rc80211-pid: simplify and fix shift_adjust

Simplify and fix rate_control_pid_shift_adjust(). A bug prevented correct
mapping of sorted rates, and readability was seriously flawed.

Signed-off-by: Stefano Brivio <stefano.brivio@polimi.it>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 18 deletions

diff --git a/net/mac80211/rc80211_pid_algo.c b/net/mac80211/rc80211_pid_algo.c
index b84e51480c84..3e26280d3142 100644
--- a/net/mac80211/rc80211_pid_algo.c
+++ b/net/mac80211/rc80211_pid_algo.c
@@ -74,29 +74,27 @@ static int rate_control_pid_shift_adjust(struct rc_pid_rateinfo *r,
 {
         int i, j, k, tmp;
 
-        if (cur + adj < 0)
-                return 0;
-        if (cur + adj >= l)
-                return l - 1;
+        j = r[cur].rev_index;
+        i = j + adj;
 
-        i = r[cur + adj].rev_index;
+        if (i < 0)
+                return r[0].index;
+        if (i >= l - 1)
+                return r[l - 1].index;
 
-        j = r[cur].rev_index;
+        tmp = i;
 
         if (adj < 0) {
-                        tmp = i;
-                        for (k = j; k >= i; k--)
-                                if (r[k].diff <= r[j].diff)
-                                        tmp = k;
-                        return r[tmp].index;
-        } else if (adj > 0) {
-                        tmp = i;
-                        for (k = i + 1; k + i < l; k++)
-                                if (r[k].diff <= r[i].diff)
-                                        tmp = k;
-                        return r[tmp].index;
+                for (k = j; k >= i; k--)
+                        if (r[k].diff <= r[j].diff)
+                                tmp = k;
+        } else {
+                for (k = i + 1; k + i < l; k++)
+                        if (r[k].diff <= r[i].diff)
+                                tmp = k;
         }
-        return cur + adj;
+
+        return r[tmp].index;
 }
 
 static void rate_control_pid_adjust_rate(struct ieee80211_local *local,