Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 396 insertions, 0 deletions

diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c
new file mode 100644
index 000000000000..ecc8c3332408
--- /dev/null
+++ b/arch/arm/kernel/smp.c
@@ -0,0 +1,396 @@
+/*
+ *  linux/arch/arm/kernel/smp.c
+ *
+ *  Copyright (C) 2002 ARM Limited, All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/config.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/cache.h>
+#include <linux/profile.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/cpu.h>
+#include <linux/smp.h>
+#include <linux/seq_file.h>
+
+#include <asm/atomic.h>
+#include <asm/cacheflush.h>
+#include <asm/cpu.h>
+#include <asm/processor.h>
+#include <asm/tlbflush.h>
+#include <asm/ptrace.h>
+
+/*
+ * bitmask of present and online CPUs.
+ * The present bitmask indicates that the CPU is physically present.
+ * The online bitmask indicates that the CPU is up and running.
+ */
+cpumask_t cpu_present_mask;
+cpumask_t cpu_online_map;
+
+/*
+ * structures for inter-processor calls
+ * - A collection of single bit ipi messages.
+ */
+struct ipi_data {
+        spinlock_t lock;
+        unsigned long ipi_count;
+        unsigned long bits;
+};
+
+static DEFINE_PER_CPU(struct ipi_data, ipi_data) = {
+        .lock   = SPIN_LOCK_UNLOCKED,
+};
+
+enum ipi_msg_type {
+        IPI_TIMER,
+        IPI_RESCHEDULE,
+        IPI_CALL_FUNC,
+        IPI_CPU_STOP,
+};
+
+struct smp_call_struct {
+        void (*func)(void *info);
+        void *info;
+        int wait;
+        cpumask_t pending;
+        cpumask_t unfinished;
+};
+
+static struct smp_call_struct * volatile smp_call_function_data;
+static DEFINE_SPINLOCK(smp_call_function_lock);
+
+int __init __cpu_up(unsigned int cpu)
+{
+        struct task_struct *idle;
+        int ret;
+
+        /*
+         * Spawn a new process manually.  Grab a pointer to
+         * its task struct so we can mess with it
+         */
+        idle = fork_idle(cpu);
+        if (IS_ERR(idle)) {
+                printk(KERN_ERR "CPU%u: fork() failed\n", cpu);
+                return PTR_ERR(idle);
+        }
+
+        /*
+         * Now bring the CPU into our world.
+         */
+        ret = boot_secondary(cpu, idle);
+        if (ret) {
+                printk(KERN_CRIT "cpu_up: processor %d failed to boot\n", cpu);
+                /*
+                 * FIXME: We need to clean up the new idle thread. --rmk
+                 */
+        }
+
+        return ret;
+}
+
+/*
+ * Called by both boot and secondaries to move global data into
+ * per-processor storage.
+ */
+void __init smp_store_cpu_info(unsigned int cpuid)
+{
+        struct cpuinfo_arm *cpu_info = &per_cpu(cpu_data, cpuid);
+
+        cpu_info->loops_per_jiffy = loops_per_jiffy;
+}
+
+void __init smp_cpus_done(unsigned int max_cpus)
+{
+        int cpu;
+        unsigned long bogosum = 0;
+
+        for_each_online_cpu(cpu)
+                bogosum += per_cpu(cpu_data, cpu).loops_per_jiffy;
+
+        printk(KERN_INFO "SMP: Total of %d processors activated "
+               "(%lu.%02lu BogoMIPS).\n",
+               num_online_cpus(),
+               bogosum / (500000/HZ),
+               (bogosum / (5000/HZ)) % 100);
+}
+
+void __init smp_prepare_boot_cpu(void)
+{
+        unsigned int cpu = smp_processor_id();
+
+        cpu_set(cpu, cpu_present_mask);
+        cpu_set(cpu, cpu_online_map);
+}
+
+static void send_ipi_message(cpumask_t callmap, enum ipi_msg_type msg)
+{
+        unsigned long flags;
+        unsigned int cpu;
+
+        local_irq_save(flags);
+
+        for_each_cpu_mask(cpu, callmap) {
+                struct ipi_data *ipi = &per_cpu(ipi_data, cpu);
+
+                spin_lock(&ipi->lock);
+                ipi->bits |= 1 << msg;
+                spin_unlock(&ipi->lock);
+        }
+
+        /*
+         * Call the platform specific cross-CPU call function.
+         */
+        smp_cross_call(callmap);
+
+        local_irq_restore(flags);
+}
+
+/*
+ * You must not call this function with disabled interrupts, from a
+ * hardware interrupt handler, nor from a bottom half handler.
+ */
+int smp_call_function_on_cpu(void (*func)(void *info), void *info, int retry,
+                             int wait, cpumask_t callmap)
+{
+        struct smp_call_struct data;
+        unsigned long timeout;
+        int ret = 0;
+
+        data.func = func;
+        data.info = info;
+        data.wait = wait;
+
+        cpu_clear(smp_processor_id(), callmap);
+        if (cpus_empty(callmap))
+                goto out;
+
+        data.pending = callmap;
+        if (wait)
+                data.unfinished = callmap;
+
+        /*
+         * try to get the mutex on smp_call_function_data
+         */
+        spin_lock(&smp_call_function_lock);
+        smp_call_function_data = &data;
+
+        send_ipi_message(callmap, IPI_CALL_FUNC);
+
+        timeout = jiffies + HZ;
+        while (!cpus_empty(data.pending) && time_before(jiffies, timeout))
+                barrier();
+
+        /*
+         * did we time out?
+         */
+        if (!cpus_empty(data.pending)) {
+                /*
+                 * this may be causing our panic - report it
+                 */
+                printk(KERN_CRIT
+                       "CPU%u: smp_call_function timeout for %p(%p)\n"
+                       "      callmap %lx pending %lx, %swait\n",
+                       smp_processor_id(), func, info, callmap, data.pending,
+                       wait ? "" : "no ");
+
+                /*
+                 * TRACE
+                 */
+                timeout = jiffies + (5 * HZ);
+                while (!cpus_empty(data.pending) && time_before(jiffies, timeout))
+                        barrier();
+
+                if (cpus_empty(data.pending))
+                        printk(KERN_CRIT "     RESOLVED\n");
+                else
+                        printk(KERN_CRIT "     STILL STUCK\n");
+        }
+
+        /*
+         * whatever happened, we're done with the data, so release it
+         */
+        smp_call_function_data = NULL;
+        spin_unlock(&smp_call_function_lock);
+
+        if (!cpus_empty(data.pending)) {
+                ret = -ETIMEDOUT;
+                goto out;
+        }
+
+        if (wait)
+                while (!cpus_empty(data.unfinished))
+                        barrier();
+ out:
+
+        return 0;
+}
+
+int smp_call_function(void (*func)(void *info), void *info, int retry,
+                      int wait)
+{
+        return smp_call_function_on_cpu(func, info, retry, wait,
+                                        cpu_online_map);
+}
+
+void show_ipi_list(struct seq_file *p)
+{
+        unsigned int cpu;
+
+        seq_puts(p, "IPI:");
+
+        for_each_online_cpu(cpu)
+                seq_printf(p, " %10lu", per_cpu(ipi_data, cpu).ipi_count);
+
+        seq_putc(p, '\n');
+}
+
+static void ipi_timer(struct pt_regs *regs)
+{
+        int user = user_mode(regs);
+
+        irq_enter();
+        profile_tick(CPU_PROFILING, regs);
+        update_process_times(user);
+        irq_exit();
+}
+
+/*
+ * ipi_call_function - handle IPI from smp_call_function()
+ *
+ * Note that we copy data out of the cross-call structure and then
+ * let the caller know that we're here and have done with their data
+ */
+static void ipi_call_function(unsigned int cpu)
+{
+        struct smp_call_struct *data = smp_call_function_data;
+        void (*func)(void *info) = data->func;
+        void *info = data->info;
+        int wait = data->wait;
+
+        cpu_clear(cpu, data->pending);
+
+        func(info);
+
+        if (wait)
+                cpu_clear(cpu, data->unfinished);
+}
+
+static DEFINE_SPINLOCK(stop_lock);
+
+/*
+ * ipi_cpu_stop - handle IPI from smp_send_stop()
+ */
+static void ipi_cpu_stop(unsigned int cpu)
+{
+        spin_lock(&stop_lock);
+        printk(KERN_CRIT "CPU%u: stopping\n", cpu);
+        dump_stack();
+        spin_unlock(&stop_lock);
+
+        cpu_clear(cpu, cpu_online_map);
+
+        local_fiq_disable();
+        local_irq_disable();
+
+        while (1)
+                cpu_relax();
+}
+
+/*
+ * Main handler for inter-processor interrupts
+ *
+ * For ARM, the ipimask now only identifies a single
+ * category of IPI (Bit 1 IPIs have been replaced by a
+ * different mechanism):
+ *
+ *  Bit 0 - Inter-processor function call
+ */
+void do_IPI(struct pt_regs *regs)
+{
+        unsigned int cpu = smp_processor_id();
+        struct ipi_data *ipi = &per_cpu(ipi_data, cpu);
+
+        ipi->ipi_count++;
+
+        for (;;) {
+                unsigned long msgs;
+
+                spin_lock(&ipi->lock);
+                msgs = ipi->bits;
+                ipi->bits = 0;
+                spin_unlock(&ipi->lock);
+
+                if (!msgs)
+                        break;
+
+                do {
+                        unsigned nextmsg;
+
+                        nextmsg = msgs & -msgs;
+                        msgs &= ~nextmsg;
+                        nextmsg = ffz(~nextmsg);
+
+                        switch (nextmsg) {
+                        case IPI_TIMER:
+                                ipi_timer(regs);
+                                break;
+
+                        case IPI_RESCHEDULE:
+                                /*
+                                 * nothing more to do - eveything is
+                                 * done on the interrupt return path
+                                 */
+                                break;
+
+                        case IPI_CALL_FUNC:
+                                ipi_call_function(cpu);
+                                break;
+
+                        case IPI_CPU_STOP:
+                                ipi_cpu_stop(cpu);
+                                break;
+
+                        default:
+                                printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%x\n",
+                                       cpu, nextmsg);
+                                break;
+                        }
+                } while (msgs);
+        }
+}
+
+void smp_send_reschedule(int cpu)
+{
+        send_ipi_message(cpumask_of_cpu(cpu), IPI_RESCHEDULE);
+}
+
+void smp_send_timer(void)
+{
+        cpumask_t mask = cpu_online_map;
+        cpu_clear(smp_processor_id(), mask);
+        send_ipi_message(mask, IPI_TIMER);
+}
+
+void smp_send_stop(void)
+{
+        cpumask_t mask = cpu_online_map;
+        cpu_clear(smp_processor_id(), mask);
+        send_ipi_message(mask, IPI_CPU_STOP);
+}
+
+/*
+ * not supported here
+ */
+int __init setup_profiling_timer(unsigned int multiplier)
+{
+        return -EINVAL;
+}