This factors out the AMD native MMCONFIG discovery so we can use it
outside amd_bus.c.
amd_bus.c reads AMD MSRs so it can remove the MMCONFIG area from the
PCI resources. We may also need the MMCONFIG information to work
around BIOS defects in the ACPI MCFG table.
Cc: Borislav Petkov <borislav.petkov@amd.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: stable@kernel.org # 2.6.34+
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
x86 has two kinds of PCI root bus scanning:
(1) ACPI-based, using _CRS resources. This used pci_create_bus(), not
pci_scan_bus(), because ACPI hotplug needed to split the
pci_bus_add_devices() into a separate host bridge .start() method.
This patch parses the _CRS resources earlier, so we can build a list of
resources and pass it to pci_create_root_bus().
Note that as before, we parse the _CRS even if we aren't going to use
it so we can print it for debugging purposes.
(2) All other, which used either default resources (ioport_resource and
iomem_resource) or information read from the hardware via amd_bus.c or
similar. This used pci_scan_bus().
This patch converts x86_pci_root_bus_res_quirks() (previously called
from pcibios_fixup_bus()) to x86_pci_root_bus_resources(), which builds
a list of resources before we call pci_scan_root_bus().
We also use x86_pci_root_bus_resources() if we have ACPI but are
ignoring _CRS.
CC: Yinghai Lu <yinghai.lu@oracle.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
The 'latency timer' of PCI devices, both Type 0 and Type 1,
is setup in architecture-specific code [see: 'pcibios_set_master()'].
There are two approaches being taken by all the architectures - check
if the 'latency timer' is currently set between 16 and 255 and if not
bring it within bounds, or, do nothing (and then there is the
gratuitously different PA-RISC implementation).
There is nothing architecture-specific about PCI's 'latency timer' so
this patch pulls its setup functionality up into the PCI core by
creating a generic 'pcibios_set_master()' function using the '__weak'
attribute which can be used by all architectures as a default which,
if necessary, can then be over-ridden by architecture-specific code.
No functional change.
Signed-off-by: Myron Stowe <myron.stowe@redhat.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
This resolves the conflict in the arch/arm/mach-s3c64xx/s3c6400.c file,
and it fixes the build error in the arch/x86/kernel/microcode_core.c
file, that the merge did not catch.
The microcode_core.c patch was provided by Stephen Rothwell
<sfr@canb.auug.org.au> who was invaluable in the merge issues involved
with the large sysdev removal process in the driver-core tree.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (40 commits)
sched/tracing: Add a new tracepoint for sleeptime
sched: Disable scheduler warnings during oopses
sched: Fix cgroup movement of waking process
sched: Fix cgroup movement of newly created process
sched: Fix cgroup movement of forking process
sched: Remove cfs bandwidth period check in tg_set_cfs_period()
sched: Fix load-balance lock-breaking
sched: Replace all_pinned with a generic flags field
sched: Only queue remote wakeups when crossing cache boundaries
sched: Add missing rcu_dereference() around ->real_parent usage
[S390] fix cputime overflow in uptime_proc_show
[S390] cputime: add sparse checking and cleanup
sched: Mark parent and real_parent as __rcu
sched, nohz: Fix missing RCU read lock
sched, nohz: Set the NOHZ_BALANCE_KICK flag for idle load balancer
sched, nohz: Fix the idle cpu check in nohz_idle_balance
sched: Use jump_labels for sched_feat
sched/accounting: Fix parameter passing in task_group_account_field
sched/accounting: Fix user/system tick double accounting
sched/accounting: Re-use scheduler statistics for the root cgroup
...
Fix up conflicts in
- arch/ia64/include/asm/cputime.h, include/asm-generic/cputime.h
usecs_to_cputime64() vs the sparse cleanups
- kernel/sched/fair.c, kernel/time/tick-sched.c
scheduler changes in multiple branches
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (106 commits)
perf kvm: Fix copy & paste error in description
perf script: Kill script_spec__delete
perf top: Fix a memory leak
perf stat: Introduce get_ratio_color() helper
perf session: Remove impossible condition check
perf tools: Fix feature-bits rework fallout, remove unused variable
perf script: Add generic perl handler to process events
perf tools: Use for_each_set_bit() to iterate over feature flags
perf tools: Unify handling of features when writing feature section
perf report: Accept fifos as input file
perf tools: Moving code in some files
perf tools: Fix out-of-bound access to struct perf_session
perf tools: Continue processing header on unknown features
perf tools: Improve macros for struct feature_ops
perf: builtin-record: Document and check that mmap_pages must be a power of two.
perf: builtin-record: Provide advice if mmap'ing fails with EPERM.
perf tools: Fix truncated annotation
perf script: look up thread using tid instead of pid
perf tools: Look up thread names for system wide profiling
perf tools: Fix comm for processes with named threads
...
It appears about all functions in arch/x86/lib/atomic64_cx8_32.S
are wrong in case cmpxchg8b must be restarted, because
LOCK_PREFIX macro defines a label "1" clashing with other local
labels :
1:
some_instructions
LOCK_PREFIX
cmpxchg8b (%ebp)
jne 1b / jumps to beginning of LOCK_PREFIX !
A possible fix is to use a magic label "672" in LOCK_PREFIX asm
definition, similar to the "671" one we defined in
LOCK_PREFIX_HERE.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Jan Beulich <JBeulich@suse.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1325608540.2320.103.camel@edumazet-HP-Compaq-6005-Pro-SFF-PC
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Just like the per-CPU ones they had several
problems/shortcomings:
Only the first memory operand was mentioned in the asm()
operands, and the 2x64-bit version didn't have a memory clobber
while the 2x32-bit one did. The former allowed the compiler to
not recognize the need to re-load the data in case it had it
cached in some register, while the latter was overly
destructive.
The types of the local copies of the old and new values were
incorrect (the types of the pointed-to variables should be used
here, to make sure the respective old/new variable types are
compatible).
The __dummy/__junk variables were pointless, given that local
copies of the inputs already existed (and can hence be used for
discarded outputs).
The 32-bit variant of cmpxchg_double_local() referenced
cmpxchg16b_local().
At once also:
- change the return value type to what it really is: 'bool'
- unify 32- and 64-bit variants
- abstract out the common part of the 'normal' and 'local' variants
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/4F01F12A020000780006A19B@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a helper function that emulates the RDPMC instruction operation.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Use perf_events to emulate an architectural PMU, version 2.
Based on PMU version 1 emulation by Avi Kivity.
[avi: adjust for cpuid.c]
[jan: fix anonymous field initialization for older gcc]
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Move the mmu code in kvm_arch_vcpu_init() to kvm_mmu_create()
Signed-off-by: Xiao Guangrong <xiaoguangrong@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Intel latest cpu add 6 new features, refer http://software.intel.com/file/36945
The new feature cpuid listed as below:
1. FMA CPUID.EAX=01H:ECX.FMA[bit 12]
2. MOVBE CPUID.EAX=01H:ECX.MOVBE[bit 22]
3. BMI1 CPUID.EAX=07H,ECX=0H:EBX.BMI1[bit 3]
4. AVX2 CPUID.EAX=07H,ECX=0H:EBX.AVX2[bit 5]
5. BMI2 CPUID.EAX=07H,ECX=0H:EBX.BMI2[bit 8]
6. LZCNT CPUID.EAX=80000001H:ECX.LZCNT[bit 5]
This patch expose these features to guest.
Among them, FMA/MOVBE/LZCNT has already been defined, MOVBE/LZCNT has
already been exposed.
This patch defines BMI1/AVX2/BMI2, and exposes FMA/BMI1/AVX2/BMI2 to guest.
Signed-off-by: Liu, Jinsong <jinsong.liu@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently, write protecting a slot needs to walk all the shadow pages
and checks ones which have a pte mapping a page in it.
The walk is overly heavy when dirty pages in that slot are not so many
and checking the shadow pages would result in unwanted cache pollution.
To mitigate this problem, we use rmap_write_protect() and check only
the sptes which can be reached from gfns marked in the dirty bitmap
when the number of dirty pages are less than that of shadow pages.
This criterion is reasonable in its meaning and worked well in our test:
write protection became some times faster than before when the ratio of
dirty pages are low and was not worse even when the ratio was near the
criterion.
Note that the locking for this write protection becomes fine grained.
The reason why this is safe is descripted in the comments.
Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Avi Kivity <avi@redhat.com>
The host side pv mmu support has been marked for feature removal in
January 2011. It's not in use, is slower than shadow or hardware
assisted paging, and a maintenance burden. It's November 2011, time to
remove it.
Signed-off-by: Chris Wright <chrisw@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Detecting write-flooding does not work well, when we handle page written, if
the last speculative spte is not accessed, we treat the page is
write-flooding, however, we can speculative spte on many path, such as pte
prefetch, page synced, that means the last speculative spte may be not point
to the written page and the written page can be accessed via other sptes, so
depends on the Accessed bit of the last speculative spte is not enough
Instead of detected page accessed, we can detect whether the spte is accessed
after it is written, if the spte is not accessed but it is written frequently,
we treat is not a page table or it not used for a long time
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Fast prefetch spte for the unsync shadow page on invlpg path
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
In current code, the accessed bit is always set when page fault occurred,
do not need to set it on pte write path
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
If the emulation is caused by #PF and it is non-page_table writing instruction,
it means the VM-EXIT is caused by shadow page protected, we can zap the shadow
page and retry this instruction directly
The idea is from Avi
Signed-off-by: Xiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
Currently "nox2apic" boot parameter was not enabling x2apic mode if the cpu,
kernel are all capable of enabling x2apic mode and the OS handover
happened in xapic mode.
However If the bios enabled x2apic prior to OS handover, using "nox2apic"
boot parameter had no effect.
If the boot cpu's apicid is < 255, enable "nox2apic" boot parameter to
disable the x2apic mode setup by the bios. This will enable the kernel to
fallback to xapic mode and bringup only the cpu's which has apic-id < 255.
-v2: fix patch error and two compiling warning
make disable_x2apic to be __init
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/r/CAE9FiQUeB-3uxJAMiHsz=uPWoFv5Hg1pVepz7aU6YtqOxMC-=Q@mail.gmail.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
On some of the recent Intel SNB platforms, by default bios is pre-enabling
x2apic mode in the cpu with out setting up interrupt-remapping.
This case was resulting in the kernel to panic as the cpu is already in
x2apic mode but the OS was not able to enable interrupt-remapping (which
is a pre-req for using x2apic capability).
On these platforms all the apic-ids are < 255 and the kernel can fallback to
xapic mode if the bios has not enabled interrupt-remapping (which is
mostly the case if the bios has not exported interrupt-remapping tables to the
OS).
Reported-by: Berck E. Nash <flyboy@gmail.com>
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/20111222014632.600418637@sbsiddha-desk.sc.intel.com
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
We simply say that regular this_cpu use must be safe regardless of
preemption and interrupt state. That has no material change for x86
and s390 implementations of this_cpu operations. However, arches that
do not provide their own implementation for this_cpu operations will
now get code generated that disables interrupts instead of preemption.
-tj: This is part of on-going percpu API cleanup. For detailed
discussion of the subject, please refer to the following thread.
http://thread.gmane.org/gmane.linux.kernel/1222078
Signed-off-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
LKML-Reference: <alpine.DEB.2.00.1112221154380.11787@router.home>
This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.
After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.
Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Metcalf <cmetcalf@tilera.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Borislav Petkov <bp@amd64.org>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Len Brown <lenb@kernel.org>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Dave Jones <davej@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* master: (848 commits)
SELinux: Fix RCU deref check warning in sel_netport_insert()
binary_sysctl(): fix memory leak
mm/vmalloc.c: remove static declaration of va from __get_vm_area_node
ipmi_watchdog: restore settings when BMC reset
oom: fix integer overflow of points in oom_badness
memcg: keep root group unchanged if creation fails
nilfs2: potential integer overflow in nilfs_ioctl_clean_segments()
nilfs2: unbreak compat ioctl
cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask
evm: prevent racing during tfm allocation
evm: key must be set once during initialization
mmc: vub300: fix type of firmware_rom_wait_states module parameter
Revert "mmc: enable runtime PM by default"
mmc: sdhci: remove "state" argument from sdhci_suspend_host
x86, dumpstack: Fix code bytes breakage due to missing KERN_CONT
IB/qib: Correct sense on freectxts increment and decrement
RDMA/cma: Verify private data length
cgroups: fix a css_set not found bug in cgroup_attach_proc
oprofile: Fix uninitialized memory access when writing to writing to oprofilefs
Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel"
...
Conflicts:
kernel/cgroup_freezer.c
Mathieu Desnoyers pointed out a case that can cause issues with
NMIs running on the debug stack:
int3 -> interrupt -> NMI -> int3
Because the interrupt changes the stack, the NMI will not see that
it preempted the debug stack. Looking deeper at this case,
interrupts only happen when the int3 is from userspace or in
an a location in the exception table (fixup).
userspace -> int3 -> interurpt -> NMI -> int3
All other int3s that happen in the kernel should be processed
without ever enabling interrupts, as the do_trap() call will
panic the kernel if it is called to process any other location
within the kernel.
Adding a counter around the sections that enable interrupts while
using the debug stack allows the NMI to also check that case.
If the NMI sees that it either interrupted a task using the debug
stack or the debug counter is non-zero, then it will have to
change the IDT table to make the int3 not change stacks (which will
corrupt the stack if it does).
Note, I had to move the debug_usage functions out of processor.h
and into debugreg.h because of the static inlined functions to
inc and dec the debug_usage counter. __get_cpu_var() requires
smp.h which includes processor.h, and would fail to build.
Link: http://lkml.kernel.org/r/1323976535.23971.112.camel@gandalf.stny.rr.com
Reported-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul Turner <pjt@google.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
We want to allow NMI handlers to have breakpoints to be able to
remove stop_machine from ftrace, kprobes and jump_labels. But if
an NMI interrupts a current breakpoint, and then it triggers a
breakpoint itself, it will switch to the breakpoint stack and
corrupt the data on it for the breakpoint processing that it
interrupted.
Instead, have the NMI check if it interrupted breakpoint processing
by checking if the stack that is currently used is a breakpoint
stack. If it is, then load a special IDT that changes the IST
for the debug exception to keep the same stack in kernel context.
When the NMI is done, it puts it back.
This way, if the NMI does trigger a breakpoint, it will keep
using the same stack and not stomp on the breakpoint data for
the breakpoint it interrupted.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This patch adds the encoding and definitions necessary for the
unhalted_reference_cycles event avaialble since Intel Core 2 processors.
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1323559734-3488-2-git-send-email-eranian@google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Several fields in struct cpuinfo_x86 were not defined for the
!SMP case, likely to save space. However, those fields still
have some meaning for UP, and keeping them allows some #ifdef
removal from other files. The additional size of the UP kernel
from this change is not significant enough to worry about
keeping up the distinction:
text data bss dec hex filename
4737168 506459 972040 6215667 5ed7f3 vmlinux.o.before
4737444 506459 972040 6215943 5ed907 vmlinux.o.after
for a difference of 276 bytes for an example UP config.
If someone wants those 276 bytes back badly then it should
be implemented in a cleaner way.
Signed-off-by: Kevin Winchester <kjwinchester@gmail.com>
Cc: Steffen Persvold <sp@numascale.com>
Link: http://lkml.kernel.org/r/1324428742-12498-1-git-send-email-kjwinchester@gmail.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
LAPIC related statistics are grouped inside the per-cpu
structure irq_stat, so there is no need for icr_read_retry_count
to be a standalone per-cpu variable.
This patch moves icr_read_retry_count to where it belongs.
Suggested-y: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: Jörn Engel <joern@logfs.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
gcc noticed (when using -Wempty-body) that our use of
lock_cmos() and unlock_cmos() in
arch/x86/include/asm/mach_traps.h is potentially problematic :
arch/x86/include/asm/mach_traps.h:32:15: warning: suggest braces around empty body in an ¡else¢ statement [-Wempty-body]
arch/x86/include/asm/mach_traps.h:40:16: warning: suggest braces around empty body in an ¡else¢ statement [-Wempty-body]
Let's just use the standard 'do {} while (0)' solution. That
shuts up gcc and also prevents future problems if the macros
should end up being used in a similar situation elsewhere.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1112180103130.21784@swampdragon.chaosbits.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
If one builds the kernel with -Wempty-body one gets this
warning:
mm/memory.c:3432:46: warning: suggest braces around empty body in an ¡if¢ statement [-Wempty-body]
due to the fact that 'flush_tlb_fix_spurious_fault' is a macro
that can sometimes be defined to nothing.
Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-mm@kvack.org
Cc: Michel Lespinasse <walken@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Link: http://lkml.kernel.org/r/alpine.LNX.2.00.1112180128070.21784@swampdragon.chaosbits.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
mce-inject provides a mechanism to simulate errors so that test
scripts can check for correct operation of the kernel without
requiring any specialized hardware to create rare events.
The existing code can simulate events in normal process context
and also in NMI context - but not in IRQ context. This patch
fills that gap.
Link: https://lkml.org/lkml/2011/12/7/537
Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
fls(N), ffs(N) and fls64(N) can be optimised on x86_64. Currently they use a
CMOV instruction after the BSR/BSF to set the destination register to -1 if the
value to be scanned was 0 (in which case BSR/BSF set the Z flag).
Instead, according to the AMD64 specification, we can make use of the fact that
BSR/BSF doesn't modify its output register if its input is 0. By preloading
the output with -1 and incrementing the result, we achieve the desired result
without the need for a conditional check.
The Intel x86_64 specification, however, says that the result of BSR/BSF in
such a case is undefined. That said, when queried, one of the Intel CPU
architects said that the behaviour on all Intel CPUs is that:
(1) with BSRQ/BSFQ, the 64-bit destination register is written with its
original value if the source is 0, thus, in essence, giving the effect we
want. And,
(2) with BSRL/BSFL, the lower half of the 64-bit destination register is
written with its original value if the source is 0, and the upper half is
cleared, thus giving us the effect we want (we return a 4-byte int).
Further, it was indicated that they (Intel) are unlikely to get away with
changing the behaviour.
It might be possible to optimise the 32-bit versions of these functions, but
there's a lot more variation, and so the effective non-destructive property of
BSRL/BSRF cannot be relied on.
[ hpa: specifically, some 486 chips are known to NOT have this property. ]
I have benchmarked these functions on my Core2 Duo test machine using the
following program:
#include <stdlib.h>
#include <stdio.h>
#ifndef __x86_64__
#error
#endif
#define PAGE_SHIFT 12
typedef unsigned long long __u64, u64;
typedef unsigned int __u32, u32;
#define noinline __attribute__((noinline))
static __always_inline int fls64(__u64 x)
{
long bitpos = -1;
asm("bsrq %1,%0"
: "+r" (bitpos)
: "rm" (x));
return bitpos + 1;
}
static inline unsigned long __fls(unsigned long word)
{
asm("bsr %1,%0"
: "=r" (word)
: "rm" (word));
return word;
}
static __always_inline int old_fls64(__u64 x)
{
if (x == 0)
return 0;
return __fls(x) + 1;
}
static noinline // __attribute__((const))
int old_get_order(unsigned long size)
{
int order;
size = (size - 1) >> (PAGE_SHIFT - 1);
order = -1;
do {
size >>= 1;
order++;
} while (size);
return order;
}
static inline __attribute__((const))
int get_order_old_fls64(unsigned long size)
{
int order;
size--;
size >>= PAGE_SHIFT;
order = old_fls64(size);
return order;
}
static inline __attribute__((const))
int get_order(unsigned long size)
{
int order;
size--;
size >>= PAGE_SHIFT;
order = fls64(size);
return order;
}
unsigned long prevent_optimise_out;
static noinline unsigned long test_old_get_order(void)
{
unsigned long n, total = 0;
long rep, loop;
for (rep = 1000000; rep > 0; rep--) {
for (loop = 0; loop <= 16384; loop += 4) {
n = 1UL << loop;
total += old_get_order(n);
}
}
return total;
}
static noinline unsigned long test_get_order_old_fls64(void)
{
unsigned long n, total = 0;
long rep, loop;
for (rep = 1000000; rep > 0; rep--) {
for (loop = 0; loop <= 16384; loop += 4) {
n = 1UL << loop;
total += get_order_old_fls64(n);
}
}
return total;
}
static noinline unsigned long test_get_order(void)
{
unsigned long n, total = 0;
long rep, loop;
for (rep = 1000000; rep > 0; rep--) {
for (loop = 0; loop <= 16384; loop += 4) {
n = 1UL << loop;
total += get_order(n);
}
}
return total;
}
int main(int argc, char **argv)
{
unsigned long total;
switch (argc) {
case 1: total = test_old_get_order(); break;
case 2: total = test_get_order_old_fls64(); break;
default: total = test_get_order(); break;
}
prevent_optimise_out = total;
return 0;
}
This allows me to test the use of the old fls64() implementation and the new
fls64() implementation and also to contrast these to the out-of-line loop-based
implementation of get_order(). The results were:
warthog>time ./get_order
real 1m37.191s
user 1m36.313s
sys 0m0.861s
warthog>time ./get_order x
real 0m16.892s
user 0m16.586s
sys 0m0.287s
warthog>time ./get_order x x
real 0m7.731s
user 0m7.727s
sys 0m0.002s
Using the current upstream fls64() as a basis for an inlined get_order() [the
second result above] is much faster than using the current out-of-line
loop-based get_order() [the first result above].
Using my optimised inline fls64()-based get_order() [the third result above]
is even faster still.
[ hpa: changed the selection of 32 vs 64 bits to use CONFIG_X86_64
instead of comparing BITS_PER_LONG, updated comments, rebased manually
on top of 83d99df7c4 x86, bitops: Move fls64.h inside __KERNEL__ ]
Signed-off-by: David Howells <dhowells@redhat.com>
Link: http://lkml.kernel.org/r/20111213145654.14362.39868.stgit@warthog.procyon.org.uk
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
We would include <asm-generic/bitops/fls64.h> even without __KERNEL__,
but that doesn't make sense, as:
1. That file provides fls64(), but the corresponding function fls() is
not exported to user space.
2. The implementation of fls64.h uses kernel-only symbols.
3. fls64.h is not exported to user space.
This appears to have been a bug introduced in checkin:
d57594c203 bitops: use __fls for fls64 on 64-bit archs
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Alexander van Heukelum <heukelum@mailshack.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Link: http://lkml.kernel.org/r/4EEA77E1.6050009@zytor.com
They had several problems/shortcomings:
Only the first memory operand was mentioned in the 2x32bit asm()
operands, and 2x64-bit version had a memory clobber. The first
allowed the compiler to not recognize the need to re-load the
data in case it had it cached in some register, and the second
was overly destructive.
The memory operand in the 2x32-bit asm() was declared to only be
an output.
The types of the local copies of the old and new values were
incorrect (as in other per-CPU ops, the types of the per-CPU
variables accessed should be used here, to make sure the
respective types are compatible).
The __dummy variable was pointless (and needlessly initialized
in the 2x32-bit case), given that local copies of the inputs
already exist.
The 2x64-bit variant forced the address of the first object into
%rsi, even though this is needed only for the call to the
emulation function. The real cmpxchg16b can operate on an
memory.
At once also change the return value type to what it really is -
'bool'.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/4EE86D6502000078000679FE@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
No functionality change, this is done so that in a follow-on patch all
queued-up MCEs can be decoded after registering on the chain.
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
In the IPI delivery slow path (NMI delivery) we retry the ICR
read to check for delivery completion a limited number of times.
[ The reason for the limited retries is that some of the places
where it is used (cpu boot, kdump, etc) IPI delivery might not
succeed (due to a firmware bug or system crash, for example)
and in such a case it is better to give up and resume
execution of other code. ]
This patch adds a new entry to /proc/interrupts, RTR, which
tells user space the number of times we retried the ICR read in
the IPI delivery slow path.
This should give some insight into how well the APIC
message delivery hardware is working - if the counts are way
too large then we are hitting a (very-) slow path way too
often.
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Cc: Jörn Engel <joern@logfs.org>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Link: http://lkml.kernel.org/n/tip-vzsp20lo2xdzh5f70g0eis2s@git.kernel.org
[ extended the changelog ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This hangs my MacBook Air at boot time; I get no console
messages at all. I reverted this on top of -rc5 and my machine
boots again.
This reverts commit e8c7106280.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Introduce a symbol, EFI_LOADER_SIGNATURE instead of using the magic
strings, which also helps to reduce the amount of ifdeffery.
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
commit 37ba7ab5e3 ("x86, boot: make kernel_alignment adjustable; new
bzImage fields") introduced some new fields into the bzImage header
but struct setup_header was not updated accordingly. Add the missing
'pref_address' and 'init_size' fields.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Link: http://lkml.kernel.org/r/1318848017-12301-1-git-send-email-matt@console-pimps.org
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
If we encounter an efi_memory_desc_t without EFI_MEMORY_WB set
in ->attribute we currently call set_memory_uc(), which in turn
calls __pa() on a potentially ioremap'd address.
On CONFIG_X86_32 this is invalid, resulting in the following
oops on some machines:
BUG: unable to handle kernel paging request at f7f22280
IP: [<c10257b9>] reserve_ram_pages_type+0x89/0x210
[...]
Call Trace:
[<c104f8ca>] ? page_is_ram+0x1a/0x40
[<c1025aff>] reserve_memtype+0xdf/0x2f0
[<c1024dc9>] set_memory_uc+0x49/0xa0
[<c19334d0>] efi_enter_virtual_mode+0x1c2/0x3aa
[<c19216d4>] start_kernel+0x291/0x2f2
[<c19211c7>] ? loglevel+0x1b/0x1b
[<c19210bf>] i386_start_kernel+0xbf/0xc8
A better approach to this problem is to map the memory region
with the correct attributes from the start, instead of modifying
it after the fact. The uncached case can be handled by
ioremap_nocache() and the cached by ioremap_cache().
Despite first impressions, it's not possible to use
ioremap_cache() to map all cached memory regions on
CONFIG_X86_64 because EFI_RUNTIME_SERVICES_DATA regions really
don't like being mapped into the vmalloc space, as detailed in
the following bug report,
https://bugzilla.redhat.com/show_bug.cgi?id=748516
Therefore, we need to ensure that any EFI_RUNTIME_SERVICES_DATA
regions are covered by the direct kernel mapping table on
CONFIG_X86_64. To accomplish this we now map E820_RESERVED_EFI
regions via the direct kernel mapping with the initial call to
init_memory_mapping() in setup_arch(), whereas previously these
regions wouldn't be mapped if they were after the last E820_RAM
region until efi_ioremap() was called. Doing it this way allows
us to delete efi_ioremap() completely.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Matthew Garrett <mjg@redhat.com>
Cc: Zhang Rui <rui.zhang@intel.com>
Cc: Huang Ying <huang.ying.caritas@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1321621751-3650-1-git-send-email-matt@console-pimps.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The node_distance function is not x86 64-bit specific. Having
the #ifdef around the extern function declaration and the
#define causes the default node_distance macro to be used in
asm-generic/topology.h. This also causes a sparse warning in
arch/x86/mm/numa.c when CONFIG_X86_64 is not set:
warning: symbol '__node_distance' was not declared. Should it be
static?
Remove the #ifdef to fix both issues.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1112061220310.28251@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
KVM needs to know perf capability to decide which PMU it can expose to a
guest.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1320929850-10480-8-git-send-email-gleb@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Intel CPUs report non-available architectural events in cpuid leaf
0AH.EBX. Use it to disable events that are not available according
to CPU.
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1320929850-10480-7-git-send-email-gleb@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The x86_64 kernel pushes the fake kernel stack in
arch/x86/kernel/entry_64.S:FAKE_STACK_FRAME, and
rflags register in it does not conform to the specification.
Although Intel's manual[1] says bit 1 of it shall be set to 1,
this bit is cleared to 0 on pushing the fake stack.
[1] Intel(R) 64 and IA-32 Architectures Software Developer's Manual
Vol.1 3-21 Figure 3-8. EFLAGS Register
If it is not on purpose, it is better to be fixed, because
it can lead some tools misunderstanding the stack frame. For example,
"crash" utility[2] actually detects it and warns you like
below:
RIP: ffffffff8005dfa2 RSP: ffff8104ce0c7f58 RFLAGS: 00000200
[...]
bt: WARNING: possibly bogus exception frame
Signed-off-by: Seiichi Ikarashi <s.ikarashi@jp.fujitsu.com>
Tested-by: Masayoshi MIZUMA <m.mizuma@jp.fujitsu.com>
Cc: Jan Beulich <JBeulich@suse.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch changes fields in cpustat from a structure, to an
u64 array. Math gets easier, and the code is more flexible.
Signed-off-by: Glauber Costa <glommer@parallels.com>
Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Tuner <pjt@google.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1322498719-2255-2-git-send-email-glommer@parallels.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
intr_remapping: Fix section mismatch in ir_dev_scope_init()
intel-iommu: Fix section mismatch in dmar_parse_rmrr_atsr_dev()
x86, amd: Fix up numa_node information for AMD CPU family 15h model 0-0fh northbridge functions
x86, AMD: Correct align_va_addr documentation
x86/rtc, mrst: Don't register a platform RTC device for for Intel MID platforms
x86/mrst: Battery fixes
x86/paravirt: PTE updates in k(un)map_atomic need to be synchronous, regardless of lazy_mmu mode
x86: Fix "Acer Aspire 1" reboot hang
x86/mtrr: Resolve inconsistency with Intel processor manual
x86: Document rdmsr_safe restrictions
x86, microcode: Fix the failure path of microcode update driver init code
Add TAINT_FIRMWARE_WORKAROUND on MTRR fixup
x86/mpparse: Account for bus types other than ISA and PCI
x86, mrst: Change the pmic_gpio device type to IPC
mrst: Added some platform data for the SFI translations
x86,mrst: Power control commands update
x86/reboot: Blacklist Dell OptiPlex 990 known to require PCI reboot
x86, UV: Fix UV2 hub part number
x86: Add user_mode_vm check in stack_overflow_check
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched, x86: Avoid unnecessary overflow in sched_clock
sched: Fix buglet in return_cfs_rq_runtime()
sched: Avoid SMT siblings in select_idle_sibling() if possible
sched: Set the command name of the idle tasks in SMP kernels
sched, rt: Provide means of disabling cross-cpu bandwidth sharing
sched: Document wait_for_completion_*() return values
sched_fair: Fix a typo in the comment describing update_sd_lb_stats
sched: Add a comment to effective_load() since it's a pain
In the target code I have a do_div(x, PAGE_SIZE). The x86-64
version of it was doing a shift and a mask which is clever. The
32bit version of it had a div operation in it which made me
think. After digging I noticed that x86 has an optimized version
of it. This patch adds this shift and mask optimization if base
is constant so we don't have any runtime "checking" overhead
since most users use a power of ten.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1322649814-544-1-git-send-email-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@elte.hu>
tsc=reliable boot parameter is supposed to skip all the TSC
stablility checks during boot time.
On a 8-socket system where we want to run an experiment with the
"tsc=reliable" boot option, TSC synchronization checks are not
getting skipped and marking the TSC as not stable.
Check for tsc_clocksource_reliable (which is set via
tsc=reliable or for platforms supporting synthetic TSC_RELIABLE
feature bit etc) and when set, skip the TSC synchronization
tests during boot.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1320446537.15071.14.camel@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
GET_THREAD_INFO() involves a memory read immediately followed by
an "sub" on the value read, in turn (in several cases)
immediately followed by a use of the calculated value as the
base address of a memory access. This combination of
instructions has a non-negligible potential for stalls.
In the system call entry point code, however, the (fixed) offset
of the stack pointer from the end of the stack is generally
known, and hence we can instead avoid the memory load and
subtract, and instead do the memory reference using %rsp as the
base register. To do so in a legible fashion, introduce a
THREAD_INFO() macro which, provided a register (generally %rsp)
and the known offset from the end of the stack, produces a
suitable memory access operand.
The patch attempts to only touch the fast paths (no auditing and
alike), but manages to do so only in the 64-bit entry point
case; the compatibility mode entry points have so many
interdependencies between their various branch targets that it
was necessary to also adjust the slow paths to eliminate the
risk of having missed some register dependency during code
analysis.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Link: http://lkml.kernel.org/r/4ED4CD690200007800064075@nat28.tlf.novell.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Adds support for Numascale NumaChip large-SMP systems. It is
needed to enable the booting of more than ~168 cores.
v2:
- [Steffen] enumerate only accessible northbridges
- [Daniel] rediffed and validated against 3.1-rc10
v3:
- [Daniel] use x86_init core numbering override
- [Daniel] cleanups as per feedback
v4:
- [Daniel] use updated x86_cpuinit override
v5:
- drop disabling interrupts locally, as ISR write is atomic; drop delay
- added read-mostly annotations where appropriate
- require CONFIG_SMP, so drop conditional path
Workload tested on 96 cores/16 sockets.
Signed-off-by: Steffen Persvold <sp@numascale.com>
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Link: http://lkml.kernel.org/r/1323101246-2400-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add an x86_init vector for handling inconsistent core numbering.
This is useful for multi-fabric platforms, such as Numascale
NumaConnect.
v2:
- use struct x86_cpuinit_ops
- provide default fall-back function to warn
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Link: http://lkml.kernel.org/r/1323073238-32686-2-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Allow flat_init_apic_ldr() to be used outside the compilation
unit for similar APIC implementations.
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: Steffen Persvold <sp@numascale.com>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Link: http://lkml.kernel.org/r/1323073238-32686-1-git-send-email-daniel@numascale-asia.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Intel MID x86 platforms have a memory mapped virtual RTC
instead. No MID platform have the default ports (and
accessing them may do weird stuff).
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: feng.tang@intel.com
Cc: Feng Tang <feng.tang@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Recently, I got bitten by using rdmsr_safe too early in the boot
process. Document its shortcomings for future reference.
Link: http://lkml.kernel.org/r/4ED5B70F.606@lwfinger.net
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
On the Intel MID devices SCU commands are issued to manage power
off and the like. We need to issue different ones for
non-Lincroft based devices.
Signed-off-by: Alek Du <alek.du@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
To make this work, we teach the page fault handler how to send
signals on failed uaccess. This only works for user addresses
(kernel addresses will never hit the page fault handler in the
first place), so we need to generate signals for those
separately.
This gets the tricky case right: if the user buffer spans
multiple pages and only the second page is invalid, we set
cr2 and si_addr correctly. UML relies on this behavior to
"fault in" pages as needed.
We steal a bit from thread_info.uaccess_err to enable this.
Before this change, uaccess_err was a 32-bit boolean value.
This fixes issues with UML when vsyscall=emulate.
Reported-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: H. Peter Anvin <hpa@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/4c8f91de7ec5cd2ef0f59521a04e1015f11e42b4.1320712291.git.luto@amacapital.net
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The previous patch modified the stop cpus path to use NMI
instead of IRQ as the way to communicate to the other cpus to
shutdown. There were some concerns that various machines may
have problems with using an NMI IPI.
This patch creates a selftest to check if NMI is working at
boot. The idea is to help catch any issues before the machine
panics and we learn the hard way.
Loosely based on the locking-selftest.c file, this separate file
runs a couple of simple tests and reports the results. The
output looks like:
...
Brought up 4 CPUs
----------------
| NMI testsuite:
--------------------
remote IPI: ok |
local IPI: ok |
--------------------
Good, all 2 testcases passed! |
---------------------------------
Total of 4 processors activated (21330.61 BogoMIPS).
...
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Richter <robert.richter@amd.com>
Cc: seiji.aguchi@hds.com
Cc: vgoyal@redhat.com
Cc: mjg@redhat.com
Cc: tony.luck@intel.com
Cc: gong.chen@intel.com
Cc: satoru.moriya@hds.com
Cc: avi@redhat.com
Cc: Andi Kleen <andi@firstfloor.org>
Link: http://lkml.kernel.org/r/1318533267-18880-3-git-send-email-dzickus@redhat.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
There was a mixup when the SGI UV2 hub chip was sent to be
fabricated, and it ended up with the wrong part number in the
HRP_NODE_ID mmr. Future versions of the chip will (may) have the
correct part number. Change the UV infrastructure to recognize
both part numbers as valid IDs of a UV2 hub chip.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Link: http://lkml.kernel.org/r/20111129210058.GA20452@sgi.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The idea behind commit d91ee5863b ("cpuidle: replace xen access to x86
pm_idle and default_idle") was to have one call - disable_cpuidle()
which would make pm_idle not be molested by other code. It disallows
cpuidle_idle_call to be set to pm_idle (which is excellent).
But in the select_idle_routine() and idle_setup(), the pm_idle can still
be set to either: amd_e400_idle, mwait_idle or default_idle. This
depends on some CPU flags (MWAIT) and in AMD case on the type of CPU.
In case of mwait_idle we can hit some instances where the hypervisor
(Amazon EC2 specifically) sets the MWAIT and we get:
Brought up 2 CPUs
invalid opcode: 0000 [#1] SMP
Pid: 0, comm: swapper Not tainted 3.1.0-0.rc6.git0.3.fc16.x86_64 #1
RIP: e030:[<ffffffff81015d1d>] [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
...
Call Trace:
[<ffffffff8100e2ed>] cpu_idle+0xae/0xe8
[<ffffffff8149ee78>] cpu_bringup_and_idle+0xe/0x10
RIP [<ffffffff81015d1d>] mwait_idle+0x6f/0xb4
RSP <ffff8801d28ddf10>
In the case of amd_e400_idle we don't get so spectacular crashes, but we
do end up making an MSR which is trapped in the hypervisor, and then
follow it up with a yield hypercall. Meaning we end up going to
hypervisor twice instead of just once.
The previous behavior before v3.0 was that pm_idle was set to
default_idle regardless of select_idle_routine/idle_setup.
We want to do that, but only for one specific case: Xen. This patch
does that.
Fixes RH BZ #739499 and Ubuntu #881076
Reported-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Conflicts & resolutions:
* arch/x86/xen/setup.c
dc91c728fd "xen: allow extra memory to be in multiple regions"
24aa07882b "memblock, x86: Replace memblock_x86_reserve/free..."
conflicted on xen_add_extra_mem() updates. The resolution is
trivial as the latter just want to replace
memblock_x86_reserve_range() with memblock_reserve().
* drivers/pci/intel-iommu.c
166e9278a3 "x86/ia64: intel-iommu: move to drivers/iommu/"
5dfe8660a3 "bootmem: Replace work_with_active_regions() with..."
conflicted as the former moved the file under drivers/iommu/.
Resolved by applying the chnages from the latter on the moved
file.
* mm/Kconfig
6661672053 "memblock: add NO_BOOTMEM config symbol"
c378ddd53f "memblock, x86: Make ARCH_DISCARD_MEMBLOCK a config option"
conflicted trivially. Both added config options. Just
letting both add their own options resolves the conflict.
* mm/memblock.c
d1f0ece6cd "mm/memblock.c: small function definition fixes"
ed7b56a799 "memblock: Remove memblock_memory_can_coalesce()"
confliected. The former updates function removed by the
latter. Resolution is trivial.
Signed-off-by: Tejun Heo <tj@kernel.org>
They both have a basic "put new value in location, return old value"
pattern, so they can use the same macro easily.
Signed-off-by: Jeremy Fitzhardinge <jeremy@goop.org>
CLOCK_TICK_RATE is defined as PIT_TICK_RATE on x86 so we
update mach_timers.h to just use the later as we want
to depecrate CLOCK_TICK_RATE.
Signed-off-by: Deepak Saxena <dsaxena@linaro.org>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Generate system call tables and unistd_*.h automatically from the
tables in arch/x86/syscalls. All other information, like NR_syscalls,
is auto-generated, some of which is in asm-offsets_*.c.
This allows us to keep all the system call information in one place,
and allows for kernel space and user space to see different
information; this is currently used for the ia32 system call numbers
when building the 64-bit kernel, but will be used by the x32 ABI in
the near future.
This also removes some gratuitious differences between i386, x86-64
and ia32; in particular, now all system call tables are generated with
the same mechanism.
Cc: H. J. Lu <hjl.tools@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
(Added the missing signed-off-by line)
In hundreds of days, the __cycles_2_ns calculation in sched_clock
has an overflow. cyc * per_cpu(cyc2ns, cpu) exceeds 64 bits, causing
the final value to become zero. We can solve this without losing
any precision.
We can decompose TSC into quotient and remainder of division by the
scale factor, and then use this to convert TSC into nanoseconds.
Signed-off-by: Salman Qazi <sqazi@google.com>
Acked-by: John Stultz <johnstul@us.ibm.com>
Reviewed-by: Paul Turner <pjt@google.com>
Cc: stable@kernel.org
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20111115221121.7262.88871.stgit@dungbeetle.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add support to specify which HSU port to use as an early console. This can
be selected by passing "earlyprintk=hsu<n>" on the kernel command line. By
default port 0 is still used.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The option iommu=group_mf indicates the that the iommu driver should
expose all functions of a multi-function PCI device as the same
iommu_device_group. This is useful for disallowing individual functions
being exposed as independent devices to userspace as there are often
hidden dependencies. Virtual functions are not affected by this option.
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Now that zone_sizes_init() is identical on 32-bit and 64-bit,
move the code to arch/x86/mm/init.c and use it for both
architectures.
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Pekka Enberg <penberg@kernel.org>
Link: http://lkml.kernel.org/r/1320155902-10424-7-git-send-email-penberg@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Moorestown/Medfield platform does not have port 0x61 to report
NMI status, nor does it have external NMI sources. The only NMI
sources are from lapic, as results of perf counter overflow or
IPI, e.g. NMI watchdog or spin lock debug.
Reading port 0x61 on Moorestown will return 0xff which misled
NMI handlers to false critical errors such memory parity error.
The subsequent ioport access for NMI handling can also cause
undefined behavior on Moorestown.
This patch allows kernel process NMI due to watchdog or backrace
dump without unnecessary hangs.
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[hand applied]
Signed-off-by: Alan Cox <alan@linux.intel.com>
lapic timer calibration can be combined with tsc in platform
specific calibration functions. if such calibration result is
obtained early, we can skip the redundant calibration loops.
Signed-off-by: Jacob Pan <jacob.jun.pan@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Some wall clock devices use MMIO based HW register, this new
function will give them a chance to do some initialization work
before their get/set_time service get called.
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Dirk Brandewie <dirk.brandewie@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add a sanity test of x86 insn decoder against a stream
of randomly generated input, at build time.
This test is also able to reproduce any bug that might
trigger by allowing the passing of random-seed and
iteration-number to the test, or by passing input
which has invalid byte code.
Changes in V2:
- Code cleanup.
- Show how to reproduce the error by insn_sanity test.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: acme@redhat.com
Cc: ming.m.lin@intel.com
Cc: robert.richter@amd.com
Cc: ravitillo@lbl.gov
Cc: yrl.pp-manager.tt@hitachi.com
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20111020140109.20938.92572.stgit@localhost.localdomain
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Arjan would like to make struct file_operations const, but
mce-inject directly writes to the mce_chrdev_ops to install its
write handler. In an ideal world mce-inject would have its own
character device, but we have a sizable legacy of test scripts
that hardwire "/dev/mcelog", so it would be painful to switch to
a separate device now. Instead, this patch switches to a stub
function in the mce code, with a registration helper that
mce-inject can call when it is loaded.
Note that this would also allow for a sane process to allow
mce-inject to be unloaded again (with an unregister function,
and appropriate module_{get,put}() calls), but that is left for
potential future patches.
Reported-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/4eb2e1971326651a3b@agluck-desktop.sc.intel.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'upstream/xen-settime' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen:
xen/dom0: set wallclock time in Xen
xen: add dom0_op hypercall
xen/acpi: Domain0 acpi parser related platform hypercall
* 'stable/vmalloc-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
net: xen-netback: use API provided by xenbus module to map rings
block: xen-blkback: use API provided by xenbus module to map rings
xen: use generic functions instead of xen_{alloc, free}_vm_area()
* 'for-next' of git://git.infradead.org/users/sameo/mfd-2.6: (80 commits)
mfd: Fix missing abx500 header file updates
mfd: Add missing <linux/io.h> include to intel_msic
x86, mrst: add platform support for MSIC MFD driver
mfd: Expose TurnOnStatus in ab8500 sysfs
mfd: Remove support for early drop ab8500 chip
mfd: Add support for ab8500 v3.3
mfd: Add ab8500 interrupt disable hook
mfd: Convert db8500-prcmu panic() into pr_crit()
mfd: Refactor db8500-prcmu request_clock() function
mfd: Rename db8500-prcmu init function
mfd: Fix db5500-prcmu defines
mfd: db8500-prcmu voltage domain consumers additions
mfd: db8500-prcmu reset code retrieval
mfd: db8500-prcmu tweak for modem wakeup
mfd: Add db8500-pcmu watchdog accessor functions for watchdog
mfd: hwacc power state db8500-prcmu accessor
mfd: Add db8500-prcmu accessors for PLL and SGA clock
mfd: Move to the new db500 PRCMU API
mfd: Create a common interface for dbx500 PRCMU drivers
mfd: Initialize DB8500 PRCMU regs
...
Fix up trivial conflicts in
arch/arm/mach-imx/mach-mx31moboard.c
arch/arm/mach-omap2/board-omap3beagle.c
arch/arm/mach-u300/include/mach/irqs.h
drivers/mfd/wm831x-spi.c
* git://github.com/herbertx/crypto: (48 commits)
crypto: user - Depend on NET instead of selecting it
crypto: user - Add dependency on NET
crypto: talitos - handle descriptor not found in error path
crypto: user - Initialise match in crypto_alg_match
crypto: testmgr - add twofish tests
crypto: testmgr - add blowfish test-vectors
crypto: Make hifn_795x build depend on !ARCH_DMA_ADDR_T_64BIT
crypto: twofish-x86_64-3way - fix ctr blocksize to 1
crypto: blowfish-x86_64 - fix ctr blocksize to 1
crypto: whirlpool - count rounds from 0
crypto: Add userspace report for compress type algorithms
crypto: Add userspace report for cipher type algorithms
crypto: Add userspace report for rng type algorithms
crypto: Add userspace report for pcompress type algorithms
crypto: Add userspace report for nivaead type algorithms
crypto: Add userspace report for aead type algorithms
crypto: Add userspace report for givcipher type algorithms
crypto: Add userspace report for ablkcipher type algorithms
crypto: Add userspace report for blkcipher type algorithms
crypto: Add userspace report for ahash type algorithms
...
The basic idea behind cross memory attach is to allow MPI programs doing
intra-node communication to do a single copy of the message rather than a
double copy of the message via shared memory.
The following patch attempts to achieve this by allowing a destination
process, given an address and size from a source process, to copy memory
directly from the source process into its own address space via a system
call. There is also a symmetrical ability to copy from the current
process's address space into a destination process's address space.
- Use of /proc/pid/mem has been considered, but there are issues with
using it:
- Does not allow for specifying iovecs for both src and dest, assuming
preadv or pwritev was implemented either the area read from or
written to would need to be contiguous.
- Currently mem_read allows only processes who are currently
ptrace'ing the target and are still able to ptrace the target to read
from the target. This check could possibly be moved to the open call,
but its not clear exactly what race this restriction is stopping
(reason appears to have been lost)
- Having to send the fd of /proc/self/mem via SCM_RIGHTS on unix
domain socket is a bit ugly from a userspace point of view,
especially when you may have hundreds if not (eventually) thousands
of processes that all need to do this with each other
- Doesn't allow for some future use of the interface we would like to
consider adding in the future (see below)
- Interestingly reading from /proc/pid/mem currently actually
involves two copies! (But this could be fixed pretty easily)
As mentioned previously use of vmsplice instead was considered, but has
problems. Since you need the reader and writer working co-operatively if
the pipe is not drained then you block. Which requires some wrapping to
do non blocking on the send side or polling on the receive. In all to all
communication it requires ordering otherwise you can deadlock. And in the
example of many MPI tasks writing to one MPI task vmsplice serialises the
copying.
There are some cases of MPI collectives where even a single copy interface
does not get us the performance gain we could. For example in an
MPI_Reduce rather than copy the data from the source we would like to
instead use it directly in a mathops (say the reduce is doing a sum) as
this would save us doing a copy. We don't need to keep a copy of the data
from the source. I haven't implemented this, but I think this interface
could in the future do all this through the use of the flags - eg could
specify the math operation and type and the kernel rather than just
copying the data would apply the specified operation between the source
and destination and store it in the destination.
Although we don't have a "second user" of the interface (though I've had
some nibbles from people who may be interested in using it for intra
process messaging which is not MPI). This interface is something which
hardware vendors are already doing for their custom drivers to implement
fast local communication. And so in addition to this being useful for
OpenMPI it would mean the driver maintainers don't have to fix things up
when the mm changes.
There was some discussion about how much faster a true zero copy would
go. Here's a link back to the email with some testing I did on that:
http://marc.info/?l=linux-mm&m=130105930902915&w=2
There is a basic man page for the proposed interface here:
http://ozlabs.org/~cyeoh/cma/process_vm_readv.txt
This has been implemented for x86 and powerpc, other architecture should
mainly (I think) just need to add syscall numbers for the process_vm_readv
and process_vm_writev. There are 32 bit compatibility versions for
64-bit kernels.
For arch maintainers there are some simple tests to be able to quickly
verify that the syscalls are working correctly here:
http://ozlabs.org/~cyeoh/cma/cma-test-20110718.tgz
Signed-off-by: Chris Yeoh <yeohc@au1.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Howells <dhowells@redhat.com>
Cc: James Morris <jmorris@namei.org>
Cc: <linux-man@vger.kernel.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
