From: Yury Norov

Sent: 25 January 2022 21:10
On Mon, Jan 24, 2022 at 4:29 AM Andy Shevchenko
[off-list ref] wrote:

quoted

On Sun, Jan 23, 2022 at 10:38:41AM -0800, Yury Norov wrote:

quoted

qlogic/qed code calls bitmap_weight() to check if any bit of a given
bitmap is set. It's better to use bitmap_empty() in that case because
bitmap_empty() stops traversing the bitmap as soon as it finds first
set bit, while bitmap_weight() counts all bits unconditionally.

quoted

-             if (bitmap_weight((unsigned long *)&pmap[item], 64 * 8))
+             if (!bitmap_empty((unsigned long *)&pmap[item], 64 * 8))

quoted

-         (bitmap_weight((unsigned long *)&pmap[item],
+         (!bitmap_empty((unsigned long *)&pmap[item],

Side note, these castings reminds me previous discussion and I'm wondering
if you have this kind of potentially problematic places in your TODO as
subject to fix.

In the discussion you mentioned above, the u32* was cast to u64*,
which is wrong. The code
here is safe because in the worst case, it casts u64* to u32*. This
would be OK wrt
 -Werror=array-bounds.

The function itself looks like doing this unsigned long <-> u64
conversions just for printing
purpose. I'm not a qlogic expert, so let's wait what people say?

It'll be wrong on BE systems.
You just can't cast the argument it has to be long[].

	David

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