New cmpxchg_local (optimized for UP case) for m32r

Add __xchg_local, xchg_local (define), __cmpxchg_local_u32, __cmpxchg_local,
cmpxchg_local(macro).

cmpxchg_local and cmpxchg64_local will use the architecture specific
__cmpxchg_local_u32 for 32 bits arguments, and use the generic
__cmpxchg_local_generic for 8, 16 and 64 bits arguments.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Hirokazu Takata <takata@linux-m32r.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local, cmpxchg64 and cmpxchg64_local to ia64

Add the primitives cmpxchg_local, cmpxchg64 and cmpxchg64_local to ia64. They
use cmpxchg_acq as underlying macro, just like the already existing ia64
cmpxchg().

Changelog:

ia64 cmpxchg_local coding style fix
Quoting Keith Owens:

As a matter of coding style, I prefer

#define cmpxchg_local   cmpxchg
#define cmpxchg64_local cmpxchg64

Which makes it absolutely clear that they are the same code.  With your
patch, humans have to do a string compare of two defines to see if they
are the same.

Note cmpxchg is *not* a performance win vs interrupt disable / enable on IA64.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Christoph Lameter <clameter@sgi.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Keith Owens <kaos@ocs.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to h8300

Use the new generic cmpxchg_local (disables interrupt). Also use the generic
cmpxchg as fallback if SMP is not set.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to frv

Use the new generic cmpxchg_local (disables interrupt) for 8, 16 and 64 bits
arguments. Use the 32 bits cmpxchg available on the architecture for 32 bits
arguments.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to cris

Use the new generic cmpxchg_local (disables interrupt). Also use the generic
cmpxchg as fallback if SMP is not set.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Mikael Starvik <starvik@axis.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to blackfin, replace __cmpxchg by generic cmpxchg

Use the new generic cmpxchg_local (disables interrupt). Also use the generic
cmpxchg as fallback if SMP is not set since nobody seems to know why __cmpxchg
has been implemented in assembly in the first place thather than in plain C.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Michael Frysinger <michael.frysinger@analog.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to avr32

Use the new generic cmpxchg_local (disables interrupt) for 8, 16 and 64 bits
cmpxchg_local. Use the __cmpxchg_u32 primitive for 32 bits cmpxchg_local.

Note that cmpxchg only uses the __cmpxchg_u32 or __cmpxchg_u64 and will cause
a linker error if called with 8 or 16 bits argument.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to arm

Use the new generic cmpxchg_local (disables interrupt). Also use the generic
cmpxchg as fallback if SMP is not set.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg64 and cmpxchg64_local to x86_64

Make sure that at least cmpxchg64_local is available on all architectures to use
for unsigned long long values.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Andi Kleen <ak@muc.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg64 and cmpxchg64_local to powerpc

Make sure that at least cmpxchg64_local is available on all architectures to use
for unsigned long long values.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg64 and cmpxchg64_local to mips

Make sure that at least cmpxchg64_local is available on all architectures to use
for unsigned long long values.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg64 and cmpxchg64_local to alpha

Make sure that at least cmpxchg64_local is available on all architectures to use
for unsigned long long values.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add cmpxchg_local to asm-generic for per cpu atomic operations

Emulates the cmpxchg_local by disabling interrupts around variable modification.
This is not reentrant wrt NMIs and MCEs. It is only protected against normal
interrupts, but this is enough for architectures without such interrupt sources
or if used in a context where the data is not shared with such handlers.

It can be used as a fallback for architectures lacking a real cmpxchg
instruction.

For architectures that have a real cmpxchg but does not have NMIs or MCE,
testing which of the generic vs architecture specific cmpxchg is the fastest
should be done.

asm-generic/cmpxchg.h defines a cmpxchg that uses cmpxchg_local. It is meant to
be used as a cmpxchg fallback for architectures that do not support SMP.

* Patch series comments

Using cmpxchg_local shows a performance improvements of the fast path goes from
a 66% speedup on a Pentium 4 to a 14% speedup on AMD64.

In detail:

Tested-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Measurements on a Pentium4, 3GHz, Hyperthread.
SLUB Performance testing
========================
1. Kmalloc: Repeatedly allocate then free test

* slub HEAD, test 1
kmalloc(8) = 201 cycles         kfree = 351 cycles
kmalloc(16) = 198 cycles        kfree = 359 cycles
kmalloc(32) = 200 cycles        kfree = 381 cycles
kmalloc(64) = 224 cycles        kfree = 394 cycles
kmalloc(128) = 285 cycles       kfree = 424 cycles
kmalloc(256) = 411 cycles       kfree = 546 cycles
kmalloc(512) = 480 cycles       kfree = 619 cycles
kmalloc(1024) = 623 cycles      kfree = 750 cycles
kmalloc(2048) = 686 cycles      kfree = 811 cycles
kmalloc(4096) = 482 cycles      kfree = 538 cycles
kmalloc(8192) = 680 cycles      kfree = 734 cycles
kmalloc(16384) = 713 cycles     kfree = 843 cycles

* Slub HEAD, test 2
kmalloc(8) = 190 cycles         kfree = 351 cycles
kmalloc(16) = 195 cycles        kfree = 360 cycles
kmalloc(32) = 201 cycles        kfree = 370 cycles
kmalloc(64) = 245 cycles        kfree = 389 cycles
kmalloc(128) = 283 cycles       kfree = 413 cycles
kmalloc(256) = 409 cycles       kfree = 547 cycles
kmalloc(512) = 476 cycles       kfree = 616 cycles
kmalloc(1024) = 628 cycles      kfree = 753 cycles
kmalloc(2048) = 684 cycles      kfree = 811 cycles
kmalloc(4096) = 480 cycles      kfree = 539 cycles
kmalloc(8192) = 661 cycles      kfree = 746 cycles
kmalloc(16384) = 741 cycles     kfree = 856 cycles

* cmpxchg_local Slub test
kmalloc(8) = 83 cycles          kfree = 363 cycles
kmalloc(16) = 85 cycles         kfree = 372 cycles
kmalloc(32) = 92 cycles         kfree = 377 cycles
kmalloc(64) = 115 cycles        kfree = 397 cycles
kmalloc(128) = 179 cycles       kfree = 438 cycles
kmalloc(256) = 314 cycles       kfree = 564 cycles
kmalloc(512) = 398 cycles       kfree = 615 cycles
kmalloc(1024) = 573 cycles      kfree = 745 cycles
kmalloc(2048) = 629 cycles      kfree = 816 cycles
kmalloc(4096) = 473 cycles      kfree = 548 cycles
kmalloc(8192) = 659 cycles      kfree = 745 cycles
kmalloc(16384) = 724 cycles     kfree = 843 cycles

2. Kmalloc: alloc/free test

* slub HEAD, test 1
kmalloc(8)/kfree = 322 cycles
kmalloc(16)/kfree = 318 cycles
kmalloc(32)/kfree = 318 cycles
kmalloc(64)/kfree = 325 cycles
kmalloc(128)/kfree = 318 cycles
kmalloc(256)/kfree = 328 cycles
kmalloc(512)/kfree = 328 cycles
kmalloc(1024)/kfree = 328 cycles
kmalloc(2048)/kfree = 328 cycles
kmalloc(4096)/kfree = 678 cycles
kmalloc(8192)/kfree = 1013 cycles
kmalloc(16384)/kfree = 1157 cycles

* Slub HEAD, test 2
kmalloc(8)/kfree = 323 cycles
kmalloc(16)/kfree = 318 cycles
kmalloc(32)/kfree = 318 cycles
kmalloc(64)/kfree = 318 cycles
kmalloc(128)/kfree = 318 cycles
kmalloc(256)/kfree = 328 cycles
kmalloc(512)/kfree = 328 cycles
kmalloc(1024)/kfree = 328 cycles
kmalloc(2048)/kfree = 328 cycles
kmalloc(4096)/kfree = 648 cycles
kmalloc(8192)/kfree = 1009 cycles
kmalloc(16384)/kfree = 1105 cycles

* cmpxchg_local Slub test
kmalloc(8)/kfree = 112 cycles
kmalloc(16)/kfree = 103 cycles
kmalloc(32)/kfree = 103 cycles
kmalloc(64)/kfree = 103 cycles
kmalloc(128)/kfree = 112 cycles
kmalloc(256)/kfree = 111 cycles
kmalloc(512)/kfree = 111 cycles
kmalloc(1024)/kfree = 111 cycles
kmalloc(2048)/kfree = 121 cycles
kmalloc(4096)/kfree = 650 cycles
kmalloc(8192)/kfree = 1042 cycles
kmalloc(16384)/kfree = 1149 cycles

Tested-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Measurements on a AMD64 2.0 GHz dual-core

In this test, we seem to remove 10 cycles from the kmalloc fast path.
On small allocations, it gives a 14% performance increase. kfree fast
path also seems to have a 10 cycles improvement.

1. Kmalloc: Repeatedly allocate then free test

* cmpxchg_local slub
kmalloc(8) = 63 cycles      kfree = 126 cycles
kmalloc(16) = 66 cycles     kfree = 129 cycles
kmalloc(32) = 76 cycles     kfree = 138 cycles
kmalloc(64) = 100 cycles    kfree = 288 cycles
kmalloc(128) = 128 cycles   kfree = 309 cycles
kmalloc(256) = 170 cycles   kfree = 315 cycles
kmalloc(512) = 221 cycles   kfree = 357 cycles
kmalloc(1024) = 324 cycles  kfree = 393 cycles
kmalloc(2048) = 354 cycles  kfree = 440 cycles
kmalloc(4096) = 394 cycles  kfree = 330 cycles
kmalloc(8192) = 523 cycles  kfree = 481 cycles
kmalloc(16384) = 643 cycles kfree = 649 cycles

* Base
kmalloc(8) = 74 cycles      kfree = 113 cycles
kmalloc(16) = 76 cycles     kfree = 116 cycles
kmalloc(32) = 85 cycles     kfree = 133 cycles
kmalloc(64) = 111 cycles    kfree = 279 cycles
kmalloc(128) = 138 cycles   kfree = 294 cycles
kmalloc(256) = 181 cycles   kfree = 304 cycles
kmalloc(512) = 237 cycles   kfree = 327 cycles
kmalloc(1024) = 340 cycles  kfree = 379 cycles
kmalloc(2048) = 378 cycles  kfree = 433 cycles
kmalloc(4096) = 399 cycles  kfree = 329 cycles
kmalloc(8192) = 528 cycles  kfree = 624 cycles
kmalloc(16384) = 651 cycles kfree = 737 cycles

2. Kmalloc: alloc/free test

* cmpxchg_local slub
kmalloc(8)/kfree = 96 cycles
kmalloc(16)/kfree = 97 cycles
kmalloc(32)/kfree = 97 cycles
kmalloc(64)/kfree = 97 cycles
kmalloc(128)/kfree = 97 cycles
kmalloc(256)/kfree = 105 cycles
kmalloc(512)/kfree = 108 cycles
kmalloc(1024)/kfree = 105 cycles
kmalloc(2048)/kfree = 107 cycles
kmalloc(4096)/kfree = 390 cycles
kmalloc(8192)/kfree = 626 cycles
kmalloc(16384)/kfree = 662 cycles

* Base
kmalloc(8)/kfree = 116 cycles
kmalloc(16)/kfree = 116 cycles
kmalloc(32)/kfree = 116 cycles
kmalloc(64)/kfree = 116 cycles
kmalloc(128)/kfree = 116 cycles
kmalloc(256)/kfree = 126 cycles
kmalloc(512)/kfree = 126 cycles
kmalloc(1024)/kfree = 126 cycles
kmalloc(2048)/kfree = 126 cycles
kmalloc(4096)/kfree = 384 cycles
kmalloc(8192)/kfree = 749 cycles
kmalloc(16384)/kfree = 786 cycles

Tested-by: Christoph Lameter <clameter@sgi.com>
I can confirm Mathieus' measurement now:

Athlon64:

regular NUMA/discontig

1. Kmalloc: Repeatedly allocate then free test
10000 times kmalloc(8) -> 79 cycles kfree -> 92 cycles
10000 times kmalloc(16) -> 79 cycles kfree -> 93 cycles
10000 times kmalloc(32) -> 88 cycles kfree -> 95 cycles
10000 times kmalloc(64) -> 124 cycles kfree -> 132 cycles
10000 times kmalloc(128) -> 157 cycles kfree -> 247 cycles
10000 times kmalloc(256) -> 200 cycles kfree -> 257 cycles
10000 times kmalloc(512) -> 250 cycles kfree -> 277 cycles
10000 times kmalloc(1024) -> 337 cycles kfree -> 314 cycles
10000 times kmalloc(2048) -> 365 cycles kfree -> 330 cycles
10000 times kmalloc(4096) -> 352 cycles kfree -> 240 cycles
10000 times kmalloc(8192) -> 456 cycles kfree -> 340 cycles
10000 times kmalloc(16384) -> 646 cycles kfree -> 471 cycles
2. Kmalloc: alloc/free test
10000 times kmalloc(8)/kfree -> 124 cycles
10000 times kmalloc(16)/kfree -> 124 cycles
10000 times kmalloc(32)/kfree -> 124 cycles
10000 times kmalloc(64)/kfree -> 124 cycles
10000 times kmalloc(128)/kfree -> 124 cycles
10000 times kmalloc(256)/kfree -> 132 cycles
10000 times kmalloc(512)/kfree -> 132 cycles
10000 times kmalloc(1024)/kfree -> 132 cycles
10000 times kmalloc(2048)/kfree -> 132 cycles
10000 times kmalloc(4096)/kfree -> 319 cycles
10000 times kmalloc(8192)/kfree -> 486 cycles
10000 times kmalloc(16384)/kfree -> 539 cycles

cmpxchg_local NUMA/discontig

1. Kmalloc: Repeatedly allocate then free test
10000 times kmalloc(8) -> 55 cycles kfree -> 90 cycles
10000 times kmalloc(16) -> 55 cycles kfree -> 92 cycles
10000 times kmalloc(32) -> 70 cycles kfree -> 91 cycles
10000 times kmalloc(64) -> 100 cycles kfree -> 141 cycles
10000 times kmalloc(128) -> 128 cycles kfree -> 233 cycles
10000 times kmalloc(256) -> 172 cycles kfree -> 251 cycles
10000 times kmalloc(512) -> 225 cycles kfree -> 275 cycles
10000 times kmalloc(1024) -> 325 cycles kfree -> 311 cycles
10000 times kmalloc(2048) -> 346 cycles kfree -> 330 cycles
10000 times kmalloc(4096) -> 351 cycles kfree -> 238 cycles
10000 times kmalloc(8192) -> 450 cycles kfree -> 342 cycles
10000 times kmalloc(16384) -> 630 cycles kfree -> 546 cycles
2. Kmalloc: alloc/free test
10000 times kmalloc(8)/kfree -> 81 cycles
10000 times kmalloc(16)/kfree -> 81 cycles
10000 times kmalloc(32)/kfree -> 81 cycles
10000 times kmalloc(64)/kfree -> 81 cycles
10000 times kmalloc(128)/kfree -> 81 cycles
10000 times kmalloc(256)/kfree -> 91 cycles
10000 times kmalloc(512)/kfree -> 90 cycles
10000 times kmalloc(1024)/kfree -> 91 cycles
10000 times kmalloc(2048)/kfree -> 90 cycles
10000 times kmalloc(4096)/kfree -> 318 cycles
10000 times kmalloc(8192)/kfree -> 483 cycles
10000 times kmalloc(16384)/kfree -> 536 cycles

Changelog:
- Ran though checkpatch.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Sanitize the type of struct user.u_ar0

struct user.u_ar0 is defined to contain a pointer offset on all
architectures in which it is defined (all architectures which define an
a.out format except SPARC.) However, it has a pointer type in the headers,
which is pointless -- <asm/user.h> is not exported to userspace, and it
just makes the code messy.

Redefine the field as "unsigned long" (which is the same size as a pointer
on all Linux architectures) and change the setting code to user offsetof()
instead of hand-coded arithmetic.

Cc: Linux Arch Mailing List <linux-arch@vger.kernel.org>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Lennert Buytenhek <kernel@wantstofly.org>
Cc: Håvard Skinnemoen <hskinnemoen@atmel.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Ralf Baechle <ralf@linux-mips.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>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Unexport asm/page.h

Do not export asm/page.h during make headers_install.  This removes PAGE_SIZE
from userspace headers.

Signed-off-by: Kirill A. Shutemov <k.shutemov@gmail.com>
Reviewed-by: David Woodhouse <dwmw2@infradead.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Unexport asm/elf.h

Do not export asm/elf.h during make headers_install.

Signed-off-by: Kirill A. Shutemov <k.shutemov@gmail.com>
Reviewed-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Cleanup asm/{elf,page,user}.h: #ifdef __KERNEL__ is no longer needed

asm/elf.h, asm/page.h and asm/user.h don't export to userspace now, so we can
drop #ifdef __KERNEL__ for them.

[k.shutemov@gmail.com: remove #ifdef __KERNEL_]
Signed-off-by: Kirill A. Shutemov <k.shutemov@gmail.com>
Reviewed-by: David Woodhouse <dwmw2@infradead.org>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Kirill A. Shutemov <k.shutemov@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Unexport asm/user.h and linux/user.h

Do not export asm/user.h and linux/user.h during make headers_install.

Signed-off-by: Kirill A. Shutemov <k.shutemov@gmail.com>
Reviewed-by: David Woodhouse <dwmw2@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Acked-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: remove iget() and the read_inode() super op as being obsolete

Remove the old iget() call and the read_inode() superblock operation it uses
as these are really obsolete, and the use of read_inode() does not produce
proper error handling (no distinction between ENOMEM and EIO when marking an
inode bad).

Furthermore, this removes the temptation to use iget() to find an inode by
number in a filesystem from code outside that filesystem.

iget_locked() should be used instead.  A new function is added in an earlier
patch (iget_failed) that is to be called to mark an inode as bad, unlock it
and release it should the get routine fail.  Mark iget() and read_inode() as
being obsolete and remove references to them from the documentation.

Typically a filesystem will be modified such that the read_inode function
becomes an internal iget function, for example the following:

void thingyfs_read_inode(struct inode *inode)
{
...
}

would be changed into something like:

struct inode *thingyfs_iget(struct super_block *sp, unsigned long ino)
{
struct inode *inode;
int ret;

inode = iget_locked(sb, ino);
if (!inode)
return ERR_PTR(-ENOMEM);
if (!(inode->i_state & I_NEW))
return inode;

...
unlock_new_inode(inode);
return inode;
error:
iget_failed(inode);
return ERR_PTR(ret);
}

and then thingyfs_iget() would be called rather than iget(), for example:

ret = -EINVAL;
inode = iget(sb, ino);
if (!inode || is_bad_inode(inode))
goto error;

becomes:

inode = thingyfs_iget(sb, ino);
if (IS_ERR(inode)) {
ret = PTR_ERR(inode);
goto error;
}

Note that is_bad_inode() does not need to be called.  The error returned by
thingyfs_iget() should render it unnecessary.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop HPPFS from using iget() and read_inode()

Stop the HPPFS filesystem from using iget() and read_inode().  Provide an
hppfs_iget(), and call that instead of iget().  hppfs_iget() then uses
iget_locked() directly and returns a proper error code instead of an inode in
the event of an error.

hppfs_fill_sb_common() returns any error incurred when getting the root inode
instead of EINVAL.

Note that the contents of hppfs_kern.c need to be examined:

 (*) The HPPFS inode retains a pointer to the proc dentry it is shadowing, but
     whilst it does appear to retain a reference to it, it doesn't appear to
     destroy the reference if the inode goes away.

 (*) hppfs_iget() should perhaps subsume init_inode() and hppfs_read_inode().

 (*) It would appear that all hppfs inodes are the same inode because iget()
     was being called with inode number 0, which forms the lookup key.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop HOSTFS from using iget() and read_inode()

Stop the HOSTFS filesystem from using iget() and read_inode().  Provide
hostfs_iget(), and call that instead of iget().  hostfs_iget() then uses
iget_locked() directly and returns a proper error code instead of an inode in
the event of an error.

hostfs_fill_sb_common() returns any error incurred when getting the root inode
instead of EINVAL.

Note that the contents of hostfs_kern.c need to be examined:

 (*) hostfs_iget() should perhaps subsume init_inode() and hostfs_read_inode().

 (*) It would appear that all hostfs inodes are the same inode because iget()
     was being called with inode number 0 - which forms the lookup key.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Jeff Dike <jdike@addtoit.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop OPENPROMFS from using iget() and read_inode()

Stop the OPENPROMFS filesystem from using iget() and read_inode().  Replace
openpromfs_read_inode() with openpromfs_iget(), and call that instead of
iget().  openpromfs_iget() then uses iget_locked() directly and returns a
proper error code instead of an inode in the event of an error.

openpromfs_fill_super() returns any error incurred when getting the root inode
instead of ENOMEM (not that it currently incurs any other error).

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop UFS from using iget() and read_inode()

Stop the UFS filesystem from using iget() and read_inode().  Replace
ufs_read_inode() with ufs_iget(), and call that instead of iget().  ufs_iget()
then uses iget_locked() directly and returns a proper error code instead of an
inode in the event of an error.

ufs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop the SYSV filesystem from using iget() and read_inode()

Stop the SYSV filesystem from using iget() and read_inode().  Replace
sysv_read_inode() with sysv_iget(), and call that instead of iget().
sysv_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop ROMFS from using iget() and read_inode()

Stop the ROMFS filesystem from using iget() and read_inode().  Replace
romfs_read_inode() with romfs_iget(), and call that instead of iget().
romfs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

romfs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop QNX4 from using iget() and read_inode()

Stop the QNX4 filesystem from using iget() and read_inode().  Replace
qnx4_read_inode() with qnx4_iget(), and call that instead of iget().
qnx4_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

qnx4_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Anders Larsen <al@alarsen.net>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop PROCFS from using iget() and read_inode()

Stop the PROCFS filesystem from using iget() and read_inode().  Merge
procfs_read_inode() into procfs_get_inode(), and have that call iget_locked()
instead of iget().

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop the MINIX filesystem from using iget() and read_inode()

Stop the MINIX filesystem from using iget() and read_inode().  Replace
minix_read_inode() with minix_iget(), and call that instead of iget().
minix_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

minix_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop JFS from using iget() and read_inode()

Stop the JFS filesystem from using iget() and read_inode().  Replace
jfs_read_inode() with jfs_iget(), and call that instead of iget().  jfs_iget()
then uses iget_locked() directly and returns a proper error code instead of an
inode in the event of an error.

jfs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop JFFS2 from using iget() and read_inode()

Stop the JFFS2 filesystem from using iget() and read_inode().  Replace
jffs2_read_inode() with jffs2_iget(), and call that instead of iget().
jffs2_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

jffs2_do_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop ISOFS from using read_inode()

Stop the ISOFS filesystem from using read_inode().  Make isofs_read_inode()
return an error code, and make isofs_iget() pass it on.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Jan Kara <jack@ucw.cz>
Acked-by: Christoph Hellwig <hch@lst.de>
Cc: "Dave Young" <hidave.darkstar@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop HFSPLUS from using iget() and read_inode()

Stop the HFSPLUS filesystem from using iget() and read_inode().  Replace
hfsplus_read_inode() with hfsplus_iget(), and call that instead of iget().
hfsplus_iget() then uses iget_locked() directly and returns a proper error
code instead of an inode in the event of an error.

hfsplus_fill_super() returns any error incurred when getting the root inode.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop FUSE from using iget() and read_inode()

Stop the FUSE filesystem from using read_inode(), which it doesn't use anyway.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop FreeVXFS from using iget() and read_inode()

Stop the FreeVXFS filesystem from using iget() and read_inode().  Replace
vxfs_read_inode() with vxfs_iget(), and call that instead of iget().
vxfs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

vxfs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop FAT from using iget() and read_inode()

Stop the FAT filesystem from using iget() and read_inode().  Replace the call
to iget() with a call to ilookup().

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop EXT4 from using iget() and read_inode()

Stop the EXT4 filesystem from using iget() and read_inode().  Replace
ext4_read_inode() with ext4_iget(), and call that instead of iget().
ext4_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

ext4_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop EXT3 from using iget() and read_inode()

Stop the EXT3 filesystem from using iget() and read_inode().  Replace
ext3_read_inode() with ext3_iget(), and call that instead of iget().
ext3_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

ext3_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop EXT2 from using iget() and read_inode()

Stop the EXT2 filesystem from using iget() and read_inode().  Replace
ext2_read_inode() with ext2_iget(), and call that instead of iget().
ext2_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

ext2_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: <linux-ext4@vger.kernel.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop EFS from using iget() and read_inode()

Stop the EFS filesystem from using iget() and read_inode().  Replace
efs_read_inode() with efs_iget(), and call that instead of iget().  efs_iget()
then uses iget_locked() directly and returns a proper error code instead of an
inode in the event of an error.

efs_fill_super() returns any error incurred when getting the root inode
instead of EACCES.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop CIFS from using iget() and read_inode()

Stop the CIFS filesystem from using iget() and read_inode().  Replace
cifs_read_inode() with cifs_iget(), and call that instead of iget().
cifs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

cifs_read_super() now returns any error incurred when getting the root inode
instead of ENOMEM.

cifs_iget() needs examining.  The comment "can not call macro FreeXid here
since in a void func" is no longer true.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Steven French <sfrench@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop BFS from using iget() and read_inode()

Stop the BFS filesystem from using iget() and read_inode().  Replace
bfs_read_inode() with bfs_iget(), and call that instead of iget().  bfs_iget()
then uses iget_locked() directly and returns a proper error code instead of an
inode in the event of an error.

bfs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[kamalesh@linux.vnet.ibm.com: build fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop BEFS from using iget() and read_inode()

Stop the BEFS filesystem from using iget() and read_inode().  Replace
befs_read_inode() with befs_iget(), and call that instead of iget().
befs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

befs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Will Dyson <will_dyson@pobox.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop autofs from using iget() and read_inode()

Stop the autofs filesystem from using iget() and read_inode().  Replace
autofs_read_inode() with autofs_iget(), and call that instead of iget().
autofs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Ian Kent <raven@themaw.net>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: stop AFFS from using iget() and read_inode()

Stop the AFFS filesystem from using iget() and read_inode().  Replace
affs_read_inode() with affs_iget(), and call that instead of iget().
affs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

affs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Roman Zippel <zippel@linux-m68k.org>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: use iget_failed() in GFS2

Use iget_failed() in GFS2 to kill a failed inode.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: use iget_failed() in AFS

Use iget_failed() in AFS to kill a failed inode.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

iget: introduce a function to register iget failure

Introduce a function to register failure in an inode construction path.  This
includes marking the inode under construction as bad, unlocking it and
releasing it.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Convert ERR_PTR(PTR_ERR(p)) instances to ERR_CAST(p)

Convert instances of ERR_PTR(PTR_ERR(p)) to ERR_CAST(p) using:

perl -spi -e 's/ERR_PTR[(]PTR_ERR[(](.*)[)][)]/ERR_CAST(\1)/' `grep -rl 'ERR_PTR[(]*PTR_ERR' fs crypto net security`

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Add an ERR_CAST() function to complement ERR_PTR and co.

Add an ERR_CAST() function to complement ERR_PTR and co.  for the purposes
of casting an error entyped as one pointer type to an error of another
pointer type whilst making it explicit as to what is going on.

This provides a replacement for the ERR_PTR(PTR_ERR(p)) construct.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MBCS: convert dmareadlock to mutex

MBCS: Convert the semaphore dmareadlock to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MBCS: convert dmawritelock to mutex

MBCS: Convert the semaphore dmawritelock to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MBCS: convert algolock to mutex

MBCS: Convert the semaphore algolock to the mutex API

Signed-off-by: Matthias Kaehlcke <matthias.kaehlcke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vmcoreinfo: fix the configuration dependencies

This patch fixes the configuration dependencies in the vmcoreinfo data.

i386's "node_data" is defined in arch/x86/mm/discontig_32.c,
and x86_64's one is defined in arch/x86/mm/numa_64.c.
They depend on CONFIG_NUMA:
  arch/x86/mm/Makefile_32:7
    obj-$(CONFIG_NUMA) += discontig_32.o
  arch/x86/mm/Makefile_64:7
    obj-$(CONFIG_NUMA) += numa_64.o

ia64's "pgdat_list" is defined in arch/ia64/mm/discontig.c,
and it depends on CONFIG_DISCONTIGMEM and CONFIG_SPARSEMEM:
  arch/ia64/mm/Makefile:9-10
    obj-$(CONFIG_DISCONTIGMEM) += discontig.o
    obj-$(CONFIG_SPARSEMEM)    += discontig.o

ia64's "node_memblk" is defined in arch/ia64/mm/numa.c,
and it depends on CONFIG_NUMA:
  arch/ia64/mm/Makefile:8
    obj-$(CONFIG_NUMA)         += numa.o

Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Simon Horman <horms@verge.net.au>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vmcoreinfo: add "VMCOREINFO_" to all the call for vmcoreinfo_append_str()

For readability, all the calls to vmcoreinfo_append_str() are changed to macros
having a prefix "VMCOREINFO_".

This discussion is the following:
http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0584.html

Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Simon Horman <horms@verge.net.au>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vmcoreinfo: use the existing offsetof() for VMCOREINFO_OFFSET()

It is better that the existing offsetof() is used for VMCOREINFO_OFFSET().

This discussion is the following:
http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0584.html

Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: Simon Horman <horms@verge.net.au>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

vmcoreinfo: rename vmcoreinfo's macros returning the size

This patchset is for the vmcoreinfo data.

The vmcoreinfo data has the minimum debugging information only for dump
filtering.  makedumpfile (dump filtering command) gets it to distinguish
unnecessary pages, and makedumpfile creates a small dumpfile.

This patch:

VMCOREINFO_SIZE() should be renamed VMCOREINFO_STRUCT_SIZE() since it's always
returning the size of the struct with a given name. This change would allow
VMCOREINFO_TYPEDEF_SIZE() to simply become VMCOREINFO_SIZE() since it need not
be used exclusively for typedefs.

This discussion is the following:
http://www.ussg.iu.edu/hypermail/linux/kernel/0709.3/0582.html

Signed-off-by: Ken'ichi Ohmichi <oomichi@mxs.nes.nec.co.jp>
Acked-by: David Rientjes <rientjes@google.com>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use BOOTMEM_EXCLUSIVE for kdump

Use the BOOTMEM_EXCLUSIVE, introduced in the previous patch, to avoid
conflicts while reserving the memory for the kdump capture kernel
(crashkernel=).

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Introduce flags for reserve_bootmem()

This patchset adds a flags variable to reserve_bootmem() and uses the
BOOTMEM_EXCLUSIVE flag in crashkernel reservation code to detect collisions
between crashkernel area and already used memory.

This patch:

Change the reserve_bootmem() function to accept a new flag BOOTMEM_EXCLUSIVE.
If that flag is set, the function returns with -EBUSY if the memory already
has been reserved in the past.  This is to avoid conflicts.

Because that code runs before SMP initialisation, there's no race condition
inside reserve_bootmem_core().

[akpm@linux-foundation.org: coding-style fixes]
[akpm@linux-foundation.org: fix powerpc build]
Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: <linux-arch@vger.kernel.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Vivek Goyal <vgoyal@in.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs menu: small reorg

- move minixfs and ROMfs to the Miscellaneous filesystems menu
- move DNOTIFY config symbol so that it is adjacent to INOTIFY
  instead of being split by the QUOTA config options
- add some 'endif' annotations
- remove some whitespace (extra blank lines)

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz.c: Resource management

This is a set of changes to implement proper resource management in the
driver, including iomem space reservation and operating on physical
addresses ioremap()ped appropriately using accessory functions rather than
unportable direct assignments.

Some adjustments to code are made to reflect the architecture of the
interface, which is a centrally controlled multiport (or, as referred to
from DEC documentation, a serial line multiplexer, going up to 8 lines
originally) rather than a bundle of separate ports.

Types are changed, where applicable, to specify the width of hardware
registers explicitly.  The interrupt handler is now managed in the
->startup() and ->shutdown() calls for consistency with other drivers and
also in preparation to handle the handover from the initial firmware-based
console gracefully.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz.c: Use a helper to cast from "struct uart_port *"

Replace all casts from "struct uart_port *" to "struct dz_port *" with a
construct based on container_of().  This makes the conversion work
irrespective of where the former struct is located within the latter.

By popular request I have implemented it as an inline function rather than
a macro this time.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: clean up and improve the setup of termios settings

A set of changes to the way termios settings are propagated to the serial
port hardware.  The DZ11 only supports a selection of fixed baud settings,
so some requests may not be fulfilled.  Keep the old setting in such a case
and failing that resort to 9600bps.  Also add a missing update of the
transmit timeout.  And remove the explicit encoding of the line selected
from writes to the Line Parameters Register as it has been preencoded by
the ->set_termios() call already.  Finally, remove a duplicate macro for
the Receiver Enable bit.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

MAINTAINERS: add self for the dz serial driver

Now that I have got the necessary piece of hardware (thanks, Thiemo!), I may
well offer myself as the maintainer for the dz serial driver.  I hope nobody
objects.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: handle special conditions on reception correctly

Handle the read and ignore status masks correctly.  Handle the BREAK condition
as expected: a framing error with a null character is a BREAK, any other
framing error is a framing error indeed.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: fix locking issues

The ->start_tx(), ->stop_tx() and ->stop_rx() backends are called with the
port's lock already taken.  Remove locking from within them and wrap around
calls as necessary.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: rename the serial console structure

Rename the serial console structure so that `modpost' does not complain about
a reference to an "init" section -- "_console" is magic.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: update kconfig description

Reformat the Kconfig entries and update descriptions for accuracy.  Select the
driver by default for configurations of interest.  For the curious: 32BIT
means only 32-bit DECstations support the device, not that the driver is not
64-bit clean; I have not checked that either though.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: add and reorder inclusions, remove unneeded ones

Sort the header inclusions, add a few that are needed but pulled indirectly
only and remove ones that are not really used.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: don't panic() when request_irq() fails

Well, panic() is a little bit undue if request_irq() fails; there is probably
no need to justify it any further.  Handle the case gracefully, by
unregistering the driver.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz: always check if it is safe to console_putchar()

Polled transmission is tricky enough with the DZ11 design.  While "loop" is
set to a high value, conceptually you are not allowed to transmit without
checking whether the device offers the right transmission line (yes, it is the
device that selects the line -- the driver has no control over it other than
disabling the transmitter offered if it is the wrong one), so the loop has to
be run at least once.

Well, the '1977 or PDP11 view of how serial lines should be handled...  Except
that the serial interface used to be quite an impressive board back then
rather than chip.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

dz.h: remove useless unused module junk

Remove unused module function prototypes that would not even build if enabled.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/edac/i3000: document type promotion

By popular request, add a comment documenting the implicit type promotion
here.

Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/edac: i3000: missing init code

There is a missing sequence of initialization code during startup.

Signed-off-by: Hitoshi Mitake <h.mitake@gmail.com>
Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Signed-off-by: Doug Thompson <dougthompson@xmisson.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/edac: mpc85xx: add static scope

Made a previous global variable, static in scope

Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/edac: i3000: 64bit build

Modified to run on x86_64 as well as x86

i3000_edac builds (and runs) fine on x86_64.

Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/edac: pci: broken parity regression

Using the EDAC code in kernel.org kernel version 2.6.23.8 I am seeing the
following problem:

    In the kernel there is a pci device attribute located in sysfs that is
    checked by the EDAC PCI scanning code. If that attribute is set,
    PCI parity/error scannining is skipped for that device. The attribute
    is:

            broken_parity_status

    as is located in /sys/devices/pci<XXX>/0000:XX:YY.Z directorys for
    PCI devices.

I don't think this check was actually implemented.  I have a misbehaved card
that reports a parity error every 1000 ms:

Nov 25 07:28:43 beta kernel: EDAC PCI: Master Data Parity Error on 0000:05:01.0
Nov 25 07:28:44 beta kernel: EDAC PCI: Master Data Parity Error on 0000:05:01.0
Nov 25 07:28:45 beta kernel: EDAC PCI: Master Data Parity Error on 0000:05:01.0

Setting that card's broken_parity_status bit did not mask the error:

echo "1" > /sys/bus/pci/devices/0000:05:01.0/broken_parity_status

I looked through the EDAC code and did not readily see any reference to
broken_parity_status at all (which makes sense based on the behavior I am
seeing).  I applied the following patch as a proof-of-concept and now EDAC's
PCI parity error reporting behaves as documented:

bryan

Good regression find, bryan. It used to work. sigh.
I added more logic to your patch, for more coverage of the error.

Doug T

Signed-off-by: Bryan Boatright <b1@omega71.com>
Signed-off-by: Doug Thompson <dougthompson@xmisson.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: add marvell mv64x60 driver

Marvell mv64x60 SoC support for EDAC.  Used on PPC and MIPS platforms.
Development and testing done on PPC Motorola prpmc2800 ATCA board.

[akpm@linux-foundation.org: make mv64x60_ctl_name static]
Signed-off-by: Dave Jiang <djiang@mvista.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Douglas Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: add freescale mpc85xx driver

EDAC chip driver support for Freescale MPC85xx platforms. PPC based.

Signed-off-by: Dave Jiang <djiang@mvista.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: i3000 replace macros with functions

Replace function-like macros with functions.

Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: i3000 code tidying

Style cleanup, mostly just 80-column fixes.

Signed-off-by: Jason Uhlenkott <juhlenko@akamai.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: add Cell MC driver

Adds driver for the Cell memory controller when used without a Hypervisor such
as on the IBM Cell blades.  There might still be some improvements to do to
this such as finding if it's possible to properly obtain more details about
the address of the error but it's good enough already to report CE counts
which is our main priority at the moment.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: add Cell XDR memory types

Add the definitions for the Rambus XDR memory type used by the Cell processor.
It's a pre-requisite for the followup Cell EDAC patch.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: use round_jiffies_relative

When rounding a relative timeout we need to use round_jiffies_relative().

Signed-off-by: Anton Blanchard <anton@samba.org>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers-edac: turn on edac device error logging

ENABLE the 'logging' of CE and UE events for the EDAC_DEVICE class of error
harvester in EDAC

Cc: Alan Cox <alan@lxorguk.ukuu.org.uk
Signed-off-by: Doug Thompson <dougthompson@xmission.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

ASIC3 driver

This is a patch for the Compaq ASIC3 multi function chip, found in many
PDAs (iPAQs, HTCs...).

It is a simplified version of Paul Sokolovsky's first proposal [1].  With
this code, it is basically a GPIO and IRQ expander.  My plan is to add more
features once this patch gets reviewed and accepted.

[1] http://lkml.org/lkml/2007/5/1/46

Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
Cc: Paul Sokolovsky <pmiscml@gmail.com>
Cc: Ben Dooks <ben@trinity.fluff.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

cpusets: update_cpumask documentation fix

Update cpuset documentation to match the October 2007 "Fix cpusets
update_cpumask" changes that now apply changes to a cpusets 'cpus' allowed
mask immediately to the cpus_allowed of the tasks in that cpuset.

Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Cliff Wickman <cpw@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Handle pid namespaces in cgroups code

There's one place that works with task pids - its the "tasks" file in cgroups.
 The read/write handlers assume, that the pid values go to/come from the user
space and thus it is a virtual pid, i.e.  the pid as it is seen from inside a
namespace.

Tune the code accordingly.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hotplug cpu move tasks in empty cpusets - refinements

- Narrow the scope of callback_mutex in scan_for_empty_cpusets().

- Avoid rewriting the cpus, mems of cpusets except when it is likely that
  we'll be changing them.

- Have remove_tasks_in_empty_cpuset() also check for empty mems.

Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Cliff Wickman <cpw@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hotplug cpu: move tasks in empty cpusets to parent various other fixes

Various minor formatting and comment tweaks to Cliff Wickman's
[PATCH_3_of_3]_cpusets__update_cpumask_revision.patch

I had had "iff", meaning "if and only if" in a comment.  However, except for
ancient mathematicians, the abbreviation "iff" was a tad too cryptic.  Cliff
changed it to "if", presumably figuring that the "iff" was a typo.  However,
it was the "only if" half of the conjunction that was most interesting.
Reword to emphasis the "only if" aspect.

The locking comment for remove_tasks_in_empty_cpuset() was wrong; it said
callback_mutex had to be held on entry.  The opposite is true.

Several mentions of attach_task() in comments needed to be
changed to cgroup_attach_task().

A comment about notify_on_release was no longer relevant,
as the line of code it had commented, namely:
set_bit(CS_RELEASED_RESOURCE, &parent->flags);
is no longer present in that place in the cpuset.c code.

Similarly a comment about notify_on_release before the
scan_for_empty_cpusets() routine was no longer relevant.

Removed extra parentheses and unnecessary return statement.

Renamed attach_task() to cpuset_attach() in various comments.

Removed comment about not needing memory migration, as it seems the migration
is done anyway, via the cpuset_attach() callback from cgroup_attach_task().

Signed-off-by: Paul Jackson <pj@sgi.com>
Acked-by: Cliff Wickman <cpw@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Paul Menage <menage@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

cgroups: update comments in cpuset.c

Some of the comments in kernel/cpuset.c were stale following the
transition to control groups; this patch updates them to more closely
match reality.

Signed-off-by: Paul Menage <menage@google.com>
Acked-by: Paul Jackson <pj@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

cpusets: update_cpumask revision

Use the new function cgroup_scan_tasks() to step through all tasks in a
cpuset.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

hotplug cpu: move tasks in empty cpusets to parent

This patch corrects a situation that occurs when one disables all the cpus in
a cpuset.

Currently, the disabled (cpu-less) cpuset inherits the cpus of its parent,
which is incorrect because it may then overlap its cpu-exclusive sibling.

Tasks of an empty cpuset should be moved to the cpuset which is the parent of
their current cpuset.  Or if the parent cpuset has no cpus, to its parent,
etc.

And the empty cpuset should be released (if it is flagged notify_on_release).

Depends on the cgroup_scan_tasks() function (proposed by David Rientjes) to
iterate through all tasks in the cpu-less cpuset.  We are deliberately
avoiding a walk of the tasklist.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

cgroups: mechanism to process each task in a cgroup

Provide cgroup_scan_tasks(), which iterates through every task in a cgroup,
calling a test function and a process function for each.  And call the process
function without holding the css_set_lock lock.

The idea is David Rientjes', predicting that such a function will make it much
easier in the future to extend things that require access to each task in a
cgroup without holding the lock,

[akpm@linux-foundation.org: cleanup]
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Cc: Paul Menage <menage@google.com>
Cc: Paul Jackson <pj@sgi.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

update Documentation/controller/memory.txt

Documentation updates for memory controller.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Memory controller remove control_type feature

Based on the discussion at http://lkml.org/lkml/2007/12/20/383, it was felt
that control_type might not be a good thing to implement right away.  We
can add this flexibility at a later point when required.

Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

per-zone and reclaim enhancements for memory controller: per-zone-lock for cgroup

Now, lru is per-zone.

Then, lru_lock can be (should be) per-zone, too.
This patch implementes per-zone lru lock.

lru_lock is placed into mem_cgroup_per_zone struct.

lock can be accessed by
   mz = mem_cgroup_zoneinfo(mem_cgroup, node, zone);
   &mz->lru_lock

   or
   mz = page_cgroup_zoneinfo(page_cgroup);
   &mz->lru_lock

Signed-off-by: KAMEZAWA hiroyuki <kmaezawa.hiroyu@jp.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

per-zone and reclaim enhancements for memory controller: per zone lru for cgroup

This patch implements per-zone lru for memory cgroup.
This patch makes use of mem_cgroup_per_zone struct for per zone lru.

LRU can be accessed by

   mz = mem_cgroup_zoneinfo(mem_cgroup, node, zone);
   &mz->active_list
   &mz->inactive_list

   or
   mz = page_cgroup_zoneinfo(page_cgroup);
   &mz->active_list
   &mz->inactive_list

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

per-zone and reclaim enhancements for memory controller: modifies vmscan.c for isolate globa/cgroup lru activity

When using memory controller, there are 2 levels of memory reclaim.
 1. zone memory reclaim because of system/zone memory shortage.
 2. memory cgroup memory reclaim because of hitting limit.

These two can be distinguished by sc->mem_cgroup parameter.
(scan_global_lru() macro)

This patch tries to make memory cgroup reclaim routine avoid affecting
system/zone memory reclaim. This patch inserts if (scan_global_lru()) and
hook to memory_cgroup reclaim support functions.

This patch can be a help for isolating system lru activity and group lru
activity and shows what additional functions are necessary.

 * mem_cgroup_calc_mapped_ratio() ... calculate mapped ratio for cgroup.
 * mem_cgroup_reclaim_imbalance() ... calculate active/inactive balance in
                                        cgroup.
 * mem_cgroup_calc_reclaim_active() ... calculate the number of active pages to
                                be scanned in this priority in mem_cgroup.

 * mem_cgroup_calc_reclaim_inactive() ... calculate the number of inactive pages
                                to be scanned in this priority in mem_cgroup.

 * mem_cgroup_all_unreclaimable() .. checks cgroup's page is all unreclaimable
                                     or not.
 * mem_cgroup_get_reclaim_priority() ...
 * mem_cgroup_note_reclaim_priority() ... record reclaim priority (temporal)
 * mem_cgroup_remember_reclaim_priority()
                             .... record reclaim priority as
                                  zone->prev_priority.
                                  This value is used for calc reclaim_mapped.

[akpm@linux-foundation.org: fix unused var warning]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

per-zone and reclaim enhancements for memory controller: calculate the number of pages to be scanned per cgroup

Define function for calculating the number of scan target on each Zone/LRU.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

per-zone and reclaim enhancements for memory controller: remember reclaim priority in memory cgroup

Functions to remember reclaim priority per cgroup (as zone->prev_priority)

[akpm@linux-foundation.org: build fixes]
[akpm@linux-foundation.org: more build fixes]
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Balbir Singh <balbir@linux.vnet.ibm.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Herbert Poetzl <herbert@13thfloor.at>
Cc: Kirill Korotaev <dev@sw.ru>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelianov <xemul@openvz.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>