linux.git/virt, branch v4.3-rc1

Merge branch 'akpm' (patches from Andrew)

2015-09-11T01:19:42+00:00

Merge third patch-bomb from Andrew Morton:

 - even more of the rest of MM

 - lib/ updates

 - checkpatch updates

 - small changes to a few scruffy filesystems

 - kmod fixes/cleanups

 - kexec updates

 - a dma-mapping cleanup series from hch

* emailed patches from Andrew Morton : (81 commits)
  dma-mapping: consolidate dma_set_mask
  dma-mapping: consolidate dma_supported
  dma-mapping: cosolidate dma_mapping_error
  dma-mapping: consolidate dma_{alloc,free}_noncoherent
  dma-mapping: consolidate dma_{alloc,free}_{attrs,coherent}
  mm: use vma_is_anonymous() in create_huge_pmd() and wp_huge_pmd()
  mm: make sure all file VMAs have ->vm_ops set
  mm, mpx: add "vm_flags_t vm_flags" arg to do_mmap_pgoff()
  mm: mark most vm_operations_struct const
  namei: fix warning while make xmldocs caused by namei.c
  ipc: convert invalid scenarios to use WARN_ON
  zlib_deflate/deftree: remove bi_reverse()
  lib/decompress_unlzma: Do a NULL check for pointer
  lib/decompressors: use real out buf size for gunzip with kernel
  fs/affs: make root lookup from blkdev logical size
  sysctl: fix int -> unsigned long assignments in INT_MIN case
  kexec: export KERNEL_IMAGE_SIZE to vmcoreinfo
  kexec: align crash_notes allocation to make it be inside one physical page
  kexec: remove unnecessary test in kimage_alloc_crash_control_pages()
  kexec: split kexec_load syscall from kexec core code
  ...

mmu-notifier: add clear_young callback

2015-09-10T20:29:01+00:00

In the scope of the idle memory tracking feature, which is introduced by
the following patch, we need to clear the referenced/accessed bit not only
in primary, but also in secondary ptes.  The latter is required in order
to estimate wss of KVM VMs.  At the same time we want to avoid flushing
tlb, because it is quite expensive and it won't really affect the final
result.

Currently, there is no function for clearing pte young bit that would meet
our requirements, so this patch introduces one.  To achieve that we have
to add a new mmu-notifier callback, clear_young, since there is no method
for testing-and-clearing a secondary pte w/o flushing tlb.  The new method
is not mandatory and currently only implemented by KVM.

Signed-off-by: Vladimir Davydov 
Reviewed-by: Andres Lagar-Cavilla 
Acked-by: Paolo Bonzini 
Cc: Minchan Kim 
Cc: Raghavendra K T 
Cc: Johannes Weiner 
Cc: Michal Hocko 
Cc: Greg Thelen 
Cc: Michel Lespinasse 
Cc: David Rientjes 
Cc: Pavel Emelyanov 
Cc: Cyrill Gorcunov 
Cc: Jonathan Corbet 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kvm: irqchip: fix memory leak

2015-09-08T09:16:41+00:00

We were taking the exit path after checking ue->flags and return value
of setup_routing_entry(), but 'e' was not freed incase of a failure.

Signed-off-by: Sudip Mukherjee 
Signed-off-by: Paolo Bonzini

KVM: trace kvm_halt_poll_ns grow/shrink

2015-09-06T14:33:14+00:00

Tracepoint for dynamic halt_pool_ns, fired on every potential change.

Signed-off-by: Wanpeng Li 
Signed-off-by: Paolo Bonzini

KVM: dynamic halt-polling

2015-09-06T14:32:43+00:00

There is a downside of always-poll since poll is still happened for idle
vCPUs which can waste cpu usage. This patchset add the ability to adjust
halt_poll_ns dynamically, to grow halt_poll_ns when shot halt is detected,
and to shrink halt_poll_ns when long halt is detected.

There are two new kernel parameters for changing the halt_poll_ns:
halt_poll_ns_grow and halt_poll_ns_shrink.

                        no-poll      always-poll    dynamic-poll
-----------------------------------------------------------------------
Idle (nohz) vCPU %c0     0.15%        0.3%            0.2%
Idle (250HZ) vCPU %c0    1.1%         4.6%~14%        1.2%
TCP_RR latency           34us         27us            26.7us

"Idle (X) vCPU %c0" is the percent of time the physical cpu spent in
c0 over 60 seconds (each vCPU is pinned to a pCPU). (nohz) means the
guest was tickless. (250HZ) means the guest was ticking at 250HZ.

The big win is with ticking operating systems. Running the linux guest
with nohz=off (and HZ=250), we save 3.4%~12.8% CPUs/second and get close
to no-polling overhead levels by using the dynamic-poll. The savings
should be even higher for higher frequency ticks.

Suggested-by: David Matlack 
Signed-off-by: Wanpeng Li 
[Simplify the patch. - Paolo]
Signed-off-by: Paolo Bonzini

KVM: make halt_poll_ns per-vCPU

2015-09-06T14:27:10+00:00

Change halt_poll_ns into per-VCPU variable, seeded from module parameter,
to allow greater flexibility.

Signed-off-by: Wanpeng Li 
Signed-off-by: Paolo Bonzini

Merge tag 'signed-kvm-ppc-next' of git://github.com/agraf/linux-2.6 into kvm-queue

2015-08-22T21:57:59+00:00

Patch queue for ppc - 2015-08-22

Highlights for KVM PPC this time around:

  - Book3S: A few bug fixes
  - Book3S: Allow micro-threading on POWER8

KVM: arm/arm64: timer: Allow the timer to control the active state

2015-08-12T10:28:26+00:00

In order to remove the crude hack where we sneak the masked bit
into the timer's control register, make use of the phys_irq_map
API control the active state of the interrupt.

This causes some limited changes to allow for potential error
propagation.

Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier

KVM: arm/arm64: vgic: Prevent userspace injection of a mapped interrupt

2015-08-12T10:28:26+00:00

Virtual interrupts mapped to a HW interrupt should only be triggered
from inside the kernel. Otherwise, you could end up confusing the
kernel (and the GIC's) state machine.

Rearrange the injection path so that kvm_vgic_inject_irq is
used for non-mapped interrupts, and kvm_vgic_inject_mapped_irq is
used for mapped interrupts. The latter should only be called from
inside the kernel (timer, irqfd).

Reviewed-by: Christoffer Dall 
Signed-off-by: Marc Zyngier

KVM: arm/arm64: vgic: Add vgic_{get,set}_phys_irq_active

2015-08-12T10:28:26+00:00

In order to control the active state of an interrupt, introduce
a pair of accessors allowing the state to be set/queried.

This only affects the logical state, and the HW state will only be
applied at world-switch time.

Acked-by: Christoffer Dall 
Signed-off-by: Marc Zyngier