1 files changed, 257 insertions, 49 deletions

diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index 233156f39b7f..e693812ac59a 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -15,6 +15,7 @@
  * This does not handle HOTPLUG_CPU yet.
  */
 #include <linux/sched.h>
+#include <linux/kernel_stat.h>
 #include <linux/err.h>
 #include <linux/smp.h>
 
@@ -35,6 +36,8 @@
 #include "xen-ops.h"
 #include "mmu.h"
 
+static void __cpuinit xen_init_lock_cpu(int cpu);
+
 cpumask_t xen_cpu_initialized_map;
 
 static DEFINE_PER_CPU(int, resched_irq);
@@ -66,13 +69,22 @@ static __cpuinit void cpu_bringup_and_idle(void)
         int cpu = smp_processor_id();
 
         cpu_init();
+        preempt_disable();
+
         xen_enable_sysenter();
+        xen_enable_syscall();
 
-        preempt_disable();
-        per_cpu(cpu_state, cpu) = CPU_ONLINE;
+        cpu = smp_processor_id();
+        smp_store_cpu_info(cpu);
+        cpu_data(cpu).x86_max_cores = 1;
+        set_cpu_sibling_map(cpu);
 
         xen_setup_cpu_clockevents();
 
+        cpu_set(cpu, cpu_online_map);
+        x86_write_percpu(cpu_state, CPU_ONLINE);
+        wmb();
+
         /* We can take interrupts now: we're officially "up". */
         local_irq_enable();
 
@@ -141,56 +153,39 @@ static int xen_smp_intr_init(unsigned int cpu)
         return rc;
 }
 
-void __init xen_fill_possible_map(void)
+static void __init xen_fill_possible_map(void)
 {
         int i, rc;
 
         for (i = 0; i < NR_CPUS; i++) {
                 rc = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
-                if (rc >= 0)
+                if (rc >= 0) {
+                        num_processors++;
                         cpu_set(i, cpu_possible_map);
+                }
         }
 }
 
-void __init xen_smp_prepare_boot_cpu(void)
+static void __init xen_smp_prepare_boot_cpu(void)
 {
-        int cpu;
-
         BUG_ON(smp_processor_id() != 0);
         native_smp_prepare_boot_cpu();
 
         /* We've switched to the "real" per-cpu gdt, so make sure the
            old memory can be recycled */
-        make_lowmem_page_readwrite(&per_cpu__gdt_page);
-
-        for_each_possible_cpu(cpu) {
-                cpus_clear(per_cpu(cpu_sibling_map, cpu));
-                /*
-                 * cpu_core_map lives in a per cpu area that is cleared
-                 * when the per cpu array is allocated.
-                 *
-                 * cpus_clear(per_cpu(cpu_core_map, cpu));
-                 */
-        }
+        make_lowmem_page_readwrite(&per_cpu_var(gdt_page));
 
         xen_setup_vcpu_info_placement();
 }
 
-void __init xen_smp_prepare_cpus(unsigned int max_cpus)
+static void __init xen_smp_prepare_cpus(unsigned int max_cpus)
 {
         unsigned cpu;
 
-        for_each_possible_cpu(cpu) {
-                cpus_clear(per_cpu(cpu_sibling_map, cpu));
-                /*
-                 * cpu_core_ map will be zeroed when the per
-                 * cpu area is allocated.
-                 *
-                 * cpus_clear(per_cpu(cpu_core_map, cpu));
-                 */
-        }
+        xen_init_lock_cpu(0);
 
         smp_store_cpu_info(0);
+        cpu_data(0).x86_max_cores = 1;
         set_cpu_sibling_map(0);
 
         if (xen_smp_intr_init(0))
@@ -225,7 +220,7 @@ static __cpuinit int
 cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 {
         struct vcpu_guest_context *ctxt;
-        struct gdt_page *gdt = &per_cpu(gdt_page, cpu);
+        struct desc_struct *gdt;
 
         if (cpu_test_and_set(cpu, xen_cpu_initialized_map))
                 return 0;
@@ -234,12 +229,15 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
         if (ctxt == NULL)
                 return -ENOMEM;
 
+        gdt = get_cpu_gdt_table(cpu);
+
         ctxt->flags = VGCF_IN_KERNEL;
         ctxt->user_regs.ds = __USER_DS;
         ctxt->user_regs.es = __USER_DS;
-        ctxt->user_regs.fs = __KERNEL_PERCPU;
-        ctxt->user_regs.gs = 0;
         ctxt->user_regs.ss = __KERNEL_DS;
+#ifdef CONFIG_X86_32
+        ctxt->user_regs.fs = __KERNEL_PERCPU;
+#endif
         ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
         ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
 
@@ -249,11 +247,11 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
 
         ctxt->ldt_ents = 0;
 
-        BUG_ON((unsigned long)gdt->gdt & ~PAGE_MASK);
-        make_lowmem_page_readonly(gdt->gdt);
+        BUG_ON((unsigned long)gdt & ~PAGE_MASK);
+        make_lowmem_page_readonly(gdt);
 
-        ctxt->gdt_frames[0] = virt_to_mfn(gdt->gdt);
-        ctxt->gdt_ents      = ARRAY_SIZE(gdt->gdt);
+        ctxt->gdt_frames[0] = virt_to_mfn(gdt);
+        ctxt->gdt_ents      = GDT_ENTRIES;
 
         ctxt->user_regs.cs = __KERNEL_CS;
         ctxt->user_regs.esp = idle->thread.sp0 - sizeof(struct pt_regs);
@@ -261,9 +259,11 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
         ctxt->kernel_ss = __KERNEL_DS;
         ctxt->kernel_sp = idle->thread.sp0;
 
+#ifdef CONFIG_X86_32
         ctxt->event_callback_cs     = __KERNEL_CS;
-        ctxt->event_callback_eip    = (unsigned long)xen_hypervisor_callback;
         ctxt->failsafe_callback_cs  = __KERNEL_CS;
+#endif
+        ctxt->event_callback_eip    = (unsigned long)xen_hypervisor_callback;
         ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback;
 
         per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
@@ -276,7 +276,7 @@ cpu_initialize_context(unsigned int cpu, struct task_struct *idle)
         return 0;
 }
 
-int __cpuinit xen_cpu_up(unsigned int cpu)
+static int __cpuinit xen_cpu_up(unsigned int cpu)
 {
         struct task_struct *idle = idle_task(cpu);
         int rc;
@@ -287,10 +287,28 @@ int __cpuinit xen_cpu_up(unsigned int cpu)
                 return rc;
 #endif
 
+#ifdef CONFIG_X86_64
+        /* Allocate node local memory for AP pdas */
+        WARN_ON(cpu == 0);
+        if (cpu > 0) {
+                rc = get_local_pda(cpu);
+                if (rc)
+                        return rc;
+        }
+#endif
+
+#ifdef CONFIG_X86_32
         init_gdt(cpu);
         per_cpu(current_task, cpu) = idle;
         irq_ctx_init(cpu);
+#else
+        cpu_pda(cpu)->pcurrent = idle;
+        clear_tsk_thread_flag(idle, TIF_FORK);
+#endif
         xen_setup_timer(cpu);
+        xen_init_lock_cpu(cpu);
+
+        per_cpu(cpu_state, cpu) = CPU_UP_PREPARE;
 
         /* make sure interrupts start blocked */
         per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
@@ -306,20 +324,18 @@ int __cpuinit xen_cpu_up(unsigned int cpu)
         if (rc)
                 return rc;
 
-        smp_store_cpu_info(cpu);
-        set_cpu_sibling_map(cpu);
-        /* This must be done before setting cpu_online_map */
-        wmb();
-
-        cpu_set(cpu, cpu_online_map);
-
         rc = HYPERVISOR_vcpu_op(VCPUOP_up, cpu, NULL);
         BUG_ON(rc);
 
+        while(per_cpu(cpu_state, cpu) != CPU_ONLINE) {
+                HYPERVISOR_sched_op(SCHEDOP_yield, 0);
+                barrier();
+        }
+
         return 0;
 }
 
-void xen_smp_cpus_done(unsigned int max_cpus)
+static void xen_smp_cpus_done(unsigned int max_cpus)
 {
 }
 
@@ -335,12 +351,12 @@ static void stop_self(void *v)
         BUG();
 }
 
-void xen_smp_send_stop(void)
+static void xen_smp_send_stop(void)
 {
         smp_call_function(stop_self, NULL, 0);
 }
 
-void xen_smp_send_reschedule(int cpu)
+static void xen_smp_send_reschedule(int cpu)
 {
         xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
 }
@@ -355,7 +371,7 @@ static void xen_send_IPI_mask(cpumask_t mask, enum ipi_vector vector)
                 xen_send_IPI_one(cpu, vector);
 }
 
-void xen_smp_send_call_function_ipi(cpumask_t mask)
+static void xen_smp_send_call_function_ipi(cpumask_t mask)
 {
         int cpu;
 
@@ -370,7 +386,7 @@ void xen_smp_send_call_function_ipi(cpumask_t mask)
         }
 }
 
-void xen_smp_send_call_function_single_ipi(int cpu)
+static void xen_smp_send_call_function_single_ipi(int cpu)
 {
         xen_send_IPI_mask(cpumask_of_cpu(cpu), XEN_CALL_FUNCTION_SINGLE_VECTOR);
 }
@@ -379,7 +395,11 @@ static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
 {
         irq_enter();
         generic_smp_call_function_interrupt();
+#ifdef CONFIG_X86_32
         __get_cpu_var(irq_stat).irq_call_count++;
+#else
+        add_pda(irq_call_count, 1);
+#endif
         irq_exit();
 
         return IRQ_HANDLED;
@@ -389,8 +409,196 @@ static irqreturn_t xen_call_function_single_interrupt(int irq, void *dev_id)
 {
         irq_enter();
         generic_smp_call_function_single_interrupt();
+#ifdef CONFIG_X86_32
         __get_cpu_var(irq_stat).irq_call_count++;
+#else
+        add_pda(irq_call_count, 1);
+#endif
         irq_exit();
 
         return IRQ_HANDLED;
 }
+
+struct xen_spinlock {
+        unsigned char lock;             /* 0 -> free; 1 -> locked */
+        unsigned short spinners;        /* count of waiting cpus */
+};
+
+static int xen_spin_is_locked(struct raw_spinlock *lock)
+{
+        struct xen_spinlock *xl = (struct xen_spinlock *)lock;
+
+        return xl->lock != 0;
+}
+
+static int xen_spin_is_contended(struct raw_spinlock *lock)
+{
+        struct xen_spinlock *xl = (struct xen_spinlock *)lock;
+
+        /* Not strictly true; this is only the count of contended
+           lock-takers entering the slow path. */
+        return xl->spinners != 0;
+}
+
+static int xen_spin_trylock(struct raw_spinlock *lock)
+{
+        struct xen_spinlock *xl = (struct xen_spinlock *)lock;
+        u8 old = 1;
+
+        asm("xchgb %b0,%1"
+            : "+q" (old), "+m" (xl->lock) : : "memory");
+
+        return old == 0;
+}
+
+static DEFINE_PER_CPU(int, lock_kicker_irq) = -1;
+static DEFINE_PER_CPU(struct xen_spinlock *, lock_spinners);
+
+static inline void spinning_lock(struct xen_spinlock *xl)
+{
+        __get_cpu_var(lock_spinners) = xl;
+        wmb();                  /* set lock of interest before count */
+        asm(LOCK_PREFIX " incw %0"
+            : "+m" (xl->spinners) : : "memory");
+}
+
+static inline void unspinning_lock(struct xen_spinlock *xl)
+{
+        asm(LOCK_PREFIX " decw %0"
+            : "+m" (xl->spinners) : : "memory");
+        wmb();                  /* decrement count before clearing lock */
+        __get_cpu_var(lock_spinners) = NULL;
+}
+
+static noinline int xen_spin_lock_slow(struct raw_spinlock *lock)
+{
+        struct xen_spinlock *xl = (struct xen_spinlock *)lock;
+        int irq = __get_cpu_var(lock_kicker_irq);
+        int ret;
+
+        /* If kicker interrupts not initialized yet, just spin */
+        if (irq == -1)
+                return 0;
+
+        /* announce we're spinning */
+        spinning_lock(xl);
+
+        /* clear pending */
+        xen_clear_irq_pending(irq);
+
+        /* check again make sure it didn't become free while
+           we weren't looking  */
+        ret = xen_spin_trylock(lock);
+        if (ret)
+                goto out;
+
+        /* block until irq becomes pending */
+        xen_poll_irq(irq);
+        kstat_this_cpu.irqs[irq]++;
+
+out:
+        unspinning_lock(xl);
+        return ret;
+}
+
+static void xen_spin_lock(struct raw_spinlock *lock)
+{
+        struct xen_spinlock *xl = (struct xen_spinlock *)lock;
+        int timeout;
+        u8 oldval;
+
+        do {
+                timeout = 1 << 10;
+
+                asm("1: xchgb %1,%0\n"
+                    "   testb %1,%1\n"
+                    "   jz 3f\n"
+                    "2: rep;nop\n"
+                    "   cmpb $0,%0\n"
+                    "   je 1b\n"
+                    "   dec %2\n"
+                    "   jnz 2b\n"
+                    "3:\n"
+                    : "+m" (xl->lock), "=q" (oldval), "+r" (timeout)
+                    : "1" (1)
+                    : "memory");
+
+        } while (unlikely(oldval != 0 && !xen_spin_lock_slow(lock)));
+}
+
+static noinline void xen_spin_unlock_slow(struct xen_spinlock *xl)
+{
+        int cpu;
+
+        for_each_online_cpu(cpu) {
+                /* XXX should mix up next cpu selection */
+                if (per_cpu(lock_spinners, cpu) == xl) {
+                        xen_send_IPI_one(cpu, XEN_SPIN_UNLOCK_VECTOR);
+                        break;
+                }
+        }
+}
+
+static void xen_spin_unlock(struct raw_spinlock *lock)
+{
+        struct xen_spinlock *xl = (struct xen_spinlock *)lock;
+
+        smp_wmb();              /* make sure no writes get moved after unlock */
+        xl->lock = 0;           /* release lock */
+
+        /* make sure unlock happens before kick */
+        barrier();
+
+        if (unlikely(xl->spinners))
+                xen_spin_unlock_slow(xl);
+}
+
+static __cpuinit void xen_init_lock_cpu(int cpu)
+{
+        int irq;
+        const char *name;
+
+        name = kasprintf(GFP_KERNEL, "spinlock%d", cpu);
+        irq = bind_ipi_to_irqhandler(XEN_SPIN_UNLOCK_VECTOR,
+                                     cpu,
+                                     xen_reschedule_interrupt,
+                                     IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
+                                     name,
+                                     NULL);
+
+        if (irq >= 0) {
+                disable_irq(irq); /* make sure it's never delivered */
+                per_cpu(lock_kicker_irq, cpu) = irq;
+        }
+
+        printk("cpu %d spinlock event irq %d\n", cpu, irq);
+}
+
+static void __init xen_init_spinlocks(void)
+{
+        pv_lock_ops.spin_is_locked = xen_spin_is_locked;
+        pv_lock_ops.spin_is_contended = xen_spin_is_contended;
+        pv_lock_ops.spin_lock = xen_spin_lock;
+        pv_lock_ops.spin_trylock = xen_spin_trylock;
+        pv_lock_ops.spin_unlock = xen_spin_unlock;
+}
+
+static const struct smp_ops xen_smp_ops __initdata = {
+        .smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
+        .smp_prepare_cpus = xen_smp_prepare_cpus,
+        .cpu_up = xen_cpu_up,
+        .smp_cpus_done = xen_smp_cpus_done,
+
+        .smp_send_stop = xen_smp_send_stop,
+        .smp_send_reschedule = xen_smp_send_reschedule,
+
+        .send_call_func_ipi = xen_smp_send_call_function_ipi,
+        .send_call_func_single_ipi = xen_smp_send_call_function_single_ipi,
+};
+
+void __init xen_smp_init(void)
+{
+        smp_ops = xen_smp_ops;
+        xen_fill_possible_map();
+        xen_init_spinlocks();
+}