Haswell has two additional LBR from flags for TSX: in_tx and
abort_tx, implemented as a new "v4" version of the LBR format.
Handle those in and adjust the sign extension code to still
correctly extend. The flags are exported similarly in the LBR
record to the existing misprediction flag
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <ak@linux.jf.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1371515812-9646-6-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This avoids some problems with spurious PMIs on Haswell.
Haswell seems to behave more like P4 in this regard. Do
the same thing as the P4 perf handler by unmasking
the NMI only at the end. Shouldn't make any difference
for earlier family 6 cores.
(Tested on Haswell, IvyBridge, Westmere, Saltwell (Atom).)
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <ak@linux.jf.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1371515812-9646-5-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add simple PEBS support for Haswell.
The constraints are similar to SandyBridge with a few new
events.
Reviewed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <ak@linux.jf.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1371515812-9646-4-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Similar to SandyBridge, but has a few new events and two
new counter bits.
There are some new counter flags that need to be prevented
from being set on fixed counters, and allowed to be set
for generic counters.
Also we add support for the counter 2 constraint to handle
all raw events.
(Contains fixes from Stephane Eranian.)
Reviewed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <ak@linux.jf.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1371515812-9646-3-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support for the Haswell extended (fmt2) PEBS format.
It has a superset of the nhm (fmt1) PEBS fields, but has a
longer record so we need to adjust the code paths.
The main advantage is the new "EventingRip" support which
directly gives the instruction, not off-by-one instruction. So
with precise == 2 we use that directly and don't try to use LBRs
and walking basic blocks. This lowers the overhead of using
precise significantly.
Some other features are added in later patches.
Reviewed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Andi Kleen <ak@linux.jf.intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1371515812-9646-2-git-send-email-andi@firstfloor.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Implement a perf PMU to handle IOMMU performance counters and events.
The PMU only supports counting mode (e.g. perf stat). Since the counters
are shared across all cores, the PMU is implemented as "system-wide" mode.
To invoke the AMD IOMMU PMU, issue a perf tool command such as:
./perf stat -a -e amd_iommu/<events>/ <command>
or:
./perf stat -a -e amd_iommu/config=<config-data>,config1=<config1-data>/ <command>
For example:
./perf stat -a -e amd_iommu/mem_trans_total/ <command>
The resulting count will be how many IOMMU total peripheral memory
operations were performed during the command execution window.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1370466709-3212-3-git-send-email-suravee.suthikulpanit@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
intel_pmu_handle_irq() has a warning in it if it does too many
loops. It is a WARN_ONCE(), but the perf_event_print_debug()
call beneath it is unconditional. For the first warning, you get
a nice backtrace and message, but subsequent ones just dump the
PMU state with no leading messages. I doubt this is what was
intended.
This patch will only print the PMU state when paired with the
WARN_ON() text. It effectively open-codes WARN_ONCE()'s
one-time-only logic.
My suspicion is that the code really just wants to make sure we
do not sit in the loop and spit out a warning for every loop
iteration after the 100th. From what I've seen, this is very
unlikely to happen since we also clear the PMU state.
After this patch, instead of seeing the PMU state dumped each
time, you will just see:
[57494.894540] perf_event_intel: clearing PMU state on CPU#129
[57579.539668] perf_event_intel: clearing PMU state on CPU#10
[57587.137762] perf_event_intel: clearing PMU state on CPU#134
[57623.039912] perf_event_intel: clearing PMU state on CPU#114
[57644.559943] perf_event_intel: clearing PMU state on CPU#118
...
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130530174559.0DB049F4@viggo.jf.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
x86_schedule_events() caches event constraints on the stack during
scheduling. Given the number of possible events, this is 512 bytes of
stack; since it can be invoked under schedule() under god-knows-what,
this is causing stack blowouts.
Trade some space usage for stack safety: add a place to cache the
constraint pointer to struct perf_event. For 8 bytes per event (1% of
its size) we can save the giant stack frame.
This shouldn't change any aspect of scheduling whatsoever and while in
theory the locality's a tiny bit worse, I doubt we'll see any
performance impact either.
Tested: `perf stat whatever` does not blow up and produces
results that aren't hugely obviously wrong. I'm not sure how to run
particularly good tests of perf code, but this should not produce any
functional change whatsoever.
Signed-off-by: Andrew Hunter <ahh@google.com>
Reviewed-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1369332423-4400-1-git-send-email-ahh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch fixes broken support of PEBS-LL on SNB-EP/IVB-EP.
For some reason, the LDLAT extra reg definition for snb_ep
showed up as duplicate in the snb table.
This patch moves the definition of LDLAT back into the
snb_ep table.
Thanks to Don Zickus for tracking this one down.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130607212210.GA11849@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Josh reported that his QEMU is a bad hardware emulator and trips a
WARN in the AMD PMU init code. He requested the WARN be turned into a
pr_err() or similar.
While there, rework the code a little.
Reported-by: Josh Boyer <jwboyer@redhat.com>
Acked-by: Robert Richter <rric@kernel.org>
Acked-by: Jacob Shin <jacob.shin@amd.com>
Cc: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20130521110537.GG26912@twins.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch moves commit 7cc23cd to the generic code:
perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL
The check is now implemented in generic code instead of x86 specific
code. That way we do not have to repeat the test in each arch
supporting branch sampling.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/20130521105337.GA2879@quad
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We're trying to use 64 bit masks but the shifts wrap so we can't use the
high 32 bits. I've fixed this by changing several types to unsigned
long long.
This is a static checker fix. The one change which is clearly needed is
"mask = 0xff << (idx * 8);" where the author obviously intended to use
all 64 bits. The other changes are mostly to silence my static checker.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/20130518183452.GA14587@elgon.mountain
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Clearing RF EFLAGS bit for signal handler. The reason is
that this flag is set by debug exception code to prevent
the recursive exception entry.
Leaving it set for signal handler might prevent debug
exception of the signal handler itself.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Originally-Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1367421944-19082-3-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While porting Vince's perf overflow tests I found perf event
breakpoint overflow does not work properly.
I found the x86 RF EFLAG bit not being set when returning
from debug exception after triggering signal handler. Which
is exactly what you get when you set perf breakpoint overflow
SIGIO handler.
This patch and the next two patches fix the underlying bugs.
This patch adds the RF EFLAGS bit to be restored on return from
signal from the original register context before the signal was
entered.
This will prevent the RF flag to disappear when returning
from exception due to the signal handler being executed.
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Originally-Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: Stephane Eranian <eranian@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1367421944-19082-2-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Moorestown
Revert "x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0"
Hotplug
PCI: acpiphp: Re-enumerate devices when host bridge receives Bus Check
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Merge tag 'pci-v3.10-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"Here are some more fixes for v3.10. The Moorestown update broke Intel
Medfield devices, so I reverted it. The acpiphp change fixes a
regression: we broke hotplug notifications to host bridges when we
split acpiphp into the host-bridge related part and the
endpoint-related part.
Moorestown
Revert "x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0"
Hotplug
PCI: acpiphp: Re-enumerate devices when host bridge receives Bus Check"
* tag 'pci-v3.10-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
Revert "x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0"
PCI: acpiphp: Re-enumerate devices when host bridge receives Bus Check
In commit 78d77df715 ("x86-64, init: Do not set NX bits on non-NX
capable hardware") we added the early_pmd_flags that gets the NX bit set
when a CPU supports NX. However, the new variable was marked __initdata,
because the main _use_ of this is in an __init routine.
However, the bit setting happens from secondary_startup_64(), which is
called not only at bootup, but on every secondary CPU start. Including
resuming from STR and at CPU hotplug time. So the value cannot be
__initdata.
Reported-bisected-and-tested-by: Michal Hocko <mhocko@suse.cz>
Cc: stable@vger.kernel.org # v3.9
Acked-by: Peter Anvin <hpa@linux.intel.com>
Cc: Fernando Luis Vázquez Cao <fernando@oss.ntt.co.jp>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull x86 fixes from Thomas Gleixner:
- Fix for a CPU hot-add deadlock in microcode update code
- Fix for idle consolidation fallout
- Documentation update for initial kernel direct mapping
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/mm: Add missing comments for initial kernel direct mapping
x86/microcode: Add local mutex to fix physical CPU hot-add deadlock
x86: Fix idle consolidation fallout
Pull timer fixes from Thomas Gleixner:
- Cure for not using zalloc in the first place, which leads to random
crashes with CPUMASK_OFF_STACK.
- Revert a user space visible change which broke udev
- Add a missing cpu_online early return introduced by the new full
dyntick conversions
- Plug a long standing race in the timer wheel cpu hotplug code.
Sigh...
- Cleanup NOHZ per cpu data on cpu down to prevent stale data on cpu
up.
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Revert ALWAYS_USE_PERSISTENT_CLOCK compile time optimizaitons
timer: Don't reinitialize the cpu base lock during CPU_UP_PREPARE
tick: Don't invoke tick_nohz_stop_sched_tick() if the cpu is offline
tick: Cleanup NOHZ per cpu data on cpu down
tick: Use zalloc_cpumask_var for allocating offstack cpumasks
Kay Sievers noted that the ALWAYS_USE_PERSISTENT_CLOCK config,
which enables some minor compile time optimization to avoid
uncessary code in mostly the suspend/resume path could cause
problems for userland.
In particular, the dependency for RTC_HCTOSYS on
!ALWAYS_USE_PERSISTENT_CLOCK, which avoids setting the time
twice and simplifies suspend/resume, has the side effect
of causing the /sys/class/rtc/rtcN/hctosys flag to always be
zero, and this flag is commonly used by udev to setup the
/dev/rtc symlink to /dev/rtcN, which can cause pain for
older applications.
While the udev rules could use some work to be less fragile,
breaking userland should strongly be avoided. Additionally
the compile time optimizations are fairly minor, and the code
being optimized is likely to be reworked in the future, so
lets revert this change.
Reported-by: Kay Sievers <kay@vrfy.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Cc: stable <stable@vger.kernel.org> #3.9
Cc: Feng Tang <feng.tang@intel.com>
Cc: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Link: http://lkml.kernel.org/r/1366828376-18124-1-git-send-email-john.stultz@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
- More fixes in the vCPU PVHVM hotplug path.
- Add more documentation.
- Fix various ARM related issues in the Xen generic drivers.
- Updates in the xen-pciback driver per Bjorn's updates.
- Mask the x2APIC feature for PV guests.
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Merge tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
- More fixes in the vCPU PVHVM hotplug path.
- Add more documentation.
- Fix various ARM related issues in the Xen generic drivers.
- Updates in the xen-pciback driver per Bjorn's updates.
- Mask the x2APIC feature for PV guests.
* tag 'stable/for-linus-3.10-rc0-tag-two' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pci: Used cached MSI-X capability offset
xen/pci: Use PCI_MSIX_TABLE_BIR, not PCI_MSIX_FLAGS_BIRMASK
xen: clear IRQ_NOAUTOEN and IRQ_NOREQUEST
xen: mask x2APIC feature in PV
xen: SWIOTLB is only used on x86
xen/spinlock: Fix check from greater than to be also be greater or equal to.
xen/smp/pvhvm: Don't point per_cpu(xen_vpcu, 33 and larger) to shared_info
xen/vcpu: Document the xen_vcpu_info and xen_vcpu
xen/vcpu/pvhvm: Fix vcpu hotplugging hanging.
Pull idle update from Len Brown:
"Add support for new Haswell-ULT CPU idle power states"
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
intel_idle: initial C8, C9, C10 support
tools/power turbostat: display C8, C9, C10 residency
Pull stray syscall bits from Al Viro:
"Several syscall-related commits that were missing from the original"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal:
switch compat_sys_sysctl to COMPAT_SYSCALL_DEFINE
unicore32: just use mmap_pgoff()...
unify compat fanotify_mark(2), switch to COMPAT_SYSCALL_DEFINE
x86, vm86: fix VM86 syscalls: use SYSCALL_DEFINEx(...)
Pull kvm fixes from Gleb Natapov:
"Most of the fixes are in the emulator since now we emulate more than
we did before for correctness sake we see more bugs there, but there
is also an OOPS fixed and corruption of xcr0 register."
* tag 'kvm-3.10-2' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: emulator: emulate SALC
KVM: emulator: emulate XLAT
KVM: emulator: emulate AAM
KVM: VMX: fix halt emulation while emulating invalid guest sate
KVM: Fix kvm_irqfd_init initialization
KVM: x86: fix maintenance of guest/host xcr0 state
We now cache the MSI-X capability offset in the struct pci_dev, so no
need to find the capability again.
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
PCI_MSIX_FLAGS_BIRMASK is mis-named because the BIR mask is in the
Table Offset register, not the flags ("Message Control" per spec)
register.
Acked-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Two sets of comments were lost during patch-series shuffling:
- comments for init_range_memory_mapping()
- comments in init_mem_mapping that is helpful for reminding people
that the pagetable is setup top-down
The comments were written by Yinghai in his patch in:
https://lkml.org/lkml/2012/11/28/620
This patch reintroduces them.
Originally-From: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/518BC776.7010506@gmail.com
[ Tidied it all up a bit. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
MSI
PCI: Set ->mask_pos correctly
Hotplug
PCI: Delay final fixups until resources are assigned
Moorestown
x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0
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Merge tag 'pci-v3.10-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
Pull PCI updates from Bjorn Helgaas:
"MSI:
PCI: Set ->mask_pos correctly
Hotplug:
PCI: Delay final fixups until resources are assigned
Moorestown:
x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0"
* tag 'pci-v3.10-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci:
PCI: Delay final fixups until resources are assigned
x86/pci/mrst: Use configuration mechanism 1 for 00:00.0, 00:02.0, 00:03.0
PCI: Set ->mask_pos correctly
GENERIC_GPIO now synonymous with GPIOLIB. There are no longer any valid
cases for enableing GENERIC_GPIO without GPIOLIB, even though it is
possible to do so which has been causing confusion and breakage. This
branch does the work to completely eliminate GENERIC_GPIO.
However, it is not trivial to just create a branch to remove it. Over
the course of the v3.9 cycle more code referencing GENERIC_GPIO has been
added to linux-next that conflicts with this branch. The following must
be done to resolve the conflicts when merging this branch into mainline:
* "git grep CONFIG_GENERIC_GPIO" should return 0 hits. Matches should be
replaced with CONFIG_GPIOLIB
* "git grep '\bGENERIC_GPIO\b'" should return 1 hit in the Chinese
documentation.
* Selectors of GENERIC_GPIO should be turned into selectors of GPIOLIB
* definitions of the option in architecture Kconfig code should be deleted.
Stephen has 3 merge fixup patches[1] that do the above. They are currently
applicable on mainline as of May 2nd.
[1] http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg428056.html
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux
Pull removal of GENERIC_GPIO from Grant Likely:
"GENERIC_GPIO now synonymous with GPIOLIB. There are no longer any
valid cases for enableing GENERIC_GPIO without GPIOLIB, even though it
is possible to do so which has been causing confusion and breakage.
This branch does the work to completely eliminate GENERIC_GPIO."
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux:
gpio: update gpio Chinese documentation
Remove GENERIC_GPIO config option
Convert selectors of GENERIC_GPIO to GPIOLIB
blackfin: force use of gpiolib
m68k: coldfire: use gpiolib
mips: pnx833x: remove requirement for GENERIC_GPIO
openrisc: default GENERIC_GPIO to false
avr32: default GENERIC_GPIO to false
xtensa: remove explicit selection of GENERIC_GPIO
sh: replace CONFIG_GENERIC_GPIO by CONFIG_GPIOLIB
powerpc: remove redundant GENERIC_GPIO selection
unicore32: default GENERIC_GPIO to false
unicore32: remove unneeded select GENERIC_GPIO
arm: plat-orion: use GPIO driver on CONFIG_GPIOLIB
arm: remove redundant GENERIC_GPIO selection
mips: alchemy: require gpiolib
mips: txx9: change GENERIC_GPIO to GPIOLIB
mips: loongson: use GPIO driver on CONFIG_GPIOLIB
mips: remove redundant GENERIC_GPIO select
This is an almost-undocumented instruction available in 32-bit mode.
I say "almost" undocumented because AMD documents it in their opcode
maps just to say that it is unavailable in 64-bit mode (sections
"A.2.1 One-Byte Opcodes" and "B.3 Invalid and Reassigned Instructions
in 64-Bit Mode").
It is roughly equivalent to "sbb %al, %al" except it does not
set the flags. Use fastop to emulate it, but do not use the opcode
directly because it would fail if the host is 64-bit!
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
It is just a MOV in disguise, with a funny source address.
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This is used by SGABIOS, KVM breaks with emulate_invalid_guest_state=1.
AAM needs the source operand to be unsigned; do the same in AAD as well
for consistency, even though it does not affect the result.
Reported-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com>
Cc: stable@vger.kernel.org # 3.9
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
This can easily be triggered if a new CPU is added (via
ACPI hotplug mechanism) and from user-space you do:
echo 1 > /sys/devices/system/cpu/cpu3/online
(or wait for UDEV to do it) on a newly appeared physical CPU.
The deadlock is that the "store_online" in drivers/base/cpu.c
takes the cpu_hotplug_driver_lock() lock, then calls "cpu_up".
"cpu_up" eventually ends up calling "save_mc_for_early"
which also takes the cpu_hotplug_driver_lock() lock.
And here is that lockdep thinks of it:
smpboot: Stack at about ffff880075c39f44
smpboot: CPU3: has booted.
microcode: CPU3 sig=0x206a7, pf=0x2, revision=0x25
=============================================
[ INFO: possible recursive locking detected ]
3.9.0upstream-10129-g167af0e #1 Not tainted
---------------------------------------------
sh/2487 is trying to acquire lock:
(x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
but task is already holding lock:
(x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(x86_cpu_hotplug_driver_mutex);
lock(x86_cpu_hotplug_driver_mutex);
*** DEADLOCK ***
May be due to missing lock nesting notation
6 locks held by sh/2487:
#0: (sb_writers#5){.+.+.+}, at: [<ffffffff811ca48d>] vfs_write+0x17d/0x190
#1: (&buffer->mutex){+.+.+.}, at: [<ffffffff812464ef>] sysfs_write_file+0x3f/0x160
#2: (s_active#20){.+.+.+}, at: [<ffffffff81246578>] sysfs_write_file+0xc8/0x160
#3: (x86_cpu_hotplug_driver_mutex){+.+.+.}, at: [<ffffffff81075512>] cpu_hotplug_driver_lock+0x12/0x20
#4: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff810961c2>] cpu_maps_update_begin+0x12/0x20
#5: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff810962a7>] cpu_hotplug_begin+0x27/0x60
Suggested-and-Acked-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: fenghua.yu@intel.com
Cc: xen-devel@lists.xensource.com
Cc: stable@vger.kernel.org # for v3.9
Link: http://lkml.kernel.org/r/1368029583-23337-1-git-send-email-konrad.wilk@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The invalid guest state emulation loop does not check halt_request
which causes 100% cpu loop while guest is in halt and in invalid
state, but more serious issue is that this leaves halt_request set, so
random instruction emulated by vm86 #GP exit can be interpreted
as halt which causes guest hang. Fix both problems by handling
halt_request in emulation loop.
Reported-by: Tomas Papan <tomas.papan@gmail.com>
Tested-by: Tomas Papan <tomas.papan@gmail.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
CC: stable@vger.kernel.org
Signed-off-by: Gleb Natapov <gleb@redhat.com>
During review of git commit cb9c6f15f3
("xen/spinlock: Check against default value of -1 for IRQ line.")
Stefano pointed out a bug in the patch. Unfortunatly due to vacation
timing the fix was not applied and this patch fixes it up.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
As it will point to some data, but not event channel data (the
shared_info has an array limited to 32).
This means that for PVHVM guests with more than 32 VCPUs without
the usage of VCPUOP_register_info any interrupts to VCPUs
larger than 32 would have gone unnoticed during early bootup.
That is OK, as during early bootup, in smp_init we end up calling
the hotplug mechanism (xen_hvm_cpu_notify) which makes the
VCPUOP_register_vcpu_info call for all VCPUs and we can receive
interrupts on VCPUs 33 and further.
This is just a cleanup.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Emulation of xcr0 writes zero guest_xcr0_loaded variable so that
subsequent VM-entry reloads CPU's xcr0 with guests xcr0 value.
However, this is incorrect because guest_xcr0_loaded variable is
read to decide whether to reload hosts xcr0.
In case the vcpu thread is scheduled out after the guest_xcr0_loaded = 0
assignment, and scheduler decides to preload FPU:
switch_to
{
__switch_to
__math_state_restore
restore_fpu_checking
fpu_restore_checking
if (use_xsave())
fpu_xrstor_checking
xrstor64 with CPU's xcr0 == guests xcr0
Fix by properly restoring hosts xcr0 during emulation of xcr0 writes.
Analyzed-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Merge rwsem optimizations from Michel Lespinasse:
"These patches extend Alex Shi's work (which added write lock stealing
on the rwsem slow path) in order to provide rwsem write lock stealing
on the fast path (that is, without taking the rwsem's wait_lock).
I have unfortunately been unable to push this through -next before due
to Ingo Molnar / David Howells / Peter Zijlstra being busy with other
things. However, this has gotten some attention from Rik van Riel and
Davidlohr Bueso who both commented that they felt this was ready for
v3.10, and Ingo Molnar has said that he was OK with me pushing
directly to you. So, here goes :)
Davidlohr got the following test results from pgbench running on a
quad-core laptop:
| db_size | clients | tps-vanilla | tps-rwsem |
+---------+----------+----------------+--------------+
| 160 MB | 1 | 5803 | 6906 | + 19.0%
| 160 MB | 2 | 13092 | 15931 |
| 160 MB | 4 | 29412 | 33021 |
| 160 MB | 8 | 32448 | 34626 |
| 160 MB | 16 | 32758 | 33098 |
| 160 MB | 20 | 26940 | 31343 | + 16.3%
| 160 MB | 30 | 25147 | 28961 |
| 160 MB | 40 | 25484 | 26902 |
| 160 MB | 50 | 24528 | 25760 |
------------------------------------------------------
| 1.6 GB | 1 | 5733 | 7729 | + 34.8%
| 1.6 GB | 2 | 9411 | 19009 | + 101.9%
| 1.6 GB | 4 | 31818 | 33185 |
| 1.6 GB | 8 | 33700 | 34550 |
| 1.6 GB | 16 | 32751 | 33079 |
| 1.6 GB | 20 | 30919 | 31494 |
| 1.6 GB | 30 | 28540 | 28535 |
| 1.6 GB | 40 | 26380 | 27054 |
| 1.6 GB | 50 | 25241 | 25591 |
------------------------------------------------------
| 7.6 GB | 1 | 5779 | 6224 |
| 7.6 GB | 2 | 10897 | 13611 | + 24.9%
| 7.6 GB | 4 | 32683 | 33108 |
| 7.6 GB | 8 | 33968 | 34712 |
| 7.6 GB | 16 | 32287 | 32895 |
| 7.6 GB | 20 | 27770 | 31689 | + 14.1%
| 7.6 GB | 30 | 26739 | 29003 |
| 7.6 GB | 40 | 24901 | 26683 |
| 7.6 GB | 50 | 17115 | 25925 | + 51.5%
------------------------------------------------------
(Davidlohr also has one additional patch which further improves
throughput, though I will ask him to send it directly to you as I have
suggested some minor changes)."
* emailed patches from Michel Lespinasse <walken@google.com>:
rwsem: no need for explicit signed longs
x86 rwsem: avoid taking slow path when stealing write lock
rwsem: do not block readers at head of queue if other readers are active
rwsem: implement support for write lock stealing on the fastpath
rwsem: simplify __rwsem_do_wake
rwsem: skip initial trylock in rwsem_down_write_failed
rwsem: avoid taking wait_lock in rwsem_down_write_failed
rwsem: use cmpxchg for trying to steal write lock
rwsem: more agressive lock stealing in rwsem_down_write_failed
rwsem: simplify rwsem_down_write_failed
rwsem: simplify rwsem_down_read_failed
rwsem: move rwsem_down_failed_common code into rwsem_down_{read,write}_failed
rwsem: shorter spinlocked section in rwsem_down_failed_common()
rwsem: make the waiter type an enumeration rather than a bitmask
The core code expects the arch idle code to return with interrupts
enabled. The conversion missed two x86 cases which fail to do that.
Reported-and-tested-by: Markus Trippelsdorf <markus@trippelsdorf.de>
Tested-by: Borislav Petkov <bp@alien8.de>
Link: http://lkml.kernel.org/r/alpine.LFD.2.02.1305021557030.3972@ionos
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
modify __down_write[_nested] and __down_write_trylock to grab the write
lock whenever the active count is 0, even if there are queued waiters
(they must be writers pending wakeup, since the active count is 0).
Note that this is an optimization only; architectures without this
optimization will still work fine:
- __down_write() would take the slow path which would take the wait_lock
and then try stealing the lock (as in the spinlocked rwsem implementation)
- __down_write_trylock() would fail, but callers must be ready to deal
with that - since there are some writers pending wakeup, they could
have raced with us and obtained the lock before we steal it.
Signed-off-by: Michel Lespinasse <walken@google.com>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Acked-by: Davidlohr Bueso <davidlohr.bueso@hp.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
They are important structures and it is not clear at first
look what they are for.
The xen_vcpu is a pointer. By default it points to the shared_info
structure (at the CPU offset location). However if the
VCPUOP_register_vcpu_info hypercall is implemented we can make the
xen_vcpu pointer point to a per-CPU location.
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
[v1: Added comments from Ian Campbell]
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
The updates are mostly about the x86 IOMMUs this time. Exceptions are
the groundwork for the PAMU IOMMU from Freescale (for a PPC platform)
and an extension to the IOMMU group interface. On the x86 side this
includes a workaround for VT-d to disable interrupt remapping on broken
chipsets. On the AMD-Vi side the most important new feature is a kernel
command-line interface to override broken information in IVRS ACPI
tables and get interrupt remapping working this way. Besides that there
are small fixes all over the place.
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Merge tag 'iommu-updates-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull IOMMU updates from Joerg Roedel:
"The updates are mostly about the x86 IOMMUs this time.
Exceptions are the groundwork for the PAMU IOMMU from Freescale (for a
PPC platform) and an extension to the IOMMU group interface.
On the x86 side this includes a workaround for VT-d to disable
interrupt remapping on broken chipsets. On the AMD-Vi side the most
important new feature is a kernel command-line interface to override
broken information in IVRS ACPI tables and get interrupt remapping
working this way.
Besides that there are small fixes all over the place."
* tag 'iommu-updates-v3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (24 commits)
iommu/tegra: Fix printk formats for dma_addr_t
iommu: Add a function to find an iommu group by id
iommu/vt-d: Remove warning for HPET scope type
iommu: Move swap_pci_ref function to drivers/iommu/pci.h.
iommu/vt-d: Disable translation if already enabled
iommu/amd: fix error return code in early_amd_iommu_init()
iommu/AMD: Per-thread IOMMU Interrupt Handling
iommu: Include linux/err.h
iommu/amd: Workaround for ERBT1312
iommu/amd: Document ivrs_ioapic and ivrs_hpet parameters
iommu/amd: Don't report firmware bugs with cmd-line ivrs overrides
iommu/amd: Add ioapic and hpet ivrs override
iommu/amd: Add early maps for ioapic and hpet
iommu/amd: Extend IVRS special device data structure
iommu/amd: Move add_special_device() to __init
iommu: Fix compile warnings with forward declarations
iommu/amd: Properly initialize irq-table lock
iommu/amd: Use AMD specific data structure for irq remapping
iommu/amd: Remove map_sg_no_iommu()
iommu/vt-d: add quirk for broken interrupt remapping on 55XX chipsets
...
If a user did:
echo 0 > /sys/devices/system/cpu/cpu1/online
echo 1 > /sys/devices/system/cpu/cpu1/online
we would (this a build with DEBUG enabled) get to:
smpboot: ++++++++++++++++++++=_---CPU UP 1
.. snip..
smpboot: Stack at about ffff880074c0ff44
smpboot: CPU1: has booted.
and hang. The RCU mechanism would kick in an try to IPI the CPU1
but the IPIs (and all other interrupts) would never arrive at the
CPU1. At first glance at least. A bit digging in the hypervisor
trace shows that (using xenanalyze):
[vla] d4v1 vec 243 injecting
0.043163027 --|x d4v1 intr_window vec 243 src 5(vector) intr f3
] 0.043163639 --|x d4v1 vmentry cycles 1468
] 0.043164913 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254
0.043164913 --|x d4v1 inj_virq vec 243 real
[vla] d4v1 vec 243 injecting
0.043164913 --|x d4v1 intr_window vec 243 src 5(vector) intr f3
] 0.043165526 --|x d4v1 vmentry cycles 1472
] 0.043166800 --|x d4v1 vmexit exit_reason PENDING_INTERRUPT eip ffffffff81673254
0.043166800 --|x d4v1 inj_virq vec 243 real
[vla] d4v1 vec 243 injecting
there is a pending event (subsequent debugging shows it is the IPI
from the VCPU0 when smpboot.c on VCPU1 has done
"set_cpu_online(smp_processor_id(), true)") and the guest VCPU1 is
interrupted with the callback IPI (0xf3 aka 243) which ends up calling
__xen_evtchn_do_upcall.
The __xen_evtchn_do_upcall seems to do *something* but not acknowledge
the pending events. And the moment the guest does a 'cli' (that is the
ffffffff81673254 in the log above) the hypervisor is invoked again to
inject the IPI (0xf3) to tell the guest it has pending interrupts.
This repeats itself forever.
The culprit was the per_cpu(xen_vcpu, cpu) pointer. At the bootup
we set each per_cpu(xen_vcpu, cpu) to point to the
shared_info->vcpu_info[vcpu] but later on use the VCPUOP_register_vcpu_info
to register per-CPU structures (xen_vcpu_setup).
This is used to allow events for more than 32 VCPUs and for performance
optimizations reasons.
When the user performs the VCPU hotplug we end up calling the
the xen_vcpu_setup once more. We make the hypercall which returns
-EINVAL as it does not allow multiple registration calls (and
already has re-assigned where the events are being set). We pick
the fallback case and set per_cpu(xen_vcpu, cpu) to point to the
shared_info->vcpu_info[vcpu] (which is a good fallback during bootup).
However the hypervisor is still setting events in the register
per-cpu structure (per_cpu(xen_vcpu_info, cpu)).
As such when the events are set by the hypervisor (such as timer one),
and when we iterate in __xen_evtchn_do_upcall we end up reading stale
events from the shared_info->vcpu_info[vcpu] instead of the
per_cpu(xen_vcpu_info, cpu) structures. Hence we never acknowledge the
events that the hypervisor has set and the hypervisor keeps on reminding
us to ack the events which we never do.
The fix is simple. Don't on the second time when xen_vcpu_setup is
called over-write the per_cpu(xen_vcpu, cpu) if it points to
per_cpu(xen_vcpu_info).
Acked-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
CC: stable@vger.kernel.org
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Pull kvm updates from Gleb Natapov:
"Highlights of the updates are:
general:
- new emulated device API
- legacy device assignment is now optional
- irqfd interface is more generic and can be shared between arches
x86:
- VMCS shadow support and other nested VMX improvements
- APIC virtualization and Posted Interrupt hardware support
- Optimize mmio spte zapping
ppc:
- BookE: in-kernel MPIC emulation with irqfd support
- Book3S: in-kernel XICS emulation (incomplete)
- Book3S: HV: migration fixes
- BookE: more debug support preparation
- BookE: e6500 support
ARM:
- reworking of Hyp idmaps
s390:
- ioeventfd for virtio-ccw
And many other bug fixes, cleanups and improvements"
* tag 'kvm-3.10-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits)
kvm: Add compat_ioctl for device control API
KVM: x86: Account for failing enable_irq_window for NMI window request
KVM: PPC: Book3S: Add API for in-kernel XICS emulation
kvm/ppc/mpic: fix missing unlock in set_base_addr()
kvm/ppc: Hold srcu lock when calling kvm_io_bus_read/write
kvm/ppc/mpic: remove users
kvm/ppc/mpic: fix mmio region lists when multiple guests used
kvm/ppc/mpic: remove default routes from documentation
kvm: KVM_CAP_IOMMU only available with device assignment
ARM: KVM: iterate over all CPUs for CPU compatibility check
KVM: ARM: Fix spelling in error message
ARM: KVM: define KVM_ARM_MAX_VCPUS unconditionally
KVM: ARM: Fix API documentation for ONE_REG encoding
ARM: KVM: promote vfp_host pointer to generic host cpu context
ARM: KVM: add architecture specific hook for capabilities
ARM: KVM: perform HYP initilization for hotplugged CPUs
ARM: KVM: switch to a dual-step HYP init code
ARM: KVM: rework HYP page table freeing
ARM: KVM: enforce maximum size for identity mapped code
ARM: KVM: move to a KVM provided HYP idmap
...
Pull perf fixes from Ingo Molnar:
"Misc fixes plus a small hw-enablement patch for Intel IB model 58
uncore events"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/lbr: Demand proper privileges for PERF_SAMPLE_BRANCH_KERNEL
perf/x86/intel/lbr: Fix LBR filter
perf/x86: Blacklist all MEM_*_RETIRED events for Ivy Bridge
perf: Fix vmalloc ring buffer pages handling
perf/x86/intel: Fix unintended variable name reuse
perf/x86/intel: Add support for IvyBridge model 58 Uncore
perf/x86/intel: Fix typo in perf_event_intel_uncore.c
x86: Eliminate irq_mis_count counted in arch_irq_stat
