linux-toradex.git/include/asm-generic/atomic.h, branch v4.6-rc3

atomic, arch: Audit atomic_{read,set}()

2015-09-23T07:54:28+00:00

This patch makes sure that atomic_{read,set}() are at least
{READ,WRITE}_ONCE().

We already had the 'requirement' that atomic_read() should use
ACCESS_ONCE(), and most archs had this, but a few were lacking.
All are now converted to use READ_ONCE().

And, by a symmetry and general paranoia argument, upgrade atomic_set()
to use WRITE_ONCE().

Signed-off-by: Peter Zijlstra (Intel) 
Cc: Andrew Morton 
Cc: Dmitry Vyukov 
Cc: Linus Torvalds 
Cc: Paul E. McKenney 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: james.hogan@imgtec.com
Cc: linux-kernel@vger.kernel.org
Cc: oleg@redhat.com
Cc: will.deacon@arm.com
Signed-off-by: Ingo Molnar

atomic: Collapse all atomic_{set,clear}_mask definitions

2015-07-27T12:06:24+00:00

Move the now generic definitions of atomic_{set,clear}_mask() into
linux/atomic.h to avoid endless and pointless repetition.

Also, provide an atomic_andnot() wrapper for those few archs that can
implement that.

Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Thomas Gleixner

atomic: Provide atomic_{or,xor,and}

2015-07-27T12:06:24+00:00

Implement atomic logic ops -- atomic_{or,xor,and}.

These will replace the atomic_{set,clear}_mask functions that are
available on some archs.

Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Thomas Gleixner

atomic: Prepare generic atomic implementation for logic ops

2015-07-27T12:06:21+00:00

Clean up the #ifdef guards a bit to prepare for architectures to
supply their own logic ops.

Signed-off-by: Peter Zijlstra (Intel) 
Signed-off-by: Thomas Gleixner

locking,arch: Use ACCESS_ONCE() instead of cast to volatile in atomic_read()

2014-10-03T04:06:23+00:00

Use the much more reader friendly ACCESS_ONCE() instead of the cast to volatile.
This is purely a stylistic change.

Signed-off-by: Pranith Kumar 
Acked-by: Jesper Nilsson 
Acked-by: Hans-Christian Egtvedt 
Acked-by: Max Filippov 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Linus Torvalds 
Cc: linux-arch@vger.kernel.org
Link: http://lkml.kernel.org/r/1411482607-20948-1-git-send-email-bobby.prani@gmail.com
Signed-off-by: Ingo Molnar

locking,arch: Rewrite generic atomic support

2014-08-14T10:48:14+00:00

Rewrite generic atomic support to only require cmpxchg(), generate all
other primitives from that.

Furthermore reduce the endless repetition for all these primitives to
a few CPP macros. This way we get more for less lines.

Signed-off-by: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20140508135852.940119622@infradead.org
Cc: Arnd Bergmann 
Cc: David Howells 
Cc: Paul E. McKenney 
Cc: David S. Miller 
Cc: Linus Torvalds 
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar

arch: Prepare for smp_mb__{before,after}_atomic()

2014-04-18T09:40:30+00:00

Since the smp_mb__{before,after}*() ops are fundamentally dependent on
how an arch can implement atomics it doesn't make sense to have 3
variants of them. They must all be the same.

Furthermore, the 3 variants suggest they're only valid for those 3
atomic ops, while we have many more where they could be applied.

So move away from
smp_mb__{before,after}_{atomic,clear}_{dec,inc,bit}() and reduce the
interface to just the two: smp_mb__{before,after}_atomic().

This patch prepares the way by introducing default implementations in
asm-generic/barrier.h that default to a full barrier and providing
__deprecated inlines for the previous 6 barriers if they're not
provided by the arch.

This should allow for a mostly painless transition (lots of deprecated
warns in the interim).

Signed-off-by: Peter Zijlstra 
Acked-by: Paul E. McKenney 
Link: http://lkml.kernel.org/n/tip-wr59327qdyi9mbzn6x937s4e@git.kernel.org
Cc: Arnd Bergmann 
Cc: "Chen, Gong" 
Cc: John Sullivan 
Cc: Linus Torvalds 
Cc: Mauro Carvalho Chehab 
Cc: Srinivas Pandruvada 
Cc: "Theodore Ts'o" 
Cc: linux-arch@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

asm-generic: move cmpxchg*_local defs to cmpxchg.h

2013-03-13T05:11:05+00:00

asm/cmpxchg.h can be included on its own and needs to be self-consistent.
The definitions for the cmpxchg*_local macros, as such, need to be part
of this file.

This fixes a build issue on OpenRISC since the system.h smashing patch
96f951edb1f1bdbbc99b0cd458f9808bb83d58ae that introdued the direct inclusion
asm/cmpxchg.h into linux/llist.h.

CC: David Howells 
Signed-off-by: Jonas Bonn 
Acked-by: Arnd Bergmann

Remove all #inclusions of asm/system.h

2012-03-28T17:30:03+00:00

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*.*\n!!' `grep -Irl '^#\s*include\s*' *`

Signed-off-by: David Howells

Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h

2012-03-28T17:30:03+00:00

Make asm-generic/cmpxchg.h #include asm-generic/cmpxchg-local.h as all arch
files that #include the former also #include the latter.  See:

	grep -rl asm-generic/cmpxchg-local[.]h arch/ | sort > b
	grep -rl asm-generic/cmpxchg[.]h arch/ | sort > a
	comm a b

This simplifies the disintegration of asm-generic/system.h for arches that
don't have their own.

Signed-off-by: David Howells 
Acked-by: Arnd Bergmann