linux-stable.git/arch/tile/include/asm/atomic_32.h, branch linux-4.2.y

arch,tile: Convert smp_mb__*()

2014-04-18T12:20:45+00:00

Implement the new smp_mb__* ops as per the old ones.

Signed-off-by: Peter Zijlstra 
Acked-by: Paul E. McKenney 
Acked-by: Chris Metcalf 
Link: http://lkml.kernel.org/n/tip-euuabnf5a3u23fy4fq8m3jcg@git.kernel.org
Cc: Akinobu Mita 
Cc: Chen Gang 
Cc: Geert Uytterhoeven 
Cc: Linus Torvalds 
Cc: Mathieu Desnoyers 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

tile: include: asm: use 'long long' instead of 'u64' for atomic64_t and its related functions

2013-09-27T20:08:56+00:00

atomic* value is signed value, and atomic* functions need also process
signed value (parameter value, and return value), so use 'long long'
instead of 'u64'.

After replacement, it will also fix a bug for atomic64_add_negative():
"u64 is never less than 0".

The modifications are:

  in vim, use "1,% s/\/long long/g" command.
  remove redundant '__aligned(8)'.
  be sure of 80 (and macro '\') columns limitation after replacement.

Signed-off-by: Chen Gang 
Signed-off-by: Chris Metcalf  [re-instated const cast]

tile: rework

2013-09-06T17:06:25+00:00

The macrology in cmpxchg.h was designed to allow arbitrary pointer
and integer values to be passed through the routines.  To support
cmpxchg() on 64-bit values on the 32-bit tilepro architecture, we
used the idiom "(typeof(val))(typeof(val-val))".  This way, in the
"size 8" branch of the switch, when the underlying cmpxchg routine
returns a 64-bit quantity, we cast it first to a typeof(val-val)
quantity (i.e. size_t if "val" is a pointer) with no warnings about
casting between pointers and integers of different sizes, then cast
onwards to typeof(val), again with no warnings.  If val is not a
pointer type, the additional cast is a no-op.  We can't replace the
typeof(val-val) cast with (for example) unsigned long, since then if
"val" is really a 64-bit type, we cast away the high bits.

HOWEVER, this fails with current gcc (through 4.7 at least) if "val"
is a pointer to an incomplete type.  Unfortunately gcc isn't smart
enough to realize that "val - val" will always be a size_t type
even if it's an incomplete type pointer.

Accordingly, I've reworked the way we handle the casting.  We have
given up the ability to use cmpxchg() on 64-bit values on tilepro,
which is OK in the kernel since we should use cmpxchg64() explicitly
on such values anyway.  As a result, I can just use simple "unsigned
long" casts internally.

As I reworked it, I realized it would be cleaner to move the
architecture-specific conditionals for cmpxchg and xchg out of the
atomic.h headers and into cmpxchg, and then use the cmpxchg() and
xchg() primitives directly in atomic.h and elsewhere.  This allowed
the cmpxchg.h header to stand on its own without relying on the
implicit include of it that is performed by .
It also allowed collapsing the atomic_xchg/atomic_cmpxchg routines
from atomic_{32,64}.h into atomic.h.

I improved the tests that guard the allowed size of the arguments
to the routines to use a __compiletime_error() test.  (By avoiding
the use of BUILD_BUG, I could include cmpxchg.h into bitops.h as
well and use the macros there, which is otherwise impossible due
to include order dependency issues.)

The tilepro _atomic_xxx internal methods were previously set up to
take atomic_t and atomic64_t arguments, which isn't as convenient
with the new model, so I modified them to take int or u64 arguments,
which is consistent with how they used the arguments internally
anyway, so provided some nice simplification there too.

Signed-off-by: Chris Metcalf

tile: remove support for TILE64

2013-09-03T18:53:29+00:00

This chip is no longer being actively developed for (it was superceded
by the TILEPro64 in 2008), and in any case the existing compiler and
toolchain in the community do not support it.  It's unlikely that the
kernel works with TILE64 at this point as the configuration has not been
tested in years.  The support is also awkward as it requires maintaining
a significant number of ifdefs.  So, just remove it altogether.

Signed-off-by: Chris Metcalf

arch/tile: optimize get_user/put_user and friends

2012-05-25T16:48:23+00:00

Use direct load/store for the get_user/put_user.

Previously, we would call out to a helper routine that would do the
appropriate thing and then return, handling the possible exception
internally.  Now we inline the load or store, along with a "we succeeded"
indication in a register; if the load or store faults, we write a
"we failed" indication into the same register and then return to the
following instruction.  This is more efficient and gives us more compact
code, as well as being more in line with what other architectures do.

The special futex assembly source file for TILE-Gx also disappears in
this change; we just use the same inlining idiom there as well, putting
the appropriate atomic operations directly into futex_atomic_op_inuser()
(and thus into the FUTEX_WAIT function).

The underlying atomic copy_from_user, copy_to_user functions were
renamed using the (cryptic) x86 convention as copy_from_user_ll and
copy_to_user_ll.

Signed-off-by: Chris Metcalf

arch/tile: revert comment for atomic64_add_unless().

2012-04-02T16:00:15+00:00

It still returns whether @v was not @u, not the old value,
unlike __atomic_add_unless().

Signed-off-by: Chris Metcalf 
Acked-by: Arun Sharma

Disintegrate asm/system.h for Tile

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

Disintegrate asm/system.h for Tile.

Signed-off-by: David Howells 
Acked-by: Chris Metcalf

atomic: move atomic_add_unless to generic code

2011-07-26T23:49:47+00:00

This is in preparation for more generic atomic primitives based on
__atomic_add_unless.

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

atomic: use

2011-07-26T23:49:47+00:00

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

arch/tile: use better definitions of xchg() and cmpxchg()

2011-05-20T02:55:49+00:00

These definitions use a ({}) construct to avoid some cases where
we were getting warnings about unused return values.  We also
promote the definition to the common , since it applies
to both the 32- and 64-bit atomics.

In addition, define __HAVE_ARCH_CMPXCHG for TILE-Gx since it has
efficient direct atomic instructions.

Signed-off-by: Chris Metcalf