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

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?

The printing part may be refactored although to use %pb" format,
similarly to the snippet below
(not tested).

Thanks,
Yury

diff --git a/drivers/net/ethernet/qlogic/qed/qed_rdma.c

b/drivers/net/ethernet/qlogic/qed/qed_rdma.c
index 23b668de4640..72505517ced1 100644

--- a/drivers/net/ethernet/qlogic/qed/qed_rdma.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_rdma.c

@@ -336,17 +336,8 @@ void qed_rdma_bmap_free(struct qed_hwfn *p_hwfn,

        /* print aligned non-zero lines, if any */
        for (item = 0, line = 0; line < last_line; line++, item += 8)
-               if (bitmap_weight((unsigned long *)&pmap[item], 64 * 8))
-                       DP_NOTICE(p_hwfn,
-                                 "line 0x%04x: 0x%016llx 0x%016llx

0x%016llx 0x%016llx 0x%016llx 0x%016llx 0x%016llx 0x%016llx\n",
-                                 line,
-                                 pmap[item],
-                                 pmap[item + 1],
-                                 pmap[item + 2],
-                                 pmap[item + 3],
-                                 pmap[item + 4],
-                                 pmap[item + 5],
-                                 pmap[item + 6], pmap[item + 7]);
+               if (bitmap_weight(bmap->bitmap, 64 * 8))
+                       DP_NOTICE(p_hwfn, "line 0x%04x: %512pb\n",
line, bmap->bitmap);

        /* print last unaligned non-zero line, if any */
        if ((bmap->max_count % (64 * 8)) &&