linux-toradex.git/lib/bitmap.c, branch v3.17-rc2

lib: bitmap: add missing mask in bitmap_andnot

2014-08-07T01:01:27+00:00

Apparently, bitmap_andnot is supposed to return whether the new bitmap
is empty.  But it didn't take potential garbage bits in the last word
into account.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: add missing mask in bitmap_and

2014-08-07T01:01:27+00:00

Apparently, bitmap_and is supposed to return whether the new bitmap is
empty.  But it didn't take potential garbage bits in the last word into
account.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: micro-optimize bitmap_allocate_region

2014-08-07T01:01:26+00:00

__reg_op(..., REG_OP_ALLOC) always returns 0, so we might as well use that
and save an instruction.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: change parameter of bitmap_*_region to unsigned

2014-08-07T01:01:26+00:00

Changing the pos parameter of __reg_op to unsigned allows the compiler
to generate slightly smaller and simpler code.  Also update its callers
bitmap_*_region to receive and pass unsigned int.  The return types of
bitmap_find_free_region and bitmap_allocate_region are still int to
allow a negative error code to be returned.  An int is certainly capable
of representing any realistic return value.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: fix typo in kerneldoc for bitmap_pos_to_ord

2014-08-07T01:01:26+00:00

A few lines above, it was stated that positions for non-set bits are
mapped to -1, which is obviously also what the code does.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: simplify bitmap_parselist

2014-08-07T01:01:26+00:00

We want len to be the index of the first '\n', or the length of the
string if there is no newline.  This is a good example of the usefulness
of strchrnul().  Use that instead, thus eliminating a branch and a call
to strlen().

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: make the start index of bitmap_clear unsigned

2014-08-07T01:01:26+00:00

The compiler can generate slightly smaller and simpler code when it
knows that "start" is non-negative.

Also, use the names "start" and "len" for the two parameters for
consistency with bitmap_set.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: make the start index of bitmap_set unsigned

2014-08-07T01:01:26+00:00

The compiler can generate slightly smaller and simpler code when it
knows that "start" is non-negative.

Also, use the names "start" and "len" for the two parameters in both
header file and implementation, instead of the previous mix.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: make nbits parameter of bitmap_weight unsigned

2014-08-07T01:01:26+00:00

The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative.  Since no-one passes a negative
bit-count, this shouldn't affect the semantics.

I didn't change the return type, since that might change the semantics
of some expression containing a call to bitmap_weight(). Certainly an
int is capable of holding the result.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: bitmap: make nbits parameter of bitmap_subset unsigned

2014-08-07T01:01:26+00:00

The compiler can generate slightly smaller and simpler code when it
knows that "nbits" is non-negative.  Since no-one passes a negative
bit-count, this shouldn't affect the semantics.

Signed-off-by: Rasmus Villemoes 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds