Commit 0746a0bc authored Nov 17, 2017 by Alexey Dobriyan Committed by Linus Torvalds Nov 17, 2017

proc: use do-while in name_to_int()

Gcc doesn't know that "len" is guaranteed to be >=1 by dcache and
generates standard while-loop prologue duplicating loop condition.

	add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-27 (-27)
	function                                     old     new   delta
	name_to_int                                  104      77     -27

Link: http://lkml.kernel.org/r/20170912195213.GB17730@avx2


Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 3ee2a199

fs/proc/util.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -8,7 +8,7 @@ unsigned name_to_int(const struct qstr *qstr)

		if (len > 1 && *name == '0')
		goto out;
		while (len-- > 0) {
		do {
		unsigned c = *name++ - '0';
		if (c > 9)
		goto out;
		@@ -16,7 +16,7 @@ unsigned name_to_int(const struct qstr *qstr)
		goto out;
		n *= 10;
		n += c;
		}
		} while (--len > 0);
		return n;
		out:
		return ~0U;

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