Commit Graph

25 Commits

Author SHA1 Message Date
Gleb Natapov
1e08ec4a13 KVM: optimize apic interrupt delivery
Most interrupt are delivered to only one vcpu. Use pre-build tables to
find interrupt destination instead of looping through all vcpus. In case
of logical mode loop only through vcpus in a logical cluster irq is sent
to.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-09-20 15:05:26 +03:00
Gleb Natapov
64eb062029 KVM: correctly detect APIC SW state in kvm_apic_post_state_restore()
For apic_set_spiv() to track APIC SW state correctly it needs to see
previous and next values of the spurious vector register, but currently
memset() overwrite the old value before apic_set_spiv() get a chance to
do tracking. Fix it by calling apic_set_spiv() before overwriting old
value.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-09 12:44:46 +03:00
Gleb Natapov
c48f14966c KVM: inline kvm_apic_present() and kvm_lapic_enabled()
Those functions are used during interrupt injection. When inlined they
become nops on the fast path.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-06 19:00:45 +03:00
Gleb Natapov
c5cc421ba3 KVM: use jump label to optimize checking for HW enabled APIC in APIC_BASE MSR
Usually all APICs are HW enabled so the check can be optimized out.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-08-06 19:00:43 +03:00
Avi Kivity
2a6eac9638 KVM: Simplify kvm_timer
'reinject' is never initialized
't_ops' only serves as indirection to lapic_is_periodic; call that directly
   instead
'kvm' is never used
'vcpu' can be derived via container_of

Remove these fields.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01 00:21:06 -03:00
Avi Kivity
e9d90d472d KVM: Remove internal timer abstraction
kvm_timer_fn(), the sole inhabitant of timer.c, is only used by lapic.c. Move
it there to make it easier to hack on it.

struct kvm_timer is a thin wrapper around hrtimer, and only adds obfuscation.
Move near its two users (with different names) to prepare for simplification.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2012-08-01 00:21:06 -03:00
Michael S. Tsirkin
ae7a2a3fb6 KVM: host side for eoi optimization
Implementation of PV EOI using shared memory.
This reduces the number of exits an interrupt
causes as much as by half.

The idea is simple: there's a bit, per APIC, in guest memory,
that tells the guest that it does not need EOI.
We set it before injecting an interrupt and clear
before injecting a nested one. Guest tests it using
a test and clear operation - this is necessary
so that host can detect interrupt nesting -
and if set, it can skip the EOI MSR.

There's a new MSR to set the address of said register
in guest memory. Otherwise not much changed:
- Guest EOI is not required
- Register is tested & ISR is automatically cleared on exit

For testing results see description of previous patch
'kvm_para: guest side for eoi avoidance'.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-06-25 12:40:55 +03:00
Michael S. Tsirkin
8680b94b0e KVM: optimize ISR lookups
We perform ISR lookups twice: during interrupt
injection and on EOI. Typical workloads only have
a single bit set there. So we can avoid ISR scans by
1. counting bits as we set/clear them in ISR
2. on set, caching the injected vector number
3. on clear, invalidating the cache

The real purpose of this is enabling PV EOI
which needs to quickly validate the vector.
But non PV guests also benefit: with this patch,
and without interrupt nesting, apic_find_highest_isr
will always return immediately without scanning ISR.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-06-25 12:37:21 +03:00
Michael S. Tsirkin
5eadf916df KVM: document lapic regs field
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2012-06-25 12:37:14 +03:00
Avi Kivity
8934208221 KVM: Expose kvm_lapic_local_deliver()
Needed to deliver performance monitoring interrupts.

Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-12-27 11:23:39 +02:00
Liu, Jinsong
a3e06bbe84 KVM: emulate lapic tsc deadline timer for guest
This patch emulate lapic tsc deadline timer for guest:
Enumerate tsc deadline timer capability by CPUID;
Enable tsc deadline timer mode by lapic MMIO;
Start tsc deadline timer by WRMSR;

[jan: use do_div()]
[avi: fix for !irqchip_in_kernel()]
[marcelo: another fix for !irqchip_in_kernel()]

Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-10-05 15:34:56 +02:00
Kevin Tian
58fbbf26eb KVM: APIC: avoid instruction emulation for EOI writes
Instruction emulation for EOI writes can be skipped, since sane
guest simply uses MOV instead of string operations. This is a nice
improvement when guest doesn't support x2apic or hyper-V EOI
support.

a single VM bandwidth is observed with ~8% bandwidth improvement
(7.4Gbps->8Gbps), by saving ~5% cycles from EOI emulation.

Signed-off-by: Kevin Tian <kevin.tian@intel.com>
<Based on earlier work from>:
Signed-off-by: Eddie Dong <eddie.dong@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-09-25 19:52:17 +03:00
Takuya Yoshikawa
afc20184b7 KVM: x86: Remove useless regs_page pointer from kvm_lapic
Access to this page is mostly done through the regs member which holds
the address to this page.  The exceptions are in vmx_vcpu_reset() and
kvm_free_lapic() and these both can easily be converted to using regs.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-03-17 13:08:33 -03:00
Gleb Natapov
10388a0716 KVM: Add HYPER-V apic access MSRs
Implement HYPER-V apic MSRs. Spec defines three MSRs that speed-up
access to EOI/TPR/ICR apic registers for PV guests.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Vadim Rozenfeld <vrozenfe@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2010-03-01 12:36:00 -03:00
Gleb Natapov
0105d1a526 KVM: x2apic interface to lapic
This patch implements MSR interface to local apic as defines by x2apic
Intel specification.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:08 +03:00
Gleb Natapov
fc61b800f9 KVM: Add Directed EOI support to APIC emulation
Directed EOI is specified by x2APIC, but is available even when lapic is
in xAPIC mode.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:33:07 +03:00
Gleb Natapov
33e4c68656 KVM: Optimize searching for highest IRR
Most of the time IRR is empty, so instead of scanning the whole IRR on
each VM entry keep a variable that tells us if IRR is not empty. IRR
will have to be scanned twice on each IRQ delivery, but this is much
more rare than VM entry.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10 08:32:57 +03:00
Gleb Natapov
58c2dde17d KVM: APIC: get rid of deliver_bitmask
Deliver interrupt during destination matching loop.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:27 +03:00
Gleb Natapov
343f94fe4d KVM: consolidate ioapic/ipi interrupt delivery logic
Use kvm_apic_match_dest() in kvm_get_intr_delivery_bitmask() instead
of duplicating the same code. Use kvm_get_intr_delivery_bitmask() in
apic_send_ipi() to figure out ipi destination instead of reimplementing
the logic.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:27 +03:00
Gleb Natapov
6da7e3f643 KVM: APIC: kvm_apic_set_irq deliver all kinds of interrupts
Get rid of ioapic_inj_irq() and ioapic_inj_nmi() functions.

Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-06-10 11:48:26 +03:00
Marcelo Tosatti
d3c7b77d1a KVM: unify part of generic timer handling
Hide the internals of vcpu awakening / injection from the in-kernel
emulated timers. This makes future changes in this logic easier and
decreases the distance to more generic timer handling.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-06-10 11:48:25 +03:00
Marcelo Tosatti
b682b814e3 KVM: x86: fix LAPIC pending count calculation
Simplify LAPIC TMCCT calculation by using hrtimer provided
function to query remaining time until expiration.

Fixes host hang with nested ESX.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-02-15 02:47:38 +02:00
Harvey Harrison
8b2cf73cc1 KVM: add statics were possible, function definition in lapic.h
Noticed by sparse:
arch/x86/kvm/vmx.c:1583:6: warning: symbol 'vmx_disable_intercept_for_msr' was not declared. Should it be static?
arch/x86/kvm/x86.c:3406:5: warning: symbol 'kvm_task_switch_16' was not declared. Should it be static?
arch/x86/kvm/x86.c:3429:5: warning: symbol 'kvm_task_switch_32' was not declared. Should it be static?
arch/x86/kvm/mmu.c:1968:6: warning: symbol 'kvm_mmu_remove_one_alloc_mmu_page' was not declared. Should it be static?
arch/x86/kvm/mmu.c:2014:6: warning: symbol 'mmu_destroy_caches' was not declared. Should it be static?
arch/x86/kvm/lapic.c:862:5: warning: symbol 'kvm_lapic_get_base' was not declared. Should it be static?
arch/x86/kvm/i8254.c:94:5: warning: symbol 'pit_get_gate' was not declared. Should it be static?
arch/x86/kvm/i8254.c:196:5: warning: symbol '__pit_timer_fn' was not declared. Should it be static?
arch/x86/kvm/i8254.c:561:6: warning: symbol '__inject_pit_timer_intr' was not declared. Should it be static?

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-07-20 12:40:46 +03:00
Avi Kivity
b93463aa59 KVM: Accelerated apic support
This adds a mechanism for exposing the virtual apic tpr to the guest, and a
protocol for letting the guest update the tpr without causing a vmexit if
conditions allow (e.g. there is no interrupt pending with a higher priority
than the new tpr).

Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:20 +02:00
Zhang Xiantao
82470196fa KVM: Move irqchip declarations into new ioapic.h and lapic.h
This allows reuse of ioapic in ia64.

Signed-off-by: Zhang Xiantao <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
2008-01-30 18:01:19 +02:00