Fix for http://bugzilla.kernel.org/show_bug.cgi?id=9355

cpuidle always used to fallback to C2 if there is some bm activity while
entering C3. But, presence of C2 is not always guaranteed. Change cpuidle
algorithm to detect a safe_state to fallback in case of bm_activity and
use that state instead of C2.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit e5a16b1f9eec0af7cfa0830304b41c1c0833cf9f
Author: Len Brown <len.brown@intel.com>
Date:   Tue Oct 2 23:44:44 2007 -0400

    cpuidle: shrink diff

    processor_idle.c |  440 +++++++++++++++++++++++++++++++++++++++++--
    1 file changed, 429 insertions(+), 11 deletions(-)
Signed-off-by: NLen Brown <len.brown@intel.com>

commit dfbb9d5aedfb18848a3e0d6f6e3e4969febb209c
Author: Len Brown <len.brown@intel.com>
Date:   Wed Sep 26 02:17:55 2007 -0400

    cpuidle: reduce diff size

    Reduces the cpuidle processor_idle.c diff vs 2.6.22 from this
     processor_idle.c | 2006 ++++++++++++++++++++++++++-----------------
     1 file changed, 1219 insertions(+), 787 deletions(-)

    to this:
     processor_idle.c |  502 +++++++++++++++++++++++++++++++++++++++----
     1 file changed, 458 insertions(+), 44 deletions(-)

    ...for the purpose of making the cpuilde patch less invasive
    and easier to review.

    no functional changes.  build tested only.
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 889172fc915f5a7fe20f35b133cbd205ce69bf6c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Sep 13 13:40:05 2007 -0700

    cpuidle: Retain old ACPI policy for !CONFIG_CPU_IDLE

    Retain the old policy in processor_idle, so that when CPU_IDLE is not
    configured, old C-state policy will still be used. This provides a
    clean gradual migration path from old ACPI policy to new cpuidle
    based policy.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 9544a8181edc7ecc33b3bfd69271571f98ed08bc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Sep 13 13:39:17 2007 -0700

    cpuidle: Configure governors by default

    Quoting Len "Do not give an option to users to shoot themselves in the foot".

    Remove the configurability of ladder and menu governors as they are
    needed for default policy of cpuidle. That way users will not be able to
    have cpuidle without any policy loosing all C-state power savings.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 8975059a2c1e56cfe83d1bcf031bcf4cb39be743
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:27:07 2007 -0400

    CPUIDLE: load ACPI properly when CPUIDLE is disabled

    Change the registration return codes for when CPUIDLE
    support is not compiled into the kernel.  As a result, the ACPI
    processor driver will load properly even if CPUIDLE is unavailable.
    However, it may be possible to cleanup the ACPI processor driver further
    and eliminate some dead code paths.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit e0322e2b58dd1b12ec669bf84693efe0dc2414a8
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:26:06 2007 -0400

    CPUIDLE: remove cpuidle_get_bm_activity()

    Remove cpuidle_get_bm_activity() and updates governors
    accordingly.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 18a6e770d5c82ba26653e53d240caa617e09e9ab
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:58 2007 -0400

    CPUIDLE: max_cstate fix

    Currently max_cstate is limited to 0, resulting in no idle processor
    power management on ACPI platforms.  This patch restores the value to
    the array size.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 1fdc0887286179b40ce24bcdbde663172e205ef0
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:40 2007 -0400

    CPUIDLE: handle BM detection inside the ACPI Processor driver

    Update the ACPI processor driver to detect BM activity and
    limit state entry depth internally, rather than exposing such
    requirements to CPUIDLE.  As a result, CPUIDLE can drop this
    ACPI-specific interface and become more platform independent.  BM
    activity is now handled much more aggressively than it was in the
    original implementation, so some testing coverage may be needed to
    verify that this doesn't introduce any DMA buffer under-run issues.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 0ef38840db666f48e3cdd2b769da676c57228dd9
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:25:14 2007 -0400

    CPUIDLE: menu governor updates

    Tweak the menu governor to more effectively handle non-timer
    break events.  Non-timer break events are detected by comparing the
    actual sleep time to the expected sleep time.  In future revisions, it
    may be more reliable to use the timer data structures directly.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit bb4d74fca63fa96cf3ace644b15ae0f12b7df5a1
Author: Adam Belay <abelay@novell.com>
Date:   Tue Aug 21 18:24:40 2007 -0400

    CPUIDLE: fix 'current_governor' sysfs entry

    Allow the "current_governor" sysfs entry to properly handle
    input terminated with '\n'.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit df3c71559bb69b125f1a48971bf0d17f78bbdf47
Author: Len Brown <len.brown@intel.com>
Date:   Sun Aug 12 02:00:45 2007 -0400

    cpuidle: fix IA64 build (again)
Signed-off-by: NLen Brown <len.brown@intel.com>

commit a02064579e3f9530fd31baae16b1fc46b5a7bca8
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:39:27 2007 -0400

    cpuidle: Remove support for runtime changing of max_cstate

    Remove support for runtime changeability of max_cstate. Drivers can use
    use latency APIs.

    max_cstate can still be used as a boot time option and dmi override.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 0912a44b13adf22f5e3f607d263aed23b4910d7e
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:39:16 2007 -0400

    cpuidle: Remove ACPI cstate_limit calls from ipw2100

    ipw2100 already has code to use accetable_latency interfaces to limit the
    C-state. Remove the calls to acpi_set_cstate_limit and acpi_get_cstate_limit
    as they are redundant.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit c649a76e76be6bff1fd770d0a775798813a3f6e0
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Sun Aug 12 01:35:39 2007 -0400

    cpuidle: compile fix for pause and resume functions

    Fix the compilation failure when cpuidle is not compiled in.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: NAdam Belay <adam.belay@novell.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 2305a5920fb8ee6ccec1c62ade05aa8351091d71
Author: Adam Belay <abelay@novell.com>
Date:   Thu Jul 19 00:49:00 2007 -0400

    cpuidle: re-write

    Some portions have been rewritten to make the code cleaner and lighter
    weight.  The following is a list of changes:

    1.) the state name is now included in the sysfs interface
    2.) detection, hotplug, and available state modifications are handled by
    CPUIDLE drivers directly
    3.) the CPUIDLE idle handler is only ever installed when at least one
    cpuidle_device is enabled and ready
    4.) the menu governor BM code no longer overflows
    5.) the sysfs attributes are now printed as unsigned integers, avoiding
    negative values
    6.) a variety of other small cleanups

    Also, Idle drivers are no longer swappable during runtime through the
    CPUIDLE sysfs inteface.  On i386 and x86_64 most idle handlers (e.g.
    poll, mwait, halt, etc.) don't benefit from an infrastructure that
    supports multiple states, so I think using a more general case idle
    handler selection mechanism would be cleaner.
Signed-off-by: NAdam Belay <abelay@novell.com>
Acked-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Acked-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit df25b6b56955714e6e24b574d88d1fd11f0c3ee5
Author: Len Brown <len.brown@intel.com>
Date:   Tue Jul 24 17:08:21 2007 -0400

    cpuidle: fix IA64 buid
Signed-off-by: NLen Brown <len.brown@intel.com>

commit fd6ada4c14488755ff7068860078c437431fbccd
Author: Adrian Bunk <bunk@stusta.de>
Date:   Mon Jul 9 11:33:13 2007 -0700

    cpuidle: static

    make cpuidle_replace_governor() static
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit c1d4a2cebcadf2429c0c72e1d29aa2a9684c32e0
Author: Adrian Bunk <bunk@stusta.de>
Date:   Tue Jul 3 00:54:40 2007 -0400

    cpuidle: static

    This patch makes the needlessly global struct menu_governor static.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit dbf8780c6e8d572c2c273da97ed1cca7608fd999
Author: Andrew Morton <akpm@linux-foundation.org>
Date:   Tue Jul 3 00:49:14 2007 -0400

    export symbol tick_nohz_get_sleep_length

    ERROR: "tick_nohz_get_sleep_length" [drivers/cpuidle/governors/menu.ko] undefined!
    ERROR: "tick_nohz_get_idle_jiffies" [drivers/cpuidle/governors/menu.ko] undefined!

    And please be sure to get your changes to core kernel suitably reviewed.

    Cc: Adam Belay <abelay@novell.com>
    Cc: Venki Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Ingo Molnar <mingo@elte.hu>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: john stultz <johnstul@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 29f0e248e7017be15f99febf9143a2cef00b2961
Author: Andrew Morton <akpm@linux-foundation.org>
Date:   Tue Jul 3 00:43:04 2007 -0400

    tick.h needs hrtimer.h

    It uses hrtimers.
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit e40cede7d63a029e92712a3fe02faee60cc38fb4
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:40:34 2007 -0400

    cpuidle: first round of documentation updates

    Documentation changes based on Pavel's feedback.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 83b42be2efece386976507555c29e7773a0dfcd1
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:39:25 2007 -0400

    cpuidle: add rating to the governors and pick the one with highest rating by default

    Introduce a governor rating scheme to pick the right governor by default.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit d2a74b8c5e8f22def4709330d4bfc4a29209b71c
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:38:08 2007 -0400

    cpuidle: make cpuidle sysfs driver governor switch off by default

    Make default cpuidle sysfs to show current_governor and current_driver in
    read-only mode.  More elaborate available_governors and available_drivers with
    writeable current_governor and current_driver interface only appear with
    "cpuidle_sysfs_switch" boot parameter.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 1f60a0e80bf83cf6b55c8845bbe5596ed8f6307b
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:37:00 2007 -0400

    cpuidle: menu governor: change the early break condition

    Change the C-state early break out algorithm in menu governor.

    We only look at early breakouts that result in wakeups shorter than idle
    state's target_residency.  If such a breakout is frequent enough, eliminate
    the particular idle state upto a timeout period.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 45a42095cf64b003b4a69be3ce7f434f97d7af51
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:35:38 2007 -0400

    cpuidle: fix uninitialized variable in sysfs routine

    Fix the uninitialized usage of ret.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 80dca7cdba3e6ee13eae277660873ab9584eb3be
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:34:16 2007 -0400

    cpuidle: reenable /proc/acpi//power interface for the time being

    Keep /proc/acpi/processor/CPU*/power around for a while as powertop depends
    on it. It will be marked deprecated and removed in future. powertop can use
    cpuidle interfaces instead.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 589c37c2646c5e3813a51255a5ee1159cb4c33fc
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Jul 3 00:32:37 2007 -0400

    cpuidle: menu governor and hrtimer compile fix

    Compile fix for menu governor.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 0ba80bd9ab3ed304cb4f19b722e4cc6740588b5e
Author: Len Brown <len.brown@intel.com>
Date:   Thu May 31 22:51:43 2007 -0400

    cpuidle: build fix - cpuidle vs ipw2100 module

    ERROR: "acpi_set_cstate_limit" [drivers/net/wireless/ipw2100.ko] undefined!
Signed-off-by: NLen Brown <len.brown@intel.com>

commit d7d8fa7f96a7f7682be7c6cc0cc53fa7a18c3b58
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:47:07 2007 -0400

    cpuidle: add the 'menu' governor

    Here is my first take at implementing an idle PM governor that takes
    full advantage of NO_HZ.  I call it the 'menu' governor because it
    considers the full list of idle states before each entry.

    I've kept the implementation fairly simple.  It attempts to guess the
    next residency time and then chooses a state that would meet at least
    the break-even point between power savings and entry cost.  To this end,
    it selects the deepest idle state that satisfies the following
    constraints:
         1. If the idle time elapsed since bus master activity was detected
            is below a threshold (currently 20 ms), then limit the selection
            to C2-type or above.
         2. Do not choose a state with a break-even residency that exceeds
            the expected time remaining until the next timer interrupt.
         3. Do not choose a state with a break-even residency that exceeds
            the elapsed time between the last pair of break events,
            excluding timer interrupts.

    This governor has an advantage over "ladder" governor because it
    proactively checks how much time remains until the next timer interrupt
    using the tick infrastructure.  Also, it handles device interrupt
    activity more intelligently by not including timer interrupts in break
    event calculations.  Finally, it doesn't make policy decisions using the
    number of state entries, which can have variable residency times (NO_HZ
    makes these potentially very large), and instead only considers sleep
    time deltas.

    The menu governor can be selected during runtime using the cpuidle sysfs
    interface like so:
    "echo "menu" > /sys/devices/system/cpu/cpuidle/current_governor"
Signed-off-by: NAdam Belay <abelay@novell.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit a4bec7e65aa3b7488b879d971651cc99a6c410fe
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:47:03 2007 -0400

    cpuidle: export time until next timer interrupt using NO_HZ

    Expose information about the time remaining until the next
    timer interrupt expires by utilizing the dynticks infrastructure.
    Also modify the main idle loop to allow dynticks to handle
    non-interrupt break events (e.g. DMA).  Finally, expose sleep ticks
    information to external code.  Thomas Gleixner is responsible for much
    of the code in this patch.  However, I've made some additional changes,
    so I'm probably responsible if there are any bugs or oversights :)
Signed-off-by: NAdam Belay <abelay@novell.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 2929d8996fbc77f41a5ff86bb67cdde3ca7d2d72
Author: Adam Belay <abelay@novell.com>
Date:   Sat Mar 24 03:46:58 2007 -0400

    cpuidle: governor API changes

    This patch prepares cpuidle for the menu governor.  It adds an optional
    stage after idle state entry to give the governor an opportunity to
    check why the state was exited.  Also it makes sure the idle loop
    returns after each state entry, allowing the appropriate dynticks code
    to run.
Signed-off-by: NAdam Belay <abelay@novell.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 3a7fd42f9825c3b03e364ca59baa751bb350775f
Author: Venki Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Apr 26 00:03:59 2007 -0700

    cpuidle: hang fix

    Prevent hang on x86-64, when ACPI processor driver is added as a module on
    a system that does not support C-states.

    x86-64 expects all idle handlers to enable interrupts before returning from
    idle handler.  This is due to enter_idle(), exit_idle() races.  Make
    cpuidle_idle_call() confirm to this when there is no pm_idle_old.

    Also, cpuidle look at the return values of attch_driver() and set
    current_driver to NULL if attach fails on all CPUs.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 4893339a142afbd5b7c01ffadfd53d14746e858e
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:09 2007 +0800

    cpuidle: add support for max_cstate limit

    With CPUIDLE framework, the max_cstate (to limit max cpu c-state)
    parameter is ingored. Some systems require it to ignore C2/C3
    and some drivers like ipw require it too.
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 43bbbbe1cb998cbd2df656f55bb3bfe30f30e7d1
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:13 2007 +0800

    cpuidle: add cpuidle_fore_redetect_devices API

    add cpuidle_force_redetect_devices API,
    which forces all CPU redetect idle states.
    Next patch will use it.
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit d1edadd608f24836def5ec483d2edccfb37b1d19
Author: Shaohua Li <shaohua.li@intel.com>
Date:   Thu Apr 26 10:40:01 2007 +0800

    cpuidle: fix sysfs related issue

    Fix the cpuidle sysfs issue.
    a. make kobject dynamicaly allocated
    b. fixed sysfs init issue to avoid suspend/resume issue
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 7169a5cc0d67b263978859672e86c13c23a5570d
Author: Randy Dunlap <randy.dunlap@oracle.com>
Date:   Wed Mar 28 22:52:53 2007 -0400

    cpuidle: 1-bit field must be unsigned

    A 1-bit bitfield has no room for a sign bit.
    drivers/cpuidle/governors/ladder.c:54:16: error: dubious bitfield without explicit `signed' or `unsigned'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 4658620158dc2fbd9e4bcb213c5b6fb5d05ba7d4
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Mar 28 22:52:41 2007 -0400

    cpuidle: fix boot hang

    Patch for cpuidle boot hang reported by Larry Finger here.
    http://www.ussg.iu.edu/hypermail/linux/kernel/0703.2/2025.htmlSigned-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Larry Finger <larry.finger@lwfinger.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit c17e168aa6e5fe3851baaae8df2fbc1cf11443a9
Author: Len Brown <len.brown@intel.com>
Date:   Wed Mar 7 04:37:53 2007 -0500

    cpuidle: ladder does not depend on ACPI

    build fix for CONFIG_ACPI=n

    In file included from drivers/cpuidle/governors/ladder.c:21:
    include/acpi/processor.h:88: error: expected specifier-qualifier-list before ‘acpi_integer’
    include/acpi/processor.h:106: error: expected specifier-qualifier-list before ‘acpi_integer’
    include/acpi/processor.h:168: error: expected specifier-qualifier-list before ‘acpi_handle’
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 8c91d958246bde68db0c3f0c57b535962ce861cb
Author: Adrian Bunk <bunk@stusta.de>
Date:   Tue Mar 6 02:29:40 2007 -0800

    cpuidle: make code static

    This patch makes the following needlessly global code static:
    - driver.c: __cpuidle_find_driver()
    - governor.c: __cpuidle_find_governor()
    - ladder.c: struct ladder_governor
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
    Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Adam Belay <abelay@novell.com>
    Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 0c39dc3187094c72c33ab65a64d2017b21f372d2
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Wed Mar 7 02:38:22 2007 -0500

    cpu_idle: fix build break

    This patch fixes a build breakage with !CONFIG_HOTPLUG_CPU and
    CONFIG_CPU_IDLE.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 8112e3b115659b07df340ef170515799c0105f82
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Tue Mar 6 02:29:39 2007 -0800

    cpuidle: build fix for !CPU_IDLE

    Fix the compile issues when CPU_IDLE is not configured.
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
    Cc: Adam Belay <abelay@novell.com>
    Cc: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 1eb4431e9599cd25e0d9872f3c2c8986821839dd
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:54:57 2007 -0800

    cpuidle take2: Basic documentation for cpuidle

    Documentation for cpuidle infrastructure
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAdam Belay <abelay@novell.com>
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit ef5f15a8b79123a047285ec2e3899108661df779
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:54:03 2007 -0800

    cpuidle take2: Hookup ACPI C-states driver with cpuidle

    Hookup ACPI C-states onto generic cpuidle infrastructure.

    drivers/acpi/procesor_idle.c is now a ACPI C-states driver that registers as
    a driver in cpuidle infrastructure and the policy part is removed from
    drivers/acpi/processor_idle.c. We use governor in cpuidle instead.
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NAdam Belay <abelay@novell.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

commit 987196fa82d4db52c407e8c9d5dec884ba602183
Author: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Date:   Thu Feb 22 13:52:57 2007 -0800

    cpuidle take2: Core cpuidle infrastructure

    Announcing 'cpuidle', a new CPU power management infrastructure to manage
    idle CPUs in a clean and efficient manner.
    cpuidle separates out the drivers that can provide support for multiple types
    of idle states and policy governors that decide on what idle state to use
    at run time.
    A cpuidle driver can support multiple idle states based on parameters like
    varying power consumption, wakeup latency, etc (ACPI C-states for example).
    A cpuidle governor can be usage model specific (laptop, server,
    laptop on battery etc).
    Main advantage of the infrastructure being, it allows independent development
    of drivers and governors and allows for better CPU power management.

    A huge thanks to Adam Belay and Shaohua Li who were part of this mini-project
    since its beginning and are greatly responsible for this patchset.

    This patch:

    Core cpuidle infrastructure.
    Introduces a new abstraction layer for cpuidle:
    * which manages drivers that can support multiple idles states. Drivers
      can be generic or particular to specific hardware/platform
    * allows pluging in multiple policy governors that can take idle state policy
      decision
    * The core also has a set of sysfs interfaces with which administrato can know
      about supported drivers and governors and switch them at run time.
Signed-off-by: NAdam Belay <abelay@novell.com>
Signed-off-by: NShaohua Li <shaohua.li@intel.com>
Signed-off-by: NVenkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>
Signed-off-by: NLen Brown <len.brown@intel.com>

All the current page_mkwrite() implementations also set the page dirty. Which
results in the set_page_dirty_balance() call to _not_ call balance, because the
page is already found dirty.

This allows us to dirty a _lot_ of pages without ever hitting
balance_dirty_pages().  Not good (tm).

Force a balance call if ->page_mkwrite() was successful.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit a3d38402 aka
"[AX.25]: Fix unchecked rose_add_loopback_neigh uses"
transformed rose_loopback_neigh var into statically allocated one.
However, on unload it will be kfree's which can't work.

Steps to reproduce:

	modprobe rose
	rmmod rose

BUG: unable to handle kernel NULL pointer dereference at virtual address 00000008
 printing eip:
c014c664
*pde = 00000000
Oops: 0000 [#1]
PREEMPT DEBUG_PAGEALLOC
Modules linked in: rose ax25 fan ufs loop usbhid rtc snd_intel8x0 snd_ac97_codec ehci_hcd ac97_bus uhci_hcd thermal usbcore button processor evdev sr_mod cdrom
CPU:    0
EIP:    0060:[<c014c664>]    Not tainted VLI
EFLAGS: 00210086   (2.6.23-rc9 #3)
EIP is at kfree+0x48/0xa1
eax: 00000556   ebx: c1734aa0   ecx: f6a5e000   edx: f7082000
esi: 00000000   edi: f9a55d20   ebp: 00200287   esp: f6a5ef28
ds: 007b   es: 007b   fs: 0000  gs: 0033  ss: 0068
Process rmmod (pid: 1823, ti=f6a5e000 task=f7082000 task.ti=f6a5e000)
Stack: f9a55d20 f9a5200c 00000000 00000000 00000000 f6a5e000 f9a5200c f9a55a00 
       00000000 bf818cf0 f9a51f3f f9a55a00 00000000 c0132c60 65736f72 00000000 
       f69f9630 f69f9528 c014244a f6a4e900 00200246 f7082000 c01025e6 00000000 
Call Trace:
 [<f9a5200c>] rose_rt_free+0x1d/0x49 [rose]
 [<f9a5200c>] rose_rt_free+0x1d/0x49 [rose]
 [<f9a51f3f>] rose_exit+0x4c/0xd5 [rose]
 [<c0132c60>] sys_delete_module+0x15e/0x186
 [<c014244a>] remove_vma+0x40/0x45
 [<c01025e6>] sysenter_past_esp+0x8f/0x99
 [<c012bacf>] trace_hardirqs_on+0x118/0x13b
 [<c01025b6>] sysenter_past_esp+0x5f/0x99
 =======================
Code: 05 03 1d 80 db 5b c0 8b 03 25 00 40 02 00 3d 00 40 02 00 75 03 8b 5b 0c 8b 73 10 8b 44 24 18 89 44 24 04 9c 5d fa e8 77 df fd ff <8b> 56 08 89 f8 e8 84 f4 fd ff e8 bd 32 06 00 3b 5c 86 60 75 0f 
EIP: [<c014c664>] kfree+0x48/0xa1 SS:ESP 0068:f6a5ef28
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It turns out that there are a few other five-second timers in the
kernel, and if the timers get in sync, the load-average can get
artificially inflated by events that just happen to coincide.

So just offset the load average calculation it by a timer tick.

Noticed by Anders Boström, for whom the coincidence started triggering
on one of his machines with the JBD jiffies rounding code (JBD is one of
the subsystems that also end up using a 5-second timer by default).
Tested-by: NAnders Boström <anders@bostrom.dyndns.org>
Cc: Chuck Ebbert <cebbert@redhat.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It is ok to call prefetch() function with NULL argument, as specifically
commented in include/linux/prefetch.h.  But in standard C, it is invalid
to dereference NULL pointer (see C99 standard 6.5.3.2 paragraph 4 and
note #84).

prefetch() has a memory reference for its argument.

Newer gcc versions (4.3 and above) will use that to conclude that "x"
argument is non-null and thus wreaking havok everywhere prefetch() was
inlined.

Fixed by removing cast and changing asm constraint.

[ It seems in theory gcc 4.2 could miscompile this too; although no
  cases known.  In 2.6.24 we should probably switch to
  __builtin_prefetch() instead, but this is a simpler fix for now.
				-- AK ]
Signed-off-by: NSerge Belyshev <belyshev@depni.sinp.msu.ru>
Signed-off-by: NAndi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cc: Kalle Pokki <kalle.pokki@iki.fi>
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Blackfin arch: gpio pinmux and resource allocation API required by BF537 on chip ethernet mac driver
Signed-off-by: NMichael Hennerich <michael.hennerich@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

They contain 64-bit instructions so wouldn't work on 32-bit kernels or
32-bit hardware.  Since there are no users, blow them away.  They
probably were only ever created because there are atomic_sub_if_positive
and atomic_dec_if_positive which exist only for sake of semaphores.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

A "cleanup" almost two years ago deleted the old definition from
<asm/fcntl.h>, so asm-generic/fcntl.h defaulted it to the the same
value as FASYNC ...   which happened to be the wrong thing.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The comment being removed by this patch is incorrect and misleading.

In the following situation:

	1. load  ...
	2. store 1 -> X
	3. wmb
	4. rmb
	5. load  a <- Y
	6. store ...

4 will only ensure ordering of 1 with 5.
3 will only ensure ordering of 2 with 6.

Further, a CPU with strictly in-order stores will still only provide that
2 and 6 are ordered (effectively, it is the same as a weakly ordered CPU
with wmb after every store).

In all cases, 5 may still be executed before 2 is visible to other CPUs!

The additional piece of the puzzle that mb() provides is the store/load
ordering, which fundamentally cannot be achieved with any combination of
rmb()s and wmb()s.

This can be an unexpected result if one expected any sort of global ordering
guarantee to barriers (eg. that the barriers themselves are sequentially
consistent with other types of barriers).  However sfence or lfence barriers
need only provide an ordering partial ordering of memory operations -- Consider
that wmb may be implemented as nothing more than inserting a special barrier
entry in the store queue, or, in the case of x86, it can be a noop as the store
queue is in order. And an rmb may be implemented as a directive to prevent
subsequent loads only so long as their are no previous outstanding loads (while
there could be stores still in store queues).

I can actually see the occasional load/store being reordered around lfence on
my core2. That doesn't prove my above assertions, but it does show the comment
is wrong (unless my program is -- can send it out by request).

So:
   mb() and smp_mb() always have and always will require a full mfence
   or lock prefixed instruction on x86.  And we should remove this comment.
Signed-off-by: NNick Piggin <npiggin@suse.de>
Cc: Paul McKenney <paulmck@us.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Based upon a report and initial patch by Peter Lieven.

tcp4_md5sig_key and tcp6_md5sig_key need to start with
the exact same members as tcp_md5sig_key.  Because they
are both cast to that type by tcp_v{4,6}_md5_do_lookup().

Unfortunately tcp{4,6}_md5sig_key use a u16 for the key
length instead of a u8, which is what tcp_md5sig_key
uses.  This just so happens to work by accident on
little-endian, but on big-endian it doesn't.

Instead of casting, just place tcp_md5sig_key as the first member of
the address-family specific structures, adjust the access sites, and
kill off the ugly casts.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The __pa() for those did assume that all symbols have XKPHYS values and
the math fails for any other address range.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

The __pa() for those did assume that all symbols have XKPHYS values and
the math fails for any other address range.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This reverts commit 184c44d2.

As noted by Dave Jones:
   "Linus, please revert the above cset.  It doesn't seem to be
    necessary (it was added to fix a miscompile in 'make allnoconfig'
    which doesn't seem to be repeatable with it reverted) and actively
   breaks the ARM SA1100 framebuffer driver."
Requested-by: NDave Jones <davej@redhat.com>
Cc: Russell King <rmk+lkml@arm.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit e66485d7, since
Rafael Wysocki noticed that the change only works for his in -mm, not in
mainline (and that both "noapictimer" _and_ "apicmaintimer" are broken
on his hardware, but that's apparently not a regression, just a symptom
of the same issue that causes the automatic apic timer disable to not
work).

It turns out that it really doesn't work correctly on x86-64, since
x86-64 doesn't use the generic clock events for timers yet.

Thanks to Rafal for testing, and here's the ugly details on x86-64 as
per Thomas:

  "I just looked into the code and the logic vs.  noapictimer on SMP is
   completely broken.

   On i386 the noapictimer option not only disables the local APIC
   timer, it also registers the CPUs for broadcasting via IPI on SMP
   systems.

   The x86-64 code uses the broadcast only when the local apic timer is
   active, i.e.  "noapictimer" is not on the command line.  This defeats
   the whole purpose of "noapictimer".  It should be there to make boxen
   work, where the local APIC timer actually has a hardware problem,
   e.g.  the nx6325.

   The current implementation of x86_64 only fixes the ACPI c-states
   related problem where the APIC timer stops in C3(2), nothing else.

   On nx6325 and other AMD X2 equipped systems which have the C1E
   enabled we run into the following:

   PIT keeps jiffies (and the system) running, but the local APIC timer
   interrupts can get out of sync due to this C1E effect.

   I don't think this is a critical problem, but it is wrong
   nevertheless.

   I think it's safe to revert the C1E patch and postpone the fix to the
   clock events conversion."

On further reflection, Thomas noted:

   "It's even worse than I thought on the first check:

    "noapictimer" on the command line of an SMP box prevents _ONLY_ the
    boot CPU apic timer from being used.  But the secondary CPU is still
    unconditionally setting up the APIC timer and uses the non
    calibrated variable calibration_result, which is of course 0, to
    setup the APIC timer.  Wreckage guaranteed."

so we'll just have to wait for the x86 merge to hopefully fix this up
for x86-64.
Tested-and-requested-by: NRafael J. Wysocki <rjw@sisk.pl>
Acked-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

commit 3556ddfa titled

 [PATCH] x86-64: Disable local APIC timer use on AMD systems with C1E

solves a problem with AMD dual core laptops e.g. HP nx6325 (Turion 64
X2) with C1E enabled:

When both cores go into idle at the same time, then the system switches
into C1E state, which is basically the same as C3. This stops the local
apic timer.

This was debugged right after the dyntick merge on i386 and despite the
patch title it fixes only the 32 bit path.

x86_64 is still missing this fix. It seems that mainline is not really
affected by this issue, as the PIT is running and keeps jiffies
incrementing, but that's just waiting for trouble.

-mm suffers from this problem due to the x86_64 high resolution timer
patches.

This is a quick and dirty port of the i386 code to x86_64.

I spent quite a time with Rafael to debug the -mm / hrt wreckage until
someone pointed us to this. I really had forgotten that we debugged this
half a year ago already.

Sigh, is it just me or is there something yelling arch/x86 into my ear?
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It gets pointer to fastcall function, expects a pointer to normal
one and calls the sucker.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If ADDIP is enabled, when an ASCONF chunk is received with ASCONF
paramter length set to zero, this will cause infinite loop.
By the way, if an malformed ASCONF chunk is received, will cause
processing to access memory without verifying.

This is because of not check the validity of parameters in ASCONF chunk.
This patch fixed this.
Signed-off-by: NWei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>

While processing OOTB chunks as well as chunks with an invalid
length of 0, it was possible to SCTP to get wedged inside an
infinite loop because we didn't catch the condition correctly,
or didn't mark the packet for discard correctly.
This work is based on original findings and work by
Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>

Signed-off-by: NAlexey Starikovskiy <astarikovskiy@suse.de>
Acked-by: NRafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NLen Brown <len.brown@intel.com>

Issue reported and original patch by Kevin Kissel, cleaner (imho)
implementation by me.
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

device_suspend() calls ACPI suspend functions, which seems to have undesired
side effects on lower idle C-states. It took me some time to realize that
especially the VAIO BIOSes (both Andrews jinxed UP and my elfstruck SMP one)
show this effect. I'm quite sure that other bug reports against suspend/resume
about turning the system into a brick have the same root cause.

After fishing in the dark for quite some time, I realized that removing the ACPI
processor module before suspend (this removes the lower C-state functionality)
made the problem disappear. Interestingly enough the propability of having a
bricked box is influenced by various factors (interrupts, size of the ram image,
...). Even adding a bunch of printks in the wrong places made the problem go
away. The previous periodic tick implementation simply pampered over the
problem, which explains why the dyntick / clockevents changes made this more
prominent.

We avoid complex functionality during the boot process and we have to do the
same during suspend/resume. It is a similar scenario and equaly fragile.

Add suspend / resume functions to the ACPI processor code and disable the lower
idle C-states across suspend/resume. Fall back to the default idle
implementation (halt) instead.
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Tested-by: NAndrew Morton <akpm@linux-foundation.org>
Cc: Len Brown <lenb@kernel.org>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

When compiling the Blackfin kernel, checksyscalls.pl will report lots of missing syscalls warnings.
This patch will add some missing syscalls which make sense on Blackfin arch

After appling this patch, toolchain should be rebuilt. Then recompiling the kernel with the new
toolchain.
Signed-off-by: NBryan Wu <bryan.wu@analog.com>

Add minimum support for the Blackfin relocations, since we don't have
enough space in each reloc.  The idea is to store a value with one
relocation so that subsequent ones can access it.

Actually, this patch is required for Blackfin.  Currently if BINFMT_FLAT is
enabled, git-tree kernel will fail to compile.
Signed-off-by: NBernd Schmidt <bernd.schmidt@analog.com>
Signed-off-by: NBryan Wu <bryan.wu@analog.com>
Cc: David McCullough <davidm@snapgear.com>
Cc: Greg Ungerer <gerg@snapgear.com>
Cc: Miles Bader <miles.bader@necel.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

This reverts commit 34feb2c8.

Suresh Siddha points out that this one breaks the fundamental
requirement that you cannot free page table pages before the TLB caches
are flushed.  The quicklists do not give the same kinds of guarantees
that the mmu_gather structure does, at least not in NUMA configurations.
Requested-by: NSuresh Siddha <suresh.b.siddha@intel.com>
Acked-by: NAndi Kleen <ak@suse.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Lameter <clameter@sgi.com>
Cc: Asit Mallick <asit.k.mallick@intel.com>
Cc: Tony Luck <tony.luck@intel.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This simplifies signalfd code, by avoiding it to remain attached to the
sighand during its lifetime.

In this way, the signalfd remain attached to the sighand only during
poll(2) (and select and epoll) and read(2).  This also allows to remove
all the custom "tsk == current" checks in kernel/signal.c, since
dequeue_signal() will only be called by "current".

I think this is also what Ben was suggesting time ago.

The external effect of this, is that a thread can extract only its own
private signals and the group ones.  I think this is an acceptable
behaviour, in that those are the signals the thread would be able to
fetch w/out signalfd.
Signed-off-by: NDavide Libenzi <davidel@xmailserver.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

add /proc/sys/kernel/sched_compat_yield to make sys_sched_yield()
more agressive, by moving the yielding task to the last position
in the rbtree.

with sched_compat_yield=0:

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
  2539 mingo     20   0  1576  252  204 R   50  0.0   0:02.03 loop_yield
  2541 mingo     20   0  1576  244  196 R   50  0.0   0:02.05 loop

with sched_compat_yield=1:

   PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
  2584 mingo     20   0  1576  248  196 R   99  0.0   0:52.45 loop
  2582 mingo     20   0  1576  256  204 R    0  0.0   0:00.00 loop_yield
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>

Add a workaround to address warnings generated on the "n" constraint by
GCC 3.3 and below.
Signed-off-by: NMaciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

This patch proposes fixes to the reference counting of memory policy in the
page allocation paths and in show_numa_map().  Extracted from my "Memory
Policy Cleanups and Enhancements" series as stand-alone.

Shared policy lookup [shmem] has always added a reference to the policy,
but this was never unrefed after page allocation or after formatting the
numa map data.

Default system policy should not require additional ref counting, nor
should the current task's task policy.  However, show_numa_map() calls
get_vma_policy() to examine what may be [likely is] another task's policy.
The latter case needs protection against freeing of the policy.

This patch adds a reference count to a mempolicy returned by
get_vma_policy() when the policy is a vma policy or another task's
mempolicy.  Again, shared policy is already reference counted on lookup.  A
matching "unref" [__mpol_free()] is performed in alloc_page_vma() for
shared and vma policies, and in show_numa_map() for shared and another
task's mempolicy.  We can call __mpol_free() directly, saving an admittedly
inexpensive inline NULL test, because we know we have a non-NULL policy.

Handling policy ref counts for hugepages is a bit trickier.
huge_zonelist() returns a zone list that might come from a shared or vma
'BIND policy.  In this case, we should hold the reference until after the
huge page allocation in dequeue_hugepage().  The patch modifies
huge_zonelist() to return a pointer to the mempolicy if it needs to be
unref'd after allocation.

Kernel Build [16cpu, 32GB, ia64] - average of 10 runs:

		w/o patch	w/ refcount patch
	    Avg	  Std Devn	   Avg	  Std Devn
Real:	 100.59	    0.38	 100.63	    0.43
User:	1209.60	    0.37	1209.91	    0.31
System:   81.52	    0.42	  81.64	    0.34
Signed-off-by: NLee Schermerhorn <lee.schermerhorn@hp.com>
Acked-by: NAndi Kleen <ak@suse.de>
Cc: Christoph Lameter <clameter@sgi.com>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

It turned out, that the user namespace is released during the do_exit() in
exit_task_namespaces(), but the struct user_struct is released only during the
put_task_struct(), i.e.  MUCH later.

On debug kernels with poisoned slabs this will cause the oops in
uid_hash_remove() because the head of the chain, which resides inside the
struct user_namespace, will be already freed and poisoned.

Since the uid hash itself is required only when someone can search it, i.e.
when the namespace is alive, we can safely unhash all the user_struct-s from
it during the namespace exiting.  The subsequent free_uid() will complete the
user_struct destruction.

For example simple program

   #include <sched.h>

   char stack[2 * 1024 * 1024];

   int f(void *foo)
   {
   	return 0;
   }

   int main(void)
   {
   	clone(f, stack + 1 * 1024 * 1024, 0x10000000, 0);
   	return 0;
   }

run on kernel with CONFIG_USER_NS turned on will oops the
kernel immediately.

This was spotted during OpenVZ kernel testing.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAlexey Dobriyan <adobriyan@openvz.org>
Acked-by: N"Serge E. Hallyn" <serue@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Surprisingly, but (spotted by Alexey Dobriyan) the uid hash still uses
list_heads, thus occupying twice as much place as it could.  Convert it to
hlist_heads.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAlexey Dobriyan <adobriyan@openvz.org>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Recent changes to the timekeeping code broke support for the PowerPC 601
processor which doesn't have the usual timebase facility but a slightly
different thing called (yuck) the RTC.

This fixes it, boot tested on an old 601 based PowerMac 7200.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

When CONFIG_ISA is disabled, the isa_driver support will not be compiled
in.  Define stubs so that we don't get link-time errors.
Signed-off-by: NMatthew Wilcox <matthew@wil.cx>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds an optimised version of skb_cow that avoids the copy if
the header can be modified even if the rest of the payload is cloned.

This can be used in encapsulating paths where we only need to modify the
header.  As it is, this can be used in PPPOE and bridging.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since the sctp_sockaddr_entry is now RCU enabled as part of
the patch to synchronize sctp_localaddr_list, it makes sense to
change all handling of these entries to RCU.  This includes the
sctp_bind_addrs structure and it's list of bound addresses.

This list is currently protected by an external rw_lock and that
looks like an overkill.  There are only 2 writers to the list:
bind()/bindx() calls, and BH processing of ASCONF-ACK chunks.
These are already seriealized via the socket lock, so they will
not step on each other.  These are also relatively rare, so we
should be good with RCU.

The readers are varied and they are easily converted to RCU.
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NSridhar Samdurala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sctp_localaddr_list is modified dynamically via NETDEV_UP
and NETDEV_DOWN events, but there is not synchronization
between writer (even handler) and readers.  As a result,
the readers can access an entry that has been freed and
crash the sytem.
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: NSridhar Samdurala <sri@us.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As noted by Al Viro, when we try to call prom_set_trap_table()
in the SMP trampoline code we try to take the PROM call spinlock
which doesn't work because the current thread pointer isn't
valid yet and lockdep depends upon that being correct.

Furthermore, we cannot set the current thread pointer register
because it can't be properly dereferenced until we return from
prom_set_trap_table().  Kernel TLB misses only work after that
call.

So do the PROM call to set the trap table directly instead of
going through the OBP library C code, and thus avoid the lock
altogether.

These calls are guarenteed to be serialized fully.

Since there are now no calls to the prom_set_trap_table{_sun4v}()
library functions, they can be deleted.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Revert b5438582 and add
no_pci_devices() check to avoid crash due to early calling of
pci_get_class().
Signed-off-by: NAtsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>