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authorLinus Torvalds <torvalds@linux-foundation.org>2012-07-24 12:01:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-07-24 12:01:20 -0700
commit5fecc9d8f59e765c2a48379dd7c6f5cf88c7d75a (patch)
treed1fc25d9650d3ac24591bba6f5e2e7a1afc54796 /arch/x86/kernel
parent3c4cfadef6a1665d9cd02a543782d03d3e6740c6 (diff)
parent1a577b72475d161b6677c05abe57301362023bb2 (diff)
Merge tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Avi Kivity: "Highlights include - full big real mode emulation on pre-Westmere Intel hosts (can be disabled with emulate_invalid_guest_state=0) - relatively small ppc and s390 updates - PCID/INVPCID support in guests - EOI avoidance; 3.6 guests should perform better on 3.6 hosts on interrupt intensive workloads) - Lockless write faults during live migration - EPT accessed/dirty bits support for new Intel processors" Fix up conflicts in: - Documentation/virtual/kvm/api.txt: Stupid subchapter numbering, added next to each other. - arch/powerpc/kvm/booke_interrupts.S: PPC asm changes clashing with the KVM fixes - arch/s390/include/asm/sigp.h, arch/s390/kvm/sigp.c: Duplicated commits through the kvm tree and the s390 tree, with subsequent edits in the KVM tree. * tag 'kvm-3.6-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (93 commits) KVM: fix race with level interrupts x86, hyper: fix build with !CONFIG_KVM_GUEST Revert "apic: fix kvm build on UP without IOAPIC" KVM guest: switch to apic_set_eoi_write, apic_write apic: add apic_set_eoi_write for PV use KVM: VMX: Implement PCID/INVPCID for guests with EPT KVM: Add x86_hyper_kvm to complete detect_hypervisor_platform check KVM: PPC: Critical interrupt emulation support KVM: PPC: e500mc: Fix tlbilx emulation for 64-bit guests KVM: PPC64: booke: Set interrupt computation mode for 64-bit host KVM: PPC: bookehv: Add ESR flag to Data Storage Interrupt KVM: PPC: bookehv64: Add support for std/ld emulation. booke: Added crit/mc exception handler for e500v2 booke/bookehv: Add host crit-watchdog exception support KVM: MMU: document mmu-lock and fast page fault KVM: MMU: fix kvm_mmu_pagetable_walk tracepoint KVM: MMU: trace fast page fault KVM: MMU: fast path of handling guest page fault KVM: MMU: introduce SPTE_MMU_WRITEABLE bit KVM: MMU: fold tlb flush judgement into mmu_spte_update ...
Diffstat (limited to 'arch/x86/kernel')
-rw-r--r--arch/x86/kernel/apic/apic.c17
-rw-r--r--arch/x86/kernel/cpu/hypervisor.c3
-rw-r--r--arch/x86/kernel/kvm.c64
3 files changed, 81 insertions, 3 deletions
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index c421512ca5eb..98e24131ff3a 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2143,6 +2143,23 @@ int default_cpu_mask_to_apicid_and(const struct cpumask *cpumask,
}
/*
+ * Override the generic EOI implementation with an optimized version.
+ * Only called during early boot when only one CPU is active and with
+ * interrupts disabled, so we know this does not race with actual APIC driver
+ * use.
+ */
+void __init apic_set_eoi_write(void (*eoi_write)(u32 reg, u32 v))
+{
+ struct apic **drv;
+
+ for (drv = __apicdrivers; drv < __apicdrivers_end; drv++) {
+ /* Should happen once for each apic */
+ WARN_ON((*drv)->eoi_write == eoi_write);
+ (*drv)->eoi_write = eoi_write;
+ }
+}
+
+/*
* Power management
*/
#ifdef CONFIG_PM
diff --git a/arch/x86/kernel/cpu/hypervisor.c b/arch/x86/kernel/cpu/hypervisor.c
index 755f64fb0743..a8f8fa9769d6 100644
--- a/arch/x86/kernel/cpu/hypervisor.c
+++ b/arch/x86/kernel/cpu/hypervisor.c
@@ -37,6 +37,9 @@ static const __initconst struct hypervisor_x86 * const hypervisors[] =
#endif
&x86_hyper_vmware,
&x86_hyper_ms_hyperv,
+#ifdef CONFIG_KVM_GUEST
+ &x86_hyper_kvm,
+#endif
};
const struct hypervisor_x86 *x86_hyper;
diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index e554e5ad2fe8..c1d61ee4b4f1 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -39,6 +39,9 @@
#include <asm/desc.h>
#include <asm/tlbflush.h>
#include <asm/idle.h>
+#include <asm/apic.h>
+#include <asm/apicdef.h>
+#include <asm/hypervisor.h>
static int kvmapf = 1;
@@ -283,6 +286,22 @@ static void kvm_register_steal_time(void)
cpu, __pa(st));
}
+static DEFINE_PER_CPU(unsigned long, kvm_apic_eoi) = KVM_PV_EOI_DISABLED;
+
+static void kvm_guest_apic_eoi_write(u32 reg, u32 val)
+{
+ /**
+ * This relies on __test_and_clear_bit to modify the memory
+ * in a way that is atomic with respect to the local CPU.
+ * The hypervisor only accesses this memory from the local CPU so
+ * there's no need for lock or memory barriers.
+ * An optimization barrier is implied in apic write.
+ */
+ if (__test_and_clear_bit(KVM_PV_EOI_BIT, &__get_cpu_var(kvm_apic_eoi)))
+ return;
+ apic_write(APIC_EOI, APIC_EOI_ACK);
+}
+
void __cpuinit kvm_guest_cpu_init(void)
{
if (!kvm_para_available())
@@ -300,11 +319,20 @@ void __cpuinit kvm_guest_cpu_init(void)
smp_processor_id());
}
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) {
+ unsigned long pa;
+ /* Size alignment is implied but just to make it explicit. */
+ BUILD_BUG_ON(__alignof__(kvm_apic_eoi) < 4);
+ __get_cpu_var(kvm_apic_eoi) = 0;
+ pa = __pa(&__get_cpu_var(kvm_apic_eoi)) | KVM_MSR_ENABLED;
+ wrmsrl(MSR_KVM_PV_EOI_EN, pa);
+ }
+
if (has_steal_clock)
kvm_register_steal_time();
}
-static void kvm_pv_disable_apf(void *unused)
+static void kvm_pv_disable_apf(void)
{
if (!__get_cpu_var(apf_reason).enabled)
return;
@@ -316,11 +344,23 @@ static void kvm_pv_disable_apf(void *unused)
smp_processor_id());
}
+static void kvm_pv_guest_cpu_reboot(void *unused)
+{
+ /*
+ * We disable PV EOI before we load a new kernel by kexec,
+ * since MSR_KVM_PV_EOI_EN stores a pointer into old kernel's memory.
+ * New kernel can re-enable when it boots.
+ */
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+ wrmsrl(MSR_KVM_PV_EOI_EN, 0);
+ kvm_pv_disable_apf();
+}
+
static int kvm_pv_reboot_notify(struct notifier_block *nb,
unsigned long code, void *unused)
{
if (code == SYS_RESTART)
- on_each_cpu(kvm_pv_disable_apf, NULL, 1);
+ on_each_cpu(kvm_pv_guest_cpu_reboot, NULL, 1);
return NOTIFY_DONE;
}
@@ -371,7 +411,9 @@ static void __cpuinit kvm_guest_cpu_online(void *dummy)
static void kvm_guest_cpu_offline(void *dummy)
{
kvm_disable_steal_time();
- kvm_pv_disable_apf(NULL);
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+ wrmsrl(MSR_KVM_PV_EOI_EN, 0);
+ kvm_pv_disable_apf();
apf_task_wake_all();
}
@@ -424,6 +466,9 @@ void __init kvm_guest_init(void)
pv_time_ops.steal_clock = kvm_steal_clock;
}
+ if (kvm_para_has_feature(KVM_FEATURE_PV_EOI))
+ apic_set_eoi_write(kvm_guest_apic_eoi_write);
+
#ifdef CONFIG_SMP
smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu;
register_cpu_notifier(&kvm_cpu_notifier);
@@ -432,6 +477,19 @@ void __init kvm_guest_init(void)
#endif
}
+static bool __init kvm_detect(void)
+{
+ if (!kvm_para_available())
+ return false;
+ return true;
+}
+
+const struct hypervisor_x86 x86_hyper_kvm __refconst = {
+ .name = "KVM",
+ .detect = kvm_detect,
+};
+EXPORT_SYMBOL_GPL(x86_hyper_kvm);
+
static __init int activate_jump_labels(void)
{
if (has_steal_clock) {