Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* no allocations
* return void
* don't duplicate checked for dummy context
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* no allocations
* return void
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* don't bother with allocations
* don't do double copy_from_user()
* don't duplicate parts of check for audit_dummy_context()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* logging the original value of *msg_prio in mq_timedreceive(2)
  is insane - the argument is write-only (i.e. syscall always
  ignores the original value and only overwrites it).
* merge __audit_mq_timed{send,receive}
* don't do copy_from_user() twice
* don't mess with allocations in auditsc part
* ... and don't bother checking !audit_enabled and !context in there -
  we'd already checked for audit_dummy_context().
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* don't copy_from_user() twice
* don't bother with allocations
* don't duplicate parts of audit_dummy_context()
* make it return void
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* get rid of allocations
* make it return void
* don't duplicate parts of audit_dummy_context()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* get rid of allocations
* make it return void
* simplify callers
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* get rid of allocations
* make it return void
* simplify callers
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

* don't bother with allocations
* now that it can't fail, make it return void
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

No need to do that more than once per process lifetime; allocating/freeing
on each sendto/accept/etc. is bloody pointless.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Impact: prevents panic from stack overflow on numa-capable machines.

Some of the "removal of stack hogs" changes in kernel/sched.c by using
node_to_cpumask_ptr were undone by the early cpumask API updates, and
causes a panic due to stack overflow.  This patch undoes those changes
by using cpumask_of_node() which returns a 'const struct cpumask *'.

In addition, cpu_coregoup_map is replaced with cpu_coregroup_mask further
reducing stack usage.  (Both of these updates removed 9 FIXME's!)

Also:
   Pick up some remaining changes from the old 'cpumask_t' functions to
   the new 'struct cpumask *' functions.

   Optimize memory traffic by allocating each percpu local_cpu_mask on the
   same node as the referring cpu.
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: build fix on ia64

ia64's default_affinity_write() still had old cpumask_t usage:

 /home/mingo/tip/kernel/irq/proc.c: In function `default_affinity_write':
 /home/mingo/tip/kernel/irq/proc.c:114: error: incompatible type for argument 1 of `is_affinity_mask_valid'
 make[3]: *** [kernel/irq/proc.o] Error 1
 make[3]: *** Waiting for unfinished jobs....

update it to cpumask_var_t.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

This warning:

 kernel/rcuclassic.c: In function ‘rcu_start_batch’:
 kernel/rcuclassic.c:397: warning: passing argument 1 of ‘cpumask_andnot’ from incompatible pointer type

triggers because one usage site of rcp->cpumask was not converted
to to_cpumask(rcp->cpumask). There's no ill effects of this bug.
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: cleanup

Simple replacement, now the _nr is redundant.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: Ingo Molnar <mingo@redhat.com>

Impact: Reduce stack usage, use new cpumask API.

Mainly changing cpumask_t to 'struct cpumask' and similar simple API
conversion.  Two conversions worth mentioning:

1) we use cpumask_any_but to avoid a temporary in kernel/softlockup.c,
2) Use cpumask_var_t in taskstats_user_cmd().
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>

Impact: Reduce kernel stack and memory usage, use new cpumask API.

Use cpumask_var_t for take_cpu_down() stack var, and frozen_cpus.

Note that notify_cpu_starting() can be called before core_initcall
allocates frozen_cpus, but the NULL check is optimized out by gcc for
the CONFIG_CPUMASK_OFFSTACK=n case.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Reduce kernel memory usage, use new cpumask API.

Avoid a static cpumask_t for prof_cpu_mask, and an on-stack cpumask_t
in prof_cpu_mask_write_proc.  Both become cpumask_var_t.

prof_cpu_mask is only allocated when profiling is on, but the NULL
checks are optimized out by gcc for the !CPUMASK_OFFSTACK case.

Also removed some strange and unnecessary casts.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: use new cpumask API.

rcu_ctrlblk contains a cpumask, and it's highly optimized so I don't want
a cpumask_var_t (ie. a pointer) for the CONFIG_CPUMASK_OFFSTACK case.  It
could use a dangling bitmap, and be allocated in __rcu_init to save memory,
but for the moment we use a bitmap.

(Eventually 'struct cpumask' will be undefined for CONFIG_CPUMASK_OFFSTACK,
so we use a bitmap here to show we really mean it).

We remove on-stack cpumasks, using cpumask_var_t for
rcu_torture_shuffle_tasks() and for_each_cpu_and in force_quiescent_state().
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Reduce stack usage, use new cpumask API.  ALPHA mod!

Main change is that irq_default_affinity becomes a cpumask_var_t, so
treat it as a pointer (this effects alpha).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Use new APIs

Convert kernel/time functions to use struct cpumask *.

Note the ugly bitmap declarations in tick-broadcast.c.  These should
be cpumask_var_t, but there was no obvious initialization function to
put the alloc_cpumask_var() calls in.  This was safe.

(Eventually 'struct cpumask' will be undefined for CONFIG_CPUMASK_OFFSTACK,
so we use a bitmap here to show we really mean it).
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>

Impact: Reduce memory usage, use new cpumask API.

cpu_populated_map becomes a cpumask_var_t, and cpu_singlethread_map is
simply a cpumask pointer: it's simply the cpumask containing the first
possible CPU anyway.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Reduce stack usage, use new cpumask API.

Straightforward conversion; cpumasks' size is given by cpumask_size() (now
a variable rather than fixed) and on-stack cpu masks use cpumask_var_t.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Remove obsolete API usage

any_online_cpu() is a good name, but it takes a cpumask_t, not a
pointer.

There are several places where any_online_cpu() doesn't really want a
mask arg at all.  Replace all callers with cpumask_any() and
cpumask_any_and().
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>

Impact: Reduce future memory usage, use new cpumask API.

Since the last patch was created and acked, more old cpumask users
slipped into kernel/trace.

Mostly trivial conversions, except struct trace_iterator's "started"
member becomes a cpumask_var_t.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Reduce future memory usage, use new cpumask API.

(Eventually, cpumask_var_t will be allocated based on nr_cpu_ids, not NR_CPUS).

Convert kernel trace functions to use struct cpumask API:
1) Use cpumask_copy/cpumask_test_cpu/for_each_cpu.
2) Use cpumask_var_t and alloc_cpumask_var/free_cpumask_var everywhere.
3) Use on_each_cpu instead of playing with current->cpus_allowed.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NSteven Rostedt <rostedt@goodmis.org>

Impact: cleanup

In future, all cpumask ops will only be valid (in general) for bit
numbers < nr_cpu_ids.  So use that instead of NR_CPUS in iterators
and other comparisons.

This is always safe: no cpu number can be >= nr_cpu_ids, and
nr_cpu_ids is initialized to NR_CPUS at boot.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Acked-by: NIngo Molnar <mingo@elte.hu>
Acked-by: NJames Morris <jmorris@namei.org>
Cc: Eric Biederman <ebiederm@xmission.com>

The cpu time spent by the idle process actually doing something is
currently accounted as idle time. This is plain wrong, the architectures
that support VIRT_CPU_ACCOUNTING=y can do better: distinguish between the
time spent doing nothing and the time spent by idle doing work. The first
is accounted with account_idle_time and the second with account_system_time.
The architectures that use the account_xxx_time interface directly and not
the account_xxx_ticks interface now need to do the check for the idle
process in their arch code. In particular to improve the system vs true
idle time accounting the arch code needs to measure the true idle time
instead of just testing for the idle process.
To improve the tick based accounting as well we would need an architecture
primitive that can tell us if the pt_regs of the interrupted context
points to the magic instruction that halts the cpu.

In addition idle time is no more added to the stime of the idle process.
This field now contains the system time of the idle process as it should
be. On systems without VIRT_CPU_ACCOUNTING this will always be zero as
every tick that occurs while idle is running will be accounted as idle
time.

This patch contains the necessary common code changes to be able to
distinguish idle system time and true idle time. The architectures with
support for VIRT_CPU_ACCOUNTING need some changes to exploit this.
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

The utimescaled / stimescaled fields in the task structure and the
global cpustat should be set on all architectures. On s390 the calls
to account_user_time_scaled and account_system_time_scaled never have
been added. In addition system time that is accounted as guest time
to the user time of a process is accounted to the scaled system time
instead of the scaled user time.
To fix the bugs and to prevent future forgetfulness this patch merges
account_system_time_scaled into account_system_time and
account_user_time_scaled into account_user_time.

Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Jeremy Fitzhardinge <jeremy@xensource.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Michael Neuling <mikey@neuling.org>
Acked-by: NPaul Mackerras <paulus@samba.org>
Signed-off-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>

Removed duplicated #include in kernel/trace/trace.c.
Signed-off-by: NHuang Weiyi <weiyi.huang@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Impact: new API to reduce stack usage

We're weaning the core code off handing cpumask's around on-stack.
This introduces arch_send_call_function_ipi_mask().
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: Implementation change to remove cpumask_t from stack.

Actually change smp_call_function_mask() to smp_call_function_many().
We avoid cpumasks on the stack in this version.

(S390 has its own version, but that's going away apparently).

We have to do some dancing to figure out if 0 or 1 other cpus are in
the mask supplied and the online mask without allocating a tmp
cpumask.  It's still fairly cheap.

We allocate the cpumask at the end of the call_function_data
structure: if allocation fails we fallback to smp_call_function_single
rather than using the baroque quiescing code (which needs a cpumask on
stack).

(Thanks to Hiroshi Shimamoto for spotting several bugs in previous versions!)
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>
Cc: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: npiggin@suse.de
Cc: axboe@kernel.dk

They're only for use in boot/cpu hotplug code anyway, and this avoids
the use of deprecated cpu_*_map.

Stephen Rothwell points out that gcc 4.2.4 (on powerpc at least)
didn't like the cast away of const anyway:

  include/linux/cpumask.h: In function 'set_cpu_possible':
  include/linux/cpumask.h:1052: warning: passing argument 2 of 'cpumask_set_cpu' discards qualifiers from pointer target type

So this kills two birds with one stone.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>

Impact: cleanup

This implements the obsolescent cpu_online_map in terms of
cpu_online_mask, rather than the other way around.  Same for the other
maps.

The documentation comments are also updated to refer to _mask rather
than _map.
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NMike Travis <travis@sgi.com>

GCC has a bug with __weak alias functions: if the functions are in
the same compilation unit as their call site, GCC can decide to
inline them - and thus rob the linker of the opportunity to override
the weak alias with the real thing.

So move all the IRQ handling related __weak symbols to kernel/irq/chip.c.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

The mm->ioctx_list is currently protected by a reader-writer lock,
so we always grab that lock on the read side for doing ioctx
lookups. As the workload is extremely reader biased, turn this into
an rcu hlist so we can make lookup_ioctx() lockless. Get rid of
the rwlock and use a spinlock for providing update side exclusion.

There's usually only 1 entry on this list, so it doesn't make sense
to look into fancier data structures.
Reviewed-by: NJeff Moyer <jmoyer@redhat.com>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

When taking recursive faults in do_exit, if the io_context is not null,
exit_io_context() is being called. But it might decrement the refcount
more than once. It is better to leave this task alone.
Signed-off-by: NNikanth Karthikesan <knikanth@suse.de>
Signed-off-by: NJens Axboe <jens.axboe@oracle.com>

Impact: fix boot crash if the kernel is built with certain GCC versions

GCC has a bug with __weak alias functions: if the functions are in
the same compilation unit as their call site, GCC can decide to
inline them - and thus rob the linker of the opportunity to override
the weak alias with the real thing.

This can lead to the boot crash reported by Kamalesh Babulal:

 ACPI: Core revision 20080926
 Setting APIC routing to flat
 BUG: unable to handle kernel NULL pointer dereference at
 0000000000000000
 IP: [<ffffffff8021f9a8>] add_pin_to_irq_cpu+0x14/0x74
 PGD 0
 Oops: 0000 [#1] SMP
 [...]

So move the arch_init_chip_data() function from handle.c to manage.c.
Reported-by: NKamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: fix hang

Suresh report his two sockets system only works with SPARSE_IRQ enable
it turns out we miss the setting desc->irq

so provide early_irq_init() even !SPARSE_IRQ to set desc->irq
Reported-by: N"Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Impact: add lockdep annotation to legacy IRQ descs

Warnings resulting out of this were not seen in practice, but it's prudent
to initialize the legacy descriptors to the lock class as well, symmetric
to how we do it with other descriptors.
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>