Initial import

1 files changed, 342 insertions, 0 deletions

diff --git a/arch/ia64/kernel/smp.c b/arch/ia64/kernel/smp.c
new file mode 100644
index 000000000..7f706d4f8
--- /dev/null
+++ b/arch/ia64/kernel/smp.c
@@ -0,0 +1,342 @@
+/*
+ * SMP Support
+ *
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 1999, 2001, 2003 David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * Lots of stuff stolen from arch/alpha/kernel/smp.c
+ *
+ * 01/05/16 Rohit Seth <rohit.seth@intel.com>  IA64-SMP functions. Reorganized
+ * the existing code (on the lines of x86 port).
+ * 00/09/11 David Mosberger <davidm@hpl.hp.com> Do loops_per_jiffy
+ * calibration on each CPU.
+ * 00/08/23 Asit Mallick <asit.k.mallick@intel.com> fixed logical processor id
+ * 00/03/31 Rohit Seth <rohit.seth@intel.com>	Fixes for Bootstrap Processor
+ * & cpu_online_map now gets done here (instead of setup.c)
+ * 99/10/05 davidm	Update to bring it in sync with new command-line processing
+ *  scheme.
+ * 10/13/00 Goutham Rao <goutham.rao@intel.com> Updated smp_call_function and
+ *		smp_call_function_single to resend IPI on timeouts
+ */
+#include <linux/module.h>
+#include <linux/kernel.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/cache.h>
+#include <linux/delay.h>
+#include <linux/efi.h>
+#include <linux/bitops.h>
+#include <linux/kexec.h>
+
+#include <linux/atomic.h>
+#include <asm/current.h>
+#include <asm/delay.h>
+#include <asm/machvec.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/processor.h>
+#include <asm/ptrace.h>
+#include <asm/sal.h>
+#include <asm/tlbflush.h>
+#include <asm/unistd.h>
+#include <asm/mca.h>
+
+/*
+ * Note: alignment of 4 entries/cacheline was empirically determined
+ * to be a good tradeoff between hot cachelines & spreading the array
+ * across too many cacheline.
+ */
+static struct local_tlb_flush_counts {
+	unsigned int count;
+} __attribute__((__aligned__(32))) local_tlb_flush_counts[NR_CPUS];
+
+static DEFINE_PER_CPU_SHARED_ALIGNED(unsigned short [NR_CPUS],
+				     shadow_flush_counts);
+
+#define IPI_CALL_FUNC		0
+#define IPI_CPU_STOP		1
+#define IPI_CALL_FUNC_SINGLE	2
+#define IPI_KDUMP_CPU_STOP	3
+
+/* This needs to be cacheline aligned because it is written to by *other* CPUs.  */
+static DEFINE_PER_CPU_SHARED_ALIGNED(unsigned long, ipi_operation);
+
+extern void cpu_halt (void);
+
+static void
+stop_this_cpu(void)
+{
+	/*
+	 * Remove this CPU:
+	 */
+	set_cpu_online(smp_processor_id(), false);
+	max_xtp();
+	local_irq_disable();
+	cpu_halt();
+}
+
+void
+cpu_die(void)
+{
+	max_xtp();
+	local_irq_disable();
+	cpu_halt();
+	/* Should never be here */
+	BUG();
+	for (;;);
+}
+
+irqreturn_t
+handle_IPI (int irq, void *dev_id)
+{
+	int this_cpu = get_cpu();
+	unsigned long *pending_ipis = &__ia64_per_cpu_var(ipi_operation);
+	unsigned long ops;
+
+	mb();	/* Order interrupt and bit testing. */
+	while ((ops = xchg(pending_ipis, 0)) != 0) {
+		mb();	/* Order bit clearing and data access. */
+		do {
+			unsigned long which;
+
+			which = ffz(~ops);
+			ops &= ~(1 << which);
+
+			switch (which) {
+			case IPI_CPU_STOP:
+				stop_this_cpu();
+				break;
+			case IPI_CALL_FUNC:
+				generic_smp_call_function_interrupt();
+				break;
+			case IPI_CALL_FUNC_SINGLE:
+				generic_smp_call_function_single_interrupt();
+				break;
+#ifdef CONFIG_KEXEC
+			case IPI_KDUMP_CPU_STOP:
+				unw_init_running(kdump_cpu_freeze, NULL);
+				break;
+#endif
+			default:
+				printk(KERN_CRIT "Unknown IPI on CPU %d: %lu\n",
+						this_cpu, which);
+				break;
+			}
+		} while (ops);
+		mb();	/* Order data access and bit testing. */
+	}
+	put_cpu();
+	return IRQ_HANDLED;
+}
+
+
+
+/*
+ * Called with preemption disabled.
+ */
+static inline void
+send_IPI_single (int dest_cpu, int op)
+{
+	set_bit(op, &per_cpu(ipi_operation, dest_cpu));
+	platform_send_ipi(dest_cpu, IA64_IPI_VECTOR, IA64_IPI_DM_INT, 0);
+}
+
+/*
+ * Called with preemption disabled.
+ */
+static inline void
+send_IPI_allbutself (int op)
+{
+	unsigned int i;
+
+	for_each_online_cpu(i) {
+		if (i != smp_processor_id())
+			send_IPI_single(i, op);
+	}
+}
+
+/*
+ * Called with preemption disabled.
+ */
+static inline void
+send_IPI_mask(const struct cpumask *mask, int op)
+{
+	unsigned int cpu;
+
+	for_each_cpu(cpu, mask) {
+			send_IPI_single(cpu, op);
+	}
+}
+
+/*
+ * Called with preemption disabled.
+ */
+static inline void
+send_IPI_all (int op)
+{
+	int i;
+
+	for_each_online_cpu(i) {
+		send_IPI_single(i, op);
+	}
+}
+
+/*
+ * Called with preemption disabled.
+ */
+static inline void
+send_IPI_self (int op)
+{
+	send_IPI_single(smp_processor_id(), op);
+}
+
+#ifdef CONFIG_KEXEC
+void
+kdump_smp_send_stop(void)
+{
+ 	send_IPI_allbutself(IPI_KDUMP_CPU_STOP);
+}
+
+void
+kdump_smp_send_init(void)
+{
+	unsigned int cpu, self_cpu;
+	self_cpu = smp_processor_id();
+	for_each_online_cpu(cpu) {
+		if (cpu != self_cpu) {
+			if(kdump_status[cpu] == 0)
+				platform_send_ipi(cpu, 0, IA64_IPI_DM_INIT, 0);
+		}
+	}
+}
+#endif
+/*
+ * Called with preemption disabled.
+ */
+void
+smp_send_reschedule (int cpu)
+{
+	platform_send_ipi(cpu, IA64_IPI_RESCHEDULE, IA64_IPI_DM_INT, 0);
+}
+EXPORT_SYMBOL_GPL(smp_send_reschedule);
+
+/*
+ * Called with preemption disabled.
+ */
+static void
+smp_send_local_flush_tlb (int cpu)
+{
+	platform_send_ipi(cpu, IA64_IPI_LOCAL_TLB_FLUSH, IA64_IPI_DM_INT, 0);
+}
+
+void
+smp_local_flush_tlb(void)
+{
+	/*
+	 * Use atomic ops. Otherwise, the load/increment/store sequence from
+	 * a "++" operation can have the line stolen between the load & store.
+	 * The overhead of the atomic op in negligible in this case & offers
+	 * significant benefit for the brief periods where lots of cpus
+	 * are simultaneously flushing TLBs.
+	 */
+	ia64_fetchadd(1, &local_tlb_flush_counts[smp_processor_id()].count, acq);
+	local_flush_tlb_all();
+}
+
+#define FLUSH_DELAY	5 /* Usec backoff to eliminate excessive cacheline bouncing */
+
+void
+smp_flush_tlb_cpumask(cpumask_t xcpumask)
+{
+	unsigned short *counts = __ia64_per_cpu_var(shadow_flush_counts);
+	cpumask_t cpumask = xcpumask;
+	int mycpu, cpu, flush_mycpu = 0;
+
+	preempt_disable();
+	mycpu = smp_processor_id();
+
+	for_each_cpu(cpu, &cpumask)
+		counts[cpu] = local_tlb_flush_counts[cpu].count & 0xffff;
+
+	mb();
+	for_each_cpu(cpu, &cpumask) {
+		if (cpu == mycpu)
+			flush_mycpu = 1;
+		else
+			smp_send_local_flush_tlb(cpu);
+	}
+
+	if (flush_mycpu)
+		smp_local_flush_tlb();
+
+	for_each_cpu(cpu, &cpumask)
+		while(counts[cpu] == (local_tlb_flush_counts[cpu].count & 0xffff))
+			udelay(FLUSH_DELAY);
+
+	preempt_enable();
+}
+
+void
+smp_flush_tlb_all (void)
+{
+	on_each_cpu((void (*)(void *))local_flush_tlb_all, NULL, 1);
+}
+
+void
+smp_flush_tlb_mm (struct mm_struct *mm)
+{
+	cpumask_var_t cpus;
+	preempt_disable();
+	/* this happens for the common case of a single-threaded fork():  */
+	if (likely(mm == current->active_mm && atomic_read(&mm->mm_users) == 1))
+	{
+		local_finish_flush_tlb_mm(mm);
+		preempt_enable();
+		return;
+	}
+	if (!alloc_cpumask_var(&cpus, GFP_ATOMIC)) {
+		smp_call_function((void (*)(void *))local_finish_flush_tlb_mm,
+			mm, 1);
+	} else {
+		cpumask_copy(cpus, mm_cpumask(mm));
+		smp_call_function_many(cpus,
+			(void (*)(void *))local_finish_flush_tlb_mm, mm, 1);
+		free_cpumask_var(cpus);
+	}
+	local_irq_disable();
+	local_finish_flush_tlb_mm(mm);
+	local_irq_enable();
+	preempt_enable();
+}
+
+void arch_send_call_function_single_ipi(int cpu)
+{
+	send_IPI_single(cpu, IPI_CALL_FUNC_SINGLE);
+}
+
+void arch_send_call_function_ipi_mask(const struct cpumask *mask)
+{
+	send_IPI_mask(mask, IPI_CALL_FUNC);
+}
+
+/*
+ * this function calls the 'stop' function on all other CPUs in the system.
+ */
+void
+smp_send_stop (void)
+{
+	send_IPI_allbutself(IPI_CPU_STOP);
+}
+
+int
+setup_profiling_timer (unsigned int multiplier)
+{
+	return -EINVAL;
+}