linux-stable.git/include/linux/kvm_host.h, branch v3.17.2

KVM: Move more code under CONFIG_HAVE_KVM_IRQFD

2014-08-06T12:24:47+00:00

Commits e4d57e1ee1ab (KVM: Move irq notifier implementation into
eventfd.c, 2014-06-30) included the irq notifier code unconditionally
in eventfd.c, while it was under CONFIG_HAVE_KVM_IRQCHIP before.

Similarly, commit 297e21053a52 (KVM: Give IRQFD its own separate enabling
Kconfig option, 2014-06-30) moved code from CONFIG_HAVE_IRQ_ROUTING
to CONFIG_HAVE_KVM_IRQFD but forgot to move the pieces that used to be
under CONFIG_HAVE_KVM_IRQCHIP.

Together, this broke compilation without CONFIG_KVM_XICS.  Fix by adding
or changing the #ifdefs so that they point at CONFIG_HAVE_KVM_IRQFD.

Signed-off-by: Paolo Bonzini

KVM: Give IRQFD its own separate enabling Kconfig option

2014-08-05T12:26:28+00:00

Currently, the IRQFD code is conditional on CONFIG_HAVE_KVM_IRQ_ROUTING.
So that we can have the IRQFD code compiled in without having the
IRQ routing code, this creates a new CONFIG_HAVE_KVM_IRQFD, makes
the IRQFD code conditional on it instead of CONFIG_HAVE_KVM_IRQ_ROUTING,
and makes all the platforms that currently select HAVE_KVM_IRQ_ROUTING
also select HAVE_KVM_IRQFD.

Signed-off-by: Paul Mackerras 
Tested-by: Eric Auger 
Tested-by: Cornelia Huck 
Signed-off-by: Paolo Bonzini

KVM: Move all accesses to kvm::irq_routing into irqchip.c

2014-08-05T12:26:20+00:00

Now that struct _irqfd does not keep a reference to storage pointed
to by the irq_routing field of struct kvm, we can move the statement
that updates it out from under the irqfds.lock and put it in
kvm_set_irq_routing() instead.  That means we then have to take a
srcu_read_lock on kvm->irq_srcu around the irqfd_update call in
kvm_irqfd_assign(), since holding the kvm->irqfds.lock no longer
ensures that that the routing can't change.

Combined with changing kvm_irq_map_gsi() and kvm_irq_map_chip_pin()
to take a struct kvm * argument instead of the pointer to the routing
table, this allows us to to move all references to kvm->irq_routing
into irqchip.c.  That in turn allows us to move the definition of the
kvm_irq_routing_table struct into irqchip.c as well.

Signed-off-by: Paul Mackerras 
Tested-by: Eric Auger 
Tested-by: Cornelia Huck 
Signed-off-by: Paolo Bonzini

KVM: irqchip: Provide and use accessors for irq routing table

2014-08-05T12:26:16+00:00

This provides accessor functions for the KVM interrupt mappings, in
order to reduce the amount of code that accesses the fields of the
kvm_irq_routing_table struct, and restrict that code to one file,
virt/kvm/irqchip.c.  The new functions are kvm_irq_map_gsi(), which
maps from a global interrupt number to a set of IRQ routing entries,
and kvm_irq_map_chip_pin, which maps from IRQ chip and pin numbers to
a global interrupt number.

This also moves the update of kvm_irq_routing_table::chip[][]
into irqchip.c, out of the various kvm_set_routing_entry
implementations.  That means that none of the kvm_set_routing_entry
implementations need the kvm_irq_routing_table argument anymore,
so this removes it.

This does not change any locking or data lifetime rules.

Signed-off-by: Paul Mackerras 
Tested-by: Eric Auger 
Tested-by: Cornelia Huck 
Signed-off-by: Paolo Bonzini

KVM: Rename and add argument to check_extension

2014-07-28T13:23:17+00:00

In preparation to make the check_extension function available to VM scope
we add a struct kvm * argument to the function header and rename the function
accordingly. It will still be called from the /dev/kvm fd, but with a NULL
argument for struct kvm *.

Signed-off-by: Alexander Graf 
Acked-by: Paolo Bonzini

Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2014-06-13T02:42:15+00:00

Pull more scheduler updates from Ingo Molnar:
 "Second round of scheduler changes:
   - try-to-wakeup and IPI reduction speedups, from Andy Lutomirski
   - continued power scheduling cleanups and refactorings, from Nicolas
     Pitre
   - misc fixes and enhancements"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/deadline: Delete extraneous extern for to_ratio()
  sched/idle: Optimize try-to-wake-up IPI
  sched/idle: Simplify wake_up_idle_cpu()
  sched/idle: Clear polling before descheduling the idle thread
  sched, trace: Add a tracepoint for IPI-less remote wakeups
  cpuidle: Set polling in poll_idle
  sched: Remove redundant assignment to "rt_rq" in update_curr_rt(...)
  sched: Rename capacity related flags
  sched: Final power vs. capacity cleanups
  sched: Remove remaining dubious usage of "power"
  sched: Let 'struct sched_group_power' care about CPU capacity
  sched/fair: Disambiguate existing/remaining "capacity" usage
  sched/fair: Change "has_capacity" to "has_free_capacity"
  sched/fair: Remove "power" from 'struct numa_stats'
  sched: Fix signedness bug in yield_to()
  sched/fair: Use time_after() in record_wakee()
  sched/balancing: Reduce the rate of needless idle load balancing
  sched/fair: Fix unlocked reads of some cfs_b->quota/period

sched: Fix signedness bug in yield_to()

2014-06-05T09:52:13+00:00

yield_to() is supposed to return -ESRCH if there is no task to
yield to, but because the type is bool that is the same as returning
true.

The only place I see which cares is kvm_vcpu_on_spin().

Signed-off-by: Dan Carpenter 
Reviewed-by: Raghavendra 
Signed-off-by: Peter Zijlstra 
Cc: Gleb Natapov 
Cc: Linus Torvalds 
Cc: Paolo Bonzini 
Cc: kvm@vger.kernel.org
Link: http://lkml.kernel.org/r/20140523102042.GA7267@mwanda
Signed-off-by: Ingo Molnar

kvm/irqchip: Speed up KVM_SET_GSI_ROUTING

2014-05-05T14:29:11+00:00

When starting lots of dataplane devices the bootup takes very long on
Christian's s390 with irqfd patches. With larger setups he is even
able to trigger some timeouts in some components.  Turns out that the
KVM_SET_GSI_ROUTING ioctl takes very long (strace claims up to 0.1 sec)
when having multiple CPUs.  This is caused by the  synchronize_rcu and
the HZ=100 of s390.  By changing the code to use a private srcu we can
speed things up.  This patch reduces the boot time till mounting root
from 8 to 2 seconds on my s390 guest with 100 disks.

Uses of hlist_for_each_entry_rcu, hlist_add_head_rcu, hlist_del_init_rcu
are fine because they do not have lockdep checks (hlist_for_each_entry_rcu
uses rcu_dereference_raw rather than rcu_dereference, and write-sides
do not do rcu lockdep at all).

Note that we're hardly relying on the "sleepable" part of srcu.  We just
want SRCU's faster detection of grace periods.

Testing was done by Andrew Theurer using netperf tests STREAM, MAERTS
and RR.  The difference between results "before" and "after" the patch
has mean -0.2% and standard deviation 0.6%.  Using a paired t-test on the
data points says that there is a 2.5% probability that the patch is the
cause of the performance difference (rather than a random fluctuation).

(Restricting the t-test to RR, which is the most likely to be affected,
changes the numbers to respectively -0.3% mean, 0.7% stdev, and 8%
probability that the numbers actually say something about the patch.
The probability increases mostly because there are fewer data points).

Cc: Marcelo Tosatti 
Cc: Michael S. Tsirkin 
Tested-by: Christian Borntraeger  # s390
Reviewed-by: Christian Borntraeger 
Signed-off-by: Christian Borntraeger 
Signed-off-by: Paolo Bonzini

KVM: s390: enable IBS for single running VCPUs

2014-04-29T13:01:54+00:00

This patch enables the IBS facility when a single VCPU is running.
The facility is dynamically turned on/off as soon as other VCPUs
enter/leave the stopped state.

When this facility is operating, some instructions can be executed
faster for single-cpu guests.

Signed-off-by: David Hildenbrand 
Reviewed-by: Dominik Dingel 
Reviewed-by: Cornelia Huck 
Signed-off-by: Christian Borntraeger

Revert "KVM: Simplify kvm->tlbs_dirty handling"

2014-04-23T20:49:48+00:00

This reverts commit 5befdc385ddb2d5ae8995ad89004529a3acf58fc.

Since we will allow flush tlb out of mmu-lock in the later
patch

Signed-off-by: Xiao Guangrong 
Signed-off-by: Marcelo Tosatti