linux/arch/ia64/xen/irq_xen.c
Tejun Heo c6e22f9e3e percpu: make percpu symbols in xen unique
This patch updates percpu related symbols in xen such that percpu
symbols are unique and don't clash with local symbols.  This serves
two purposes of decreasing the possibility of global percpu symbol
collision and allowing dropping per_cpu__ prefix from percpu symbols.

* arch/x86/xen/smp.c, arch/x86/xen/time.c, arch/ia64/xen/irq_xen.c:
  add xen_ prefix to percpu variables

* arch/ia64/xen/time.c: add xen_ prefix to percpu variables, drop
  processed_ prefix and make them static

Partly based on Rusty Russell's "alloc_percpu: rename percpu vars
which cause name clashes" patch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
2009-10-29 22:34:13 +09:00

439 lines
12 KiB
C

/******************************************************************************
* arch/ia64/xen/irq_xen.c
*
* Copyright (c) 2008 Isaku Yamahata <yamahata at valinux co jp>
* VA Linux Systems Japan K.K.
*
* 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.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/cpu.h>
#include <xen/interface/xen.h>
#include <xen/interface/callback.h>
#include <xen/events.h>
#include <asm/xen/privop.h>
#include "irq_xen.h"
/***************************************************************************
* pv_irq_ops
* irq operations
*/
static int
xen_assign_irq_vector(int irq)
{
struct physdev_irq irq_op;
irq_op.irq = irq;
if (HYPERVISOR_physdev_op(PHYSDEVOP_alloc_irq_vector, &irq_op))
return -ENOSPC;
return irq_op.vector;
}
static void
xen_free_irq_vector(int vector)
{
struct physdev_irq irq_op;
if (vector < IA64_FIRST_DEVICE_VECTOR ||
vector > IA64_LAST_DEVICE_VECTOR)
return;
irq_op.vector = vector;
if (HYPERVISOR_physdev_op(PHYSDEVOP_free_irq_vector, &irq_op))
printk(KERN_WARNING "%s: xen_free_irq_vecotr fail vector=%d\n",
__func__, vector);
}
static DEFINE_PER_CPU(int, xen_timer_irq) = -1;
static DEFINE_PER_CPU(int, xen_ipi_irq) = -1;
static DEFINE_PER_CPU(int, xen_resched_irq) = -1;
static DEFINE_PER_CPU(int, xen_cmc_irq) = -1;
static DEFINE_PER_CPU(int, xen_cmcp_irq) = -1;
static DEFINE_PER_CPU(int, xen_cpep_irq) = -1;
#define NAME_SIZE 15
static DEFINE_PER_CPU(char[NAME_SIZE], xen_timer_name);
static DEFINE_PER_CPU(char[NAME_SIZE], xen_ipi_name);
static DEFINE_PER_CPU(char[NAME_SIZE], xen_resched_name);
static DEFINE_PER_CPU(char[NAME_SIZE], xen_cmc_name);
static DEFINE_PER_CPU(char[NAME_SIZE], xen_cmcp_name);
static DEFINE_PER_CPU(char[NAME_SIZE], xen_cpep_name);
#undef NAME_SIZE
struct saved_irq {
unsigned int irq;
struct irqaction *action;
};
/* 16 should be far optimistic value, since only several percpu irqs
* are registered early.
*/
#define MAX_LATE_IRQ 16
static struct saved_irq saved_percpu_irqs[MAX_LATE_IRQ];
static unsigned short late_irq_cnt;
static unsigned short saved_irq_cnt;
static int xen_slab_ready;
#ifdef CONFIG_SMP
/* Dummy stub. Though we may check XEN_RESCHEDULE_VECTOR before __do_IRQ,
* it ends up to issue several memory accesses upon percpu data and
* thus adds unnecessary traffic to other paths.
*/
static irqreturn_t
xen_dummy_handler(int irq, void *dev_id)
{
return IRQ_HANDLED;
}
static struct irqaction xen_ipi_irqaction = {
.handler = handle_IPI,
.flags = IRQF_DISABLED,
.name = "IPI"
};
static struct irqaction xen_resched_irqaction = {
.handler = xen_dummy_handler,
.flags = IRQF_DISABLED,
.name = "resched"
};
static struct irqaction xen_tlb_irqaction = {
.handler = xen_dummy_handler,
.flags = IRQF_DISABLED,
.name = "tlb_flush"
};
#endif
/*
* This is xen version percpu irq registration, which needs bind
* to xen specific evtchn sub-system. One trick here is that xen
* evtchn binding interface depends on kmalloc because related
* port needs to be freed at device/cpu down. So we cache the
* registration on BSP before slab is ready and then deal them
* at later point. For rest instances happening after slab ready,
* we hook them to xen evtchn immediately.
*
* FIXME: MCA is not supported by far, and thus "nomca" boot param is
* required.
*/
static void
__xen_register_percpu_irq(unsigned int cpu, unsigned int vec,
struct irqaction *action, int save)
{
struct irq_desc *desc;
int irq = 0;
if (xen_slab_ready) {
switch (vec) {
case IA64_TIMER_VECTOR:
snprintf(per_cpu(xen_timer_name, cpu),
sizeof(per_cpu(xen_timer_name, cpu)),
"%s%d", action->name, cpu);
irq = bind_virq_to_irqhandler(VIRQ_ITC, cpu,
action->handler, action->flags,
per_cpu(xen_timer_name, cpu), action->dev_id);
per_cpu(xen_timer_irq, cpu) = irq;
break;
case IA64_IPI_RESCHEDULE:
snprintf(per_cpu(xen_resched_name, cpu),
sizeof(per_cpu(xen_resched_name, cpu)),
"%s%d", action->name, cpu);
irq = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR, cpu,
action->handler, action->flags,
per_cpu(xen_resched_name, cpu), action->dev_id);
per_cpu(xen_resched_irq, cpu) = irq;
break;
case IA64_IPI_VECTOR:
snprintf(per_cpu(xen_ipi_name, cpu),
sizeof(per_cpu(xen_ipi_name, cpu)),
"%s%d", action->name, cpu);
irq = bind_ipi_to_irqhandler(XEN_IPI_VECTOR, cpu,
action->handler, action->flags,
per_cpu(xen_ipi_name, cpu), action->dev_id);
per_cpu(xen_ipi_irq, cpu) = irq;
break;
case IA64_CMC_VECTOR:
snprintf(per_cpu(xen_cmc_name, cpu),
sizeof(per_cpu(xen_cmc_name, cpu)),
"%s%d", action->name, cpu);
irq = bind_virq_to_irqhandler(VIRQ_MCA_CMC, cpu,
action->handler,
action->flags,
per_cpu(xen_cmc_name, cpu),
action->dev_id);
per_cpu(xen_cmc_irq, cpu) = irq;
break;
case IA64_CMCP_VECTOR:
snprintf(per_cpu(xen_cmcp_name, cpu),
sizeof(per_cpu(xen_cmcp_name, cpu)),
"%s%d", action->name, cpu);
irq = bind_ipi_to_irqhandler(XEN_CMCP_VECTOR, cpu,
action->handler,
action->flags,
per_cpu(xen_cmcp_name, cpu),
action->dev_id);
per_cpu(xen_cmcp_irq, cpu) = irq;
break;
case IA64_CPEP_VECTOR:
snprintf(per_cpu(xen_cpep_name, cpu),
sizeof(per_cpu(xen_cpep_name, cpu)),
"%s%d", action->name, cpu);
irq = bind_ipi_to_irqhandler(XEN_CPEP_VECTOR, cpu,
action->handler,
action->flags,
per_cpu(xen_cpep_name, cpu),
action->dev_id);
per_cpu(xen_cpep_irq, cpu) = irq;
break;
case IA64_CPE_VECTOR:
case IA64_MCA_RENDEZ_VECTOR:
case IA64_PERFMON_VECTOR:
case IA64_MCA_WAKEUP_VECTOR:
case IA64_SPURIOUS_INT_VECTOR:
/* No need to complain, these aren't supported. */
break;
default:
printk(KERN_WARNING "Percpu irq %d is unsupported "
"by xen!\n", vec);
break;
}
BUG_ON(irq < 0);
if (irq > 0) {
/*
* Mark percpu. Without this, migrate_irqs() will
* mark the interrupt for migrations and trigger it
* on cpu hotplug.
*/
desc = irq_desc + irq;
desc->status |= IRQ_PER_CPU;
}
}
/* For BSP, we cache registered percpu irqs, and then re-walk
* them when initializing APs
*/
if (!cpu && save) {
BUG_ON(saved_irq_cnt == MAX_LATE_IRQ);
saved_percpu_irqs[saved_irq_cnt].irq = vec;
saved_percpu_irqs[saved_irq_cnt].action = action;
saved_irq_cnt++;
if (!xen_slab_ready)
late_irq_cnt++;
}
}
static void
xen_register_percpu_irq(ia64_vector vec, struct irqaction *action)
{
__xen_register_percpu_irq(smp_processor_id(), vec, action, 1);
}
static void
xen_bind_early_percpu_irq(void)
{
int i;
xen_slab_ready = 1;
/* There's no race when accessing this cached array, since only
* BSP will face with such step shortly
*/
for (i = 0; i < late_irq_cnt; i++)
__xen_register_percpu_irq(smp_processor_id(),
saved_percpu_irqs[i].irq,
saved_percpu_irqs[i].action, 0);
}
/* FIXME: There's no obvious point to check whether slab is ready. So
* a hack is used here by utilizing a late time hook.
*/
#ifdef CONFIG_HOTPLUG_CPU
static int __devinit
unbind_evtchn_callback(struct notifier_block *nfb,
unsigned long action, void *hcpu)
{
unsigned int cpu = (unsigned long)hcpu;
if (action == CPU_DEAD) {
/* Unregister evtchn. */
if (per_cpu(xen_cpep_irq, cpu) >= 0) {
unbind_from_irqhandler(per_cpu(xen_cpep_irq, cpu),
NULL);
per_cpu(xen_cpep_irq, cpu) = -1;
}
if (per_cpu(xen_cmcp_irq, cpu) >= 0) {
unbind_from_irqhandler(per_cpu(xen_cmcp_irq, cpu),
NULL);
per_cpu(xen_cmcp_irq, cpu) = -1;
}
if (per_cpu(xen_cmc_irq, cpu) >= 0) {
unbind_from_irqhandler(per_cpu(xen_cmc_irq, cpu), NULL);
per_cpu(xen_cmc_irq, cpu) = -1;
}
if (per_cpu(xen_ipi_irq, cpu) >= 0) {
unbind_from_irqhandler(per_cpu(xen_ipi_irq, cpu), NULL);
per_cpu(xen_ipi_irq, cpu) = -1;
}
if (per_cpu(xen_resched_irq, cpu) >= 0) {
unbind_from_irqhandler(per_cpu(xen_resched_irq, cpu),
NULL);
per_cpu(xen_resched_irq, cpu) = -1;
}
if (per_cpu(xen_timer_irq, cpu) >= 0) {
unbind_from_irqhandler(per_cpu(xen_timer_irq, cpu),
NULL);
per_cpu(xen_timer_irq, cpu) = -1;
}
}
return NOTIFY_OK;
}
static struct notifier_block unbind_evtchn_notifier = {
.notifier_call = unbind_evtchn_callback,
.priority = 0
};
#endif
void xen_smp_intr_init_early(unsigned int cpu)
{
#ifdef CONFIG_SMP
unsigned int i;
for (i = 0; i < saved_irq_cnt; i++)
__xen_register_percpu_irq(cpu, saved_percpu_irqs[i].irq,
saved_percpu_irqs[i].action, 0);
#endif
}
void xen_smp_intr_init(void)
{
#ifdef CONFIG_SMP
unsigned int cpu = smp_processor_id();
struct callback_register event = {
.type = CALLBACKTYPE_event,
.address = { .ip = (unsigned long)&xen_event_callback },
};
if (cpu == 0) {
/* Initialization was already done for boot cpu. */
#ifdef CONFIG_HOTPLUG_CPU
/* Register the notifier only once. */
register_cpu_notifier(&unbind_evtchn_notifier);
#endif
return;
}
/* This should be piggyback when setup vcpu guest context */
BUG_ON(HYPERVISOR_callback_op(CALLBACKOP_register, &event));
#endif /* CONFIG_SMP */
}
void __init
xen_irq_init(void)
{
struct callback_register event = {
.type = CALLBACKTYPE_event,
.address = { .ip = (unsigned long)&xen_event_callback },
};
xen_init_IRQ();
BUG_ON(HYPERVISOR_callback_op(CALLBACKOP_register, &event));
late_time_init = xen_bind_early_percpu_irq;
}
void
xen_platform_send_ipi(int cpu, int vector, int delivery_mode, int redirect)
{
#ifdef CONFIG_SMP
/* TODO: we need to call vcpu_up here */
if (unlikely(vector == ap_wakeup_vector)) {
/* XXX
* This should be in __cpu_up(cpu) in ia64 smpboot.c
* like x86. But don't want to modify it,
* keep it untouched.
*/
xen_smp_intr_init_early(cpu);
xen_send_ipi(cpu, vector);
/* vcpu_prepare_and_up(cpu); */
return;
}
#endif
switch (vector) {
case IA64_IPI_VECTOR:
xen_send_IPI_one(cpu, XEN_IPI_VECTOR);
break;
case IA64_IPI_RESCHEDULE:
xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
break;
case IA64_CMCP_VECTOR:
xen_send_IPI_one(cpu, XEN_CMCP_VECTOR);
break;
case IA64_CPEP_VECTOR:
xen_send_IPI_one(cpu, XEN_CPEP_VECTOR);
break;
case IA64_TIMER_VECTOR: {
/* this is used only once by check_sal_cache_flush()
at boot time */
static int used = 0;
if (!used) {
xen_send_ipi(cpu, IA64_TIMER_VECTOR);
used = 1;
break;
}
/* fallthrough */
}
default:
printk(KERN_WARNING "Unsupported IPI type 0x%x\n",
vector);
notify_remote_via_irq(0); /* defaults to 0 irq */
break;
}
}
static void __init
xen_register_ipi(void)
{
#ifdef CONFIG_SMP
register_percpu_irq(IA64_IPI_VECTOR, &xen_ipi_irqaction);
register_percpu_irq(IA64_IPI_RESCHEDULE, &xen_resched_irqaction);
register_percpu_irq(IA64_IPI_LOCAL_TLB_FLUSH, &xen_tlb_irqaction);
#endif
}
static void
xen_resend_irq(unsigned int vector)
{
(void)resend_irq_on_evtchn(vector);
}
const struct pv_irq_ops xen_irq_ops __initdata = {
.register_ipi = xen_register_ipi,
.assign_irq_vector = xen_assign_irq_vector,
.free_irq_vector = xen_free_irq_vector,
.register_percpu_irq = xen_register_percpu_irq,
.resend_irq = xen_resend_irq,
};