From: Lars Ellenberg <lars.ellenb...@linbit.com>
Suggested by Akinobu Mita <akinobu.m...@gmail.com>
Signed-off-by: Philipp Reisner <philipp.reis...@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenb...@linbit.com>
---
drivers/block/drbd/drbd_bitmap.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/block/drbd/drbd_bitmap.c b/drivers/block/drbd/drbd_bitmap.c
index 227deb0..c09c571 100644
--- a/drivers/block/drbd/drbd_bitmap.c
+++ b/drivers/block/drbd/drbd_bitmap.c
@@ -24,7 +24,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-#include <linux/bitops.h>
+#include <linux/bitmap.h>
#include <linux/vmalloc.h>
#include <linux/string.h>
#include <linux/drbd.h>
@@ -565,21 +565,19 @@ static unsigned long bm_count_bits(struct drbd_bitmap *b)
unsigned long *p_addr;
unsigned long bits = 0;
unsigned long mask = (1UL << (b->bm_bits & BITS_PER_LONG_MASK)) -1;
- int idx, i, last_word;
+ int idx, last_word;
/* all but last page */
for (idx = 0; idx < b->bm_number_of_pages - 1; idx++) {
p_addr = __bm_map_pidx(b, idx);
- for (i = 0; i < LWPP; i++)
- bits += hweight_long(p_addr[i]);
+ bits += bitmap_weight(p_addr, BITS_PER_PAGE);
__bm_unmap(p_addr);
cond_resched();
}
/* last (or only) page */
last_word = ((b->bm_bits - 1) & BITS_PER_PAGE_MASK) >> LN2_BPL;
p_addr = __bm_map_pidx(b, idx);
- for (i = 0; i < last_word; i++)
- bits += hweight_long(p_addr[i]);
+ bits += bitmap_weight(p_addr, last_word * BITS_PER_LONG);
p_addr[last_word] &= cpu_to_lel(mask);
bits += hweight_long(p_addr[last_word]);
/* 32bit arch, may have an unused padding long */
@@ -1434,6 +1432,9 @@ static inline void
bm_set_full_words_within_one_page(struct drbd_bitmap *b,
int bits;
int changed = 0;
unsigned long *paddr = kmap_atomic(b->bm_pages[page_nr]);
+
+ /* I think it is more cache line friendly to hweight_long then set to
~0UL,
+ * than to first bitmap_weight() all words, then bitmap_fill() all
words */
for (i = first_word; i < last_word; i++) {
bits = hweight_long(paddr[i]);
paddr[i] = ~0UL;
@@ -1643,8 +1644,7 @@ int drbd_bm_e_weight(struct drbd_device *device, unsigned
long enr)
int n = e-s;
p_addr = bm_map_pidx(b, bm_word_to_page_idx(b, s));
bm = p_addr + MLPP(s);
- while (n--)
- count += hweight_long(*bm++);
+ count += bitmap_weight(bm, n * BITS_PER_LONG);
bm_unmap(p_addr);
} else {
drbd_err(device, "start offset (%d) too large in
drbd_bm_e_weight\n", s);
--
1.9.1
--
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