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-rw-r--r--drivers/staging/batman-adv/TODO1
-rw-r--r--drivers/staging/batman-adv/bitarray.c15
-rw-r--r--drivers/staging/batman-adv/bitarray.h3
3 files changed, 7 insertions, 12 deletions
diff --git a/drivers/staging/batman-adv/TODO b/drivers/staging/batman-adv/TODO
index 9c5aea20be15..d8bf845b9bba 100644
--- a/drivers/staging/batman-adv/TODO
+++ b/drivers/staging/batman-adv/TODO
@@ -1,4 +1,3 @@
- * Use hweight* for hamming weight calculation
* Save/cache packets direktly as skb instead of using a normal memory region
and copying it in a skb using send_raw_packet and similar functions
* Request a new review
diff --git a/drivers/staging/batman-adv/bitarray.c b/drivers/staging/batman-adv/bitarray.c
index dd4193c99d4e..9dbaf1e8e6a5 100644
--- a/drivers/staging/batman-adv/bitarray.c
+++ b/drivers/staging/batman-adv/bitarray.c
@@ -22,6 +22,8 @@
#include "main.h"
#include "bitarray.h"
+#include <linux/bitops.h>
+
/* returns true if the corresponding bit in the given seq_bits indicates true
* and curr_seqno is within range of last_seqno */
uint8_t get_bit_status(TYPE_OF_WORD *seq_bits, uint32_t last_seqno,
@@ -187,21 +189,14 @@ char bit_get_packet(TYPE_OF_WORD *seq_bits, int32_t seq_num_diff,
}
/* count the hamming weight, how many good packets did we receive? just count
- * the 1's. The inner loop uses the Kernighan algorithm, see
- * http://graphics.stanford.edu/~seander/bithacks.html#CountBitsSetKernighan
+ * the 1's.
*/
int bit_packet_count(TYPE_OF_WORD *seq_bits)
{
int i, hamming = 0;
- TYPE_OF_WORD word;
- for (i = 0; i < NUM_WORDS; i++) {
- word = seq_bits[i];
+ for (i = 0; i < NUM_WORDS; i++)
+ hamming += hweight_long(seq_bits[i]);
- while (word) {
- word &= word-1;
- hamming++;
- }
- }
return hamming;
}
diff --git a/drivers/staging/batman-adv/bitarray.h b/drivers/staging/batman-adv/bitarray.h
index 01897d6962d0..28479ea7f7f7 100644
--- a/drivers/staging/batman-adv/bitarray.h
+++ b/drivers/staging/batman-adv/bitarray.h
@@ -22,7 +22,8 @@
#ifndef _NET_BATMAN_ADV_BITARRAY_H_
#define _NET_BATMAN_ADV_BITARRAY_H_
-/* you should choose something big, if you don't want to waste cpu */
+/* you should choose something big, if you don't want to waste cpu
+ * and keep the type in sync with bit_packet_count */
#define TYPE_OF_WORD unsigned long
#define WORD_BIT_SIZE (sizeof(TYPE_OF_WORD) * 8)