Relying on the sign (after casting to int) of the difference of two
quantities for comparison is usually wrong. For example, should a-b
turn out to be 2^31, the return value of cmp(a,b) is -2^31; but that
would also be the return value from cmp(b, a). So a compares less than
b and b compares less than a. One can also easily find three values
a,b,c such that a compares less than b, b compares less than c, but a
does not compare less than c.
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>