From 0d1edf46ba229b46efacf75c0544b88c05a7b266 Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Mon, 28 Jul 2008 11:53:57 -0700 Subject: xen: compile irq functions without -pg for ftrace For some reason I managed to miss a bunch of irq-related functions which also need to be compiled without -pg when using ftrace. This patch moves them into their own file, and starts a cleanup process I've been meaning to do anyway. Signed-off-by: Jeremy Fitzhardinge Cc: Sam Ravnborg Cc: "Alex Nixon (Intern)" Cc: Eduardo Habkost Signed-off-by: Ingo Molnar --- arch/x86/xen/irq.c | 143 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 143 insertions(+) create mode 100644 arch/x86/xen/irq.c (limited to 'arch/x86/xen/irq.c') diff --git a/arch/x86/xen/irq.c b/arch/x86/xen/irq.c new file mode 100644 index 0000000..28b85ab --- /dev/null +++ b/arch/x86/xen/irq.c @@ -0,0 +1,143 @@ +#include + +#include +#include +#include + +#include +#include + +#include "xen-ops.h" + +/* + * Force a proper event-channel callback from Xen after clearing the + * callback mask. We do this in a very simple manner, by making a call + * down into Xen. The pending flag will be checked by Xen on return. + */ +void xen_force_evtchn_callback(void) +{ + (void)HYPERVISOR_xen_version(0, NULL); +} + +static void __init __xen_init_IRQ(void) +{ +#ifdef CONFIG_X86_64 + int i; + + /* Create identity vector->irq map */ + for(i = 0; i < NR_VECTORS; i++) { + int cpu; + + for_each_possible_cpu(cpu) + per_cpu(vector_irq, cpu)[i] = i; + } +#endif /* CONFIG_X86_64 */ + + xen_init_IRQ(); +} + +static unsigned long xen_save_fl(void) +{ + struct vcpu_info *vcpu; + unsigned long flags; + + vcpu = x86_read_percpu(xen_vcpu); + + /* flag has opposite sense of mask */ + flags = !vcpu->evtchn_upcall_mask; + + /* convert to IF type flag + -0 -> 0x00000000 + -1 -> 0xffffffff + */ + return (-flags) & X86_EFLAGS_IF; +} + +static void xen_restore_fl(unsigned long flags) +{ + struct vcpu_info *vcpu; + + /* convert from IF type flag */ + flags = !(flags & X86_EFLAGS_IF); + + /* There's a one instruction preempt window here. We need to + make sure we're don't switch CPUs between getting the vcpu + pointer and updating the mask. */ + preempt_disable(); + vcpu = x86_read_percpu(xen_vcpu); + vcpu->evtchn_upcall_mask = flags; + preempt_enable_no_resched(); + + /* Doesn't matter if we get preempted here, because any + pending event will get dealt with anyway. */ + + if (flags == 0) { + preempt_check_resched(); + barrier(); /* unmask then check (avoid races) */ + if (unlikely(vcpu->evtchn_upcall_pending)) + xen_force_evtchn_callback(); + } +} + +static void xen_irq_disable(void) +{ + /* There's a one instruction preempt window here. We need to + make sure we're don't switch CPUs between getting the vcpu + pointer and updating the mask. */ + preempt_disable(); + x86_read_percpu(xen_vcpu)->evtchn_upcall_mask = 1; + preempt_enable_no_resched(); +} + +static void xen_irq_enable(void) +{ + struct vcpu_info *vcpu; + + /* We don't need to worry about being preempted here, since + either a) interrupts are disabled, so no preemption, or b) + the caller is confused and is trying to re-enable interrupts + on an indeterminate processor. */ + + vcpu = x86_read_percpu(xen_vcpu); + vcpu->evtchn_upcall_mask = 0; + + /* Doesn't matter if we get preempted here, because any + pending event will get dealt with anyway. */ + + barrier(); /* unmask then check (avoid races) */ + if (unlikely(vcpu->evtchn_upcall_pending)) + xen_force_evtchn_callback(); +} + +static void xen_safe_halt(void) +{ + /* Blocking includes an implicit local_irq_enable(). */ + if (HYPERVISOR_sched_op(SCHEDOP_block, NULL) != 0) + BUG(); +} + +static void xen_halt(void) +{ + if (irqs_disabled()) + HYPERVISOR_vcpu_op(VCPUOP_down, smp_processor_id(), NULL); + else + xen_safe_halt(); +} + +static const struct pv_irq_ops xen_irq_ops __initdata = { + .init_IRQ = __xen_init_IRQ, + .save_fl = xen_save_fl, + .restore_fl = xen_restore_fl, + .irq_disable = xen_irq_disable, + .irq_enable = xen_irq_enable, + .safe_halt = xen_safe_halt, + .halt = xen_halt, +#ifdef CONFIG_X86_64 + .adjust_exception_frame = xen_adjust_exception_frame, +#endif +}; + +void __init xen_init_irq_ops() +{ + pv_irq_ops = xen_irq_ops; +} -- cgit v1.1