Re: [PATCH] ath9k: Use swap() instead of open coding it

Re: [PATCH] ath9k: Use swap() instead of open coding it

[Toke Høiland-Jørgensen]

"Tan Zhongjun" <tanzhongjun@coolpad.com> writes:

> Use swap() instead of open coding it
>
> Signed-off-by: Tan Zhongjun <tanzhongjun@coolpad.com>

Please don't send HTML email, the mailing lists will drop that. Also, an
identical patch was submitted back in February and an issue was pointed
out which your patch also suffers from:

https://lore.kernel.org/r/a2400dd73f6ea8672bb6e50124cc3041c0c43d6d.1644838854.git.yang.guang5@zte.com.cn

-Toke

Re: [PATCH] ath9k: Use swap() instead of open coding it

[Joe Perches]

On Mon, 2022-07-04 at 16:55 +0200, Toke Høiland-Jørgensen wrote:
> "Tan Zhongjun" <tanzhongjun@coolpad.com> writes:
> 
> > Use swap() instead of open coding it
> > 
> > Signed-off-by: Tan Zhongjun <tanzhongjun@coolpad.com>
> 
> Please don't send HTML email, the mailing lists will drop that. Also, an
> identical patch was submitted back in February and an issue was pointed
> out which your patch also suffers from:
> 
> https://lore.kernel.org/r/a2400dd73f6ea8672bb6e50124cc3041c0c43d6d.1644838854.git.yang.guang5@zte.com.cn

Perhaps instead use sort instead of a bubble sort.

Something like:
---
 drivers/net/wireless/ath/ath9k/calib.c | 35 ++++++++++++++++++----------------
 1 file changed, 19 insertions(+), 16 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index 0422a33395b77..4e298925049e8 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -17,29 +17,32 @@
 #include "hw.h"
 #include "hw-ops.h"
 #include <linux/export.h>
+#include <linux/sort.h>
 
 /* Common calibration code */
 
+static int cmp_int16_t(const void *a, const void *b)
+{
+	int16_t a1 = *(int16_t *)a;
+	int16_t b1 = *(int16_t *)b;
+
+	if (a1 < b1)
+		return -1;
+	if (a1 > b1)
+		return 1;
+	return 0;
+}
 
 static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer)
 {
 	int16_t nfval;
-	int16_t sort[ATH9K_NF_CAL_HIST_MAX];
-	int i, j;
-
-	for (i = 0; i < ATH9K_NF_CAL_HIST_MAX; i++)
-		sort[i] = nfCalBuffer[i];
-
-	for (i = 0; i < ATH9K_NF_CAL_HIST_MAX - 1; i++) {
-		for (j = 1; j < ATH9K_NF_CAL_HIST_MAX - i; j++) {
-			if (sort[j] > sort[j - 1]) {
-				nfval = sort[j];
-				sort[j] = sort[j - 1];
-				sort[j - 1] = nfval;
-			}
-		}
-	}
-	nfval = sort[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1];
+	int16_t sorted[ATH9K_NF_CAL_HIST_MAX];
+
+	memcpy(sorted, nfCalBuffer, sizeof(int16_t) * ATH9K_NF_CAL_HIST_MAX);
+
+	sort(sorted, ARRAY_SIZE(sorted), sizeof(int16_t), cmp_int16_t, NULL);
+
+	nfval = sorted[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1];
 
 	return nfval;
 }