sch_red: generalize accurate MAX_P support to RED/GRED/CHOKE

[linux-2.6-microblaze.git] / include / net / red.h

diff --git a/include/net/red.h b/include/net/red.h
index 24606b2..ef715a1 100644 (file)
--- a/include/net/red.h
+++ b/include/net/red.h
@@ -155,9 +155,10 @@ static inline u32 red_maxp(u8 Plog)
 
 static inline void red_set_parms(struct red_parms *p,
                                 u32 qth_min, u32 qth_max, u8 Wlog, u8 Plog,
-                                u8 Scell_log, u8 *stab)
+                                u8 Scell_log, u8 *stab, u32 max_P)
 {
        int delta = qth_max - qth_min;
+       u32 max_p_delta;
 
        /* Reset average queue length, the value is strictly bound
         * to the parameters below, reseting hurts a bit but leaving
@@ -173,10 +174,14 @@ static inline void red_set_parms(struct red_parms *p,
        if (delta < 0)
                delta = 1;
        p->qth_delta    = delta;
-       p->max_P        = red_maxp(Plog);
-       p->max_P        *= delta; /* max_P = (qth_max-qth_min)/2^Plog */
-
-       p->max_P_reciprocal  = reciprocal_value(p->max_P / delta);
+       if (!max_P) {
+               max_P = red_maxp(Plog);
+               max_P *= delta; /* max_P = (qth_max - qth_min)/2^Plog */
+       }
+       p->max_P = max_P;
+       max_p_delta = max_P / delta;
+       max_p_delta = max(max_p_delta, 1U);
+       p->max_P_reciprocal  = reciprocal_value(max_p_delta);
 
        /* RED Adaptative target :
         * [min_th + 0.4*(min_th - max_th),
@@ -380,6 +385,7 @@ static inline void red_adaptative_algo(struct red_parms *p)
                p->max_P = (p->max_P/10)*9; /* maxp = maxp * Beta */
 
        max_p_delta = DIV_ROUND_CLOSEST(p->max_P, p->qth_delta);
+       max_p_delta = max(max_p_delta, 1U);
        p->max_P_reciprocal = reciprocal_value(max_p_delta);
 }
 #endif