Commit Graph

125075 Commits

Author SHA1 Message Date
Hollis Blanchard 7b7015914b KVM: ppc: mostly cosmetic updates to the exit timing accounting code
The only significant changes were to kvmppc_exit_timing_write() and
kvmppc_exit_timing_show(), both of which were dramatically simplified.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:41 +02:00
Hollis Blanchard 73e75b416f KVM: ppc: Implement in-kernel exit timing statistics
Existing KVM statistics are either just counters (kvm_stat) reported for
KVM generally or trace based aproaches like kvm_trace.
For KVM on powerpc we had the need to track the timings of the different exit
types. While this could be achieved parsing data created with a kvm_trace
extension this adds too much overhead (at least on embedded PowerPC) slowing
down the workloads we wanted to measure.

Therefore this patch adds a in-kernel exit timing statistic to the powerpc kvm
code. These statistic is available per vm&vcpu under the kvm debugfs directory.
As this statistic is low, but still some overhead it can be enabled via a
.config entry and should be off by default.

Since this patch touched all powerpc kvm_stat code anyway this code is now
merged and simplified together with the exit timing statistic code (still
working with exit timing disabled in .config).

Signed-off-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:41 +02:00
Hollis Blanchard c5fbdffbda KVM: ppc: save and restore guest mappings on context switch
Store shadow TLB entries in memory, but only use it on host context switch
(instead of every guest entry). This improves performance for most workloads on
440 by reducing the guest TLB miss rate.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:09 +02:00
Hollis Blanchard 7924bd4109 KVM: ppc: directly insert shadow mappings into the hardware TLB
Formerly, we used to maintain a per-vcpu shadow TLB and on every entry to the
guest would load this array into the hardware TLB. This consumed 1280 bytes of
memory (64 entries of 16 bytes plus a struct page pointer each), and also
required some assembly to loop over the array on every entry.

Instead of saving a copy in memory, we can just store shadow mappings directly
into the hardware TLB, accepting that the host kernel will clobber these as
part of the normal 440 TLB round robin. When we do that we need less than half
the memory, and we have decreased the exit handling time for all guest exits,
at the cost of increased number of TLB misses because the host overwrites some
guest entries.

These savings will be increased on processors with larger TLBs or which
implement intelligent flush instructions like tlbivax (which will avoid the
need to walk arrays in software).

In addition to that and to the code simplification, we have a greater chance of
leaving other host userspace mappings in the TLB, instead of forcing all
subsequent tasks to re-fault all their mappings.

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:09 +02:00
Hollis Blanchard c0ca609c5f powerpc/44x: declare tlb_44x_index for use in C code
KVM currently ignores the host's round robin TLB eviction selection, instead
maintaining its own TLB state and its own round robin index. However, by
participating in the normal 44x TLB selection, we can drop the alternate TLB
processing in KVM. This results in a significant performance improvement,
since that processing currently must be done on *every* guest exit.

Accordingly, KVM needs to be able to access and increment tlb_44x_index.
(KVM on 440 cannot be a module, so there is no need to export this symbol.)

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Acked-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:09 +02:00
Hollis Blanchard 891686188f KVM: ppc: support large host pages
KVM on 440 has always been able to handle large guest mappings with 4K host
pages -- we must, since the guest kernel uses 256MB mappings.

This patch makes KVM work when the host has large pages too (tested with 64K).

Signed-off-by: Hollis Blanchard <hollisb@us.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:07 +02:00
Mark McLoughlin 4a643be8c9 KVM: split out kvm_free_assigned_irq()
Split out the logic corresponding to undoing assign_irq() and
clean it up a bit.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:07 +02:00
Mark McLoughlin 61552367b2 KVM: add KVM_USERSPACE_IRQ_SOURCE_ID assertions
Make sure kvm_request_irq_source_id() never returns
KVM_USERSPACE_IRQ_SOURCE_ID.

Likewise, check that kvm_free_irq_source_id() never accepts
KVM_USERSPACE_IRQ_SOURCE_ID.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:07 +02:00
Mark McLoughlin f29b2673d3 KVM: don't free an unallocated irq source id
Set assigned_dev->irq_source_id to -1 so that we can avoid freeing
a source ID which we never allocated.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Mark McLoughlin fdd897e6b5 KVM: make kvm_unregister_irq_ack_notifier() safe
We never pass a NULL notifier pointer here, but we may well
pass a notifier struct which hasn't previously been
registered.

Guard against this by using hlist_del_init() which will
not do anything if the node hasn't been added to the list
and, when removing the node, will ensure that a subsequent
call to hlist_del_init() will be fine too.

Fixes an oops seen when an assigned device is freed before
and IRQ is assigned to it.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Mark McLoughlin 844c7a9ff4 KVM: remove the IRQ ACK notifier assertions
We will obviously never pass a NULL struct kvm_irq_ack_notifier* to
this functions. They are always embedded in the assigned device
structure, so the assertion add nothing.

The irqchip_in_kernel() assertion is very out of place - clearly
this little abstraction needs to know nothing about the upper
layer details.

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Hannes Eder efff9e538f KVM: VMX: fix sparse warning
Impact: make global function static

  arch/x86/kvm/vmx.c:134:3: warning: symbol 'vmx_capability' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:06 +02:00
Hannes Eder e8ba5d311d KVM: fix sparse warning
Impact: make global function static

  virt/kvm/kvm_main.c:85:6: warning: symbol 'kvm_rebooting' was not declared. Should it be static?

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:05 +02:00
Avi Kivity f3fd92fbdb KVM: Remove extraneous semicolon after do/while
Notices by Guillaume Thouvenin.

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:05 +02:00
Avi Kivity 2b48cc75b2 KVM: x86 emulator: fix popf emulation
Set operand type and size to get correct writeback behavior.

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:05 +02:00
Avi Kivity cf5de4f886 KVM: x86 emulator: fix ret emulation
'ret' did not set the operand type or size for the destination, so
writeback ignored it.

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:05 +02:00
Avi Kivity 8a09b6877f KVM: x86 emulator: switch 'pop reg' instruction to emulate_pop()
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:04 +02:00
Avi Kivity 781d0edc5f KVM: x86 emulator: allow pop from mmio
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:04 +02:00
Avi Kivity faa5a3ae39 KVM: x86 emulator: Extract 'pop' sequence into a function
Switch 'pop r/m' instruction to use the new function.

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:04 +02:00
Wu Fengguang b82091824e KVM: Prevent trace call into unloaded module text
Add marker_synchronize_unregister() before module unloading.
This prevents possible trace calls into unloaded module text.

Signed-off-by: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:04 +02:00
Christian Borntraeger 6692cef30b KVM: s390: Fix memory leak of vcpu->run
The s390 backend of kvm never calls kvm_vcpu_uninit. This causes
a memory leak of vcpu->run pages.
Lets call kvm_vcpu_uninit in kvm_arch_vcpu_destroy to free
the vcpu->run.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:03 +02:00
Christian Borntraeger d329c035e7 KVM: s390: Fix refcounting and allow module unload
Currently it is impossible to unload the kvm module on s390.
This patch fixes kvm_arch_destroy_vm to release all cpus.
This make it possible to unload the module.

In addition we stop messing with the module refcount in arch code.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:03 +02:00
Avi Kivity 6b7ad61ffb KVM: x86 emulator: consolidate emulation of two operand instructions
No need to repeat the same assembly block over and over.

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:03 +02:00
Avi Kivity dda96d8f1b KVM: x86 emulator: reduce duplication in one operand emulation thunks
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:03 +02:00
Marcelo Tosatti ecc5589f19 KVM: MMU: optimize set_spte for page sync
The write protect verification in set_spte is unnecessary for page sync.

Its guaranteed that, if the unsync spte was writable, the target page
does not have a write protected shadow (if it had, the spte would have
been write protected under mmu_lock by rmap_write_protect before).

Same reasoning applies to mark_page_dirty: the gfn has been marked as
dirty via the pagefault path.

The cost of hash table and memslot lookups are quite significant if the
workload is pagetable write intensive resulting in increased mmu_lock
contention.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang 5319c66252 KVM: MSI to INTx translate
Now we use MSI as default one, and translate MSI to INTx when guest need
INTx rather than MSI. For legacy device, we provide support for non-sharing
host IRQ.

Provide a parameter msi2intx for this method. The value is true by default in
x86 architecture.

We can't guarantee this mode can work on every device, but for most of us
tested, it works. If your device encounter some trouble with this mode, you can
try set msi2intx modules parameter to 0. If the device is OK with msi2intx=0,
then please report it to KVM mailing list or me. We may prepare a blacklist for
the device that can't work in this mode.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang 6b9cc7fd46 KVM: Enable MSI for device assignment
We enable guest MSI and host MSI support in this patch. The userspace want to
enable MSI should set KVM_DEV_IRQ_ASSIGN_ENABLE_MSI in the assigned_irq's flag.
Function would return -ENOTTY if can't enable MSI, userspace shouldn't set MSI
Enable bit when KVM_ASSIGN_IRQ return -ENOTTY with
KVM_DEV_IRQ_ASSIGN_ENABLE_MSI.

Userspace can tell the support of MSI device from #ifdef KVM_CAP_DEVICE_MSI.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang f64769eb05 KVM: Add assigned_device_msi_dispatch()
The function is used to dispatch MSI to lapic according to MSI message
address and message data.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:02 +02:00
Sheng Yang 68b76f5167 KVM: Export ioapic_get_delivery_bitmask
It would be used for MSI in device assignment, for MSI dispatch.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang 0937c48d07 KVM: Add fields for MSI device assignment
Prepared for kvm_arch_assigned_device_msi_dispatch().

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang fbac7818d8 KVM: Clean up assigned_device_update_irq
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang 4f906c19ae KVM: Replace irq_requested with more generic irq_requested_type
Separate guest irq type and host irq type, for we can support guest using INTx
with host using MSI (but not opposite combination).

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:01 +02:00
Sheng Yang 00e3ed39e2 KVM: Separate update irq to a single function
Separate INTx enabling part to a independence function, so that we can add MSI
enabling part easily.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:00 +02:00
Sheng Yang 342ffb9300 KVM: Move ack notifier register and IRQ sourcd ID request
Distinguish common part for device assignment and INTx part, perparing for
refactor later.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:00 +02:00
Glauber Costa 423cd25a5a x86: KVM guest: sign kvmclock as paravirt
Currently, we only set the KVM paravirt signature in case
of CONFIG_KVM_GUEST. However, it is possible to have it turned
off, while CONFIG_KVM_CLOCK is turned on. This is also a paravirt
case, and should be shown accordingly.

Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:00 +02:00
Avi Kivity df203ec9a7 KVM: VMX: Conditionally request interrupt window after injecting irq
If we're injecting an interrupt, and another one is pending, request
an interrupt window notification so we don't have excess latency on the
second interrupt.

This shouldn't happen in practice since an EOI will be issued, giving a second
chance to request an interrupt window, but...

Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:55:00 +02:00
Xiantao Zhang 8fe0736763 KVM: ia64: Clean up vmm_ivt.S using tab to indent every line
Using tab for indentation for vmm_ivt.S.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:54:59 +02:00
Xiantao Zhang 9f7d5bb5e2 KVM: ia64: Add handler for crashed vmm
Since vmm runs in an isolated address space and it is just a copy
of host's kvm-intel module, so once vmm crashes, we just crash all guests
running on it instead of crashing whole kernel.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:54:59 +02:00
Xiantao Zhang 5e2be19832 KVM: ia64: Add some debug points to provide crash infomation
Use printk infrastructure to print out some debug info once VM crashes.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:54:59 +02:00
Xiantao Zhang 7d63797815 KVM: ia64: Define printk function for kvm-intel module
kvm-intel module is relocated to an isolated address space
with kernel, so it can't call host kernel's printk for debug
purpose. In the module, we implement the printk to output debug
info of vmm.

Signed-off-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:54:59 +02:00
Eduardo Habkost d176720d34 x86: disable VMX on all CPUs on reboot
On emergency_restart, we may need to use an NMI to disable virtualization
on all CPUs. We do that using nmi_shootdown_cpus() if VMX is enabled.

Note: With this patch, we will run the NMI stuff only when the CPU where
emergency_restart() was called has VMX enabled. This should work on most
cases because KVM enables VMX on all CPUs, but we may miss the small
window where KVM is doing that. Also, I don't know if all code using
VMX out there always enable VMX on all CPUs like KVM does. We have two
other alternatives for that:

a) Have an API that all code that enables VMX on any CPU should use
   to tell the kernel core that it is going to enable VMX on the CPUs.
b) Always call nmi_shootdown_cpus() if the CPU supports VMX. This is
   a bit intrusive and more risky, as it would run nmi_shootdown_cpus()
   on emergency_reboot() even on systems where virtualization is never
   enabled.

Finding a proper point to hook the nmi_shootdown_cpus() call isn't
trivial, as the non-emergency machine_restart() (that doesn't need the
NMI tricks) uses machine_emergency_restart() directly.

The solution to make this work without adding a new function or argument
to machine_ops was setting a 'reboot_emergency' flag that tells if
native_machine_emergency_restart() needs to do the virt cleanup or not.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:54:58 +02:00
Eduardo Habkost 2340b62f77 kdump: forcibly disable VMX and SVM on machine_crash_shutdown()
We need to disable virtualization extensions on all CPUs before booting
the kdump kernel, otherwise the kdump kernel booting will fail, and
rebooting after the kdump kernel did its task may also fail.

We do it using cpu_emergency_vmxoff() and cpu_emergency_svm_disable(),
that should always work, because those functions check if the CPUs
support SVM or VMX before doing their tasks.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:30 +02:00
Eduardo Habkost 0f3e9eeba0 x86: cpu_emergency_svm_disable() function
This function can be used by the reboot or kdump code to forcibly
disable SVM on the CPU.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:30 +02:00
Eduardo Habkost 2c8dceebb2 KVM: SVM: move svm_hardware_disable() code to asm/virtext.h
Create cpu_svm_disable() function.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:30 +02:00
Eduardo Habkost 63d1142f8f KVM: SVM: move has_svm() code to asm/virtext.h
Use a trick to keep the printk()s on has_svm() working as before. gcc
will take care of not generating code for the 'msg' stuff when the
function is called with a NULL msg argument.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:29 +02:00
Eduardo Habkost 6aa07a0d77 x86: cpu_emergency_vmxoff() function
Add cpu_emergency_vmxoff() and its friends: cpu_vmx_enabled() and
__cpu_emergency_vmxoff().

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:29 +02:00
Eduardo Habkost 710ff4a855 KVM: VMX: extract kvm_cpu_vmxoff() from hardware_disable()
Along with some comments on why it is different from the core cpu_vmxoff()
function.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:29 +02:00
Eduardo Habkost 1e9931146c x86: asm/virtext.h: add cpu_vmxoff() inline function
Unfortunately we can't use exactly the same code from vmx
hardware_disable(), because the KVM function uses the
__kvm_handle_fault_on_reboot() tricks.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:29 +02:00
Eduardo Habkost 6210e37b12 KVM: VMX: move cpu_has_kvm_support() to an inline on asm/virtext.h
It will be used by core code on kdump and reboot, to disable
vmx if needed.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:28 +02:00
Eduardo Habkost eca70fc567 KVM: VMX: move ASM_VMX_* definitions from asm/kvm_host.h to asm/vmx.h
Those definitions will be used by code outside KVM, so move it outside
of a KVM-specific source file.

Those definitions are used only on kvm/vmx.c, that already includes
asm/vmx.h, so they can be moved safely.

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2008-12-31 16:52:28 +02:00