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, 723 insertions, 0 deletions

diff --git a/arch/parisc/kernel/smp.c b/arch/parisc/kernel/smp.c
new file mode 100644
index 0000000..bcc7e83
--- /dev/null
+++ b/arch/parisc/kernel/smp.c
@@ -0,0 +1,723 @@
+/*
+** SMP Support
+**
+** Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+** Copyright (C) 1999 David Mosberger-Tang <davidm@hpl.hp.com>
+** Copyright (C) 2001,2004 Grant Grundler <grundler@parisc-linux.org>
+** 
+** Lots of stuff stolen from arch/alpha/kernel/smp.c
+** ...and then parisc stole from arch/ia64/kernel/smp.c. Thanks David! :^)
+**
+** Thanks to John Curry and Ullas Ponnadi. I learned alot from their work.
+** -grant (1/12/2001)
+**
+**	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 ENTRY_SYS_CPUS	/* syscall support for iCOD-like functionality */
+
+#include <linux/autoconf.h>
+
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/kernel_stat.h>
+#include <linux/mm.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+
+#include <asm/system.h>
+#include <asm/atomic.h>
+#include <asm/current.h>
+#include <asm/delay.h>
+#include <asm/pgalloc.h>	/* for flush_tlb_all() proto/macro */
+
+#include <asm/io.h>
+#include <asm/irq.h>		/* for CPU_IRQ_REGION and friends */
+#include <asm/mmu_context.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/unistd.h>
+#include <asm/cacheflush.h>
+
+#define kDEBUG 0
+
+DEFINE_SPINLOCK(smp_lock);
+
+volatile struct task_struct *smp_init_current_idle_task;
+
+static volatile int cpu_now_booting = 0;	/* track which CPU is booting */
+
+static int parisc_max_cpus = 1;
+
+/* online cpus are ones that we've managed to bring up completely
+ * possible cpus are all valid cpu 
+ * present cpus are all detected cpu
+ *
+ * On startup we bring up the "possible" cpus. Since we discover
+ * CPUs later, we add them as hotplug, so the possible cpu mask is
+ * empty in the beginning.
+ */
+
+cpumask_t cpu_online_map = CPU_MASK_NONE;	/* Bitmap of online CPUs */
+cpumask_t cpu_possible_map = CPU_MASK_ALL;	/* Bitmap of Present CPUs */
+
+EXPORT_SYMBOL(cpu_online_map);
+EXPORT_SYMBOL(cpu_possible_map);
+
+
+struct smp_call_struct {
+	void (*func) (void *info);
+	void *info;
+	long wait;
+	atomic_t unstarted_count;
+	atomic_t unfinished_count;
+};
+static volatile struct smp_call_struct *smp_call_function_data;
+
+enum ipi_message_type {
+	IPI_NOP=0,
+	IPI_RESCHEDULE=1,
+	IPI_CALL_FUNC,
+	IPI_CPU_START,
+	IPI_CPU_STOP,
+	IPI_CPU_TEST
+};
+
+
+/********** SMP inter processor interrupt and communication routines */
+
+#undef PER_CPU_IRQ_REGION
+#ifdef PER_CPU_IRQ_REGION
+/* XXX REVISIT Ignore for now.
+**    *May* need this "hook" to register IPI handler
+**    once we have perCPU ExtIntr switch tables.
+*/
+static void
+ipi_init(int cpuid)
+{
+
+	/* If CPU is present ... */
+#ifdef ENTRY_SYS_CPUS
+	/* *and* running (not stopped) ... */
+#error iCOD support wants state checked here.
+#endif
+
+#error verify IRQ_OFFSET(IPI_IRQ) is ipi_interrupt() in new IRQ region
+
+	if(cpu_online(cpuid) )
+	{
+		switch_to_idle_task(current);
+	}
+
+	return;
+}
+#endif
+
+
+/*
+** Yoink this CPU from the runnable list... 
+**
+*/
+static void
+halt_processor(void) 
+{
+#ifdef ENTRY_SYS_CPUS
+#error halt_processor() needs rework
+/*
+** o migrate I/O interrupts off this CPU.
+** o leave IPI enabled - __cli() will disable IPI.
+** o leave CPU in online map - just change the state
+*/
+	cpu_data[this_cpu].state = STATE_STOPPED;
+	mark_bh(IPI_BH);
+#else
+	/* REVISIT : redirect I/O Interrupts to another CPU? */
+	/* REVISIT : does PM *know* this CPU isn't available? */
+	cpu_clear(smp_processor_id(), cpu_online_map);
+	local_irq_disable();
+	for (;;)
+		;
+#endif
+}
+
+
+irqreturn_t
+ipi_interrupt(int irq, void *dev_id, struct pt_regs *regs) 
+{
+	int this_cpu = smp_processor_id();
+	struct cpuinfo_parisc *p = &cpu_data[this_cpu];
+	unsigned long ops;
+	unsigned long flags;
+
+	/* Count this now; we may make a call that never returns. */
+	p->ipi_count++;
+
+	mb();	/* Order interrupt and bit testing. */
+
+	for (;;) {
+		spin_lock_irqsave(&(p->lock),flags);
+		ops = p->pending_ipi;
+		p->pending_ipi = 0;
+		spin_unlock_irqrestore(&(p->lock),flags);
+
+		mb(); /* Order bit clearing and data access. */
+
+		if (!ops)
+		    break;
+
+		while (ops) {
+			unsigned long which = ffz(~ops);
+
+			switch (which) {
+			case IPI_RESCHEDULE:
+#if (kDEBUG>=100)
+				printk(KERN_DEBUG "CPU%d IPI_RESCHEDULE\n",this_cpu);
+#endif /* kDEBUG */
+				ops &= ~(1 << IPI_RESCHEDULE);
+				/*
+				 * Reschedule callback.  Everything to be
+				 * done is done by the interrupt return path.
+				 */
+				break;
+
+			case IPI_CALL_FUNC:
+#if (kDEBUG>=100)
+				printk(KERN_DEBUG "CPU%d IPI_CALL_FUNC\n",this_cpu);
+#endif /* kDEBUG */
+				ops &= ~(1 << IPI_CALL_FUNC);
+				{
+					volatile struct smp_call_struct *data;
+					void (*func)(void *info);
+					void *info;
+					int wait;
+
+					data = smp_call_function_data;
+					func = data->func;
+					info = data->info;
+					wait = data->wait;
+
+					mb();
+					atomic_dec ((atomic_t *)&data->unstarted_count);
+
+					/* At this point, *data can't
+					 * be relied upon.
+					 */
+
+					(*func)(info);
+
+					/* Notify the sending CPU that the
+					 * task is done.
+					 */
+					mb();
+					if (wait)
+						atomic_dec ((atomic_t *)&data->unfinished_count);
+				}
+				break;
+
+			case IPI_CPU_START:
+#if (kDEBUG>=100)
+				printk(KERN_DEBUG "CPU%d IPI_CPU_START\n",this_cpu);
+#endif /* kDEBUG */
+				ops &= ~(1 << IPI_CPU_START);
+#ifdef ENTRY_SYS_CPUS
+				p->state = STATE_RUNNING;
+#endif
+				break;
+
+			case IPI_CPU_STOP:
+#if (kDEBUG>=100)
+				printk(KERN_DEBUG "CPU%d IPI_CPU_STOP\n",this_cpu);
+#endif /* kDEBUG */
+				ops &= ~(1 << IPI_CPU_STOP);
+#ifdef ENTRY_SYS_CPUS
+#else
+				halt_processor();
+#endif
+				break;
+
+			case IPI_CPU_TEST:
+#if (kDEBUG>=100)
+				printk(KERN_DEBUG "CPU%d is alive!\n",this_cpu);
+#endif /* kDEBUG */
+				ops &= ~(1 << IPI_CPU_TEST);
+				break;
+
+			default:
+				printk(KERN_CRIT "Unknown IPI num on CPU%d: %lu\n",
+					this_cpu, which);
+				ops &= ~(1 << which);
+				return IRQ_NONE;
+			} /* Switch */
+		} /* while (ops) */
+	}
+	return IRQ_HANDLED;
+}
+
+
+static inline void
+ipi_send(int cpu, enum ipi_message_type op)
+{
+	struct cpuinfo_parisc *p = &cpu_data[cpu];
+	unsigned long flags;
+
+	spin_lock_irqsave(&(p->lock),flags);
+	p->pending_ipi |= 1 << op;
+	gsc_writel(IPI_IRQ - CPU_IRQ_BASE, cpu_data[cpu].hpa);
+	spin_unlock_irqrestore(&(p->lock),flags);
+}
+
+
+static inline void
+send_IPI_single(int dest_cpu, enum ipi_message_type op)
+{
+	if (dest_cpu == NO_PROC_ID) {
+		BUG();
+		return;
+	}
+
+	ipi_send(dest_cpu, op);
+}
+
+static inline void
+send_IPI_allbutself(enum ipi_message_type op)
+{
+	int i;
+	
+	for (i = 0; i < NR_CPUS; i++) {
+		if (cpu_online(i) && i != smp_processor_id())
+			send_IPI_single(i, op);
+	}
+}
+
+
+inline void 
+smp_send_stop(void)	{ send_IPI_allbutself(IPI_CPU_STOP); }
+
+static inline void
+smp_send_start(void)	{ send_IPI_allbutself(IPI_CPU_START); }
+
+void 
+smp_send_reschedule(int cpu) { send_IPI_single(cpu, IPI_RESCHEDULE); }
+
+
+/**
+ * Run a function on all other CPUs.
+ *  <func>	The function to run. This must be fast and non-blocking.
+ *  <info>	An arbitrary pointer to pass to the function.
+ *  <retry>	If true, keep retrying until ready.
+ *  <wait>	If true, wait until function has completed on other CPUs.
+ *  [RETURNS]   0 on success, else a negative status code.
+ *
+ * Does not return until remote CPUs are nearly ready to execute <func>
+ * or have executed.
+ */
+
+int
+smp_call_function (void (*func) (void *info), void *info, int retry, int wait)
+{
+	struct smp_call_struct data;
+	unsigned long timeout;
+	static DEFINE_SPINLOCK(lock);
+	int retries = 0;
+
+	if (num_online_cpus() < 2)
+		return 0;
+
+	/* Can deadlock when called with interrupts disabled */
+	WARN_ON(irqs_disabled());
+	
+	data.func = func;
+	data.info = info;
+	data.wait = wait;
+	atomic_set(&data.unstarted_count, num_online_cpus() - 1);
+	atomic_set(&data.unfinished_count, num_online_cpus() - 1);
+
+	if (retry) {
+		spin_lock (&lock);
+		while (smp_call_function_data != 0)
+			barrier();
+	}
+	else {
+		spin_lock (&lock);
+		if (smp_call_function_data) {
+			spin_unlock (&lock);
+			return -EBUSY;
+		}
+	}
+
+	smp_call_function_data = &data;
+	spin_unlock (&lock);
+	
+	/*  Send a message to all other CPUs and wait for them to respond  */
+	send_IPI_allbutself(IPI_CALL_FUNC);
+
+ retry:
+	/*  Wait for response  */
+	timeout = jiffies + HZ;
+	while ( (atomic_read (&data.unstarted_count) > 0) &&
+		time_before (jiffies, timeout) )
+		barrier ();
+
+	if (atomic_read (&data.unstarted_count) > 0) {
+		printk(KERN_CRIT "SMP CALL FUNCTION TIMED OUT! (cpu=%d), try %d\n",
+		      smp_processor_id(), ++retries);
+		goto retry;
+	}
+	/* We either got one or timed out. Release the lock */
+
+	mb();
+	smp_call_function_data = NULL;
+
+	while (wait && atomic_read (&data.unfinished_count) > 0)
+			barrier ();
+
+	return 0;
+}
+
+EXPORT_SYMBOL(smp_call_function);
+
+/*
+ * Flush all other CPU's tlb and then mine.  Do this with on_each_cpu()
+ * as we want to ensure all TLB's flushed before proceeding.
+ */
+
+extern void flush_tlb_all_local(void);
+
+void
+smp_flush_tlb_all(void)
+{
+	on_each_cpu((void (*)(void *))flush_tlb_all_local, NULL, 1, 1);
+}
+
+
+void 
+smp_do_timer(struct pt_regs *regs)
+{
+	int cpu = smp_processor_id();
+	struct cpuinfo_parisc *data = &cpu_data[cpu];
+
+        if (!--data->prof_counter) {
+		data->prof_counter = data->prof_multiplier;
+		update_process_times(user_mode(regs));
+	}
+}
+
+/*
+ * Called by secondaries to update state and initialize CPU registers.
+ */
+static void __init
+smp_cpu_init(int cpunum)
+{
+	extern int init_per_cpu(int);  /* arch/parisc/kernel/setup.c */
+	extern void init_IRQ(void);    /* arch/parisc/kernel/irq.c */
+
+	/* Set modes and Enable floating point coprocessor */
+	(void) init_per_cpu(cpunum);
+
+	disable_sr_hashing();
+
+	mb();
+
+	/* Well, support 2.4 linux scheme as well. */
+	if (cpu_test_and_set(cpunum, cpu_online_map))
+	{
+		extern void machine_halt(void); /* arch/parisc.../process.c */
+
+		printk(KERN_CRIT "CPU#%d already initialized!\n", cpunum);
+		machine_halt();
+	}  
+
+	/* Initialise the idle task for this CPU */
+	atomic_inc(&init_mm.mm_count);
+	current->active_mm = &init_mm;
+	if(current->mm)
+		BUG();
+	enter_lazy_tlb(&init_mm, current);
+
+	init_IRQ();   /* make sure no IRQ's are enabled or pending */
+}
+
+
+/*
+ * Slaves start using C here. Indirectly called from smp_slave_stext.
+ * Do what start_kernel() and main() do for boot strap processor (aka monarch)
+ */
+void __init smp_callin(void)
+{
+	int slave_id = cpu_now_booting;
+#if 0
+	void *istack;
+#endif
+
+	smp_cpu_init(slave_id);
+
+#if 0	/* NOT WORKING YET - see entry.S */
+	istack = (void *)__get_free_pages(GFP_KERNEL,ISTACK_ORDER);
+	if (istack == NULL) {
+	    printk(KERN_CRIT "Failed to allocate interrupt stack for cpu %d\n",slave_id);
+	    BUG();
+	}
+	mtctl(istack,31);
+#endif
+
+	flush_cache_all_local(); /* start with known state */
+	flush_tlb_all_local();
+
+	local_irq_enable();  /* Interrupts have been off until now */
+
+	cpu_idle();      /* Wait for timer to schedule some work */
+
+	/* NOTREACHED */
+	panic("smp_callin() AAAAaaaaahhhh....\n");
+}
+
+/*
+ * Bring one cpu online.
+ */
+int __init smp_boot_one_cpu(int cpuid)
+{
+	struct task_struct *idle;
+	long timeout;
+
+	/* 
+	 * Create an idle task for this CPU.  Note the address wed* give 
+	 * to kernel_thread is irrelevant -- it's going to start
+	 * where OS_BOOT_RENDEVZ vector in SAL says to start.  But
+	 * this gets all the other task-y sort of data structures set
+	 * up like we wish.   We need to pull the just created idle task 
+	 * off the run queue and stuff it into the init_tasks[] array.  
+	 * Sheesh . . .
+	 */
+
+	idle = fork_idle(cpuid);
+	if (IS_ERR(idle))
+		panic("SMP: fork failed for CPU:%d", cpuid);
+
+	idle->thread_info->cpu = cpuid;
+
+	/* Let _start know what logical CPU we're booting
+	** (offset into init_tasks[],cpu_data[])
+	*/
+	cpu_now_booting = cpuid;
+
+	/* 
+	** boot strap code needs to know the task address since
+	** it also contains the process stack.
+	*/
+	smp_init_current_idle_task = idle ;
+	mb();
+
+	printk("Releasing cpu %d now, hpa=%lx\n", cpuid, cpu_data[cpuid].hpa);
+
+	/*
+	** This gets PDC to release the CPU from a very tight loop.
+	**
+	** From the PA-RISC 2.0 Firmware Architecture Reference Specification:
+	** "The MEM_RENDEZ vector specifies the location of OS_RENDEZ which 
+	** is executed after receiving the rendezvous signal (an interrupt to 
+	** EIR{0}). MEM_RENDEZ is valid only when it is nonzero and the 
+	** contents of memory are valid."
+	*/
+	gsc_writel(TIMER_IRQ - CPU_IRQ_BASE, cpu_data[cpuid].hpa);
+	mb();
+
+	/* 
+	 * OK, wait a bit for that CPU to finish staggering about. 
+	 * Slave will set a bit when it reaches smp_cpu_init().
+	 * Once the "monarch CPU" sees the bit change, it can move on.
+	 */
+	for (timeout = 0; timeout < 10000; timeout++) {
+		if(cpu_online(cpuid)) {
+			/* Which implies Slave has started up */
+			cpu_now_booting = 0;
+			smp_init_current_idle_task = NULL;
+			goto alive ;
+		}
+		udelay(100);
+		barrier();
+	}
+
+	put_task_struct(idle);
+	idle = NULL;
+
+	printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
+	return -1;
+
+alive:
+	/* Remember the Slave data */
+#if (kDEBUG>=100)
+	printk(KERN_DEBUG "SMP: CPU:%d came alive after %ld _us\n",
+		cpuid, timeout * 100);
+#endif /* kDEBUG */
+#ifdef ENTRY_SYS_CPUS
+	cpu_data[cpuid].state = STATE_RUNNING;
+#endif
+	return 0;
+}
+
+void __devinit smp_prepare_boot_cpu(void)
+{
+	int bootstrap_processor=cpu_data[0].cpuid;	/* CPU ID of BSP */
+
+#ifdef ENTRY_SYS_CPUS
+	cpu_data[0].state = STATE_RUNNING;
+#endif
+
+	/* Setup BSP mappings */
+	printk("SMP: bootstrap CPU ID is %d\n",bootstrap_processor);
+
+	cpu_set(bootstrap_processor, cpu_online_map);
+	cpu_set(bootstrap_processor, cpu_present_map);
+}
+
+
+
+/*
+** inventory.c:do_inventory() hasn't yet been run and thus we
+** don't 'discover' the additional CPU's until later.
+*/
+void __init smp_prepare_cpus(unsigned int max_cpus)
+{
+	cpus_clear(cpu_present_map);
+	cpu_set(0, cpu_present_map);
+
+	parisc_max_cpus = max_cpus;
+	if (!max_cpus)
+		printk(KERN_INFO "SMP mode deactivated.\n");
+}
+
+
+void smp_cpus_done(unsigned int cpu_max)
+{
+	return;
+}
+
+
+int __devinit __cpu_up(unsigned int cpu)
+{
+	if (cpu != 0 && cpu < parisc_max_cpus)
+		smp_boot_one_cpu(cpu);
+
+	return cpu_online(cpu) ? 0 : -ENOSYS;
+}
+
+
+
+#ifdef ENTRY_SYS_CPUS
+/* Code goes along with:
+**    entry.s:        ENTRY_NAME(sys_cpus)   / * 215, for cpu stat * /
+*/
+int sys_cpus(int argc, char **argv)
+{
+	int i,j=0;
+	extern int current_pid(int cpu);
+
+	if( argc > 2 ) {
+		printk("sys_cpus:Only one argument supported\n");
+		return (-1);
+	}
+	if ( argc == 1 ){
+	
+#ifdef DUMP_MORE_STATE
+		for(i=0; i<NR_CPUS; i++) {
+			int cpus_per_line = 4;
+			if(cpu_online(i)) {
+				if (j++ % cpus_per_line)
+					printk(" %3d",i);
+				else
+					printk("\n %3d",i);
+			}
+		}
+		printk("\n"); 
+#else
+	    	printk("\n 0\n"); 
+#endif
+	} else if((argc==2) && !(strcmp(argv[1],"-l"))) {
+		printk("\nCPUSTATE  TASK CPUNUM CPUID HARDCPU(HPA)\n");
+#ifdef DUMP_MORE_STATE
+		for(i=0;i<NR_CPUS;i++) {
+			if (!cpu_online(i))
+				continue;
+			if (cpu_data[i].cpuid != NO_PROC_ID) {
+				switch(cpu_data[i].state) {
+					case STATE_RENDEZVOUS:
+						printk("RENDEZVS ");
+						break;
+					case STATE_RUNNING:
+						printk((current_pid(i)!=0) ? "RUNNING  " : "IDLING   ");
+						break;
+					case STATE_STOPPED:
+						printk("STOPPED  ");
+						break;
+					case STATE_HALTED:
+						printk("HALTED   ");
+						break;
+					default:
+						printk("%08x?", cpu_data[i].state);
+						break;
+				}
+				if(cpu_online(i)) {
+					printk(" %4d",current_pid(i));
+				}	
+				printk(" %6d",cpu_number_map(i));
+				printk(" %5d",i);
+				printk(" 0x%lx\n",cpu_data[i].hpa);
+			}	
+		}
+#else
+		printk("\n%s  %4d      0     0 --------",
+			(current->pid)?"RUNNING ": "IDLING  ",current->pid); 
+#endif
+	} else if ((argc==2) && !(strcmp(argv[1],"-s"))) { 
+#ifdef DUMP_MORE_STATE
+     		printk("\nCPUSTATE   CPUID\n");
+		for (i=0;i<NR_CPUS;i++) {
+			if (!cpu_online(i))
+				continue;
+			if (cpu_data[i].cpuid != NO_PROC_ID) {
+				switch(cpu_data[i].state) {
+					case STATE_RENDEZVOUS:
+						printk("RENDEZVS");break;
+					case STATE_RUNNING:
+						printk((current_pid(i)!=0) ? "RUNNING " : "IDLING");
+						break;
+					case STATE_STOPPED:
+						printk("STOPPED ");break;
+					case STATE_HALTED:
+						printk("HALTED  ");break;
+					default:
+				}
+				printk("  %5d\n",i);
+			}	
+		}
+#else
+		printk("\n%s    CPU0",(current->pid==0)?"RUNNING ":"IDLING  "); 
+#endif
+	} else {
+		printk("sys_cpus:Unknown request\n");
+		return (-1);
+	}
+	return 0;
+}
+#endif /* ENTRY_SYS_CPUS */
+
+#ifdef CONFIG_PROC_FS
+int __init
+setup_profiling_timer(unsigned int multiplier)
+{
+	return -EINVAL;
+}
+#endif