) { int i; /* NB: cpu_core_mask is a superset of the others */ for_each_cpu(i, cpu_core_mask(cpu)) { set_cpus_unrelated(cpu, i, cpu_core_mask); set_cpus_unrelated(cpu, i, cpu_l2_cache_mask); set_cpus_unrelated(cpu, i, cpu_sibling_mask); } }

Contributors

PersonTokensPropCommitsCommitProp
Oliver O'Halloran4185.42%266.67%
Paul Mackerras714.58%133.33%
Total48100.00%3100.00%

#endif
static void add_cpu_to_masks(int cpu) { int first_thread = cpu_first_thread_sibling(cpu); int chipid = cpu_to_chip_id(cpu); int i; /* * This CPU will not be in the online mask yet so we need to manually * add it to it's own thread sibling mask. */ cpumask_set_cpu(cpu, cpu_sibling_mask(cpu)); for (i = first_thread; i < first_thread + threads_per_core; i++) if (cpu_online(i)) set_cpus_related(i, cpu, cpu_sibling_mask); /* * Copy the thread sibling mask into the cache sibling mask * and mark any CPUs that share an L2 with this CPU. */ for_each_cpu(i, cpu_sibling_mask(cpu)) set_cpus_related(cpu, i, cpu_l2_cache_mask); update_mask_by_l2(cpu, cpu_l2_cache_mask); /* * Copy the cache sibling mask into core sibling mask and mark * any CPUs on the same chip as this CPU. */ for_each_cpu(i, cpu_l2_cache_mask(cpu)) set_cpus_related(cpu, i, cpu_core_mask); if (chipid == -1) return; for_each_cpu(i, cpu_online_mask) if (cpu_to_chip_id(i) == chipid) set_cpus_related(cpu, i, cpu_core_mask); }

Contributors

PersonTokensPropCommitsCommitProp
Oliver O'Halloran12286.52%266.67%
Paul Mackerras1913.48%133.33%
Total141100.00%3100.00%

static bool shared_caches; /* Activate a secondary processor. */
void start_secondary(void *unused) { unsigned int cpu = smp_processor_id(); mmgrab(&init_mm); current->active_mm = &init_mm; smp_store_cpu_info(cpu); set_dec(tb_ticks_per_jiffy); preempt_disable(); cpu_callin_map[cpu] = 1; if (smp_ops->setup_cpu) smp_ops->setup_cpu(cpu); if (smp_ops->take_timebase) smp_ops->take_timebase(); secondary_cpu_time_init(); #ifdef CONFIG_PPC64 if (system_state == SYSTEM_RUNNING) vdso_data->processorCount++; vdso_getcpu_init(); #endif /* Update topology CPU masks */ add_cpu_to_masks(cpu); /* * Check for any shared caches. Note that this must be done on a * per-core basis because one core in the pair might be disabled. */ if (!cpumask_equal(cpu_l2_cache_mask(cpu), cpu_sibling_mask(cpu))) shared_caches = true; set_numa_node(numa_cpu_lookup_table[cpu]); set_numa_mem(local_memory_node(numa_cpu_lookup_table[cpu])); smp_wmb(); notify_cpu_starting(cpu); set_cpu_online(cpu, true); local_irq_enable(); cpu_startup_entry(CPUHP_AP_ONLINE_IDLE); BUG(); }

Contributors

PersonTokensPropCommitsCommitProp
Anton Blanchard5935.33%315.00%
Li Zhong3420.36%210.00%
Oliver O'Halloran2313.77%210.00%
Benjamin Herrenschmidt2011.98%210.00%
Michael Ellerman74.19%15.00%
Kumar Gala63.59%15.00%
Nathan T. Lynch42.40%15.00%
Thomas Gleixner42.40%210.00%
Tony Breeds31.80%15.00%
Andrew Morton31.80%15.00%
Vegard Nossum10.60%15.00%
Ingo Molnar10.60%15.00%
Paul Mackerras10.60%15.00%
Oleg Nesterov10.60%15.00%
Total167100.00%20100.00%


int setup_profiling_timer(unsigned int multiplier) { return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Anton Blanchard12100.00%1100.00%
Total12100.00%1100.00%

#ifdef CONFIG_SCHED_SMT /* cpumask of CPUs with asymetric SMT dependancy */
static int powerpc_smt_flags(void) { int flags = SD_SHARE_CPUCAPACITY | SD_SHARE_PKG_RESOURCES; if (cpu_has_feature(CPU_FTR_ASYM_SMT)) { printk_once(KERN_INFO "Enabling Asymmetric SMT scheduling\n"); flags |= SD_ASYM_PACKING; } return flags; }

Contributors

PersonTokensPropCommitsCommitProp
Vincent Guittot3697.30%150.00%
Nico Pitre12.70%150.00%
Total37100.00%2100.00%

#endif static struct sched_domain_topology_level powerpc_topology[] = { #ifdef CONFIG_SCHED_SMT { cpu_smt_mask, powerpc_smt_flags, SD_INIT_NAME(SMT) }, #endif { cpu_cpu_mask, SD_INIT_NAME(DIE) }, { NULL, }, }; /* * P9 has a slightly odd architecture where pairs of cores share an L2 cache. * This topology makes it *much* cheaper to migrate tasks between adjacent cores * since the migrated task remains cache hot. We want to take advantage of this * at the scheduler level so an extra topology level is required. */
static int powerpc_shared_cache_flags(void) { return SD_SHARE_PKG_RESOURCES; }

Contributors

PersonTokensPropCommitsCommitProp
Oliver O'Halloran11100.00%1100.00%
Total11100.00%1100.00%

/* * We can't just pass cpu_l2_cache_mask() directly because * returns a non-const pointer and the compiler barfs on that. */
static const struct cpumask *shared_cache_mask(int cpu) { return cpu_l2_cache_mask(cpu); }

Contributors

PersonTokensPropCommitsCommitProp
Oliver O'Halloran18100.00%1100.00%
Total18100.00%1100.00%

static struct sched_domain_topology_level power9_topology[] = { #ifdef CONFIG_SCHED_SMT { cpu_smt_mask, powerpc_smt_flags, SD_INIT_NAME(SMT) }, #endif { shared_cache_mask, powerpc_shared_cache_flags, SD_INIT_NAME(CACHE) }, { cpu_cpu_mask, SD_INIT_NAME(DIE) }, { NULL, }, };
void __init smp_cpus_done(unsigned int max_cpus) { /* * We are running pinned to the boot CPU, see rest_init(). */ if (smp_ops && smp_ops->setup_cpu) smp_ops->setup_cpu(boot_cpuid); if (smp_ops && smp_ops->bringup_done) smp_ops->bringup_done(); dump_numa_cpu_topology(); /* * If any CPU detects that it's sharing a cache with another CPU then * use the deeper topology that is aware of this sharing. */ if (shared_caches) { pr_info("Using shared cache scheduler topology\n"); set_sched_topology(power9_topology); } else { pr_info("Using standard scheduler topology\n"); set_sched_topology(powerpc_topology); } }

Contributors

PersonTokensPropCommitsCommitProp
Oliver O'Halloran2534.72%18.33%
Benjamin Herrenschmidt1723.61%216.67%
Anton Blanchard1419.44%433.33%
Kumar Gala45.56%18.33%
Michael Ellerman45.56%18.33%
Michael Neuling45.56%18.33%
Vincent Guittot22.78%18.33%
Andrew Morton22.78%18.33%
Total72100.00%12100.00%

#ifdef CONFIG_HOTPLUG_CPU
int __cpu_disable(void) { int cpu = smp_processor_id(); int err; if (!smp_ops->cpu_disable) return -ENOSYS; err = smp_ops->cpu_disable(); if (err) return err; /* Update sibling maps */ remove_cpu_from_masks(cpu); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Nathan T. Lynch2856.00%250.00%
Zwane Mwaikambo2142.00%125.00%
Oliver O'Halloran12.00%125.00%
Total50100.00%4100.00%


void __cpu_die(unsigned int cpu) { if (smp_ops->cpu_die) smp_ops->cpu_die(cpu); }

Contributors

PersonTokensPropCommitsCommitProp
Zwane Mwaikambo22100.00%1100.00%
Total22100.00%1100.00%


void cpu_die(void) { if (ppc_md.cpu_die) ppc_md.cpu_die(); /* If we return, we re-enter start_secondary */ start_secondary_resume(); }

Contributors

PersonTokensPropCommitsCommitProp
Milton D. Miller II1881.82%150.00%
Benjamin Herrenschmidt418.18%150.00%
Total22100.00%2100.00%

#endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Nicholas Piggin69718.99%74.58%
Oliver O'Halloran47512.94%42.61%
Anton Blanchard41711.36%2013.07%
Milton D. Miller II39210.68%74.58%
Benjamin Herrenschmidt3228.77%1610.46%
Paul Mackerras2005.45%117.19%
Nathan T. Lynch1855.04%42.61%
Zwane Mwaikambo1433.90%21.31%
Andrew Morton1333.62%95.88%
Vincent Guittot812.21%10.65%
Jens Axboe782.13%10.65%
Andy Fleming541.47%10.65%
Michael Ellerman541.47%85.23%
Suresh E. Warrier491.34%31.96%
Li Zhong431.17%21.31%
Chen-Hui Zhao421.14%31.96%
Srivatsa S. Bhat391.06%21.31%
Vaidyanathan Srinivasan371.01%10.65%
Nishanth Aravamudan320.87%21.31%
Thomas Gleixner250.68%63.92%
Becky Bruce230.63%10.65%
Will Schmidt160.44%10.65%
Olof Johansson150.41%10.65%
Kumar Gala140.38%10.65%
Satyam Sharma110.30%10.65%
Valentine Barshak90.25%10.65%
Santosh Sivaraj80.22%21.31%
Rusty Russell80.22%21.31%
Daniel Axtens60.16%21.31%
Mike Travis60.16%10.65%
Ingo Molnar50.14%31.96%
Mauricio Faria de Oliveira50.14%10.65%
Michael Neuling40.11%10.65%
Christian Krafft40.11%10.65%
David Howells30.08%10.65%
Tony Breeds30.08%10.65%
Peter Zijlstra30.08%10.65%
Kevin Hao30.08%10.65%
Al Viro30.08%10.65%
Avi Kivity20.05%10.65%
Gautham R. Shenoy20.05%10.65%
Darren Hart20.05%10.65%
Arnaldo Carvalho de Melo20.05%10.65%
Kay Sievers10.03%10.65%
Oleg Nesterov10.03%10.65%
David Gibson10.03%10.65%
Srivatsa Vaddagiri10.03%10.65%
Thiago Jung Bauermann10.03%10.65%
Tejun Heo10.03%10.65%
Jon Loeliger10.03%10.65%
Arun Sharma10.03%10.65%
Vegard Nossum10.03%10.65%
Hugh Dickins10.03%10.65%
Paul Gortmaker10.03%10.65%
Nico Pitre10.03%10.65%
Matthew Dobson10.03%10.65%
Motohiro Kosaki10.03%10.65%
Chen Gang S10.03%10.65%
Total3670100.00%153100.00%
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