Commit Graph

12955 Commits

Author SHA1 Message Date
Avi Kivity
aa97bb4891 KVM: x86 emulator: implement movdqu instruction (f3 0f 6f, f3 0f 7f)
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:59 -04:00
Avi Kivity
1253791df9 KVM: x86 emulator: SSE support
Add support for marking an instruction as SSE, switching registers used
to the SSE register file.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:59 -04:00
Avi Kivity
0d7cdee83a KVM: x86 emulator: Specialize decoding for insns with 66/f2/f3 prefixes
Most SIMD instructions use the 66/f2/f3 prefixes to distinguish between
different variants of the same instruction.  Usually the encoding is quite
regular, but in some cases (including non-SIMD instructions) the prefixes
generate very different instructions.  Examples include XCHG/PAUSE,
MOVQ/MOVDQA/MOVDQU, and MOVBE/CRC32.

Allow the emulator to handle these special cases by splitting such opcodes
into groups, with different decode flags and execution functions for different
prefixes.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:59 -04:00
Avi Kivity
5037f6f324 KVM: x86 emulator: define callbacks for using the guest fpu within the emulator
Needed for emulating fpu instructions.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
1d6b114f20 KVM: x86 emulator: do not munge rep prefix
Currently we store a rep prefix as 1 or 2 depending on whether it is a REPE or
REPNE.  Since sse instructions depend on the prefix value, store it as the
original opcode to simplify things further on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
cef4dea07f KVM: 16-byte mmio support
Since sse instructions can issue 16-byte mmios, we need to support them.  We
can't increase the kvm_run mmio buffer size to 16 bytes without breaking
compatibility, so instead we break the large mmios into two smaller 8-byte
ones.  Since the bus is 64-bit we aren't breaking any atomicity guarantees.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
5287f194bf KVM: Split mmio completion into a function
Make room for sse mmio completions.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Avi Kivity
70252a1053 KVM: extend in-kernel mmio to handle >8 byte transactions
Needed for coalesced mmio using sse.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:58 -04:00
Gleb Natapov
1499e54af0 KVM: x86: better fix for race between nmi injection and enabling nmi window
Fix race between nmi injection and enabling nmi window in a simpler way.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-05-11 07:56:57 -04:00
Marcelo Tosatti
c761e5868e Revert "KVM: Fix race between nmi injection and enabling nmi window"
This reverts commit f86368493e.

Simpler fix to follow.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2011-05-11 07:56:57 -04:00
Glauber Costa
3291892450 KVM: expose async pf through our standard mechanism
As Avi recently mentioned, the new standard mechanism for exposing features
is KVM_GET_SUPPORTED_CPUID, not spamming CAPs. For some reason async pf
missed that.

So expose async_pf here.

Signed-off-by: Glauber Costa <glommer@redhat.com>
CC: Gleb Natapov <gleb@redhat.com>
CC: Avi Kivity <avi@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:57 -04:00
Avi Kivity
654f06fc65 KVM: VMX: simplify NMI mask management
Use vmx_set_nmi_mask() instead of open-coding management of
the hardware bit and the software hint (nmi_known_unmasked).

There's a slight change of behaviour when running without
hardware virtual NMI support - we now clear the NMI mask if
NMI delivery faulted in that case as well.  This improves
emulation accuracy.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:57 -04:00
Jan Kiszka
89a9fb78b5 KVM: SVM: Remove unused svm_features
We use boot_cpu_has now.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:57 -04:00
Avi Kivity
8878647585 KVM: VMX: Use cached VM_EXIT_INTR_INFO in handle_exception
vmx_complete_atomic_exit() cached it for us, so we can use it here.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
c5ca8e572c KVM: VMX: Don't VMREAD VM_EXIT_INTR_INFO unconditionally
Only read it if we're going to use it later.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
00eba012d5 KVM: VMX: Refactor vmx_complete_atomic_exit()
Move the exit reason checks to the front of the function, for early
exit in the common case.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
f9902069c4 KVM: VMX: Qualify check for host NMI
Check for the exit reason first; this allows us, later,
to avoid a VMREAD for VM_EXIT_INTR_INFO_FIELD.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
9d58b93192 KVM: VMX: Avoid vmx_recover_nmi_blocking() when unneeded
When we haven't injected an interrupt, we don't need to recover
the nmi blocking state (since the guest can't set it by itself).
This allows us to avoid a VMREAD later on.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:56 -04:00
Avi Kivity
69c7302890 KVM: VMX: Cache cpl
We may read the cpl quite often in the same vmexit (instruction privilege
check, memory access checks for instruction and operands), so we gain
a bit if we cache the value.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity
f4c63e5d5a KVM: VMX: Optimize vmx_get_cpl()
In long mode, vm86 mode is disallowed, so we need not check for
it.  Reading rflags.vm may require a VMREAD, so it is expensive.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity
6de12732c4 KVM: VMX: Optimize vmx_get_rflags()
If called several times within the same exit, return cached results.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Avi Kivity
f6e7847589 KVM: Use kvm_get_rflags() and kvm_set_rflags() instead of the raw versions
Some rflags bits are owned by the host, not guest, so we need to use
kvm_get_rflags() to strip those bits away or kvm_set_rflags() to add them
back.

Signed-off-by: Avi Kivity <avi@redhat.com>
2011-05-11 07:56:54 -04:00
Peter Zijlstra
63b6a6758e perf events, x86: Fix Intel Nehalem and Westmere last level cache event definitions
The Intel Nehalem offcore bits implemented in:

  e994d7d23a: perf: Fix LLC-* events on Intel Nehalem/Westmere

... are wrong: they implemented _ACCESS as _HIT and counted OTHER_CORE_HIT* as
MISS even though its clearly documented as an L3 hit ...

Fix them and the Westmere definitions as well.

Cc: Andi Kleen <ak@linux.intel.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1299119690-13991-3-git-send-email-ming.m.lin@intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-06 11:24:48 +02:00
Ingo Molnar
4d70230bb4 Merge branch 'master' of ssh://master.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into perf/urgent 2011-05-06 08:11:28 +02:00
Ingo Molnar
98bb318864 Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/urgent 2011-05-04 20:33:42 +02:00
Linus Torvalds
609cfda586 Merge branch 'stable/bug-fixes-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes-for-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_top
  xen/mmu: Add workaround "x86-64, mm: Put early page table high"
2011-05-03 09:25:42 -07:00
H. Peter Anvin
7806a49ab6 x86, reboot: Fix relocations in reboot_32.S
The use of base for %ebx in this file is arbitrary, *except* that we
also use it to compute the real-mode segment.  Therefore, make it so
that r_base really is the true address to which %ebx points.

This resolves kernel bugzilla 33302.

Reported-and-tested-by: Alexey Zaytsev <alexey.zaytsev@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/n/tip-08os5wi3yq1no0y4i5m4z7he@git.kernel.org
2011-05-02 14:44:46 -07:00
Stefano Stabellini
b9269dc7bf xen: mask_rw_pte mark RO all pagetable pages up to pgt_buf_top
mask_rw_pte is currently checking if a pfn is a pagetable page if it
falls in the range pgt_buf_start - pgt_buf_end but that is incorrect
because pgt_buf_end is a moving target: pgt_buf_top is the real
boundary.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02 16:33:52 -04:00
Konrad Rzeszutek Wilk
a38647837a xen/mmu: Add workaround "x86-64, mm: Put early page table high"
As a consequence of the commit:

commit 4b239f458c
Author: Yinghai Lu <yinghai@kernel.org>
Date:   Fri Dec 17 16:58:28 2010 -0800

    x86-64, mm: Put early page table high

it causes the Linux kernel to crash under Xen:

mapping kernel into physical memory
Xen: setup ISA identity maps
about to get started...
(XEN) mm.c:2466:d0 Bad type (saw 7400000000000001 != exp 1000000000000000) for mfn b1d89 (pfn bacf7)
(XEN) mm.c:3027:d0 Error while pinning mfn b1d89
(XEN) traps.c:481:d0 Unhandled invalid opcode fault/trap [#6] on VCPU 0 [ec=0000]
(XEN) domain_crash_sync called from entry.S
(XEN) Domain 0 (vcpu#0) crashed on cpu#0:
...

The reason is that at some point init_memory_mapping is going to reach
the pagetable pages area and map those pages too (mapping them as normal
memory that falls in the range of addresses passed to init_memory_mapping
as argument). Some of those pages are already pagetable pages (they are
in the range pgt_buf_start-pgt_buf_end) therefore they are going to be
mapped RO and everything is fine.
Some of these pages are not pagetable pages yet (they fall in the range
pgt_buf_end-pgt_buf_top; for example the page at pgt_buf_end) so they
are going to be mapped RW.  When these pages become pagetable pages and
are hooked into the pagetable, xen will find that the guest has already
a RW mapping of them somewhere and fail the operation.
The reason Xen requires pagetables to be RO is that the hypervisor needs
to verify that the pagetables are valid before using them. The validation
operations are called "pinning" (more details in arch/x86/xen/mmu.c).

In order to fix the issue we mark all the pages in the entire range
pgt_buf_start-pgt_buf_top as RO, however when the pagetable allocation
is completed only the range pgt_buf_start-pgt_buf_end is reserved by
init_memory_mapping. Hence the kernel is going to crash as soon as one
of the pages in the range pgt_buf_end-pgt_buf_top is reused (b/c those
ranges are RO).

For this reason, this function is introduced which is called _after_
the init_memory_mapping has completed (in a perfect world we would
call this function from init_memory_mapping, but lets ignore that).

Because we are called _after_ init_memory_mapping the pgt_buf_[start,
end,top] have all changed to new values (b/c another init_memory_mapping
is called). Hence, the first time we enter this function, we save
away the pgt_buf_start value and update the pgt_buf_[end,top].

When we detect that the "old" pgt_buf_start through pgt_buf_end
PFNs have been reserved (so memblock_x86_reserve_range has been called),
we immediately set out to RW the "old" pgt_buf_end through pgt_buf_top.

And then we update those "old" pgt_buf_[end|top] with the new ones
so that we can redo this on the next pagetable.

Acked-by: "H. Peter Anvin" <hpa@zytor.com>
Reviewed-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
[v1: Updated with Jeremy's comments]
[v2: Added the crash output]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-05-02 16:33:34 -04:00
Yinghai Lu
2be19102b7 x86, NUMA: Fix empty memblk detection in numa_cleanup_meminfo()
numa_cleanup_meminfo() trims each memblk between low (0) and
high (max_pfn) limits and discards empty ones.  However, the
emptiness detection incorrectly used equality test.  If the
start of a memblk is higher than max_pfn, it is empty but fails
the equality test and doesn't get discarded.

The condition triggers when max_pfn is lower than start of a
NUMA node and results in memory misconfiguration - leading to
WARN_ON()s and other funnies.  The bug was discovered in devel
branch where 32bit too uses this code path for NUMA init.  If a
node is above the addressing limit, max_pfn ends up lower than
the node triggering this problem.

The failure hasn't been observed on x86-64 but is still possible
with broken hardware e820/NUMA info.  As the fix is very low
risk, it would be better to apply it even for 64bit.

Fix it by using >= instead of ==.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
[ Extracted the actual fix from the original patch and rewrote patch description. ]
Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20110501171204.GO29280@htj.dyndns.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 19:15:11 +02:00
Boris Ostrovsky
e20a2d205c x86, AMD: Fix APIC timer erratum 400 affecting K8 Rev.A-E processors
Older AMD K8 processors (Revisions A-E) are affected by erratum
400 (APIC timer interrupts don't occur in C states greater than
C1). This, for example, means that X86_FEATURE_ARAT flag should
not be set for these parts.

This addresses regression introduced by commit
b87cf80af3 ("x86, AMD: Set ARAT
feature on AMD processors") where the system may become
unresponsive until external interrupt (such as keyboard input)
occurs. This results, for example, in time not being reported
correctly, lack of progress on the system and other lockups.

Reported-by: Joerg-Volker Peetz <jvpeetz@web.de>
Tested-by: Joerg-Volker Peetz <jvpeetz@web.de>
Acked-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: Boris Ostrovsky <Boris.Ostrovsky@amd.com>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1304113663-6586-1-git-send-email-ostr@amd64.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-05-01 18:55:51 +02:00
Linus Torvalds
40a963502c Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  perf, x86, nmi: Move LVT un-masking into irq handlers
  perf events, x86: Work around the Nehalem AAJ80 erratum
  perf, x86: Fix BTS condition
  ftrace: Build without frame pointers on Microblaze
2011-04-29 15:08:53 -07:00
Sebastian Andrzej Siewior
1ff42c32c7 x86: ce4100: Configure IOAPIC pins for USB and SATA to level type
The USB and SATA ioapic interrrupt pins are configured as edge type,
but need to be level type interrupts to work correctly.

[ tglx: Split out from the combo patch ]

Cc: Torben Hohn <torbenh@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/%3C20110427143052.GA15211%40linutronix.de%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-28 11:38:30 +02:00
Sebastian Andrzej Siewior
20443598d9 x86: devicetree: Configure IOAPIC pin only once
We use io_apic_setup_irq_pin() in order to configure pin's interrupt
number polarity and type. This is done on every irq_create_of_mapping()
which happens for instance during pci enable calls. Level typed
interrupts are masked by default, edge are unmasked.

On the first ->xlate() call the level interrupt is configured and
masked. The driver calls request_irq() and the line is unmasked. Lets
assume the interrupt line is shared with another device and we call
pci_enable_device() for this device. The ->xlate() configures the pin
again and it is masked. request_irq() does not unmask the line because
it _is_ already unmasked according to its internal state. So the
interrupt will never be unmasked again.

This patch is based on an earlier work by Torben Hohn and solves the
problem by configuring the pin only once. Since all devices must agree
on the same type and polarity there is no point in configuring the pin
more than once.

[ tglx: Split out the ce4100 part into a separate patch ]

Cc: Torben Hohn <torbenh@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/%3C20110427143052.GA15211%40linutronix.de%3E
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2011-04-28 11:38:30 +02:00
Don Zickus
2bce5daca2 perf, x86, nmi: Move LVT un-masking into irq handlers
It was noticed that P4 machines were generating double NMIs for
each perf event.  These extra NMIs lead to 'Dazed and confused'
messages on the screen.

I tracked this down to a P4 quirk that said the overflow bit had
to be cleared before re-enabling the apic LVT mask.  My first
attempt was to move the un-masking inside the perf nmi handler
from before the chipset NMI handler to after.

This broke Nehalem boxes that seem to like the unmasking before
the counters themselves are re-enabled.

In order to keep this change simple for 2.6.39, I decided to
just simply move the apic LVT un-masking to the beginning of all
the chipset NMI handlers, with the exception of Pentium4's to
fix the double NMI issue.

Later on we can move the un-masking to later in the handlers to
save a number of 'extra' NMIs on those particular chipsets.

I tested this change on a P4 machine, an AMD machine, a Nehalem
box, and a core2quad box.  'perf top' worked correctly along
with various other small 'perf record' runs.  Anything high
stress breaks all the machines but that is a different problem.

Thanks to various people for testing different versions of this
patch.

Reported-and-tested-by: Shaun Ruffell <sruffell@digium.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Link: http://lkml.kernel.org/r/1303900353-10242-1-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
CC: Cyrill Gorcunov <gorcunov@gmail.com>
2011-04-27 17:59:11 +02:00
Ingo Molnar
ec75a71634 perf events, x86: Work around the Nehalem AAJ80 erratum
On Nehalem CPUs the retired branch-misses event can be completely bogus,
when there are no branch-misses occuring. When there are a lot of branch
misses then the count is pretty accurate. Still, this leaves us with an
event that over-counts a lot.

Detect this erratum and work it around by using BR_MISP_EXEC.ANY events.
These will also count speculated branches but still it's a lot more
precise in practice than the architectural event.

Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-yyfg0bxo9jsqxd6a0ovfny27@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 19:34:34 +02:00
Peter Zijlstra
18a073a3ac perf, x86: Fix BTS condition
Currently the x86 backend incorrectly assumes that any BRANCH_INSN
with sample_period==1 is a BTS request. This is not true when we do
frequency driven profiling such as 'perf record -e branches'.

Solves this error:

  $ perf record -e branches ./array
  Error: sys_perf_event_open() syscall returned with 95 (Operation not supported).

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reported-by: Ingo Molnar <mingo@elte.hu>
Cc: "Metzger, Markus T" <markus.t.metzger@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/n/tip-rd2y4ct71hjawzz6fpvsy9hg@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-26 13:34:34 +02:00
H. Peter Anvin
39b68976ac x86, setup: When probing memory with e801, use ax/bx as a pair
When we use BIOS function e801 to probe memory, we should use ax/bx
(or cx/dx) as a pair, not mix and match.  This was a typo during the
translation from assembly code, and breaks at least one set of
machines in the field (which return cx = dx = 0).

Reported-and-tested-by: Chris Samuel <chris@csamuel.org>
Fix-proposed-by: Thomas Meyer <thomas@m3y3r.de>
Link: http://lkml.kernel.org/r/1303566747.12067.10.camel@localhost.localdomain
2011-04-25 14:52:37 -07:00
Frederic Weisbecker
87dc669ba2 x86, hw_breakpoints: Fix racy access to ptrace breakpoints
While the tracer accesses ptrace breakpoints, the child task may
concurrently exit due to a SIGKILL and thus release its breakpoints
at the same time. We can then dereference some freed pointers.

To fix this, hold a reference on the child breakpoints before
manipulating them.

Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Prasad <prasad@linux.vnet.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: v2.6.33.. <stable@kernel.org>
Link: http://lkml.kernel.org/r/1302284067-7860-3-git-send-email-fweisbec@gmail.com
2011-04-25 17:32:40 +02:00
Linus Torvalds
686c4cbb10 Merge branch 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6
* 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/suspend-2.6:
  PM: Add missing syscore_suspend() and syscore_resume() calls
  PM: Fix error code paths executed after failing syscore_suspend()
2011-04-23 22:35:16 -07:00
Peter Zijlstra
f4929bd372 perf, x86: Update/fix Intel Nehalem cache events
Change the Nehalem cache events to use retired memory instruction counters
(similar to Westmere), this greatly improves the provided stats.

Using:

main ()
{
        int i;

        for (i = 0; i < 1000000000; i++) {
                asm("mov (%%rsp), %%rbx;"
                    "mov %%rbx, (%%rsp);" : : : "rbx");
        }
}

We find:

 $ perf stat --repeat 10 -e instructions:u -e l1-dcache-loads:u -e l1-dcache-stores:u ./loop_1b_loads+stores
  Performance counter stats for './loop_1b_loads+stores' (10 runs):
      4,000,081,056 instructions:u           #      0.000 IPC ( +-   0.000% )
      4,999,502,846 l1-dcache-loads:u          ( +-   0.008% )
      1,000,034,832 l1-dcache-stores:u         ( +-   0.000% )
         1.565184942  seconds time elapsed   ( +-   0.005% )

The 5b is surprising - we'd expect 1b:

 $ perf stat --repeat 10 -e instructions:u -e r10b:u -e l1-dcache-stores:u ./loop_1b_loads+stores
  Performance counter stats for './loop_1b_loads+stores' (10 runs):
      4,000,081,054 instructions:u           #      0.000 IPC ( +-   0.000% )
      1,000,021,961 r10b:u                     ( +-   0.000% )
      1,000,030,951 l1-dcache-stores:u         ( +-   0.000% )
         1.565055422  seconds time elapsed   ( +-   0.003% )

Which this patch thus fixes.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Link: http://lkml.kernel.org/n/tip-q9rtru7b7840tws75xzboapv@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 13:50:27 +02:00
Cyrill Gorcunov
1ea5a6afd9 perf, x86: P4 PMU - Don't forget to clear cpuc->active_mask on overflow
It's not enough to simply disable event on overflow the
cpuc->active_mask should be cleared as well otherwise counter
may stall in "active" even in real being already disabled (which
potentially may lead to the situation that user may not use this
counter further).

Don pointed out that:

 " I also noticed this patch fixed some unknown NMIs
   on a P4 when I stressed the box".

Tested-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Link: http://lkml.kernel.org/r/1303398203-2918-3-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 10:21:34 +02:00
Ingo Molnar
b52c55c6a2 x86, perf event: Turn off unstructured raw event access to offcore registers
Andi Kleen pointed out that the Intel offcore support patches were merged
without user-space tool support to the functionality:

 |
 | The offcore_msr perf kernel code was merged into 2.6.39-rc*, but the
 | user space bits were not. This made it impossible to set the extra mask
 | and actually do the OFFCORE profiling
 |

Andi submitted a preliminary patch for user-space support, as an
extension to perf's raw event syntax:

 |
 | Some raw events -- like the Intel OFFCORE events -- support additional
 | parameters. These can be appended after a ':'.
 |
 | For example on a multi socket Intel Nehalem:
 |
 |    perf stat -e r1b7:20ff -a sleep 1
 |
 | Profile the OFFCORE_RESPONSE.ANY_REQUEST with event mask REMOTE_DRAM_0
 | that measures any access to DRAM on another socket.
 |

But this kind of usability is absolutely unacceptable - users should not
be expected to type in magic, CPU and model specific incantations to get
access to useful hardware functionality.

The proper solution is to expose useful offcore functionality via
generalized events - that way users do not have to care which specific
CPU model they are using, they can use the conceptual event and not some
model specific quirky hexa number.

We already have such generalization in place for CPU cache events,
and it's all very extensible.

"Offcore" events measure general DRAM access patters along various
parameters. They are particularly useful in NUMA systems.

We want to support them via generalized DRAM events: either as the
fourth level of cache (after the last-level cache), or as a separate
generalization category.

That way user-space support would be very obvious, memory access
profiling could be done via self-explanatory commands like:

  perf record -e dram ./myapp
  perf record -e dram-remote ./myapp

... to measure DRAM accesses or more expensive cross-node NUMA DRAM
accesses.

These generalized events would work on all CPUs and architectures that
have comparable PMU features.

( Note, these are just examples: actual implementation could have more
  sophistication and more parameter - as long as they center around
  similarly simple usecases. )

Now we do not want to revert *all* of the current offcore bits, as they
are still somewhat useful for generic last-level-cache events, implemented
in this commit:

  e994d7d23a: perf: Fix LLC-* events on Intel Nehalem/Westmere

But we definitely do not yet want to expose the unstructured raw events
to user-space, until better generalization and usability is implemented
for these hardware event features.

( Note: after generalization has been implemented raw offcore events can be
  supported as well: there can always be an odd event that is marginally
  useful but not useful enough to generalize. DRAM profiling is definitely
  *not* such a category so generalization must be done first. )

Furthermore, PERF_TYPE_RAW access to these registers was not intended
to go upstream without proper support - it was a side-effect of the above
e994d7d23a commit, not mentioned in the changelog.

As v2.6.39 is nearing release we go for the simplest approach: disable
the PERF_TYPE_RAW offcore hack for now, before it escapes into a released
kernel and becomes an ABI.

Once proper structure is implemented for these hardware events and users
are offered usable solutions we can revisit this issue.

Reported-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1302658203-4239-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 10:02:53 +02:00
Andi Kleen
b2508e828d perf: Support Xeon E7's via the Westmere PMU driver
There's a new model number public, 47, for Xeon E7 (aka Westmere EX).

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/1303429715-10202-1-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-22 08:27:29 +02:00
David Rientjes
7a6c654782 x86, numa: Fix cpu nodemasks for NUMA emulation and CONFIG_DEBUG_PER_CPU_MAPS
The cpu<->node mappings under CONFIG_DEBUG_PER_CPU_MAPS=y
when NUMA emulation is enabled is currently broken because it does
not iterate through every emulated node and bind cpus that have
affinity to it.

NUMA emulation should bind each cpu to every local node to
accurately represent the true NUMA topology of the underlying
machine.

debug_cpumask_set_cpu() needs to be fixed at the same time so
that the debugging information that it emits shows the new
cpumask of the node being assigned when the cpu is being added
or removed.

It can now take responsibility of setting or clearing the cpu
itself to remove the need for duplicate code.

Also change its last parameter, "enable", to have the correct bool
type since it can only be true or false.

 -v2: Fix the return statements, by Kosaki Motohiro

Acked-and-Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1104201918470.12634@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-21 11:31:00 +02:00
David Rientjes
37f8527dbf Revert "x86, NUMA: Fix fakenuma boot failure"
Andreas Herrmann reported that 7d6b46707f ("x86, NUMA: Fix fakenuma
boot failure") causes certain physical NUMA topologies (for example
AMD Magny-Cours) to move sibling cpus to a single node when in reality
they are in separate domains.

This may result in some nodes being completely void of cpus, which
doesn't accurately represent the correct topology. The system will
boot, but will have suboptimal NUMA performance.

This commit was intended as a fix for NUMA emulation, but should
not cause a regression for real NUMA machines as a side effect.

( There will be a separate fix for the numa-debug code, which
  will not affect physical topologies. )

Reported-by: Andreas Herrmann <herrmann.der.user@googlemail.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1104201918110.12634@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
2011-04-21 11:30:59 +02:00
Linus Torvalds
8653b3f1d5 Merge branch 'stable/bug-fixes-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/bug-fixes-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: mask_rw_pte: do not apply the early_ioremap checks on x86_32
  xen: do not create the extra e820 region at an addr lower than 4G
2011-04-20 17:40:25 -07:00
Stefano Stabellini
ee176455e2 xen: mask_rw_pte: do not apply the early_ioremap checks on x86_32
The two "is_early_ioremap_ptep" checks in mask_rw_pte are only used on
x86_64, in fact early_ioremap is not used at all to setup the initial
pagetable on x86_32.
Moreover on x86_32 the two checks are wrong because the range
pgt_buf_start..pgt_buf_end initially should be mapped RW because
the pages in the range are not pagetable pages yet and haven't been
cleared yet. Afterwards considering the pgt_buf_start..pgt_buf_end is
part of the initial mapping, xen_alloc_pte is capable of turning
the ptes RO when they become pagetable pages.

Fix the issue and improve the readability of the code providing two
different implementation of mask_rw_pte for x86_32 and x86_64.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-20 09:43:13 -04:00
Stefano Stabellini
24bdb0b62c xen: do not create the extra e820 region at an addr lower than 4G
Do not add the extra e820 region at a physical address lower than 4G
because it breaks e820_end_of_low_ram_pfn().

It is OK for us to move the xen_extra_mem_start up and down because this
is the index of the memory that can be ballooned in/out - it is memory
not available to the kernel during bootup.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2011-04-20 09:04:40 -04:00
Rafael J. Wysocki
19234c0819 PM: Add missing syscore_suspend() and syscore_resume() calls
Device suspend/resume infrastructure is used not only by the suspend
and hibernate code in kernel/power, but also by APM, Xen and the
kexec jump feature.  However, commit 40dc166cb5
(PM / Core: Introduce struct syscore_ops for core subsystems PM)
failed to add syscore_suspend() and syscore_resume() calls to that
code, which generally leads to breakage when the features in question
are used.

To fix this problem, add the missing syscore_suspend() and
syscore_resume() calls to arch/x86/kernel/apm_32.c, kernel/kexec.c
and drivers/xen/manage.c.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
2011-04-20 00:36:11 +02:00