Re: [PATCH v5 2/2] lib/test-string_helpers.c: add string_get_size() tests

From: Rasmus Villemoes
Date: Wed Oct 21 2015 - 06:19:23 EST


On Thu, Sep 17 2015, Vitaly Kuznetsov <vkuznets@xxxxxxxxxx> wrote:

> +
> +static __init void test_string_get_size(void)
> +{
> + test_string_get_size_one(16384, 512, STRING_UNITS_2, "8.00 MiB");
> + test_string_get_size_one(8192, 4096, STRING_UNITS_10, "32.7 MB");

This is a little late, but I just noticed that string_get_size with
STRING_UNITS_10, block size >= 1024 and sufficiently large size seems to
be broken. Yes, 32.7 MB is what it produces, but is it what it should
give? 8192*4096 = 33554432, so I'd expect "33.5 MB". It does give that
when we pass size=65536 and block_size=512; a combination with the same
product.

I think the problem is that the remainder coming out of the while
(blk_size >= divisor[units]) loop is dropped on the floor in the
subsequent size > exp case - but I'm too lazy right now to figure out how
to fix it.

Rasmus
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/