* useful topology information for the kernel to make use of. As a
* result, all CPUs are treated as if they're single-core and
* single-threaded.
- *
- * This does not handle HOTPLUG_CPU yet.
*/
#include <linux/sched.h>
-#include <linux/kernel_stat.h>
#include <linux/err.h>
#include <linux/smp.h>
#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);
return IRQ_HANDLED;
}
-static __cpuinit void cpu_bringup_and_idle(void)
+static __cpuinit void cpu_bringup(void)
{
int cpu = smp_processor_id();
cpu_init();
+ touch_softlockup_watchdog();
preempt_disable();
xen_enable_sysenter();
local_irq_enable();
wmb(); /* make sure everything is out */
+}
+
+static __cpuinit void cpu_bringup_and_idle(void)
+{
+ cpu_bringup();
cpu_idle();
}
cpu_set(cpu, cpu_present_map);
}
-
- //init_xenbus_allowed_cpumask();
}
static __cpuinit int
struct task_struct *idle = idle_task(cpu);
int rc;
-#if 0
- rc = cpu_up_check(cpu);
- if (rc)
- return rc;
-#endif
-
#ifdef CONFIG_X86_64
/* Allocate node local memory for AP pdas */
WARN_ON(cpu == 0);
{
}
+#ifdef CONFIG_HOTPLUG_CPU
+static int xen_cpu_disable(void)
+{
+ unsigned int cpu = smp_processor_id();
+ if (cpu == 0)
+ return -EBUSY;
+
+ cpu_disable_common();
+
+ load_cr3(swapper_pg_dir);
+ return 0;
+}
+
+static void xen_cpu_die(unsigned int cpu)
+{
+ while (HYPERVISOR_vcpu_op(VCPUOP_is_up, cpu, NULL)) {
+ current->state = TASK_UNINTERRUPTIBLE;
+ schedule_timeout(HZ/10);
+ }
+ unbind_from_irqhandler(per_cpu(resched_irq, cpu), NULL);
+ unbind_from_irqhandler(per_cpu(callfunc_irq, cpu), NULL);
+ unbind_from_irqhandler(per_cpu(debug_irq, cpu), NULL);
+ unbind_from_irqhandler(per_cpu(callfuncsingle_irq, cpu), NULL);
+ xen_uninit_lock_cpu(cpu);
+ xen_teardown_timer(cpu);
+
+ if (num_online_cpus() == 1)
+ alternatives_smp_switch(0);
+}
+
+static void __cpuinit xen_play_dead(void) /* used only with CPU_HOTPLUG */
+{
+ play_dead_common();
+ HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL);
+ cpu_bringup();
+}
+
+#else /* !CONFIG_HOTPLUG_CPU */
+static int xen_cpu_disable(void)
+{
+ return -ENOSYS;
+}
+
+static void xen_cpu_die(unsigned int cpu)
+{
+ BUG();
+}
+
+static void xen_play_dead(void)
+{
+ BUG();
+}
+
+#endif
static void stop_self(void *v)
{
int cpu = smp_processor_id();
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,
+ .cpu_up = xen_cpu_up,
+ .cpu_die = xen_cpu_die,
+ .cpu_disable = xen_cpu_disable,
+ .play_dead = xen_play_dead,
+
.smp_send_stop = xen_smp_send_stop,
.smp_send_reschedule = xen_smp_send_reschedule,
projects / linux-2.6-omap-h63xx.git / blobdiff