linux-kernel - [RFC PATCH 05/49] qed: rework qed_rdma_bmap

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Message-Id: <20220210224933.379149-6-yury.norov@gmail.com>
Date:   Thu, 10 Feb 2022 14:48:49 -0800
From:   Yury Norov <yury.norov@...il.com>
To:     Yury Norov <yury.norov@...il.com>,
        Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michał Mirosław <mirq-linux@...e.qmqm.pl>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Peter Zijlstra <peterz@...radead.org>,
        David Laight <David.Laight@...lab.com>,
        Joe Perches <joe@...ches.com>, Dennis Zhou <dennis@...nel.org>,
        Emil Renner Berthing <kernel@...il.dk>,
        Nicholas Piggin <npiggin@...il.com>,
        Matti Vaittinen <matti.vaittinen@...rohmeurope.com>,
        Alexey Klimov <aklimov@...hat.com>,
        linux-kernel@...r.kernel.org, Ariel Elior <aelior@...vell.com>,
        Manish Chopra <manishc@...vell.com>,
        "David S. Miller" <davem@...emloft.net>,
        Jakub Kicinski <kuba@...nel.org>, netdev@...r.kernel.org
Subject: [RFC PATCH 05/49] qed: rework qed_rdma_bmap_free()

qed_rdma_bmap_free() is mostly an opencoded version of printk("%*pb").
Using %*pb format simplifies the code, and helps to avoid inefficient
usage of bitmap_weight().

While here, reorganize logic to avoid calculating bmap weight if check
is false.

Signed-off-by: Yury Norov <yury.norov@...il.com>
---

This is RFC because it changes lines printing format to bitmap %*pb. If
it hurts userspace, it's better to drop the patch.

 drivers/net/ethernet/qlogic/qed/qed_rdma.c | 45 +++++++---------------
 1 file changed, 14 insertions(+), 31 deletions(-)

diff --git a/drivers/net/ethernet/qlogic/qed/qed_rdma.c b/drivers/net/ethernet/qlogic/qed/qed_rdma.c
index 23b668de4640..f4c04af9d4dd 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_rdma.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_rdma.c
@@ -319,44 +319,27 @@ static int qed_rdma_alloc(struct qed_hwfn *p_hwfn)
 void qed_rdma_bmap_free(struct qed_hwfn *p_hwfn,
 			struct qed_bmap *bmap, bool check)
 {
-	int weight = bitmap_weight(bmap->bitmap, bmap->max_count);
-	int last_line = bmap->max_count / (64 * 8);
-	int last_item = last_line * 8 +
-	    DIV_ROUND_UP(bmap->max_count % (64 * 8), 64);
-	u64 *pmap = (u64 *)bmap->bitmap;
-	int line, item, offset;
-	u8 str_last_line[200] = { 0 };
-
-	if (!weight || !check)
+	unsigned int bit, weight, nbits;
+	unsigned long *b;
+
+	if (!check)
+		goto end;
+
+	weight = bitmap_weight(bmap->bitmap, bmap->max_count);
+	if (!weight)
 		goto end;
 
 	DP_NOTICE(p_hwfn,
 		  "%s bitmap not free - size=%d, weight=%d, 512 bits per line\n",
 		  bmap->name, bmap->max_count, weight);
 
-	/* 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))
+	for (bit = 0; bit < bmap->max_count; bit += 512) {
+		b =  bmap->bitmap + BITS_TO_LONGS(bit);
+		nbits = min(bmap->max_count - bit, 512);
+
+		if (!bitmap_empty(b, nbits))
 			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]);
-
-	/* print last unaligned non-zero line, if any */
-	if ((bmap->max_count % (64 * 8)) &&
-	    (bitmap_weight((unsigned long *)&pmap[item],
-			   bmap->max_count - item * 64))) {
-		offset = sprintf(str_last_line, "line 0x%04x: ", line);
-		for (; item < last_item; item++)
-			offset += sprintf(str_last_line + offset,
-					  "0x%016llx ", pmap[item]);
-		DP_NOTICE(p_hwfn, "%s\n", str_last_line);
+				  "line 0x%04x: %*pb\n", bit / 512, nbits, b);
 	}
 
 end:
-- 
2.32.0