596 строки
12 KiB
C
596 строки
12 KiB
C
/*
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* SMP support for ppc.
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*
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* Written by Cort Dougan (cort@cs.nmt.edu) borrowing a great
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* deal of code from the sparc and intel versions.
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*
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* Copyright (C) 1999 Cort Dougan <cort@cs.nmt.edu>
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*
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* PowerPC-64 Support added by Dave Engebretsen, Peter Bergner, and
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* Mike Corrigan {engebret|bergner|mikec}@us.ibm.com
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#undef DEBUG
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#include <linux/config.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/smp.h>
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#include <linux/interrupt.h>
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#include <linux/delay.h>
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#include <linux/init.h>
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#include <linux/spinlock.h>
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#include <linux/cache.h>
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#include <linux/err.h>
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#include <linux/sysdev.h>
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#include <linux/cpu.h>
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#include <linux/notifier.h>
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#include <linux/topology.h>
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#include <asm/ptrace.h>
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#include <asm/atomic.h>
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#include <asm/irq.h>
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#include <asm/page.h>
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#include <asm/pgtable.h>
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#include <asm/prom.h>
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#include <asm/smp.h>
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#include <asm/time.h>
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#include <asm/machdep.h>
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#include <asm/cputable.h>
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#include <asm/system.h>
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#include <asm/mpic.h>
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#include <asm/vdso_datapage.h>
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#ifdef CONFIG_PPC64
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#include <asm/paca.h>
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#endif
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#ifdef DEBUG
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#include <asm/udbg.h>
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#define DBG(fmt...) udbg_printf(fmt)
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#else
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#define DBG(fmt...)
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#endif
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int smp_hw_index[NR_CPUS];
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struct thread_info *secondary_ti;
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cpumask_t cpu_possible_map = CPU_MASK_NONE;
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cpumask_t cpu_online_map = CPU_MASK_NONE;
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cpumask_t cpu_sibling_map[NR_CPUS] = { [0 ... NR_CPUS-1] = CPU_MASK_NONE };
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EXPORT_SYMBOL(cpu_online_map);
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EXPORT_SYMBOL(cpu_possible_map);
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/* SMP operations for this machine */
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struct smp_ops_t *smp_ops;
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static volatile unsigned int cpu_callin_map[NR_CPUS];
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void smp_call_function_interrupt(void);
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int smt_enabled_at_boot = 1;
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static void (*crash_ipi_function_ptr)(struct pt_regs *) = NULL;
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#ifdef CONFIG_MPIC
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int __init smp_mpic_probe(void)
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{
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int nr_cpus;
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DBG("smp_mpic_probe()...\n");
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nr_cpus = cpus_weight(cpu_possible_map);
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DBG("nr_cpus: %d\n", nr_cpus);
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if (nr_cpus > 1)
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mpic_request_ipis();
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return nr_cpus;
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}
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void __devinit smp_mpic_setup_cpu(int cpu)
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{
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mpic_setup_this_cpu();
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}
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#endif /* CONFIG_MPIC */
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#ifdef CONFIG_PPC64
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void __devinit smp_generic_kick_cpu(int nr)
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{
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BUG_ON(nr < 0 || nr >= NR_CPUS);
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/*
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* The processor is currently spinning, waiting for the
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* cpu_start field to become non-zero After we set cpu_start,
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* the processor will continue on to secondary_start
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*/
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paca[nr].cpu_start = 1;
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smp_mb();
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}
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#endif
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void smp_message_recv(int msg, struct pt_regs *regs)
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{
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switch(msg) {
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case PPC_MSG_CALL_FUNCTION:
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smp_call_function_interrupt();
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break;
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case PPC_MSG_RESCHEDULE:
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/* XXX Do we have to do this? */
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set_need_resched();
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break;
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case PPC_MSG_DEBUGGER_BREAK:
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if (crash_ipi_function_ptr) {
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crash_ipi_function_ptr(regs);
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break;
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}
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#ifdef CONFIG_DEBUGGER
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debugger_ipi(regs);
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break;
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#endif /* CONFIG_DEBUGGER */
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/* FALLTHROUGH */
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default:
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printk("SMP %d: smp_message_recv(): unknown msg %d\n",
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smp_processor_id(), msg);
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break;
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}
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}
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void smp_send_reschedule(int cpu)
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{
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smp_ops->message_pass(cpu, PPC_MSG_RESCHEDULE);
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}
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#ifdef CONFIG_DEBUGGER
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void smp_send_debugger_break(int cpu)
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{
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smp_ops->message_pass(cpu, PPC_MSG_DEBUGGER_BREAK);
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}
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#endif
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#ifdef CONFIG_KEXEC
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void crash_send_ipi(void (*crash_ipi_callback)(struct pt_regs *))
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{
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crash_ipi_function_ptr = crash_ipi_callback;
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if (crash_ipi_callback) {
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mb();
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smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_DEBUGGER_BREAK);
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}
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}
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#endif
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static void stop_this_cpu(void *dummy)
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{
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local_irq_disable();
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while (1)
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;
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}
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void smp_send_stop(void)
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{
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smp_call_function(stop_this_cpu, NULL, 1, 0);
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}
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/*
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* Structure and data for smp_call_function(). This is designed to minimise
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* static memory requirements. It also looks cleaner.
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* Stolen from the i386 version.
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*/
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static __cacheline_aligned_in_smp DEFINE_SPINLOCK(call_lock);
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static struct call_data_struct {
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void (*func) (void *info);
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void *info;
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atomic_t started;
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atomic_t finished;
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int wait;
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} *call_data;
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/* delay of at least 8 seconds */
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#define SMP_CALL_TIMEOUT 8
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/*
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* This function sends a 'generic call function' IPI to all other CPUs
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* in the system.
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*
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* [SUMMARY] Run a function on all other CPUs.
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* <func> The function to run. This must be fast and non-blocking.
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* <info> An arbitrary pointer to pass to the function.
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* <nonatomic> currently unused.
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* <wait> If true, wait (atomically) until function has completed on other CPUs.
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* [RETURNS] 0 on success, else a negative status code. Does not return until
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* remote CPUs are nearly ready to execute <<func>> or are or have executed.
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*
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* You must not call this function with disabled interrupts or from a
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* hardware interrupt handler or from a bottom half handler.
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*/
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int smp_call_function (void (*func) (void *info), void *info, int nonatomic,
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int wait)
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{
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struct call_data_struct data;
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int ret = -1, cpus;
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u64 timeout;
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/* Can deadlock when called with interrupts disabled */
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WARN_ON(irqs_disabled());
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data.func = func;
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data.info = info;
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atomic_set(&data.started, 0);
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data.wait = wait;
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if (wait)
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atomic_set(&data.finished, 0);
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spin_lock(&call_lock);
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/* Must grab online cpu count with preempt disabled, otherwise
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* it can change. */
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cpus = num_online_cpus() - 1;
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if (!cpus) {
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ret = 0;
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goto out;
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}
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call_data = &data;
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smp_wmb();
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/* Send a message to all other CPUs and wait for them to respond */
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smp_ops->message_pass(MSG_ALL_BUT_SELF, PPC_MSG_CALL_FUNCTION);
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timeout = get_tb() + (u64) SMP_CALL_TIMEOUT * tb_ticks_per_sec;
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/* Wait for response */
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while (atomic_read(&data.started) != cpus) {
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HMT_low();
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if (get_tb() >= timeout) {
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printk("smp_call_function on cpu %d: other cpus not "
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"responding (%d)\n", smp_processor_id(),
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atomic_read(&data.started));
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debugger(NULL);
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goto out;
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}
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}
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if (wait) {
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while (atomic_read(&data.finished) != cpus) {
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HMT_low();
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if (get_tb() >= timeout) {
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printk("smp_call_function on cpu %d: other "
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"cpus not finishing (%d/%d)\n",
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smp_processor_id(),
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atomic_read(&data.finished),
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atomic_read(&data.started));
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debugger(NULL);
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goto out;
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}
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}
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}
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ret = 0;
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out:
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call_data = NULL;
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HMT_medium();
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spin_unlock(&call_lock);
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return ret;
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}
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EXPORT_SYMBOL(smp_call_function);
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void smp_call_function_interrupt(void)
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{
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void (*func) (void *info);
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void *info;
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int wait;
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/* call_data will be NULL if the sender timed out while
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* waiting on us to receive the call.
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*/
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if (!call_data)
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return;
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func = call_data->func;
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info = call_data->info;
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wait = call_data->wait;
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if (!wait)
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smp_mb__before_atomic_inc();
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/*
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* Notify initiating CPU that I've grabbed the data and am
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* about to execute the function
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*/
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atomic_inc(&call_data->started);
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/*
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* At this point the info structure may be out of scope unless wait==1
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*/
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(*func)(info);
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if (wait) {
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smp_mb__before_atomic_inc();
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atomic_inc(&call_data->finished);
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}
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}
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extern struct gettimeofday_struct do_gtod;
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struct thread_info *current_set[NR_CPUS];
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DECLARE_PER_CPU(unsigned int, pvr);
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static void __devinit smp_store_cpu_info(int id)
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{
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per_cpu(pvr, id) = mfspr(SPRN_PVR);
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}
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static void __init smp_create_idle(unsigned int cpu)
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{
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struct task_struct *p;
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/* create a process for the processor */
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p = fork_idle(cpu);
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if (IS_ERR(p))
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panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
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#ifdef CONFIG_PPC64
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paca[cpu].__current = p;
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#endif
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current_set[cpu] = task_thread_info(p);
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task_thread_info(p)->cpu = cpu;
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}
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void __init smp_prepare_cpus(unsigned int max_cpus)
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{
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unsigned int cpu;
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DBG("smp_prepare_cpus\n");
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/*
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* setup_cpu may need to be called on the boot cpu. We havent
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* spun any cpus up but lets be paranoid.
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*/
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BUG_ON(boot_cpuid != smp_processor_id());
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/* Fixup boot cpu */
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smp_store_cpu_info(boot_cpuid);
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cpu_callin_map[boot_cpuid] = 1;
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max_cpus = smp_ops->probe();
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smp_space_timers(max_cpus);
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for_each_cpu(cpu)
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if (cpu != boot_cpuid)
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smp_create_idle(cpu);
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}
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void __devinit smp_prepare_boot_cpu(void)
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{
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BUG_ON(smp_processor_id() != boot_cpuid);
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cpu_set(boot_cpuid, cpu_online_map);
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#ifdef CONFIG_PPC64
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paca[boot_cpuid].__current = current;
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#endif
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current_set[boot_cpuid] = task_thread_info(current);
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}
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#ifdef CONFIG_HOTPLUG_CPU
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/* State of each CPU during hotplug phases */
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DEFINE_PER_CPU(int, cpu_state) = { 0 };
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int generic_cpu_disable(void)
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{
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unsigned int cpu = smp_processor_id();
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if (cpu == boot_cpuid)
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return -EBUSY;
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cpu_clear(cpu, cpu_online_map);
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#ifdef CONFIG_PPC64
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vdso_data->processorCount--;
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fixup_irqs(cpu_online_map);
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#endif
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return 0;
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}
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int generic_cpu_enable(unsigned int cpu)
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{
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/* Do the normal bootup if we haven't
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* already bootstrapped. */
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if (system_state != SYSTEM_RUNNING)
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return -ENOSYS;
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/* get the target out of it's holding state */
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per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
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smp_wmb();
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while (!cpu_online(cpu))
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cpu_relax();
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#ifdef CONFIG_PPC64
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fixup_irqs(cpu_online_map);
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/* counter the irq disable in fixup_irqs */
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local_irq_enable();
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#endif
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return 0;
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}
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void generic_cpu_die(unsigned int cpu)
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{
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int i;
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for (i = 0; i < 100; i++) {
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smp_rmb();
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if (per_cpu(cpu_state, cpu) == CPU_DEAD)
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return;
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msleep(100);
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}
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printk(KERN_ERR "CPU%d didn't die...\n", cpu);
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}
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void generic_mach_cpu_die(void)
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{
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unsigned int cpu;
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local_irq_disable();
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cpu = smp_processor_id();
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printk(KERN_DEBUG "CPU%d offline\n", cpu);
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__get_cpu_var(cpu_state) = CPU_DEAD;
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smp_wmb();
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while (__get_cpu_var(cpu_state) != CPU_UP_PREPARE)
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cpu_relax();
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#ifdef CONFIG_PPC64
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flush_tlb_pending();
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#endif
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cpu_set(cpu, cpu_online_map);
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local_irq_enable();
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}
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#endif
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static int __devinit cpu_enable(unsigned int cpu)
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{
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if (smp_ops->cpu_enable)
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return smp_ops->cpu_enable(cpu);
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return -ENOSYS;
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}
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int __devinit __cpu_up(unsigned int cpu)
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{
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int c;
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secondary_ti = current_set[cpu];
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if (!cpu_enable(cpu))
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return 0;
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if (smp_ops->cpu_bootable && !smp_ops->cpu_bootable(cpu))
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return -EINVAL;
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/* Make sure callin-map entry is 0 (can be leftover a CPU
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* hotplug
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*/
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cpu_callin_map[cpu] = 0;
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/* The information for processor bringup must
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* be written out to main store before we release
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* the processor.
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*/
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smp_mb();
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/* wake up cpus */
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DBG("smp: kicking cpu %d\n", cpu);
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smp_ops->kick_cpu(cpu);
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/*
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* wait to see if the cpu made a callin (is actually up).
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* use this value that I found through experimentation.
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* -- Cort
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*/
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if (system_state < SYSTEM_RUNNING)
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for (c = 5000; c && !cpu_callin_map[cpu]; c--)
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udelay(100);
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#ifdef CONFIG_HOTPLUG_CPU
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else
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/*
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* CPUs can take much longer to come up in the
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* hotplug case. Wait five seconds.
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*/
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for (c = 25; c && !cpu_callin_map[cpu]; c--) {
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msleep(200);
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}
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#endif
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if (!cpu_callin_map[cpu]) {
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printk("Processor %u is stuck.\n", cpu);
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return -ENOENT;
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}
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printk("Processor %u found.\n", cpu);
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if (smp_ops->give_timebase)
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smp_ops->give_timebase();
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/* Wait until cpu puts itself in the online map */
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while (!cpu_online(cpu))
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cpu_relax();
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return 0;
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}
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/* Activate a secondary processor. */
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int __devinit start_secondary(void *unused)
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{
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unsigned int cpu = smp_processor_id();
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atomic_inc(&init_mm.mm_count);
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current->active_mm = &init_mm;
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smp_store_cpu_info(cpu);
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set_dec(tb_ticks_per_jiffy);
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preempt_disable();
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cpu_callin_map[cpu] = 1;
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smp_ops->setup_cpu(cpu);
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if (smp_ops->take_timebase)
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smp_ops->take_timebase();
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if (system_state > SYSTEM_BOOTING)
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snapshot_timebase();
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spin_lock(&call_lock);
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cpu_set(cpu, cpu_online_map);
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spin_unlock(&call_lock);
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local_irq_enable();
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cpu_idle();
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return 0;
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}
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int setup_profiling_timer(unsigned int multiplier)
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{
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return 0;
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}
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void __init smp_cpus_done(unsigned int max_cpus)
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{
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cpumask_t old_mask;
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|
|
|
/* We want the setup_cpu() here to be called from CPU 0, but our
|
|
* init thread may have been "borrowed" by another CPU in the meantime
|
|
* se we pin us down to CPU 0 for a short while
|
|
*/
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|
old_mask = current->cpus_allowed;
|
|
set_cpus_allowed(current, cpumask_of_cpu(boot_cpuid));
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|
|
|
smp_ops->setup_cpu(boot_cpuid);
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|
|
|
set_cpus_allowed(current, old_mask);
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|
|
|
snapshot_timebases();
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|
|
|
dump_numa_cpu_topology();
|
|
}
|
|
|
|
#ifdef CONFIG_HOTPLUG_CPU
|
|
int __cpu_disable(void)
|
|
{
|
|
if (smp_ops->cpu_disable)
|
|
return smp_ops->cpu_disable();
|
|
|
|
return -ENOSYS;
|
|
}
|
|
|
|
void __cpu_die(unsigned int cpu)
|
|
{
|
|
if (smp_ops->cpu_die)
|
|
smp_ops->cpu_die(cpu);
|
|
}
|
|
#endif
|