This fixes three issues noticed by Arnd Bergmann:

- Add #ifdef __KERNEL__ and move some things around in perf_counter.h
  to make sure only the bits that userspace needs are exported to
  userspace.

- Use __u64, __s64, __u32 types in the structs exported to userspace
  rather than u64, s64, u32.

- Make the sys_perf_counter_open syscall available to the SPUs on
  Cell platforms.

And one issue that I noticed in looking at the code again:

- Wrap the perf_counter_open syscall with SYSCALL_DEFINE4 so we get
  the proper handling of int arguments on ppc64 (and some other 64-bit
  architectures).
Reported-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Impact: fix build error

to fix:

  tip/arch/ia64/kernel/acpi.c:203: error: conflicting types for '__acpi_unmap_table'
  tip/include/linux/acpi.h:82: error: previous declaration of '__acpi_unmap_table' was here
  tip/arch/ia64/kernel/acpi.c:203: error: conflicting types for '__acpi_unmap_table'
  tip/include/linux/acpi.h:82: error: previous declaration of '__acpi_unmap_table' was here
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Cc: Jeremy Fitzhardinge <jeremy@goop.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Jaswinder Singh Rajput reported that commit 23a185ca caused the
context switch and migration software counters to report zero always.
With that commit, the software counters only count events that occur
between sched-in and sched-out for a task.  This is necessary for the
counter enable/disable prctls and ioctls to work.  However, the
context switch and migration counts are incremented after sched-out
for one task and before sched-in for the next.  Since the increment
doesn't occur while a task is scheduled in (as far as the software
counters are concerned) it doesn't count towards any counter.

Thus the context switch and migration counters need to count events
that occur at any time, provided the counter is enabled, not just
those that occur while the task is scheduled in (from the perf_counter
subsystem's point of view).  The problem though is that the software
counter code can't tell the difference between being enabled and being
scheduled in, and between being disabled and being scheduled out,
since we use the one pair of enable/disable entry points for both.
That is, the high-level disable operation simply arranges for the
counter to not be scheduled in any more, and the high-level enable
operation arranges for it to be scheduled in again.

One way to solve this would be to have sched_in/out operations in the
hw_perf_counter_ops struct as well as enable/disable.  However, this
takes a simpler approach: it adds a 'prev_state' field to the
perf_counter struct that allows a counter's enable method to know
whether the counter was previously disabled or just inactive
(scheduled out), and therefore whether the enable method is being
called as a result of a high-level enable or a schedule-in operation.

This then allows the context switch, migration and page fault counters
to reset their hw.prev_count value in their enable functions only if
they are called as a result of a high-level enable operation.
Although page faults would normally only occur while the counter is
scheduled in, this changes the page fault counter code too in case
there are ever circumstances where page faults get counted against a
task while its counters are not scheduled in.
Reported-by: NJaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With the new system call defines we get this on uml:

arch/um/sys-i386/built-in.o: In function `sys_call_table':
(.rodata+0x308): undefined reference to `sys_sigprocmask'

Reason for this is that uml passes the preprocessor option
-Dsigprocmask=kernel_sigprocmask to gcc when compiling the kernel.
This causes SYSCALL_DEFINE3(sigprocmask, ...) to be expanded to
SYSCALL_DEFINEx(3, kernel_sigprocmask, ...) and finally to a system
call named sys_kernel_sigprocmask.  However sys_sigprocmask is missing
because of this.

To avoid macro expansion for the system call name just concatenate the
name at first define instead of carrying it through severel levels.
This was pointed out by Al Viro.
Signed-off-by: NHeiko Carstens <heiko.carstens@de.ibm.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: NWANG Cong <wangcong@zeuux.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I enabled all cgroup subsystems when compiling kernel, and then:
 # mount -t cgroup -o net_cls xxx /mnt
 # mkdir /mnt/0

This showed up immediately:
 BUG: MAX_LOCKDEP_SUBCLASSES too low!
 turning off the locking correctness validator.

It's caused by the cgroup hierarchy lock:
	for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
		struct cgroup_subsys *ss = subsys[i];
		if (ss->root == root)
			mutex_lock_nested(&ss->hierarchy_mutex, i);
	}

Now we have 9 cgroup subsystems, and the above 'i' for net_cls is 8, but
MAX_LOCKDEP_SUBCLASSES is 8.

This patch uses different lockdep keys for different subsystems.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NPaul Menage <menage@google.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Ptrace_detach() races with __ptrace_unlink() if the traced task is
reaped while detaching. This might cause a double-free of the BTS
buffer.

Change the ptrace_detach() path to only do the memory accounting in
ptrace_bts_detach() and leave the buffer free to ptrace_bts_untrace()
which will be called from __ptrace_unlink().

The fix follows a proposal from Oleg Nesterov.
Reported-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NMarkus Metzger <markus.t.metzger@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The POSIX timer interface allows for absolute time expiry values through the
TIMER_ABSTIME flag, therefore we have to synchronize the timer to the clock
every time we start it.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

To decrease the chance of a missed enable, always enable the timer when we
sample it, we'll always disable it when we find that there are no active timers
in the jiffy tick.

This fixes a flood of warnings reported by Mike Galbraith.
Reported-by: NMike Galbraith <efault@gmx.de>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: new perf_counter feature

This extends the perf_counter_hw_event struct with bits that specify
that events in user, kernel and/or hypervisor mode should not be
counted (i.e. should be excluded), and adds code to program the PMU
mode selection bits accordingly on x86 and powerpc.

For software counters, we don't currently have the infrastructure to
distinguish which mode an event occurs in, so we currently fail the
counter initialization if the setting of the hw_event.exclude_* bits
would require us to distinguish.  Context switches and CPU migrations
are currently considered to occur in kernel mode.

On x86, this changes the previous policy that only root can count
kernel events.  Now non-root users can count kernel events or exclude
them.  Non-root users still can't use NMI events, though.  On x86 we
don't appear to have any way to control whether hypervisor events are
counted or not, so hw_event.exclude_hv is ignored.

On powerpc, the selection of whether to count events in user, kernel
and/or hypervisor mode is PMU-wide, not per-counter, so this adds a
check that the hw_event.exclude_* settings are the same as other events
on the PMU.  Counters being added to a group have to have the same
settings as the other hardware counters in the group.  Counters and
groups can only be enabled in hw_perf_group_sched_in or power_perf_enable
if they have the same settings as any other counters already on the
PMU.  If we are not running on a hypervisor, the exclude_hv setting
is ignored (by forcing it to 0) since we can't ever get any
hypervisor events.
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Using u32 in this header breaks the build of iptables.
Signed-off-by: NChuck Ebbert <cebbert@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix regression due to 5a6fe125,
"Do not account for the address space used by hugetlbfs using VM_ACCOUNT"
which added an argument to the function hugetlb_file_setup() but not to
the macro hugetlb_file_setup().
Reported-by: NChris Clayton <chris2553@googlemail.com>
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When overcommit is disabled, the core VM accounts for pages used by anonymous
shared, private mappings and special mappings. It keeps track of VMAs that
should be accounted for with VM_ACCOUNT and VMAs that never had a reserve
with VM_NORESERVE.

Overcommit for hugetlbfs is much riskier than overcommit for base pages
due to contiguity requirements. It avoids overcommiting on both shared and
private mappings using reservation counters that are checked and updated
during mmap(). This ensures (within limits) that hugepages exist in the
future when faults occurs or it is too easy to applications to be SIGKILLed.

As hugetlbfs makes its own reservations of a different unit to the base page
size, VM_ACCOUNT should never be set. Even if the units were correct, we would
double account for the usage in the core VM and hugetlbfs. VM_NORESERVE may
be set because an application can request no reserves be made for hugetlbfs
at the risk of getting killed later.

With commit fc8744ad, VM_NORESERVE and
VM_ACCOUNT are getting unconditionally set for hugetlbfs-backed mappings. This
breaks the accounting for both the core VM and hugetlbfs, can trigger an
OOM storm when hugepage pools are too small lockups and corrupted counters
otherwise are used. This patch brings hugetlbfs more in line with how the
core VM treats VM_NORESERVE but prevents VM_ACCOUNT being set.
Signed-off-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

ELF core dump is used for both user land core dump and kernel crash
dump.  Depending on architecture, register might need to be accessed
differently for userland and kernel.  Allow architectures to define
ELF_CORE_COPY_KERNEL_REGS() and use different operation for kernel
register dump.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Removed OSSlib stuff from linux/soundcard.h to fix the warnings for
'make headers_check'.

This patch breaks building against OSSlib with the kernel headers
instead of its own headers. It should still work with any
version of the library from the 2003 onwards which provide
their own headers for the latest interface.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Jaswinder Singh Rajput <jaswinder@kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Architectures other than mips and x86 are not using ticket spinlocks.
Therefore, the contention on the lock is meaningless, since there is
nobody known to be waiting on it (arguably /fairly/ unfair locks).

Dummy it out to return 0 on other architectures.
Signed-off-by: NKyle McMartin <kyle@redhat.com>
Acked-by: NRalf Baechle <ralf@linux-mips.org>
Acked-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

to prevent wrongly overwriting fixmap that still want to use.

ACPI used to rely on low mappings being all linearly mapped and
grew a habit: it never really unmapped certain kinds of tables
after use.

This can cause problems - for example the hypothetical case
when some spurious access still references it.

v2: remove prev_map and prev_size in __apci_map_table
v3: let acpi_os_unmap_memory() call early_iounmap too, so remove extral calling to
early_acpi_os_unmap_memory
v4: fix typo in one acpi_get_table_with_size calling
Signed-off-by: NYinghai Lu <yhlu.kernel@gmail.com>
Acked-by: NLen Brown <len.brown@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: kernel crash fix

Yanmin Zhang reported that using a PERF_COUNT_TASK_CLOCK software
counter as a per-cpu counter would reliably crash the system, because
it calls __task_delta_exec with a null pointer.  The page fault,
context switch and cpu migration counters also won't function
correctly as per-cpu counters since they reference the current task.

This fixes the problem by redirecting the task_clock counter to the
cpu_clock counter when used as a per-cpu counter, and by implementing
per-cpu page fault, context switch and cpu migration counters.

Along the way, this:

- Initializes counter->ctx earlier, in perf_counter_alloc, so that
  sw_perf_counter_init can use it
- Adds code to kernel/sched.c to count task migrations into each
  cpu, in rq->nr_migrations_in
- Exports the per-cpu context switch and task migration counts
  via new functions added to kernel/sched.c
- Makes sure that if sw_perf_counter_init fails, we don't try to
  initialize the counter as a hardware counter.  Since the user has
  passed a negative, non-raw event type, they clearly don't intend
  for it to be interpreted as a hardware event.
Reported-by: N"Zhang Yanmin" <yanmin_zhang@linux.intel.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: bug fix

IA-64 needs to put percpu data in the seperate section even on UP.
Fixes regression caused by "percpu: refactor percpu.h"
Signed-off-by: NBrian Gerst <brgerst@gmail.com>
Acked-by: NTony Luck <tony.luck@intel.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Rename the async_*_special() functions to async_*_domain(), which
describes the purpose of these functions much better.
[Broke up long lines to silence checkpatch]
Signed-off-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>

Reported-by: NSam Ravnborg <sam@ravnborg.org>
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

Impact: fix spurious BUG_ON() triggered under load

module_refcount() isn't reliable outside stop_machine(), as demonstrated
by Karsten Keil <kkeil@suse.de>, networking can trigger it under load
(an inc on one cpu and dec on another while module_refcount() is tallying
 can give false results, for example).

Almost noone should be using __module_get, but that's another issue.

Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Based upon a patch from Atsushi Nemoto <anemo@mba.ocn.ne.jp>

--------------------
The commit 649274d9 ("net_dma:
acquire/release dma channels on ifup/ifdown") added unconditional call
of dmaengine_get() to net_dma.  The API should be called only if
NET_DMA was enabled.
--------------------
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NDan Williams <dan.j.williams@intel.com>

Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

Mike Galbraith reported that the new warning in thread_group_cputimer()
triggers en masse with Amarok running.

Oleg Nesterov observed:

  Can't fastpath_timer_check()->thread_group_cputimer() have the
  false warning too? Suppose we had the timer, then posix_cpu_timer_del()
  removes this timer, but task_cputime_zero(&sig->cputime_expires) still
  not true.

Remove the spurious debug warning.
Reported-by: NMike Galbraith <efault@gmx.de>
Explained-by: NOleg Nesterov <oleg@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

This function should be provided on UP too.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

disable_ioapic_setup() in init/main.c is ugly as the function is
x86-specific. The #ifdef inline prototype there is ugly too.

Replace it with a generic arch_disable_smp_support() function - which
has a weak alias for non-x86 architectures and for non-ioapic x86 builds.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

With exclusive waiters, every process woken up through the wait queue must
ensure that the next waiter down the line is woken when it has finished.

Interruptible waiters don't do that when aborting due to a signal.  And if
an aborting waiter is concurrently woken up through the waitqueue, noone
will ever wake up the next waiter.

This has been observed with __wait_on_bit_lock() used by
lock_page_killable(): the first contender on the queue was aborting when
the actual lock holder woke it up concurrently.  The aborted contender
didn't acquire the lock and therefor never did an unlock followed by
waking up the next waiter.

Add abort_exclusive_wait() which removes the process' wait descriptor from
the waitqueue, iff still queued, or wakes up the next waiter otherwise.
It does so under the waitqueue lock.  Racing with a wake up means the
aborting process is either already woken (removed from the queue) and will
wake up the next waiter, or it will remove itself from the queue and the
concurrent wake up will apply to the next waiter after it.

Use abort_exclusive_wait() in __wait_event_interruptible_exclusive() and
__wait_on_bit_lock() when they were interrupted by other means than a wake
up through the queue.

[akpm@linux-foundation.org: coding-style fixes]
Reported-by: NChris Mason <chris.mason@oracle.com>
Signed-off-by: NJohannes Weiner <hannes@cmpxchg.org>
Mentored-by: NOleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Chuck Lever <cel@citi.umich.edu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: <stable@kernel.org>		["after some testing"]
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Avoid calling copy_from/to_user() with fb_info->lock mutex held in fbmem
ioctl().

fb_mmap() is called under mm->mmap_sem (A) held, that also acquires
fb_info->lock (B); fb_ioctl() takes fb_info->lock (B) and does
copy_from/to_user() that might acquire mm->mmap_sem (A), causing a
deadlock.

NOTE: it doesn't push down the fb_info->lock in each own driver's
fb_ioctl(), so there are still potential deadlocks elsewhere.
Signed-off-by: NAndrea Righi <righi.andrea@gmail.com>
Cc: Dave Jones <davej@redhat.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Johannes Weiner <hannes@saeurebad.de>
Cc: Krzysztof Helt <krzysztof.h1@wp.pl>
Cc: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The swap() macro is accidentally retuning the value of its first argument.
Change it into a doesn't-return-anything macro before someone goes and
relies upon this behaviour.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wu Fengguang <wfg@linux.intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Change the process wide cpu timers/clocks so that we:

 1) don't mess up the kernel with too many threads,
 2) don't have a per-cpu allocation for each process,
 3) have no impact when not used.

In order to accomplish this we're going to split it into two parts:

 - clocks; which can take all the time they want since they run
           from user context -- ie. sys_clock_gettime(CLOCK_PROCESS_CPUTIME_ID)

 - timers; which need constant time sampling but since they're
           explicity used, the user can pay the overhead.

The clock readout will go back to a full sum of the thread group, while the
timers will run of a global 'clock' that only runs when needed, so only
programs that make use of the facility pay the price.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

We're going to split the process wide cpu accounting into two parts:

 - clocks; which can take all the time they want since they run
           from user context.

 - timers; which need constant time tracing but can affort the overhead
           because they're default off -- and rare.

The clock readout will go back to a full sum of the thread group, for this
we need to re-add the exit stats that were removed in the initial itimer
rework (f06febc9: timers: fix itimer/many thread hang).

Furthermore, since that full sum can be rather slow for large thread groups
and we have the complete dead task stats, revert the do_notify_parent time
computation.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Geert Uytterhoeven pointed out that we're not zeroing all the
memory when freeing a transform.  This patch fixes it by calling
ksize to ensure that we zero everything in sight.
Reported-by: NGeert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch makes the ROM reading code return an error to user space if
the size of the ROM read is equal to 0.

The patch also emits a warnings if the contents of the ROM are invalid,
and documents the effects of the "enable" file on ROM reading.
Signed-off-by: NTimothy S. Nelson <wayland@wayland.id.au>
Acked-by: NAlex Villacis-Lasso <a_villacis@palosanto.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

Only REISERFS_IOC_* definitions are required for user space
rest should be in #ifdef __KERNEL__ as pointed by Arnd Bergmann.
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

These are only for kernel internals as pointed by Arnd Bergmann:
   struct nubus_board
   struct nubus_dev
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

These are only for kernel internals as pointed by Arnd Bergmann:
  struct kstatfs
  struct venus_comm
  coda_vcp()
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>

Add kernel-doc notation for @lock:

include/linux/sched.h:457: No description found for parameter 'lock'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

3Gbps is often much more prone to transmission failures.  It's usually
okay to let EH handle speed down after transmission failures but some
WD My Book drives completely shutdown after certain transmission
failures and after it only power cycling can revive them.  Combined
with the fact that external drives often end up with cable assembly
which is longer than usual and more likely to have intervening gender,
this makes these drives very likely to shutdown under certain
configurations virtually rendering them unusable.

This patch implements HOARKGE_1_5_GBPS and applies it to WD My Book
such that 1.5Gbps is forced once the device is identified.

Please take a look at the following bz for related reports.

  http://bugzilla.kernel.org/show_bug.cgi?id=9913Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

dev->ering used to be cleared together with the rest of ata_device in
ata_dev_init() which is called whenever a probing event occurs.
dev->ering is about to be used to track probing failures so it needs
to remain persistent over multiple porbing events.  This patch
achieves this by doing the following.

* Instead of CLEAR_OFFSET, define CLEAR_BEGIN and CLEAR_END and only
  clear between BEGIN and END.  ering is moved after END.  The split
  of persistent area is to allow hotter items remain at the head.

* ering is explicitly cleared on ata_dev_disable() and when device
  attach succeeds.  So, ering is persistent throug a device's life
  time (unless explicitly cleared of course) and also through periods
  inbetween disablement of an attached device and successful detection
  of the next one.
Signed-off-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

When checking for the CFA feature set support, ata_id_is_cfa() tests bit 2 in
word 82 of the identify data instead the word 83;  it also checks the ATA/PI
version support in the word 80 (which the CompactFlash specifications have as
reserved), this having no slightest chance to work on the modern CF cards that
don't have 0x848A in the word 0...
Signed-off-by: NSergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>