This patch adds a field in pv_cpu_ops for a paravirtualized hook
for rdtscp, needed for x86_64.
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch changes paravirt_32.c to paravirt.c. The goal
is to have paravirt support in x86_64, so we do it in a common file
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Pass the buffer size for (most) ptrace commands that pass user-allocated buffers and check that size before accessing the buffer. Unfortunately, PTRACE_BTS_GET already uses all 4 parameters.
Commands that access user buffers return the number of bytes or records read or written.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Support BTS recording of 32bit and 64bit tasks from 32bit or 64bit tasks.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Check the rlimit of the tracing task for total and locked memory when allocating the BTS buffer.
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Move some deeply indented code related to re-entrance processing
from kprobe_handler() to reenter_kprobe().
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ mhiramat@redhat.com: updated it to latest x86.git ]
Factor common X86_32, X86_64 kprobe reenter logic from deeply
indented section to helper function.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Fix a preemption bug in kprobe_handler(). It has to call preempt_enable()
before returning.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Aviod TLB flush IPIs during C3 states by voluntary leave_mm()
before entering C3.
The performance impact of TLB flush on C3 should not be significant with
respect to C3 wakeup latency. Also, CPUs tend to flush TLB in hardware while in
C3 anyways.
On a 8 logical CPU system, running make -j2, the number of tlbflush IPIs goes
down from 40 per second to ~ 0. Total number of interrupts during the run
of this workload was ~1200 per second, which makes it ~3% savings in wakeups.
There was no measurable performance or power impact however.
[ akpm@linux-foundation.org: symbol export fixes. ]
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
we use a few static mapping rules in our pirq routing functions,
and for example regression f3ac84324f was due to the pirq
being out of range of the remapping array. Put in a few
WARN_ON_ONCE() lines so that we get notified about any such
out-of-bound incidents.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
increasing number of PCI slots in large multi-node systems. The kernel
currently attempts by default to allocate memory for all PCI expansion
ROMs so there has also been an increasing number of PCI memory
allocation failures seen on these systems. This occurs because the BIOS
either (1) provides insufficient PCI memory resource for all the
expansion ROMs or (2) provides adequate PCI memory resource for
expansion ROMs but provides the space in kernel unexpected BIOS assigned
P2P non-prefetch windows.
The resulting PCI memory allocation failures may be benign when related
to memory requests for expansion ROMs themselves but in some cases they
can occur when attempting to allocate space for more critical BARs.
This can happen when a successful expansion ROM allocation request
consumes memory resource that was intended for a non-ROM BAR. We have
seen this happen during PCI hotplug of an adapter that contains a P2P
bridge where successful memory allocation for an expansion ROM BAR on
device behind the bridge consumed memory that was intended for a non-ROM
BAR on the P2P bridge. In all cases the allocation failure messages can
be very confusing for users.
This patch addresses the issue by changing the kernel default behavior
so that expansion ROM memory allocations are no longer attempted by
default when the BIOS has not assigned a specific address range to the
expansion ROM BAR. This was done by changing the 'pci=rom' boot option
behavior for BIOS unassigned expansion ROMs to actually match it's
current kernel-parameters.txt description which already implies "off" by
default. Behavior for BIOS assigned expansion ROMs implemented in
pcibios_assign_resources() [arch/x86/pci/i386.c] is unchanged.
Signed-off-by: Gary Hade <garyhade@us.ibm.com>
Cc: Greg KH <greg@kroah.com>
Cc: Jan Beulich <jbeulich@novell.com>
Acked-by: "Jun'ichi Nomura" <j-nomura@ce.jp.nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This removes duplicated code by calling the generic ptrace_request and
compat_ptrace_request functions for the things they already handle.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This makes ELF core dumps of 32-bit processes include a new
note type NT_386_TLS (0x200) giving the contents of the TLS
slots in struct user_desc format. This lets post mortem
examination figure out what the segment registers mean like
the debugger does with get_thread_area on a live process.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Remove the old ia32_binfmt.c file, which is no longer used.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This switches x86-64's 32-bit ELF support to use the shared
fs/compat_binfmt_elf.c code instead of our own ia32_binfmt.c.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This removes a bunch of dead code that is no longer needed now
that the user_regset interfaces are being used for all these jobs.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This cleans up the PTRACE_*REGS* request code so each one is just a
simple call to copy_regset_to_user or copy_regset_from_user. The
ptrace layouts already match the user_regset formats (core dump formats).
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This defines task_user_regset_view and the tables
describing the x86 user_regset layouts for 32 and 64.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This adds accessor functions in the user_regset style for
the general registers (struct user_regs_struct).
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This adds accessor functions in the user_regset style for the TLS data.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This cleans up the TLS code to use struct desc_struct and to separate the
encoding and installation magic from the interface wrappers.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This removes all the old code that is no longer used after
the i387 unification and cleanup. The i387_64.h is renamed
to i387.h with no changes, but since it replaces the nonempty
one-line stub i387.h it looks like a big diff and not a rename.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This revamps the i387 code to be shared across 32-bit, 64-bit,
and 32-on-64. It does so by consolidating the code in one place
based on the user_regset accessor interfaces. This switches
32-bit to using the i387_64.h header and 64-bit to using the
i387.c that was previously i387_32.c, but that's what took the
least cleanup in each file. Here i387.h is stubbed to always
include i387_64.h rather than renaming the file, to keep this
diff smaller and easier to read.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This renames arch/x86/kernel/{i387_32.c => i387.c}.
This is a pure renaming, but paves the way for merging
the 32-bit and 64-bit versions of this code.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This converts the ptrace/signal accessors for i387 math_emu
state to the user_regset interface style, and calls these
from the old interfaces.
It also cleans up math_emulate's ptrace check to be a
single-step check, which is what it really wants.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This moves some code into asm-x86/i387_64.h in preparation for
unifying this code between 32 and 64. The 32-bit versions of
some things are copied in some existing names changed to match
32-bit names and share code. For 64, save_i387 is moved into
an inline from i387_64.c; this matches restore_i387, which is
already an inline, and makes sense since there is exactly one
caller (in signal_64.c). The save_i387 function could use more
cosmetic cleanup, but it is just moved verbatim in this patch.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Eliminate __always_inline, all of these static functions are
only called once. Minor whitespace cleanup. Eliminate one
supefluous return at end of void function. Change the one
#ifndef to #ifdef to match the sense of the rest of the config
tests.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Acked-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Use the fixup_exception() helper in fault_64.c
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Introduce fixup_exception() on 64-bit and use it in kprobes to
eliminate an #ifdef.
Only 64-bit needs search_extable() due to a stepping bug.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch moves definitions that are present in only one of the files
(between processor_32.h and processor_64.h), to processor.h. They're mostly
structures and function definitions.
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
x86_cpuinfo is one more to the family of "not fundamentally different"
structs. It's unified in processor.h, with very specific fields enclosed
around ifdefs.
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Paravirt guests need to inform the underlying hypervisor whenever the sp0
tss field changes. i386 already has such a function, and we use it for
x86_64 too. There's an unnecessary (for 64-bit) msr handling part in the original
version, and it is placed around an ifdef. Making no more sense in
processor_32.h, it is moved to the common header
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Although slighly different, the tss_struct is very similar in x86_64 and
i386. The really different part, which matchs the hardware vision of it, is
now called x86_hw_tss, and each of the architectures provides yours.
It's then used as a field in the outter tss_struct.
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There's no need for the *_MASK flags (TF_MASK, IF_MASK, etc), found in
processor.h (both _32 and _64). They have a one-to-one mapping with the
EFLAGS value. This patch removes the definitions, and use the already
existent X86_EFLAGS_ version when applicable.
[ roland@redhat.com: KVM build fixes. ]
Signed-off-by: Glauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
clean up checkpatch warnings/errors on i387_32.c
The old and new i387_32.s (asm listings) were checked with diff to
be identical so it's safe to apply this patch.
Signed-off-by: Cyrill Gorcunov <gorunov@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Recently a kdump bug was discovered in which a system would hang inside
calibrate_delay during the booting of the kdump kernel. This was caused
by the fact that the jiffies counter was not being incremented during
timer calibration. The root cause of this problem was found to be a
bios misconfiguration of the hypertransport bus. On system affected by
this hang, the bios had assigned APIC ids which used extended apic bits
(more than the nominal 4 bit ids's), but failed to configure bit 17 of
the hypertransport transaction config register, which indicated that the
mask for the destination field of interrupt packets accross the ht bus
(see section 3.3.9 of
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/26094.PDF).
If a crash occurs on a cpu with an APIC id that extends beyond 4 bits,
it will not recieve interrupts during the kdump kernel boot, and this
hang will be the result. The fix is to add this patch, whcih add an
early pci quirk check, to forcibly enable this bit in the httcfg
register. This enables all cpus on a system to receive interrupts, and
allows kdump kernel bootup to procede normally.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Its previous use in a call to on_each_cpu() was pointless, as at the
time that code gets executed only one CPU is online. Further, the
function can be __cpuinit, and for this to work without
CONFIG_HOTPLUG_CPU setup_nmi() must also get an attribute (this one
can even be __init; on 64-bits check_timer() also was lacking that
attribute).
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
.. allowing to remove their declarations from a global include file
(the symbols don't exist for anything but x86).
Likewise for 64-bits' fix_processor_context(), just that that one was
properly declared in an arch-specific header.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The array is never written, and on 64-bits it's not even being used
past initial boot.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This requires making die() return a value, making its callers honor
this (and be prepared that it may return), and making oops_end() have
two additional parameters.
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch unifies kprobes code.
- Unify kprobes_*.h to kprobes.h
- Unify kprobes_*.c to kprobes.c
(Differences are separated by ifdefs)
- Most differences are related to REX prefix and rip relatives.
- Two inline assembly code are different.
- One difference in kprobe_handlre()
- One fixup exception code is different, but it will be unified
if mm/extable_*.c are unified.
- Merge history logs into arch/x86/kernel/kprobes.c.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch cleanup kprobes code on x86 for unification.
This patch is based on Arjan's previous work.
- Remove spurious whitespace changes
- Add harmless includes
- Make the 32/64 files more identical
- Generalize structure fields' and local variable name.
- Wrap accessing to stack address by macros.
- Modify bitmap making macro.
- Merge fixup code into is_riprel() and change its name to fix_riprel().
- Set MAX_INSN_SIZE to 16 on both arch.
- Use u32 for bitmaps on both architectures.
- Clarify some comments.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds kretprobe-booster to kprobes_64.c.
- Changes are based on x86-32.
- Rewrite register saving/restoring code
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch adds kprobe-booster to kprobes_64.c.
- Changes are based on x86-32.
- Add REX prefix checking code.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: Jim Keniston <jkenisto@us.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Introduce ticket lock spinlocks for x86 which are FIFO. The implementation
is described in the comments. The straight-line lock/unlock instruction
sequence is slightly slower than the dec based locks on modern x86 CPUs,
however the difference is quite small on Core2 and Opteron when working out of
cache, and becomes almost insignificant even on P4 when the lock misses cache.
trylock is more significantly slower, but they are relatively rare.
On an 8 core (2 socket) Opteron, spinlock unfairness is extremely noticable,
with a userspace test having a difference of up to 2x runtime per thread, and
some threads are starved or "unfairly" granted the lock up to 1 000 000 (!)
times. After this patch, all threads appear to finish at exactly the same
time.
The memory ordering of the lock does conform to x86 standards, and the
implementation has been reviewed by Intel and AMD engineers.
The algorithm also tells us how many CPUs are contending the lock, so
lockbreak becomes trivial and we no longer have to waste 4 bytes per
spinlock for it.
After this, we can no longer spin on any locks with preempt enabled
and cannot reenable interrupts when spinning on an irq safe lock, because
at that point we have already taken a ticket and the would deadlock if
the same CPU tries to take the lock again. These are questionable anyway:
if the lock happens to be called under a preempt or interrupt disabled section,
then it will just have the same latency problems. The real fix is to keep
critical sections short, and ensure locks are reasonably fair (which this
patch does).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The break_lock data structure and code for spinlocks is quite nasty.
Not only does it double the size of a spinlock but it changes locking to
a potentially less optimal trylock.
Put all of that under CONFIG_GENERIC_LOCKBREAK, and introduce a
__raw_spin_is_contended that uses the lock data itself to determine whether
there are waiters on the lock, to be used if CONFIG_GENERIC_LOCKBREAK is
not set.
Rename need_lockbreak to spin_needbreak, make it use spin_is_contended to
decouple it from the spinlock implementation, and make it typesafe (rwlocks
do not have any need_lockbreak sites -- why do they even get bloated up
with that break_lock then?).
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Here's the new ptrace BTS API that supports two different overflow handling mechanisms (wrap-around and buffer-full-signal) to support two different use cases (debugging and profiling).
It further combines buffer allocation and configuration.
Opens:
- memory rlimit
- overflow signal
What would be the right signal to use?
Signed-off-by: Markus Metzger <markus.t.metzger@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>