Fix the following build failures:

arch/powerpc/platforms/embedded6xx/flipper-pic.c: In function 'flipper_pic_map':
arch/powerpc/platforms/embedded6xx/flipper-pic.c:105: error: implicit declaration of function 'get_irq_desc'

arch/powerpc/platforms/embedded6xx/hlwd-pic.c: In function 'hlwd_pic_map':
arch/powerpc/platforms/embedded6xx/hlwd-pic.c:98: error: implicit declaration of function 'get_irq_desc'

These failures are caused by the changes introduced in commit
"powerpc: Remove get_irq_desc()". The reason these drivers were not
updated is that they weren't merged yet.
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Fix the following build failures:

arch/powerpc/platforms/embedded6xx/hlwd-pic.c: In function 'hlwd_pic_irq_cascade':
arch/powerpc/platforms/embedded6xx/hlwd-pic.c:135: error: passing argument 1 of 'spin_lock' from incompatible pointer type
arch/powerpc/platforms/embedded6xx/hlwd-pic.c:137: error: passing argument 1 of 'spin_unlock' from incompatible pointer type
arch/powerpc/platforms/embedded6xx/hlwd-pic.c:145: error: passing argument 1 of 'spin_lock' from incompatible pointer type
arch/powerpc/platforms/embedded6xx/hlwd-pic.c:149: error: passing argument 1 of 'spin_unlock' from incompatible pointer type

These failures are caused by the changes introduced in commit
"genirq: Convert irq_desc.lock to raw_spinlock". The reason this driver
was not updated is that it wasn't merged yet.
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The retry logic in ug_putc() is broken.

If the TX fifo is not ready and the counter runs out it will have a
value of -1 and no transfer should be attempted. Also, a counter
with a value of 0 means that the TX fifo got ready in the last try
and the transfer should be attempted.
Reported-by: "Juha Leppanen" <juha_motorsportcom@luukku.com>
Signed-off-by: "Juha Leppanen" <juha_motorsportcom@luukku.com>
Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Since commit 57b150cc, desc->affinity
of an irq is changed after calling desc->chip->set_affinity.
Therefore we need to fix the irq_choose_cpu() not to depend on the
desc->affinity for new mask.
Signed-off-by: Jiajun Wu <b06378@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Commit d28513bc ("Fix bug in pagetable
cache cleanup with CONFIG_PPC_SUBPAGE_PROT"), itself a fix for
breakage caused by an earlier clean up patch of mine, contains a
stupid bug.  I changed the parameters of the subpage_protection()
function, but failed to update one of the callers.

This patch fixes it, and replaces a void * with a typed pointer so
that the compiler will warn on such an error in future.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The _ONSTACK variant should be used for on-stack completion,
otherwise it will break lockdep.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

On machines using the Apple U4 bridge (AKA IBM CPC945) PCIe interface such
as the latest generation G5 machines x16 slot or the x16 slot of the
PowerStation, MSIs are currently broken (and will oops when enabling).

This fixes the oops and implements proper support for those. Instead of
using the PCIe <-> HT bridge conversion, on such slots we need to use
a bunch of magic registers in the bridge as the MSI target, encoding
the interrupt number in the low bits of the address itself
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This patch fixes the handling of VSX alignment faults in little-endian
mode (the current code assumes the processor is in big-endian mode).

The patch also makes the handlers clear the top 8 bytes of the register
when handling an 8 byte VSX load.

This is based on 2.6.32.
Signed-off-by: Neil Campbell <neilc@linux.vnet.ibm.com>
Cc: <stable@kernel.org>
Acked-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The function name of cpumask_clear_cpu was not correct. Fortunately
nobody uses that code with hotplug yet :-)
Reported-by: Jin Qing <b24347@freescale.com>
Signed-off-by: Li Yang <leoli@freescale.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This time without the funny characters.

Fix following build errors generated with DEBUG=1

cc1: warnings being treated as errors
arch/powerpc/mm/hash_utils_64.c: In function 'htab_dt_scan_page_sizes':
arch/powerpc/mm/hash_utils_64.c:343: error: format '%04x' expects type 'unsigned int', but argument 4 has type 'long unsigned int'
arch/powerpc/mm/hash_utils_64.c:343: error: format '%08x' expects type 'unsigned int', but argument 5 has type 'long unsigned int'
arch/powerpc/mm/hash_utils_64.c: In function 'htab_initialize':
arch/powerpc/mm/hash_utils_64.c:666: error: format '%x' expects type 'unsigned int', but argument 4 has type 'long unsigned int'
... SNIP ...
Signed-off-by: Sachin Sant <sachinp@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Use the new unreachable() macro instead of for(;;);
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
CC: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: Paul Mackerras <paulus@samba.org>
CC: linuxppc-dev@ozlabs.org
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

And add the __acquires() and __releases() annotations, while at it.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

If an online-attempt on a CPU which has been offlined using H_CEDE
with an appropriate cede latency hint fails, don't panic.

Instead print the error message and let the __cpu_up() code notify the
CPU Hotplug framework of the failure, which in turn can notify the
other subsystem through CPU_UP_CANCELED.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Set need to call __set_pte_at() and not set_pte_at() from __change_page_attr()
since the later will perform checks with CONFIG_DEBUG_VM that aren't suitable
to the way we override an existing PTE. (More specifically, it doesn't let
you write over a present PTE).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Now we have high res timers there is less of a reason for a high HZ value.
Furthermore I think there a few reasons we should reduce HZ to 100:

- Timer interrupt overhead. While this overhead is small, there are
  applications that are very sensitive to jitter (eg some HPC apps).

- Issues with the timer wheel code. When coming out of NO_HZ idle we work our
  way through the timer code one tick at a time.  If we have been idle a long
  time, this adds up - I sometimes see milliseconds of time spent in that
  loop.

  Long term we should fix the timer wheel algorithm, but for now if we reduce
  HZ then we reduce the amount of work the timer code has to do when coming
  out of idle.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Token what? Lets save some space in our powerpc kernels and remove token
ring support.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Machines with acenic adapters are rare these days, so we may as well make it
a module. Cramfs is also very rarely used so we can make it a module.

Together this saves 143kB on a 64bit compile:

   text	   data	    bss	    dec	    hex	filename
8247176	1729404	1221988	11198568	 aae068	vmlinux~
8134997	1727588	1188836	11051421	 a8a19d	vmlinux
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

It's possible to set CONFIG_XICS without CONFIG_PCI_MSI. When that happens,
the kernel fails to build with

arch/powerpc/platforms/built-in.o: In function `.xics_startup':
xics.c:(.text+0x12f60): undefined reference to `.unmask_msi_irq' make: ***
[.tmp_vmlinux1] Error 1

Furthermore, as noted by Benjamin Herrenschmidt, "CONFIG_XICS should be
made invisible and selected by PSERIES."

This patch fixes PSERIES to select both options

Signed-off-by: Mel Gorman <mel[at]csn.ul.ie>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The wrong variable was returned in the case of an error.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

The Collaborative Memory Manager (CMM) module allocates individual pages
over time that are not migratable.  On a long running system this can
severely impact the ability to find enough pages to support a hotplug
memory remove operation.

This patch adds a memory isolation notifier and a memory hotplug notifier.
The memory isolation notifier will return the number of pages found in
the range specified.  This is used to determine if all of the used pages
in a pageblock are owned by the balloon (or other entities in the notifier
chain).  The hotplug notifier will free pages in the range which is to be
removed.  The priority of this hotplug notifier is low so that it will be
called near last, this helps avoids removing loaned pages in operations
that fail due to other handlers.

CMM activity will be halted when hotplug remove operations are active and
resume activity after a delay period to allow the hypervisor time to
adjust.
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Brian King <brking@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Gerald Schaefer <geralds@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Memory balloon drivers can allocate a large amount of memory which is not
movable but could be freed to accomodate memory hotplug remove.

Prior to calling the memory hotplug notifier chain the memory in the
pageblock is isolated.  Currently, if the migrate type is not
MIGRATE_MOVABLE the isolation will not proceed, causing the memory removal
for that page range to fail.

Rather than failing pageblock isolation if the migrateteype is not
MIGRATE_MOVABLE, this patch checks if all of the pages in the pageblock,
and not on the LRU, are owned by a registered balloon driver (or other
entity) using a notifier chain.  If all of the non-movable pages are owned
by a balloon, they can be freed later through the memory notifier chain
and the range can still be isolated in set_migratetype_isolate().
Signed-off-by: Robert Jennings <rcj@linux.vnet.ibm.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Brian King <brking@linux.vnet.ibm.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Gerald Schaefer <geralds@linux.vnet.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Merge branch 'cpumask-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus

* 'cpumask-cleanups' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-for-linus:
  cpumask: rename tsk_cpumask to tsk_cpus_allowed
  cpumask: don't recommend set_cpus_allowed hack in Documentation/cpu-hotplug.txt
  cpumask: avoid dereferencing struct cpumask
  cpumask: convert drivers/idle/i7300_idle.c to cpumask_var_t
  cpumask: use modern cpumask style in drivers/scsi/fcoe/fcoe.c
  cpumask: avoid deprecated function in mm/slab.c
  cpumask: use cpu_online in kernel/perf_event.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6:
  Keys: KEYCTL_SESSION_TO_PARENT needs TIF_NOTIFY_RESUME architecture support
  NOMMU: Optimise away the {dac_,}mmap_min_addr tests
  security/min_addr.c: make init_mmap_min_addr() static
  keys: PTR_ERR return of wrong pointer in keyctl_get_security()

Merge branch 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6

* 'omap-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap-2.6:
  OMAP3: serial - fix bug introduced in
  mfd: twl: fix twl4030 rename for remaining driver, board files
  USB ehci: replace mach header with plat
  omap3: Allow EHCI to be built on OMAP3

* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  hwmon: (w83627hf) Fix for "No such device"
  hwmon: (sht15) Off-by-one error in array index + incorrect constants
  hwmon: Add driver for VIA CPU core temperature
  hwmon: (smsc47m1) Enable device if needed
  hwmon: (smsc47m1) Fail module loading on error
  hwmon: (smsc47m1) Only request I/O ports we really use
  hwmon: New driver for AMD Family 10h/11h CPUs

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (40 commits)
  [SCSI] 3w-9xxx fix bug in sgl loading
  [SCSI] fcoe, libfc: adds enable/disable for fcoe interface
  [SCSI] libfc: reduce hold time on SCSI host lock
  [SCSI] libfc: remote port gets stuck in restart state without really restarting
  [SCSI] pm8001: misc code cleanup
  [SCSI] pm8001: enable read HBA SAS address from VPD
  [SCSI] pm8001: do not reset local sata as it will not be found if reset
  [SCSI] pm8001: bit set pm8001_ha->flags
  [SCSI] pm8001:fix potential NULL pointer dereference
  [SCSI] pm8001: set SSC down-spreading only to get less errors on some 6G device.
  [SCSI] pm8001: fix endian issues with SAS address
  [SCSI] pm8001: enhance error handle for IO patch
  [SCSI] pm8001: Fix for sata io circular lock dependency.
  [SCSI] hpsa: add driver for HP Smart Array controllers.
  [SCSI] cxgb3i: always use negative errno in case of error
  [SCSI] bnx2i: minor code cleanup and update driver version
  [SCSI] bnx2i: Task management ABORT TASK fixes
  [SCSI] bnx2i: update CQ arming algorith for 5771x chipsets
  [SCSI] bnx2i: Adjust sq_size module parametr to power of 2 only if a non-zero value is specified
  [SCSI] bnx2i: Add 5771E device support to bnx2i driver
  ...

* 'upstream' of git://ftp.linux-mips.org/pub/scm/upstream-linus: (71 commits)
  MIPS: Lasat: Fix botched changes to sysctl code.
  RTC: rtc-cmos.c: Fix warning on MIPS
  MIPS: Cleanup random differences beween lmo and Linus' kernel.
  MIPS: No longer hardwire CONFIG_EMBEDDED to y
  MIPS: Fix and enhance built-in kernel command line
  MIPS: eXcite: Remove platform.
  MIPS: Loongson: Cleanups of serial port support
  MIPS: Lemote 2F: Suspend CS5536 MFGPT Timer
  MIPS: Excite: move iodev_remove to .devexit.text
  MIPS: Lasat: Convert to proc_fops / seq_file
  MIPS: Cleanup signal code initialization
  MIPS: Modularize COP2 handling
  MIPS: Move EARLY_PRINTK to Kconfig.debug
  MIPS: Yeeloong 2F: Cleanup reset logic using the new ec_write function
  MIPS: Yeeloong 2F: Add LID open event as the wakeup event
  MIPS: Yeeloong 2F: Add basic EC operations
  MIPS: Move several variables from .bss to .init.data
  MIPS: Tracing: Make function graph tracer work with -mmcount-ra-address
  MIPS: Tracing: Reserve $12(t0) for mcount-ra-address of gcc 4.5
  MIPS: Tracing: Make ftrace for MIPS work without -fno-omit-frame-pointer
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: make sure fallocate properly starts a transaction
  Btrfs: make metadata chunks smaller
  Btrfs: Show discard option in /proc/mounts
  Btrfs: deny sys_link across subvolumes.
  Btrfs: fail mount on bad mount options
  Btrfs: don't add extent 0 to the free space cache v2
  Btrfs: Fix per root used space accounting
  Btrfs: Fix btrfs_drop_extent_cache for skip pinned case
  Btrfs: Add delayed iput
  Btrfs: Pass transaction handle to security and ACL initialization functions
  Btrfs: Make truncate(2) more ENOSPC friendly
  Btrfs: Make fallocate(2) more ENOSPC friendly
  Btrfs: Avoid orphan inodes cleanup during committing transaction
  Btrfs: Avoid orphan inodes cleanup while replaying log
  Btrfs: Fix disk_i_size update corner case
  Btrfs: Rewrite btrfs_drop_extents
  Btrfs: Add btrfs_duplicate_item
  Btrfs: Avoid superfluous tree-log writeout

* 'kmemleak' of git://linux-arm.org/linux-2.6:
  kmemleak: fix kconfig for crc32 build error
  kmemleak: Reduce the false positives by checking for modified objects
  kmemleak: Show the age of an unreferenced object
  kmemleak: Release the object lock before calling put_object()
  kmemleak: Scan the _ftrace_events section in modules
  kmemleak: Simplify the kmemleak_scan_area() function prototype
  kmemleak: Do not use off-slab management with SLAB_NOLEAKTRACE

* 'next-spi' of git://git.secretlab.ca/git/linux-2.6:
  spi: spi_txx9.c: use resource_size()
  spi: spi_sh_sci.c: use resource_size()
  spi: spi_mpc8xxx.c: use resource_size()
  spi: spi_bfin5xx.c: use resource_size()
  spi: atmel_spi.c: use resource_size()
  spi: Add s3c64xx SPI Controller driver
  atmel_spi: fix dma addr calculation for len > BUFFER_SIZE
  spi_s3c24xx: add FIQ pseudo-DMA support
  spi: controller driver for Designware SPI core
  spidev: add proper section markers
  spidev: use DECLARE_BITMAP instead of declaring the array

* 'for-linus' of git://git.o-hand.com/linux-rpurdie-backlight:
  backlight: mbp_nvidia_bl - add two more MacBookPro variants
  backlight: Pass device through notify callback in the pwm driver
  backlight: PTR_ERR return of wrong pointer in cr_backlight_probe()
  backlight: Constify struct backlight_ops
  backlight/thinkpad-acpi: issue backlight class events

Fix up trivial conflicts in thinkpad-acpi support (backlight support
already merged earlier).

* 'for-linus' of git://git.o-hand.com/linux-rpurdie-leds:
  leds: leds-pwm: Set led_classdev max_brightness
  leds: leds-lp3944.h - remove unneeded includes
  leds: use default-on trigger for Cobalt Qube
  leds: drivers/leds/leds-ss4200.c: fix return statement
  leds: leds-pca9532.h- indent with tabs, not spaces
  leds: Add LED class driver for regulator driven LEDs.
  leds: leds-cobalt-qube.c: use resource_size()
  leds: leds-cobalt-raq.c - use resource_size()
  leds: Add driver for ADP5520/ADP5501 MFD PMICs
  leds: Add driver for LT3593 controlled LEDs
  leds-ss4200: Check pci_enable_device return
  leds: leds-alix2c - take port address from MSR
  leds: LED driver for Intel NAS SS4200 series (v5)

* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm:
  PCMCIA: fix pxa2xx_lubbock modular build error
  [ARM] Update mach-types
  [ARM] pxa: fix no reference of cpu_is_pxa25x() in devices.c
  [ARM] pxa/cm-x300: add PWM backlight support
  revert "[ARM] pxa/cm-x300: add PWM backlight support"
  ARM: use flush_kernel_dcache_area() for dmabounce
  ARM: add size argument to __cpuc_flush_dcache_page
  ARM: 5848/1: kill flush_ioremap_region()
  ARM: cache-l2x0: make better use of background cache handling
  ARM: cache-l2x0: avoid taking spinlock for every iteration
  [ARM] Kirkwood: Add LaCie Network Space v2 support
  ARM: dove: fix the mm mmu flags of the pj4 procinfo

Fix kernel-doc warnings in printk.c:

Warning(kernel/printk.c:1422): No description found for parameter 'dumper'
Warning(kernel/printk.c:1422): Excess function parameter 'dump' description in 'kmsg_dump_register'
Warning(kernel/printk.c:1451): No description found for parameter 'dumper'
Warning(kernel/printk.c:1451): Excess function parameter 'dump' description in 'kmsg_dump_unregister'
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>

I added blk_run_backing_dev on page_cache_async_readahead so readahead I/O
is unpluged to improve throughput on especially RAID environment.

The normal case is, if page N become uptodate at time T(N), then T(N) <=
T(N+1) holds.  With RAID (and NFS to some degree), there is no strict
ordering, the data arrival time depends on runtime status of individual
disks, which breaks that formula.  So in do_generic_file_read(), just
after submitting the async readahead IO request, the current page may well
be uptodate, so the page won't be locked, and the block device won't be
implicitly unplugged:

               if (PageReadahead(page))
                        page_cache_async_readahead()
                if (!PageUptodate(page))
                                goto page_not_up_to_date;
                //...
page_not_up_to_date:
                lock_page_killable(page);

Therefore explicit unplugging can help.

Following is the test result with dd.

#dd if=testdir/testfile of=/dev/null bs=16384

-2.6.30-rc6
1048576+0 records in
1048576+0 records out
17179869184 bytes (17 GB) copied, 224.182 seconds, 76.6 MB/s

-2.6.30-rc6-patched
1048576+0 records in
1048576+0 records out
17179869184 bytes (17 GB) copied, 206.465 seconds, 83.2 MB/s

(7Disks RAID-0 Array)

-2.6.30-rc6
1054976+0 records in
1054976+0 records out
17284726784 bytes (17 GB) copied, 212.233 seconds, 81.4 MB/s

-2.6.30-rc6-patched
1054976+0 records out
17284726784 bytes (17 GB) copied, 198.878 seconds, 86.9 MB/s

(7Disks RAID-5 Array)

The patch was found to improve performance with the SCST scsi target
driver.  See
http://sourceforge.net/mailarchive/forum.php?thread_name=a0272b440906030714g67eabc5k8f847fb1e538cc62%40mail.gmail.com&forum_name=scst-devel

[akpm@linux-foundation.org: unbust comment layout]
[akpm@linux-foundation.org: "fix" CONFIG_BLOCK=n]
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Acked-by: Wu Fengguang <fengguang.wu@intel.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: Ronald <intercommit@gmail.com>
Cc: Bart Van Assche <bart.vanassche@gmail.com>
Cc: Vladislav Bolkhovitin <vst@vlnb.net>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

RTC core won't allow wakeup alarms to be set if RTC devices' parent (i.e.
i2c_client or spi_device) isn't wakeup capable.

For I2C devices there is I2C_CLIENT_WAKE flag exists that we can pass via
board info, and if set, I2C core will initialize wakeup capability.  For
SPI devices there is no such flag at all.

I believe that it's not platform code responsibility to allow or disallow
wakeups, instead, drivers themselves should set the capability if a device
can trigger wakeups.

That's what drivers/base/power/sysfs.c says:

 * It is the responsibility of device drivers to enable (or disable)
 * wakeup signaling as part of changing device power states, respecting
 * the policy choices provided through the driver model.

I2C and SPI RTC devices send wakeup events via interrupt lines, so we
should set the wakeup capability if IRQ is routed.

Ideally we should also check irq for wakeup capability before setting
device's capability, i.e.

	if (can_irq_wake(irq))
		device_set_wakeup_capable(&client->dev, 1);

But there is no can_irq_wake() call exist, and it is not that trivial to
implement it for all interrupts controllers and complex/cascaded setups.

drivers/base/power/sysfs.c also covers these cases:

 * Devices may not be able to generate wakeup events from all power
 * states.  Also, the events may be ignored in some configurations;
 * for example, they might need help from other devices that aren't
 * active

So there is no guarantee that wakeup will actually work, and so I think
there is no point in being pedantic wrt checking IRQ wakeup capability.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Cc: Ben Dooks <ben-linux@fluff.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Alessandro Zummo <a.zummo@towertech.it>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>