xen: SMP guest support
This is a fairly straightforward Xen implementation of smp_ops. Xen has its own IPI mechanisms, and has no dependency on any APIC-based IPI. The smp_ops hooks and the flush_tlb_others pv_op allow a Xen guest to avoid all APIC code in arch/i386 (the only apic operation is a single apic_read for the apic version number). One subtle point which needs to be addressed is unpinning pagetables when another cpu may have a lazy tlb reference to the pagetable. Xen will not allow an in-use pagetable to be unpinned, so we must find any other cpus with a reference to the pagetable and get them to shoot down their references. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Chris Wright <chrisw@sous-sol.org> Cc: Benjamin LaHaise <bcrl@kvack.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Andi Kleen <ak@suse.de>
This commit is contained in:
Jeremy Fitzhardinge
Jeremy Fitzhardinge
parent
ab55028886
commit
f87e4cac4f
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@ -4,7 +4,7 @@
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config XEN
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bool "Enable support for Xen hypervisor"
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depends on PARAVIRT && X86_CMPXCHG && X86_TSC && !(PREEMPT || SMP || NEED_MULTIPLE_NODES)
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depends on PARAVIRT && X86_CMPXCHG && X86_TSC && !(PREEMPT || NEED_MULTIPLE_NODES)
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help
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This is the Linux Xen port. Enabling this will allow the
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kernel to boot in a paravirtualized environment under the
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@ -1,2 +1,4 @@
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obj-y := enlighten.o setup.o features.o multicalls.o mmu.o \
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events.o time.o
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obj-$(CONFIG_SMP) += smp.o
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@ -24,6 +24,7 @@
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#include <linux/mm.h>
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#include <linux/page-flags.h>
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#include <linux/highmem.h>
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#include <linux/smp.h>
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#include <xen/interface/xen.h>
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#include <xen/interface/physdev.h>
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@ -40,6 +41,7 @@
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#include <asm/setup.h>
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#include <asm/desc.h>
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#include <asm/pgtable.h>
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#include <asm/tlbflush.h>
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#include "xen-ops.h"
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#include "mmu.h"
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@ -56,7 +58,7 @@ DEFINE_PER_CPU(unsigned long, xen_cr3);
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struct start_info *xen_start_info;
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EXPORT_SYMBOL_GPL(xen_start_info);
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static void xen_vcpu_setup(int cpu)
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void xen_vcpu_setup(int cpu)
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{
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per_cpu(xen_vcpu, cpu) = &HYPERVISOR_shared_info->vcpu_info[cpu];
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}
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@ -347,23 +349,14 @@ static void xen_write_idt_entry(struct desc_struct *dt, int entrynum,
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}
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}
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/* Load a new IDT into Xen. In principle this can be per-CPU, so we
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hold a spinlock to protect the static traps[] array (static because
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it avoids allocation, and saves stack space). */
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static void xen_load_idt(const struct Xgt_desc_struct *desc)
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static void xen_convert_trap_info(const struct Xgt_desc_struct *desc,
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struct trap_info *traps)
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{
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static DEFINE_SPINLOCK(lock);
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static struct trap_info traps[257];
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int cpu = smp_processor_id();
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unsigned in, out, count;
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per_cpu(idt_desc, cpu) = *desc;
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count = (desc->size+1) / 8;
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BUG_ON(count > 256);
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spin_lock(&lock);
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for (in = out = 0; in < count; in++) {
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const u32 *entry = (u32 *)(desc->address + in * 8);
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@ -371,6 +364,31 @@ static void xen_load_idt(const struct Xgt_desc_struct *desc)
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out++;
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}
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traps[out].address = 0;
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}
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void xen_copy_trap_info(struct trap_info *traps)
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{
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const struct Xgt_desc_struct *desc = &get_cpu_var(idt_desc);
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xen_convert_trap_info(desc, traps);
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put_cpu_var(idt_desc);
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}
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/* Load a new IDT into Xen. In principle this can be per-CPU, so we
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hold a spinlock to protect the static traps[] array (static because
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it avoids allocation, and saves stack space). */
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static void xen_load_idt(const struct Xgt_desc_struct *desc)
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{
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static DEFINE_SPINLOCK(lock);
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static struct trap_info traps[257];
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int cpu = smp_processor_id();
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per_cpu(idt_desc, cpu) = *desc;
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spin_lock(&lock);
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xen_convert_trap_info(desc, traps);
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xen_mc_flush();
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if (HYPERVISOR_set_trap_table(traps))
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@ -428,6 +446,12 @@ static unsigned long xen_apic_read(unsigned long reg)
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{
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return 0;
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}
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static void xen_apic_write(unsigned long reg, unsigned long val)
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{
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/* Warn to see if there's any stray references */
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WARN_ON(1);
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}
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#endif
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static void xen_flush_tlb(void)
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@ -449,6 +473,40 @@ static void xen_flush_tlb_single(unsigned long addr)
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BUG();
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}
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static void xen_flush_tlb_others(const cpumask_t *cpus, struct mm_struct *mm,
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unsigned long va)
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{
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struct mmuext_op op;
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cpumask_t cpumask = *cpus;
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/*
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* A couple of (to be removed) sanity checks:
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*
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* - current CPU must not be in mask
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* - mask must exist :)
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*/
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BUG_ON(cpus_empty(cpumask));
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BUG_ON(cpu_isset(smp_processor_id(), cpumask));
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BUG_ON(!mm);
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/* If a CPU which we ran on has gone down, OK. */
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cpus_and(cpumask, cpumask, cpu_online_map);
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if (cpus_empty(cpumask))
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return;
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if (va == TLB_FLUSH_ALL) {
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op.cmd = MMUEXT_TLB_FLUSH_MULTI;
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op.arg2.vcpumask = (void *)cpus;
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} else {
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op.cmd = MMUEXT_INVLPG_MULTI;
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op.arg1.linear_addr = va;
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op.arg2.vcpumask = (void *)cpus;
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}
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if (HYPERVISOR_mmuext_op(&op, 1, NULL, DOMID_SELF))
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BUG();
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}
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static unsigned long xen_read_cr2(void)
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{
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return x86_read_percpu(xen_vcpu)->arch.cr2;
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@ -460,18 +518,6 @@ static void xen_write_cr4(unsigned long cr4)
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native_write_cr4(cr4 & ~X86_CR4_TSD);
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}
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/*
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* Page-directory addresses above 4GB do not fit into architectural %cr3.
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* When accessing %cr3, or equivalent field in vcpu_guest_context, guests
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* must use the following accessor macros to pack/unpack valid MFNs.
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*
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* Note that Xen is using the fact that the pagetable base is always
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* page-aligned, and putting the 12 MSB of the address into the 12 LSB
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* of cr3.
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*/
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#define xen_pfn_to_cr3(pfn) (((unsigned)(pfn) << 12) | ((unsigned)(pfn) >> 20))
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#define xen_cr3_to_pfn(cr3) (((unsigned)(cr3) >> 12) | ((unsigned)(cr3) << 20))
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static unsigned long xen_read_cr3(void)
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{
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return x86_read_percpu(xen_cr3);
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@ -740,8 +786,8 @@ static const struct paravirt_ops xen_paravirt_ops __initdata = {
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.io_delay = xen_io_delay,
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#ifdef CONFIG_X86_LOCAL_APIC
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.apic_write = paravirt_nop,
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.apic_write_atomic = paravirt_nop,
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.apic_write = xen_apic_write,
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.apic_write_atomic = xen_apic_write,
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.apic_read = xen_apic_read,
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.setup_boot_clock = paravirt_nop,
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.setup_secondary_clock = paravirt_nop,
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@ -751,6 +797,7 @@ static const struct paravirt_ops xen_paravirt_ops __initdata = {
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.flush_tlb_user = xen_flush_tlb,
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.flush_tlb_kernel = xen_flush_tlb,
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.flush_tlb_single = xen_flush_tlb_single,
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.flush_tlb_others = xen_flush_tlb_others,
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.pte_update = paravirt_nop,
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.pte_update_defer = paravirt_nop,
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@ -796,6 +843,19 @@ static const struct paravirt_ops xen_paravirt_ops __initdata = {
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.set_lazy_mode = xen_set_lazy_mode,
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};
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#ifdef CONFIG_SMP
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static const struct smp_ops xen_smp_ops __initdata = {
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.smp_prepare_boot_cpu = xen_smp_prepare_boot_cpu,
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.smp_prepare_cpus = xen_smp_prepare_cpus,
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.cpu_up = xen_cpu_up,
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.smp_cpus_done = xen_smp_cpus_done,
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.smp_send_stop = xen_smp_send_stop,
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.smp_send_reschedule = xen_smp_send_reschedule,
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.smp_call_function_mask = xen_smp_call_function_mask,
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};
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#endif /* CONFIG_SMP */
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/* First C function to be called on Xen boot */
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asmlinkage void __init xen_start_kernel(void)
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{
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@ -808,6 +868,9 @@ asmlinkage void __init xen_start_kernel(void)
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/* Install Xen paravirt ops */
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paravirt_ops = xen_paravirt_ops;
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#ifdef CONFIG_SMP
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smp_ops = xen_smp_ops;
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#endif
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xen_setup_features();
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@ -47,6 +47,9 @@ static DEFINE_SPINLOCK(irq_mapping_update_lock);
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/* IRQ <-> VIRQ mapping. */
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static DEFINE_PER_CPU(int, virq_to_irq[NR_VIRQS]) = {[0 ... NR_VIRQS-1] = -1};
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/* IRQ <-> IPI mapping */
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static DEFINE_PER_CPU(int, ipi_to_irq[XEN_NR_IPIS]) = {[0 ... XEN_NR_IPIS-1] = -1};
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/* Packed IRQ information: binding type, sub-type index, and event channel. */
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struct packed_irq
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{
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static struct packed_irq irq_info[NR_IRQS];
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/* Binding types. */
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enum { IRQT_UNBOUND, IRQT_PIRQ, IRQT_VIRQ, IRQT_IPI, IRQT_EVTCHN };
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enum {
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IRQT_UNBOUND,
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IRQT_PIRQ,
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IRQT_VIRQ,
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IRQT_IPI,
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IRQT_EVTCHN
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};
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/* Convenient shorthand for packed representation of an unbound IRQ. */
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#define IRQ_UNBOUND mk_irq_info(IRQT_UNBOUND, 0, 0)
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@ -261,6 +270,45 @@ static int bind_evtchn_to_irq(unsigned int evtchn)
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return irq;
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}
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static int bind_ipi_to_irq(unsigned int ipi, unsigned int cpu)
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{
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struct evtchn_bind_ipi bind_ipi;
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int evtchn, irq;
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spin_lock(&irq_mapping_update_lock);
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irq = per_cpu(ipi_to_irq, cpu)[ipi];
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if (irq == -1) {
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irq = find_unbound_irq();
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if (irq < 0)
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goto out;
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dynamic_irq_init(irq);
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set_irq_chip_and_handler_name(irq, &xen_dynamic_chip,
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handle_level_irq, "ipi");
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bind_ipi.vcpu = cpu;
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if (HYPERVISOR_event_channel_op(EVTCHNOP_bind_ipi,
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&bind_ipi) != 0)
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BUG();
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evtchn = bind_ipi.port;
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evtchn_to_irq[evtchn] = irq;
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irq_info[irq] = mk_irq_info(IRQT_IPI, ipi, evtchn);
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per_cpu(ipi_to_irq, cpu)[ipi] = irq;
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bind_evtchn_to_cpu(evtchn, cpu);
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}
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irq_bindcount[irq]++;
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out:
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spin_unlock(&irq_mapping_update_lock);
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return irq;
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}
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static int bind_virq_to_irq(unsigned int virq, unsigned int cpu)
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{
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struct evtchn_bind_virq bind_virq;
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@ -369,6 +417,28 @@ int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
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}
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EXPORT_SYMBOL_GPL(bind_virq_to_irqhandler);
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int bind_ipi_to_irqhandler(enum ipi_vector ipi,
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unsigned int cpu,
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irq_handler_t handler,
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unsigned long irqflags,
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const char *devname,
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void *dev_id)
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{
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int irq, retval;
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irq = bind_ipi_to_irq(ipi, cpu);
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if (irq < 0)
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return irq;
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retval = request_irq(irq, handler, irqflags, devname, dev_id);
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if (retval != 0) {
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unbind_from_irq(irq);
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return retval;
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}
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return irq;
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}
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void unbind_from_irqhandler(unsigned int irq, void *dev_id)
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{
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free_irq(irq, dev_id);
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@ -376,6 +446,14 @@ void unbind_from_irqhandler(unsigned int irq, void *dev_id)
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}
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EXPORT_SYMBOL_GPL(unbind_from_irqhandler);
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void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
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{
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int irq = per_cpu(ipi_to_irq, cpu)[vector];
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BUG_ON(irq < 0);
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notify_remote_via_irq(irq);
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}
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/*
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* Search the CPUs pending events bitmasks. For each one found, map
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* the event number to an irq, and feed it into do_IRQ() for
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@ -391,8 +391,12 @@ void xen_pgd_pin(pgd_t *pgd)
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xen_mc_batch();
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if (pgd_walk(pgd, pin_page, TASK_SIZE))
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if (pgd_walk(pgd, pin_page, TASK_SIZE)) {
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/* re-enable interrupts for kmap_flush_unused */
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xen_mc_issue(0);
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kmap_flush_unused();
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xen_mc_batch();
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}
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mcs = __xen_mc_entry(sizeof(*op));
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op = mcs.args;
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@ -474,27 +478,58 @@ void xen_dup_mmap(struct mm_struct *oldmm, struct mm_struct *mm)
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spin_unlock(&mm->page_table_lock);
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}
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void xen_exit_mmap(struct mm_struct *mm)
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#ifdef CONFIG_SMP
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/* Another cpu may still have their %cr3 pointing at the pagetable, so
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we need to repoint it somewhere else before we can unpin it. */
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static void drop_other_mm_ref(void *info)
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{
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struct task_struct *tsk = current;
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struct mm_struct *mm = info;
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task_lock(tsk);
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if (__get_cpu_var(cpu_tlbstate).active_mm == mm)
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leave_mm(smp_processor_id());
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}
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/*
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* We aggressively remove defunct pgd from cr3. We execute unmap_vmas()
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* *much* faster this way, as no tlb flushes means bigger wrpt batches.
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*/
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if (tsk->active_mm == mm) {
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tsk->active_mm = &init_mm;
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atomic_inc(&init_mm.mm_count);
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switch_mm(mm, &init_mm, tsk);
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atomic_dec(&mm->mm_count);
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BUG_ON(atomic_read(&mm->mm_count) == 0);
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static void drop_mm_ref(struct mm_struct *mm)
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{
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if (current->active_mm == mm) {
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if (current->mm == mm)
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load_cr3(swapper_pg_dir);
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else
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leave_mm(smp_processor_id());
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}
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task_unlock(tsk);
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if (!cpus_empty(mm->cpu_vm_mask))
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xen_smp_call_function_mask(mm->cpu_vm_mask, drop_other_mm_ref,
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mm, 1);
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}
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#else
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static void drop_mm_ref(struct mm_struct *mm)
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{
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if (current->active_mm == mm)
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load_cr3(swapper_pg_dir);
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}
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#endif
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/*
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* While a process runs, Xen pins its pagetables, which means that the
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* hypervisor forces it to be read-only, and it controls all updates
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* to it. This means that all pagetable updates have to go via the
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* hypervisor, which is moderately expensive.
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*
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* Since we're pulling the pagetable down, we switch to use init_mm,
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* unpin old process pagetable and mark it all read-write, which
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* allows further operations on it to be simple memory accesses.
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*
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* The only subtle point is that another CPU may be still using the
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* pagetable because of lazy tlb flushing. This means we need need to
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* switch all CPUs off this pagetable before we can unpin it.
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*/
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void xen_exit_mmap(struct mm_struct *mm)
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{
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get_cpu(); /* make sure we don't move around */
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drop_mm_ref(mm);
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put_cpu();
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xen_pgd_unpin(mm->pgd);
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}
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@ -3,6 +3,19 @@
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#include <linux/linkage.h>
|
||||
#include <asm/page.h>
|
||||
|
||||
/*
|
||||
* Page-directory addresses above 4GB do not fit into architectural %cr3.
|
||||
* When accessing %cr3, or equivalent field in vcpu_guest_context, guests
|
||||
* must use the following accessor macros to pack/unpack valid MFNs.
|
||||
*
|
||||
* Note that Xen is using the fact that the pagetable base is always
|
||||
* page-aligned, and putting the 12 MSB of the address into the 12 LSB
|
||||
* of cr3.
|
||||
*/
|
||||
#define xen_pfn_to_cr3(pfn) (((unsigned)(pfn) << 12) | ((unsigned)(pfn) >> 20))
|
||||
#define xen_cr3_to_pfn(cr3) (((unsigned)(cr3) >> 12) | ((unsigned)(cr3) << 20))
|
||||
|
||||
|
||||
void set_pte_mfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);
|
||||
|
||||
void xen_set_pte(pte_t *ptep, pte_t pteval);
|
||||
|
|
|
|||
|
|
@ -94,4 +94,9 @@ void __init xen_arch_setup(void)
|
|||
COMMAND_LINE_SIZE : MAX_GUEST_CMDLINE);
|
||||
|
||||
pm_idle = xen_idle;
|
||||
|
||||
#ifdef CONFIG_SMP
|
||||
/* fill cpus_possible with all available cpus */
|
||||
xen_fill_possible_map();
|
||||
#endif
|
||||
}
|
||||
|
|
|
|||
|
|
@ -0,0 +1,407 @@
|
|||
/*
|
||||
* Xen SMP support
|
||||
*
|
||||
* This file implements the Xen versions of smp_ops. SMP under Xen is
|
||||
* very straightforward. Bringing a CPU up is simply a matter of
|
||||
* loading its initial context and setting it running.
|
||||
*
|
||||
* IPIs are handled through the Xen event mechanism.
|
||||
*
|
||||
* Because virtual CPUs can be scheduled onto any real CPU, there's no
|
||||
* 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/err.h>
|
||||
#include <linux/smp.h>
|
||||
|
||||
#include <asm/paravirt.h>
|
||||
#include <asm/desc.h>
|
||||
#include <asm/pgtable.h>
|
||||
#include <asm/cpu.h>
|
||||
|
||||
#include <xen/interface/xen.h>
|
||||
#include <xen/interface/vcpu.h>
|
||||
|
||||
#include <asm/xen/interface.h>
|
||||
#include <asm/xen/hypercall.h>
|
||||
|
||||
#include <xen/page.h>
|
||||
#include <xen/events.h>
|
||||
|
||||
#include "xen-ops.h"
|
||||
#include "mmu.h"
|
||||
|
||||
static cpumask_t cpu_initialized_map;
|
||||
static DEFINE_PER_CPU(int, resched_irq);
|
||||
static DEFINE_PER_CPU(int, callfunc_irq);
|
||||
|
||||
/*
|
||||
* Structure and data for smp_call_function(). This is designed to minimise
|
||||
* static memory requirements. It also looks cleaner.
|
||||
*/
|
||||
static DEFINE_SPINLOCK(call_lock);
|
||||
|
||||
struct call_data_struct {
|
||||
void (*func) (void *info);
|
||||
void *info;
|
||||
atomic_t started;
|
||||
atomic_t finished;
|
||||
int wait;
|
||||
};
|
||||
|
||||
static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id);
|
||||
|
||||
static struct call_data_struct *call_data;
|
||||
|
||||
/*
|
||||
* Reschedule call back. Nothing to do,
|
||||
* all the work is done automatically when
|
||||
* we return from the interrupt.
|
||||
*/
|
||||
static irqreturn_t xen_reschedule_interrupt(int irq, void *dev_id)
|
||||
{
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
static __cpuinit void cpu_bringup_and_idle(void)
|
||||
{
|
||||
int cpu = smp_processor_id();
|
||||
|
||||
cpu_init();
|
||||
|
||||
preempt_disable();
|
||||
per_cpu(cpu_state, cpu) = CPU_ONLINE;
|
||||
|
||||
xen_setup_cpu_clockevents();
|
||||
|
||||
/* We can take interrupts now: we're officially "up". */
|
||||
local_irq_enable();
|
||||
|
||||
wmb(); /* make sure everything is out */
|
||||
cpu_idle();
|
||||
}
|
||||
|
||||
static int xen_smp_intr_init(unsigned int cpu)
|
||||
{
|
||||
int rc;
|
||||
const char *resched_name, *callfunc_name;
|
||||
|
||||
per_cpu(resched_irq, cpu) = per_cpu(callfunc_irq, cpu) = -1;
|
||||
|
||||
resched_name = kasprintf(GFP_KERNEL, "resched%d", cpu);
|
||||
rc = bind_ipi_to_irqhandler(XEN_RESCHEDULE_VECTOR,
|
||||
cpu,
|
||||
xen_reschedule_interrupt,
|
||||
IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
|
||||
resched_name,
|
||||
NULL);
|
||||
if (rc < 0)
|
||||
goto fail;
|
||||
per_cpu(resched_irq, cpu) = rc;
|
||||
|
||||
callfunc_name = kasprintf(GFP_KERNEL, "callfunc%d", cpu);
|
||||
rc = bind_ipi_to_irqhandler(XEN_CALL_FUNCTION_VECTOR,
|
||||
cpu,
|
||||
xen_call_function_interrupt,
|
||||
IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
|
||||
callfunc_name,
|
||||
NULL);
|
||||
if (rc < 0)
|
||||
goto fail;
|
||||
per_cpu(callfunc_irq, cpu) = rc;
|
||||
|
||||
return 0;
|
||||
|
||||
fail:
|
||||
if (per_cpu(resched_irq, cpu) >= 0)
|
||||
unbind_from_irqhandler(per_cpu(resched_irq, cpu), NULL);
|
||||
if (per_cpu(callfunc_irq, cpu) >= 0)
|
||||
unbind_from_irqhandler(per_cpu(callfunc_irq, cpu), NULL);
|
||||
return rc;
|
||||
}
|
||||
|
||||
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)
|
||||
cpu_set(i, cpu_possible_map);
|
||||
}
|
||||
}
|
||||
|
||||
void __init xen_smp_prepare_boot_cpu(void)
|
||||
{
|
||||
int cpu;
|
||||
|
||||
BUG_ON(smp_processor_id() != 0);
|
||||
native_smp_prepare_boot_cpu();
|
||||
|
||||
xen_vcpu_setup(0);
|
||||
|
||||
/* 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 (cpu = 0; cpu < NR_CPUS; cpu++) {
|
||||
cpus_clear(cpu_sibling_map[cpu]);
|
||||
cpus_clear(cpu_core_map[cpu]);
|
||||
}
|
||||
}
|
||||
|
||||
void __init xen_smp_prepare_cpus(unsigned int max_cpus)
|
||||
{
|
||||
unsigned cpu;
|
||||
|
||||
for (cpu = 0; cpu < NR_CPUS; cpu++) {
|
||||
cpus_clear(cpu_sibling_map[cpu]);
|
||||
cpus_clear(cpu_core_map[cpu]);
|
||||
}
|
||||
|
||||
smp_store_cpu_info(0);
|
||||
set_cpu_sibling_map(0);
|
||||
|
||||
if (xen_smp_intr_init(0))
|
||||
BUG();
|
||||
|
||||
cpu_initialized_map = cpumask_of_cpu(0);
|
||||
|
||||
/* Restrict the possible_map according to max_cpus. */
|
||||
while ((num_possible_cpus() > 1) && (num_possible_cpus() > max_cpus)) {
|
||||
for (cpu = NR_CPUS-1; !cpu_isset(cpu, cpu_possible_map); cpu--)
|
||||
continue;
|
||||
cpu_clear(cpu, cpu_possible_map);
|
||||
}
|
||||
|
||||
for_each_possible_cpu (cpu) {
|
||||
struct task_struct *idle;
|
||||
|
||||
if (cpu == 0)
|
||||
continue;
|
||||
|
||||
idle = fork_idle(cpu);
|
||||
if (IS_ERR(idle))
|
||||
panic("failed fork for CPU %d", cpu);
|
||||
|
||||
cpu_set(cpu, cpu_present_map);
|
||||
}
|
||||
|
||||
//init_xenbus_allowed_cpumask();
|
||||
}
|
||||
|
||||
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);
|
||||
|
||||
if (cpu_test_and_set(cpu, cpu_initialized_map))
|
||||
return 0;
|
||||
|
||||
ctxt = kzalloc(sizeof(*ctxt), GFP_KERNEL);
|
||||
if (ctxt == NULL)
|
||||
return -ENOMEM;
|
||||
|
||||
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;
|
||||
ctxt->user_regs.eip = (unsigned long)cpu_bringup_and_idle;
|
||||
ctxt->user_regs.eflags = 0x1000; /* IOPL_RING1 */
|
||||
|
||||
memset(&ctxt->fpu_ctxt, 0, sizeof(ctxt->fpu_ctxt));
|
||||
|
||||
xen_copy_trap_info(ctxt->trap_ctxt);
|
||||
|
||||
ctxt->ldt_ents = 0;
|
||||
|
||||
BUG_ON((unsigned long)gdt->gdt & ~PAGE_MASK);
|
||||
make_lowmem_page_readonly(gdt->gdt);
|
||||
|
||||
ctxt->gdt_frames[0] = virt_to_mfn(gdt->gdt);
|
||||
ctxt->gdt_ents = ARRAY_SIZE(gdt->gdt);
|
||||
|
||||
ctxt->user_regs.cs = __KERNEL_CS;
|
||||
ctxt->user_regs.esp = idle->thread.esp0 - sizeof(struct pt_regs);
|
||||
|
||||
ctxt->kernel_ss = __KERNEL_DS;
|
||||
ctxt->kernel_sp = idle->thread.esp0;
|
||||
|
||||
ctxt->event_callback_cs = __KERNEL_CS;
|
||||
ctxt->event_callback_eip = (unsigned long)xen_hypervisor_callback;
|
||||
ctxt->failsafe_callback_cs = __KERNEL_CS;
|
||||
ctxt->failsafe_callback_eip = (unsigned long)xen_failsafe_callback;
|
||||
|
||||
per_cpu(xen_cr3, cpu) = __pa(swapper_pg_dir);
|
||||
ctxt->ctrlreg[3] = xen_pfn_to_cr3(virt_to_mfn(swapper_pg_dir));
|
||||
|
||||
if (HYPERVISOR_vcpu_op(VCPUOP_initialise, cpu, ctxt))
|
||||
BUG();
|
||||
|
||||
kfree(ctxt);
|
||||
return 0;
|
||||
}
|
||||
|
||||
int __cpuinit xen_cpu_up(unsigned int cpu)
|
||||
{
|
||||
struct task_struct *idle = idle_task(cpu);
|
||||
int rc;
|
||||
|
||||
#if 0
|
||||
rc = cpu_up_check(cpu);
|
||||
if (rc)
|
||||
return rc;
|
||||
#endif
|
||||
|
||||
init_gdt(cpu);
|
||||
per_cpu(current_task, cpu) = idle;
|
||||
xen_vcpu_setup(cpu);
|
||||
irq_ctx_init(cpu);
|
||||
xen_setup_timer(cpu);
|
||||
|
||||
/* make sure interrupts start blocked */
|
||||
per_cpu(xen_vcpu, cpu)->evtchn_upcall_mask = 1;
|
||||
|
||||
rc = cpu_initialize_context(cpu, idle);
|
||||
if (rc)
|
||||
return rc;
|
||||
|
||||
if (num_online_cpus() == 1)
|
||||
alternatives_smp_switch(1);
|
||||
|
||||
rc = xen_smp_intr_init(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);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
void xen_smp_cpus_done(unsigned int max_cpus)
|
||||
{
|
||||
}
|
||||
|
||||
static void stop_self(void *v)
|
||||
{
|
||||
int cpu = smp_processor_id();
|
||||
|
||||
/* make sure we're not pinning something down */
|
||||
load_cr3(swapper_pg_dir);
|
||||
/* should set up a minimal gdt */
|
||||
|
||||
HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
|
||||
BUG();
|
||||
}
|
||||
|
||||
void xen_smp_send_stop(void)
|
||||
{
|
||||
cpumask_t mask = cpu_online_map;
|
||||
cpu_clear(smp_processor_id(), mask);
|
||||
xen_smp_call_function_mask(mask, stop_self, NULL, 0);
|
||||
}
|
||||
|
||||
void xen_smp_send_reschedule(int cpu)
|
||||
{
|
||||
xen_send_IPI_one(cpu, XEN_RESCHEDULE_VECTOR);
|
||||
}
|
||||
|
||||
|
||||
static void xen_send_IPI_mask(cpumask_t mask, enum ipi_vector vector)
|
||||
{
|
||||
unsigned cpu;
|
||||
|
||||
cpus_and(mask, mask, cpu_online_map);
|
||||
|
||||
for_each_cpu_mask(cpu, mask)
|
||||
xen_send_IPI_one(cpu, vector);
|
||||
}
|
||||
|
||||
static irqreturn_t xen_call_function_interrupt(int irq, void *dev_id)
|
||||
{
|
||||
void (*func) (void *info) = call_data->func;
|
||||
void *info = call_data->info;
|
||||
int wait = call_data->wait;
|
||||
|
||||
/*
|
||||
* Notify initiating CPU that I've grabbed the data and am
|
||||
* about to execute the function
|
||||
*/
|
||||
mb();
|
||||
atomic_inc(&call_data->started);
|
||||
/*
|
||||
* At this point the info structure may be out of scope unless wait==1
|
||||
*/
|
||||
irq_enter();
|
||||
(*func)(info);
|
||||
irq_exit();
|
||||
|
||||
if (wait) {
|
||||
mb(); /* commit everything before setting finished */
|
||||
atomic_inc(&call_data->finished);
|
||||
}
|
||||
|
||||
return IRQ_HANDLED;
|
||||
}
|
||||
|
||||
int xen_smp_call_function_mask(cpumask_t mask, void (*func)(void *),
|
||||
void *info, int wait)
|
||||
{
|
||||
struct call_data_struct data;
|
||||
int cpus;
|
||||
|
||||
/* Holding any lock stops cpus from going down. */
|
||||
spin_lock(&call_lock);
|
||||
|
||||
cpu_clear(smp_processor_id(), mask);
|
||||
|
||||
cpus = cpus_weight(mask);
|
||||
if (!cpus) {
|
||||
spin_unlock(&call_lock);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Can deadlock when called with interrupts disabled */
|
||||
WARN_ON(irqs_disabled());
|
||||
|
||||
data.func = func;
|
||||
data.info = info;
|
||||
atomic_set(&data.started, 0);
|
||||
data.wait = wait;
|
||||
if (wait)
|
||||
atomic_set(&data.finished, 0);
|
||||
|
||||
call_data = &data;
|
||||
mb(); /* write everything before IPI */
|
||||
|
||||
/* Send a message to other CPUs and wait for them to respond */
|
||||
xen_send_IPI_mask(mask, XEN_CALL_FUNCTION_VECTOR);
|
||||
|
||||
/* Make sure other vcpus get a chance to run.
|
||||
XXX too severe? Maybe we should check the other CPU's states? */
|
||||
HYPERVISOR_sched_op(SCHEDOP_yield, 0);
|
||||
|
||||
/* Wait for response */
|
||||
while (atomic_read(&data.started) != cpus ||
|
||||
(wait && atomic_read(&data.finished) != cpus))
|
||||
cpu_relax();
|
||||
|
||||
spin_unlock(&call_lock);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
@ -519,7 +519,7 @@ static irqreturn_t xen_timer_interrupt(int irq, void *dev_id)
|
|||
return ret;
|
||||
}
|
||||
|
||||
static void xen_setup_timer(int cpu)
|
||||
void xen_setup_timer(int cpu)
|
||||
{
|
||||
const char *name;
|
||||
struct clock_event_device *evt;
|
||||
|
|
@ -535,16 +535,20 @@ static void xen_setup_timer(int cpu)
|
|||
IRQF_DISABLED|IRQF_PERCPU|IRQF_NOBALANCING,
|
||||
name, NULL);
|
||||
|
||||
evt = &get_cpu_var(xen_clock_events);
|
||||
evt = &per_cpu(xen_clock_events, cpu);
|
||||
memcpy(evt, xen_clockevent, sizeof(*evt));
|
||||
|
||||
evt->cpumask = cpumask_of_cpu(cpu);
|
||||
evt->irq = irq;
|
||||
clockevents_register_device(evt);
|
||||
|
||||
setup_runstate_info(cpu);
|
||||
}
|
||||
|
||||
put_cpu_var(xen_clock_events);
|
||||
void xen_setup_cpu_clockevents(void)
|
||||
{
|
||||
BUG_ON(preemptible());
|
||||
|
||||
clockevents_register_device(&__get_cpu_var(xen_clock_events));
|
||||
}
|
||||
|
||||
__init void xen_time_init(void)
|
||||
|
|
@ -570,4 +574,5 @@ __init void xen_time_init(void)
|
|||
tsc_disable = 0;
|
||||
|
||||
xen_setup_timer(cpu);
|
||||
xen_setup_cpu_clockevents();
|
||||
}
|
||||
|
|
|
|||
|
|
@ -3,6 +3,12 @@
|
|||
|
||||
#include <linux/init.h>
|
||||
|
||||
/* These are code, but not functions. Defined in entry.S */
|
||||
extern const char xen_hypervisor_callback[];
|
||||
extern const char xen_failsafe_callback[];
|
||||
|
||||
void xen_copy_trap_info(struct trap_info *traps);
|
||||
|
||||
DECLARE_PER_CPU(struct vcpu_info *, xen_vcpu);
|
||||
DECLARE_PER_CPU(unsigned long, xen_cr3);
|
||||
|
||||
|
|
@ -13,6 +19,8 @@ char * __init xen_memory_setup(void);
|
|||
void __init xen_arch_setup(void);
|
||||
void __init xen_init_IRQ(void);
|
||||
|
||||
void xen_setup_timer(int cpu);
|
||||
void xen_setup_cpu_clockevents(void);
|
||||
unsigned long xen_cpu_khz(void);
|
||||
void __init xen_time_init(void);
|
||||
unsigned long xen_get_wallclock(void);
|
||||
|
|
@ -28,5 +36,22 @@ static inline unsigned xen_get_lazy_mode(void)
|
|||
return x86_read_percpu(xen_lazy_mode);
|
||||
}
|
||||
|
||||
void __init xen_fill_possible_map(void);
|
||||
|
||||
void xen_vcpu_setup(int cpu);
|
||||
void xen_smp_prepare_boot_cpu(void);
|
||||
void xen_smp_prepare_cpus(unsigned int max_cpus);
|
||||
int xen_cpu_up(unsigned int cpu);
|
||||
void xen_smp_cpus_done(unsigned int max_cpus);
|
||||
|
||||
void xen_smp_send_stop(void);
|
||||
void xen_smp_send_reschedule(int cpu);
|
||||
int xen_smp_call_function (void (*func) (void *info), void *info, int nonatomic,
|
||||
int wait);
|
||||
int xen_smp_call_function_single(int cpu, void (*func) (void *info), void *info,
|
||||
int nonatomic, int wait);
|
||||
|
||||
int xen_smp_call_function_mask(cpumask_t mask, void (*func)(void *),
|
||||
void *info, int wait);
|
||||
|
||||
#endif /* XEN_OPS_H */
|
||||
|
|
|
|||
|
|
@ -1,15 +1,32 @@
|
|||
#ifndef _XEN_EVENTS_H
|
||||
#define _XEN_EVENTS_H
|
||||
|
||||
#include <linux/irq.h>
|
||||
#include <linux/interrupt.h>
|
||||
|
||||
#include <xen/interface/event_channel.h>
|
||||
#include <asm/xen/hypercall.h>
|
||||
|
||||
enum ipi_vector {
|
||||
XEN_RESCHEDULE_VECTOR,
|
||||
XEN_CALL_FUNCTION_VECTOR,
|
||||
|
||||
XEN_NR_IPIS,
|
||||
};
|
||||
|
||||
int bind_evtchn_to_irqhandler(unsigned int evtchn,
|
||||
irqreturn_t (*handler)(int, void *),
|
||||
irq_handler_t handler,
|
||||
unsigned long irqflags, const char *devname,
|
||||
void *dev_id);
|
||||
int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
|
||||
irqreturn_t (*handler)(int, void *),
|
||||
unsigned long irqflags, const char *devname, void *dev_id);
|
||||
irq_handler_t handler,
|
||||
unsigned long irqflags, const char *devname,
|
||||
void *dev_id);
|
||||
int bind_ipi_to_irqhandler(enum ipi_vector ipi,
|
||||
unsigned int cpu,
|
||||
irq_handler_t handler,
|
||||
unsigned long irqflags,
|
||||
const char *devname,
|
||||
void *dev_id);
|
||||
|
||||
/*
|
||||
* Common unbind function for all event sources. Takes IRQ to unbind from.
|
||||
|
|
@ -18,6 +35,8 @@ int bind_virq_to_irqhandler(unsigned int virq, unsigned int cpu,
|
|||
*/
|
||||
void unbind_from_irqhandler(unsigned int irq, void *dev_id);
|
||||
|
||||
void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector);
|
||||
|
||||
static inline void notify_remote_via_evtchn(int port)
|
||||
{
|
||||
struct evtchn_send send = { .port = port };
|
||||
|
|
|
|||
Loading…
Reference in New Issue