linux-toradex.git/lib/div64.c, branch v4.4.106

remove abs64()

2015-11-09T23:11:24+00:00

Switch everything to the new and more capable implementation of abs().
Mainly to give the new abs() a bit of a workout.

Cc: Michal Nazarewicz 
Cc: John Stultz 
Cc: Ingo Molnar 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Masami Hiramatsu 
Cc: Peter Zijlstra 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

lib: correct link to the original source for div64_u64

2015-03-06T22:19:27+00:00

The code refers to an invalid url
http://www.hackersdelight.org/HDcode/newCode/divDouble.c.txt

The correct url is
http://www.hackersdelight.org/hdcodetxt/divDouble.c.txt

Signed-off-by: Heinrich Schuchardt 
Signed-off-by: Jiri Kosina

math64: New separate div64_u64_rem helper

2013-08-23T13:02:14+00:00

Commit f792685006274a850e6cc0ea9ade275ccdfc90bc ("math64: New
div64_u64_rem helper") implemented div64_u64 in terms of div64_u64_rem.
But div64_u64_rem was removed because it slowed down div64_u64 (and
there were no other users of div64_u64_rem).

Device Mapper's I/O statistics support has a need for div64_u64_rem;
reintroduce this helper as a separate method that doesn't slow down
div64_u64, especially on 32-bit systems.

Signed-off-by: Mike Snitzer 
Cc: Stanislaw Gruszka 
Cc: Ingo Molnar 
Cc: Frederic Weisbecker 
Cc: Mikulas Patocka 
Signed-off-by: Alasdair G Kergon

Revert "math64: New div64_u64_rem helper"

2013-04-30T17:13:05+00:00

This reverts commit f792685006274a850e6cc0ea9ade275ccdfc90bc.

The cputime scaling code was changed/fixed and does not need the
div64_u64_rem() primitive anymore. It has no other users, so let's
remove them.

Signed-off-by: Stanislaw Gruszka 
Cc: Frederic Weisbecker 
Cc: rostedt@goodmis.org
Cc: Linus Torvalds 
Cc: Dave Hansen 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/1367314507-9728-4-git-send-email-sgruszka@redhat.com
Signed-off-by: Ingo Molnar

math64: New div64_u64_rem helper

2013-03-13T17:03:27+00:00

Provide an extended version of div64_u64() that
also returns the remainder of the division.

We are going to need this to refine the cputime
scaling code.

Signed-off-by: Frederic Weisbecker 
Cc: Stanislaw Gruszka 
Cc: Steven Rostedt 
Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Andrew Morton

lib: correct link to the original source for div64_u64

2012-06-28T09:51:39+00:00

Signed-off-by: Akinobu Mita 
Cc: Jiri Kosina 
Signed-off-by: Jiri Kosina

lib: reduce the use of module.h wherever possible

2012-03-07T20:04:04+00:00

For files only using THIS_MODULE and/or EXPORT_SYMBOL, map
them onto including export.h -- or if the file isn't even
using those, then just delete the include.  Fix up any implicit
include dependencies that were being masked by module.h along
the way.

Signed-off-by: Paul Gortmaker

div64_u64(): improve precision on 32bit platforms

2010-10-26T23:52:19+00:00

The current implementation of div64_u64 for 32bit systems returns an
approximately correct result when the divisor exceeds 32bits.  Since doing
64bit division using 32bit hardware is a long since solved problem we just
use one of the existing proven methods.

Additionally, add a div64_s64 function to correctly handle doing signed
64bit division.

Addresses https://bugzilla.redhat.com/show_bug.cgi?id=616105

Signed-off-by: Brian Behlendorf 
Signed-off-by: Oleg Nesterov 
Cc: Ben Woodard 
Cc: Jeremy Fitzhardinge 
Cc: Mark Grondona 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

add an inlined version of iter_div_u64_rem

2008-06-12T08:47:58+00:00

iter_div_u64_rem is used in the x86-64 vdso, which cannot call other
kernel code.  For this case, provide the always_inlined version,
__iter_div_u64_rem.

Signed-off-by: Jeremy Fitzhardinge 
Signed-off-by: Ingo Molnar

common implementation of iterative div/mod

2008-06-12T08:47:56+00:00

We have a few instances of the open-coded iterative div/mod loop, used
when we don't expcet the dividend to be much bigger than the divisor.
Unfortunately modern gcc's have the tendency to strength "reduce" this
into a full mod operation, which isn't necessarily any faster, and
even if it were, doesn't exist if gcc implements it in libgcc.

The workaround is to put a dummy asm statement in the loop to prevent
gcc from performing the transformation.

This patch creates a single implementation of this loop, and uses it
to replace the open-coded versions I know about.

Signed-off-by: Jeremy Fitzhardinge 
Cc: Andrew Morton 
Cc: john stultz 
Cc: Segher Boessenkool 
Cc: Christian Kujau 
Cc: Robert Hancock 
Signed-off-by: Ingo Molnar