Eric Lee / smarc-fsl-linux-kernel

27 Jul, 2011

1 commit

  • 60063497a   atomic: use <linux/atomic.h> ... Browse Code »

    This allows us to move duplicated code in
    (atomic_inc_not_zero() for now) to

    Signed-off-by: Arun Sharma
    Reviewed-by: Eric Dumazet
    Cc: Ingo Molnar
    Cc: David Miller
    Cc: Eric Dumazet
    Acked-by: Mike Frysinger
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Arun Sharma
     

21 Jul, 2011

1 commit

  • 4582c0a48   mutex: Make mutex_destroy() an inline function ... Browse Code »

    The non-debug variant of mutex_destroy is a no-op, currently
    implemented as a macro which does nothing. This approach fails
    to check the type of the parameter, so an error would only show
    when debugging gets enabled. Using an inline function instead,
    offers type checking for earlier bug catching.

    Signed-off-by: Jean Delvare
    Cc: Peter Zijlstra
    Link: http://lkml.kernel.org/r/20110716174200.41002352@endymion.delvare
    Signed-off-by: Ingo Molnar

    Jean Delvare
     

25 May, 2011

1 commit

  • e4c70a662   lockdep, mutex: provide mutex_lock_nest_lock ... Browse Code »

    In order to convert i_mmap_lock to a mutex we need a mutex equivalent to
    spin_lock_nest_lock(), thus provide the mutex_lock_nest_lock() annotation.

    As with spin_lock_nest_lock(), mutex_lock_nest_lock() allows annotation of
    the locking pattern where an outer lock serializes the acquisition order
    of nested locks. That is, if every time you lock multiple locks A, say A1
    and A2 you first acquire N, the order of acquiring A1 and A2 is
    irrelevant.

    Signed-off-by: Peter Zijlstra
    Cc: Benjamin Herrenschmidt
    Cc: David Miller
    Cc: Martin Schwidefsky
    Cc: Russell King
    Cc: Paul Mundt
    Cc: Jeff Dike
    Cc: Richard Weinberger
    Cc: Tony Luck
    Cc: KAMEZAWA Hiroyuki
    Cc: Hugh Dickins
    Cc: Mel Gorman
    Cc: KOSAKI Motohiro
    Cc: Nick Piggin
    Cc: Namhyung Kim
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Peter Zijlstra
     

14 Apr, 2011

1 commit

  • c6eb3dda2   mutex: Use p->on_cpu for the adaptive spin ... Browse Code »

    Since we now have p->on_cpu unconditionally available, use it to
    re-implement mutex_spin_on_owner.

    Requested-by: Thomas Gleixner
    Reviewed-by: Frank Rowand
    Cc: Mike Galbraith
    Cc: Nick Piggin
    Cc: Linus Torvalds
    Cc: Andrew Morton
    Signed-off-by: Ingo Molnar
    Signed-off-by: Peter Zijlstra
    Link: http://lkml.kernel.org/r/20110405152728.826338173@chello.nl

    Peter Zijlstra
     

26 Nov, 2010

1 commit

  • 335d7afbf   mutexes, sched: Introduce arch_mutex_cpu_relax() ... Browse Code »

    The spinning mutex implementation uses cpu_relax() in busy loops as a
    compiler barrier. Depending on the architecture, cpu_relax() may do more
    than needed in this specific mutex spin loops. On System z we also give
    up the time slice of the virtual cpu in cpu_relax(), which prevents
    effective spinning on the mutex.

    This patch replaces cpu_relax() in the spinning mutex code with
    arch_mutex_cpu_relax(), which can be defined by each architecture that
    selects HAVE_ARCH_MUTEX_CPU_RELAX. The default is still cpu_relax(), so
    this patch should not affect other architectures than System z for now.

    Signed-off-by: Gerald Schaefer
    Signed-off-by: Peter Zijlstra
    LKML-Reference:
    Signed-off-by: Ingo Molnar

    Gerald Schaefer
     

03 Sep, 2010

1 commit

30 Apr, 2009

1 commit

  • a511e3f96   mutex: add atomic_dec_and_mutex_lock(), fix ... Browse Code »

    include/linux/mutex.h:136: warning: 'mutex_lock' declared inline after being called
    include/linux/mutex.h:136: warning: previous declaration of 'mutex_lock' was here

    uninline it.

    [ Impact: clean up and uninline, address compiler warning ]

    Signed-off-by: Andrew Morton
    Cc: Al Viro
    Cc: Christoph Hellwig
    Cc: Eric Paris
    Cc: Paul Mackerras
    Cc: Peter Zijlstra
    LKML-Reference:
    Signed-off-by: Ingo Molnar

    Andrew Morton
     

29 Apr, 2009

1 commit

  • b1fca2663   mutex: add atomic_dec_and_mutex_lock() ... Browse Code »

    Much like the atomic_dec_and_lock() function in which we take an hold a
    spin_lock if we drop the atomic to 0 this function takes and holds the
    mutex if we dec the atomic to 0.

    Signed-off-by: Eric Paris
    Signed-off-by: Peter Zijlstra
    Cc: Paul Mackerras
    Orig-LKML-Reference:
    Signed-off-by: Ingo Molnar

    Eric Paris
     

15 Jan, 2009

1 commit

  • 0d66bf6d3   mutex: implement adaptive spinning ... Browse Code »

    Change mutex contention behaviour such that it will sometimes busy wait on
    acquisition - moving its behaviour closer to that of spinlocks.

    This concept got ported to mainline from the -rt tree, where it was originally
    implemented for rtmutexes by Steven Rostedt, based on work by Gregory Haskins.

    Testing with Ingo's test-mutex application (http://lkml.org/lkml/2006/1/8/50)
    gave a 345% boost for VFS scalability on my testbox:

    # ./test-mutex-shm V 16 10 | grep "^avg ops"
    avg ops/sec: 296604

    # ./test-mutex-shm V 16 10 | grep "^avg ops"
    avg ops/sec: 85870

    The key criteria for the busy wait is that the lock owner has to be running on
    a (different) cpu. The idea is that as long as the owner is running, there is a
    fair chance it'll release the lock soon, and thus we'll be better off spinning
    instead of blocking/scheduling.

    Since regular mutexes (as opposed to rtmutexes) do not atomically track the
    owner, we add the owner in a non-atomic fashion and deal with the races in
    the slowpath.

    Furthermore, to ease the testing of the performance impact of this new code,
    there is means to disable this behaviour runtime (without having to reboot
    the system), when scheduler debugging is enabled (CONFIG_SCHED_DEBUG=y),
    by issuing the following command:

    # echo NO_OWNER_SPIN > /debug/sched_features

    This command re-enables spinning again (this is also the default):

    # echo OWNER_SPIN > /debug/sched_features

    Signed-off-by: Peter Zijlstra
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     

31 Oct, 2008

1 commit

09 Feb, 2008

1 commit

07 Dec, 2007

1 commit

17 Oct, 2007

1 commit

12 Oct, 2007

1 commit

  • e4564f79d   lockdep: fixup mutex annotations ... Browse Code »

    The fancy mutex_lock fastpath has too many indirections to track the caller
    hence all contentions are perceived to come from mutex_lock().

    Avoid this by explicitly not using the fastpath code (it was disabled already
    anyway).

    Signed-off-by: Peter Zijlstra
    Signed-off-by: Ingo Molnar

    Peter Zijlstra
     

10 May, 2007

1 commit

27 Jan, 2007

1 commit

09 Dec, 2006

1 commit

  • d63a5a74d   [PATCH] lockdep: avoid lockdep warning in md ... Browse Code »

    md_open takes ->reconfig_mutex which causes lockdep to complain. This
    (normally) doesn't have deadlock potential as the possible conflict is with a
    reconfig_mutex in a different device.

    I say "normally" because if a loop were created in the array->member hierarchy
    a deadlock could happen. However that causes bigger problems than a deadlock
    and should be fixed independently.

    So we flag the lock in md_open as a nested lock. This requires defining
    mutex_lock_interruptible_nested.

    Cc: Ingo Molnar
    Acked-by: Peter Zijlstra
    Acked-by: Ingo Molnar
    Signed-off-by: Neil Brown
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    NeilBrown
     

08 Dec, 2006

1 commit

04 Jul, 2006

2 commits

  • ef5d4707b   [PATCH] lockdep: prove mutex locking correctness ... Browse Code »

    Use the lock validator framework to prove mutex locking correctness.

    Signed-off-by: Ingo Molnar
    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ingo Molnar
     
  • 9a11b49a8   [PATCH] lockdep: better lock debugging ... Browse Code »

    Generic lock debugging:

    - generalized lock debugging framework. For example, a bug in one lock
    subsystem turns off debugging in all lock subsystems.

    - got rid of the caller address passing (__IP__/__IP_DECL__/etc.) from
    the mutex/rtmutex debugging code: it caused way too much prototype
    hackery, and lockdep will give the same information anyway.

    - ability to do silent tests

    - check lock freeing in vfree too.

    - more finegrained debugging options, to allow distributions to
    turn off more expensive debugging features.

    There's no separate 'held mutexes' list anymore - but there's a 'held locks'
    stack within lockdep, which unifies deadlock detection across all lock
    classes. (this is independent of the lockdep validation stuff - lockdep first
    checks whether we are holding a lock already)

    Here are the current debugging options:

    CONFIG_DEBUG_MUTEXES=y
    CONFIG_DEBUG_LOCK_ALLOC=y

    which do:

    config DEBUG_MUTEXES
    bool "Mutex debugging, basic checks"

    config DEBUG_LOCK_ALLOC
    bool "Detect incorrect freeing of live mutexes"

    Signed-off-by: Ingo Molnar
    Signed-off-by: Arjan van de Ven
    Signed-off-by: Andrew Morton
    Signed-off-by: Linus Torvalds

    Ingo Molnar
     

12 Jan, 2006

1 commit

  • a4fc7ab1d   [PATCH] fix/simplify mutex debugging code ... Browse Code »

    Let's switch mutex_debug_check_no_locks_freed() to take (addr, len) as
    arguments instead, since all its callers were just calculating the 'to'
    address for themselves anyway... (and sometimes doing so badly).

    Signed-off-by: David Woodhouse
    Acked-by: Ingo Molnar
    Signed-off-by: Linus Torvalds

    David Woodhouse
     

11 Jan, 2006

1 commit

10 Jan, 2006

1 commit