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From:   Yuri Norov <ynorov@marvell.com>
To:     Andrew Morton <akpm@linux-foundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
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CC:     Yuri Norov <ynorov@marvell.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: [PATCH 0/4] rework bitmap_parselist
Thread-Topic: [PATCH 0/4] rework bitmap_parselist
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Date:   Sun, 23 Dec 2018 09:44:32 +0000
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bitmap_parselist evolved from a pretty simple idea for long and now lacks
for refactoring. It is not structured, has nested loops and a set of
opaque-named variables. All this leads to extremely hard understanding
of the code. Once during the optimization of it I missed a scenario which
leads to kernel hangup. Tetsuo Handa spotted this and found it simpler to
rewrite the code instead fixing it. (Though, that attempt had some flaws.)
https://lkml.org/lkml/2018/4/1/93

Things are more complicated than they may be because bitmap_parselist()
is part of user interface, and its behavior should not change.

In this patchset __bitmap_parselist() is split to a set of smaller
functions doing only one thing.

Yury Norov (4):
  bitmap_parselist: don't calculate length of the input string
  bitmap_parselist: move part of logic to helpers
  bitmap_parselist: rework input string parser
  test_bitmap: add testcases for bitmap_parselist

 lib/bitmap.c      | 294 ++++++++++++++++++++++++++++++----------------
 lib/test_bitmap.c |  18 ++-
 2 files changed, 208 insertions(+), 104 deletions(-)

--=20
2.17.1