On Wed, 1 Aug 2012, Konrad Rzeszutek Wilk wrote:
On Thu, Jul 26, 2012 at 04:33:57PM +0100, Stefano Stabellini wrote:
Compile events.c on ARM. Parse, map and enable the IRQ to get event notifications from the device tree (node "/xen").
On ARM Linux irqs are not enabled by default:
- call enable_percpu_irq for xen_events_irq (drivers are supposed
to call enable_irq after request_irq);
- reset the IRQ_NOAUTOEN and IRQ_NOREQUEST flags that are enabled by
default on ARM. If IRQ_NOAUTOEN is set, __setup_irq doesn't call irq_startup, that is responsible for calling irq_unmask at startup time. As a result event channels remain masked.
Signed-off-by: Stefano Stabellini stefano.stabellini@eu.citrix.com
arch/arm/xen/enlighten.c | 33 +++++++++++++++++++++++++++++++++ arch/x86/xen/enlighten.c | 1 + arch/x86/xen/irq.c | 1 + arch/x86/xen/xen-ops.h | 1 - drivers/xen/events.c | 18 +++++++++++++++--- include/xen/events.h | 2 ++ 6 files changed, 52 insertions(+), 4 deletions(-)
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c index 854af1e..60d6d36 100644 --- a/arch/arm/xen/enlighten.c +++ b/arch/arm/xen/enlighten.c @@ -7,8 +7,11 @@ #include <xen/grant_table.h> #include <xen/hvm.h> #include <xen/xenbus.h> +#include <xen/events.h> #include <asm/xen/hypervisor.h> #include <asm/xen/hypercall.h> +#include <linux/interrupt.h> +#include <linux/irqreturn.h> #include <linux/module.h> #include <linux/of.h> #include <linux/of_irq.h> @@ -33,6 +36,8 @@ EXPORT_SYMBOL_GPL(xen_have_vector_callback); int xen_platform_pci_unplug = XEN_UNPLUG_ALL; EXPORT_SYMBOL_GPL(xen_platform_pci_unplug); +static __read_mostly int xen_events_irq = -1;
int xen_remap_domain_mfn_range(struct vm_area_struct *vma, unsigned long addr, unsigned long mfn, int nr, @@ -65,6 +70,9 @@ int __init xen_guest_init(void) if (of_address_to_resource(node, 0, &res)) return -EINVAL; xen_hvm_resume_frames = res.start >> PAGE_SHIFT;
- xen_events_irq = irq_of_parse_and_map(node, 0);
- pr_info("Xen support found, events_irq=%d gnttab_frame_pfn=%lx\n",
xen_events_irq, xen_hvm_resume_frames);xen_setup_features(); @@ -114,3 +122,28 @@ int __init xen_guest_init(void) } EXPORT_SYMBOL_GPL(xen_guest_init); core_initcall(xen_guest_init);
+static irqreturn_t xen_arm_callback(int irq, void *arg) +{
- xen_hvm_evtchn_do_upcall();
- return 0;
Um, IRQ_HANDLED?
Yep
+}
+static int __init xen_init_events(void) +{
- if (!xen_domain() || xen_events_irq < 0)
return -ENODEV;- xen_init_IRQ();
- if (request_percpu_irq(xen_events_irq, xen_arm_callback,
"events", xen_vcpu)) {pr_err("Error requesting IRQ %d\n", xen_events_irq);return -EINVAL;- }
- enable_percpu_irq(xen_events_irq, 0);
- return 0;
+} +postcore_initcall(xen_init_events); diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 6131d43..5a30502 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -33,6 +33,7 @@ #include <linux/memblock.h> #include <xen/xen.h> +#include <xen/events.h> #include <xen/interface/xen.h> #include <xen/interface/version.h> #include <xen/interface/physdev.h> diff --git a/arch/x86/xen/irq.c b/arch/x86/xen/irq.c index 1573376..01a4dc0 100644 --- a/arch/x86/xen/irq.c +++ b/arch/x86/xen/irq.c @@ -5,6 +5,7 @@ #include <xen/interface/xen.h> #include <xen/interface/sched.h> #include <xen/interface/vcpu.h> +#include <xen/events.h> #include <asm/xen/hypercall.h> #include <asm/xen/hypervisor.h> diff --git a/arch/x86/xen/xen-ops.h b/arch/x86/xen/xen-ops.h index 202d4c1..2368295 100644 --- a/arch/x86/xen/xen-ops.h +++ b/arch/x86/xen/xen-ops.h @@ -35,7 +35,6 @@ void xen_set_pat(u64); char * __init xen_memory_setup(void); void __init xen_arch_setup(void); -void __init xen_init_IRQ(void); void xen_enable_sysenter(void); void xen_enable_syscall(void); void xen_vcpu_restore(void); diff --git a/drivers/xen/events.c b/drivers/xen/events.c index 7da65d3..9b506b2 100644 --- a/drivers/xen/events.c +++ b/drivers/xen/events.c @@ -31,14 +31,16 @@ #include <linux/irqnr.h> #include <linux/pci.h> +#ifdef CONFIG_X86 #include <asm/desc.h> #include <asm/ptrace.h> #include <asm/irq.h> #include <asm/idle.h> #include <asm/io_apic.h> -#include <asm/sync_bitops.h> #include <asm/xen/page.h> #include <asm/xen/pci.h> +#endif +#include <asm/sync_bitops.h> #include <asm/xen/hypercall.h> #include <asm/xen/hypervisor.h> @@ -50,6 +52,9 @@ #include <xen/interface/event_channel.h> #include <xen/interface/hvm/hvm_op.h> #include <xen/interface/hvm/params.h> +#include <xen/interface/physdev.h> +#include <xen/interface/sched.h> +#include <asm/hw_irq.h> /*
- This lock protects updates to the following mapping and reference-count
@@ -834,6 +839,7 @@ int bind_evtchn_to_irq(unsigned int evtchn) struct irq_info *info = info_for_irq(irq); WARN_ON(info == NULL || info->type != IRQT_EVTCHN); }
- irq_clear_status_flags(irq, IRQ_NOREQUEST|IRQ_NOAUTOEN);
I feel that this should be its own commit by itself. I am not certain of the implication of this on x86 and I think it deserves some explanation.
OK. It shouldn't have any effects on x86, considering that both IRQ_NOREQUEST and IRQ_NOAUTOEN are not set there.
out: mutex_unlock(&irq_mapping_update_lock); @@ -1377,7 +1383,9 @@ void xen_evtchn_do_upcall(struct pt_regs *regs) { struct pt_regs *old_regs = set_irq_regs(regs); +#ifdef CONFIG_X86 exit_idle(); +#endif
Doesn't exist? Or is that it does not need it?
It does not exist.