sch: make htb_rate_cfg and functions around that generic

As it is going to be used in tbf as well, push these to generic code.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 46 insertions, 56 deletions

diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index 5d81a4478514..ffad48109a22 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -25,6 +25,7 @@
 #include <linux/rcupdate.h>
 #include <linux/list.h>
 #include <linux/slab.h>
+#include <net/sch_generic.h>
 #include <net/pkt_sched.h>
 #include <net/dst.h>
 
@@ -896,3 +897,39 @@ void dev_shutdown(struct net_device *dev)
 
         WARN_ON(timer_pending(&dev->watchdog_timer));
 }
+
+void psched_ratecfg_precompute(struct psched_ratecfg *r, u32 rate)
+{
+        u64 factor;
+        u64 mult;
+        int shift;
+
+        r->rate_bps = rate << 3;
+        r->shift = 0;
+        r->mult = 1;
+        /*
+         * Calibrate mult, shift so that token counting is accurate
+         * for smallest packet size (64 bytes).  Token (time in ns) is
+         * computed as (bytes * 8) * NSEC_PER_SEC / rate_bps.  It will
+         * work as long as the smallest packet transfer time can be
+         * accurately represented in nanosec.
+         */
+        if (r->rate_bps > 0) {
+                /*
+                 * Higher shift gives better accuracy.  Find the largest
+                 * shift such that mult fits in 32 bits.
+                 */
+                for (shift = 0; shift < 16; shift++) {
+                        r->shift = shift;
+                        factor = 8LLU * NSEC_PER_SEC * (1 << r->shift);
+                        mult = div64_u64(factor, r->rate_bps);
+                        if (mult > UINT_MAX)
+                                break;
+                }
+
+                r->shift = shift - 1;
+                factor = 8LLU * NSEC_PER_SEC * (1 << r->shift);
+                r->mult = div64_u64(factor, r->rate_bps);
+        }
+}
+EXPORT_SYMBOL(psched_ratecfg_precompute);
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 2b225446b3de..03c2692ca01e 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -38,6 +38,7 @@
 #include <linux/workqueue.h>
 #include <linux/slab.h>
 #include <net/netlink.h>
+#include <net/sch_generic.h>
 #include <net/pkt_sched.h>
 
 /* HTB algorithm.
@@ -71,12 +72,6 @@ enum htb_cmode {
         HTB_CAN_SEND            /* class can send */
 };
 
-struct htb_rate_cfg {
-        u64 rate_bps;
-        u32 mult;
-        u32 shift;
-};
-
 /* interior & leaf nodes; props specific to leaves are marked L: */
 struct htb_class {
         struct Qdisc_class_common common;
@@ -124,8 +119,8 @@ struct htb_class {
         int filter_cnt;
 
         /* token bucket parameters */
-        struct htb_rate_cfg rate;
-        struct htb_rate_cfg ceil;
+        struct psched_ratecfg rate;
+        struct psched_ratecfg ceil;
         s64 buffer, cbuffer;    /* token bucket depth/rate */
         psched_tdiff_t mbuffer; /* max wait time */
         s64 tokens, ctokens;    /* current number of tokens */
@@ -168,45 +163,6 @@ struct htb_sched {
         struct work_struct work;
 };
 
-static u64 l2t_ns(struct htb_rate_cfg *r, unsigned int len)
-{
-        return ((u64)len * r->mult) >> r->shift;
-}
-
-static void htb_precompute_ratedata(struct htb_rate_cfg *r)
-{
-        u64 factor;
-        u64 mult;
-        int shift;
-
-        r->shift = 0;
-        r->mult = 1;
-        /*
-         * Calibrate mult, shift so that token counting is accurate
-         * for smallest packet size (64 bytes).  Token (time in ns) is
-         * computed as (bytes * 8) * NSEC_PER_SEC / rate_bps.  It will
-         * work as long as the smallest packet transfer time can be
-         * accurately represented in nanosec.
-         */
-        if (r->rate_bps > 0) {
-                /*
-                 * Higher shift gives better accuracy.  Find the largest
-                 * shift such that mult fits in 32 bits.
-                 */
-                for (shift = 0; shift < 16; shift++) {
-                        r->shift = shift;
-                        factor = 8LLU * NSEC_PER_SEC * (1 << r->shift);
-                        mult = div64_u64(factor, r->rate_bps);
-                        if (mult > UINT_MAX)
-                                break;
-                }
-
-                r->shift = shift - 1;
-                factor = 8LLU * NSEC_PER_SEC * (1 << r->shift);
-                r->mult = div64_u64(factor, r->rate_bps);
-        }
-}
-
 /* find class in global hash table using given handle */
 static inline struct htb_class *htb_find(u32 handle, struct Qdisc *sch)
 {
@@ -632,7 +588,7 @@ static inline void htb_accnt_tokens(struct htb_class *cl, int bytes, s64 diff)
 
         if (toks > cl->buffer)
                 toks = cl->buffer;
-        toks -= (s64) l2t_ns(&cl->rate, bytes);
+        toks -= (s64) psched_l2t_ns(&cl->rate, bytes);
         if (toks <= -cl->mbuffer)
                 toks = 1 - cl->mbuffer;
 
@@ -645,7 +601,7 @@ static inline void htb_accnt_ctokens(struct htb_class *cl, int bytes, s64 diff)
 
         if (toks > cl->cbuffer)
                 toks = cl->cbuffer;
-        toks -= (s64) l2t_ns(&cl->ceil, bytes);
+        toks -= (s64) psched_l2t_ns(&cl->ceil, bytes);
         if (toks <= -cl->mbuffer)
                 toks = 1 - cl->mbuffer;
 
@@ -1134,9 +1090,9 @@ static int htb_dump_class(struct Qdisc *sch, unsigned long arg,
 
         memset(&opt, 0, sizeof(opt));
 
-        opt.rate.rate = cl->rate.rate_bps >> 3;
+        opt.rate.rate = psched_ratecfg_getrate(&cl->rate);
         opt.buffer = PSCHED_NS2TICKS(cl->buffer);
-        opt.ceil.rate = cl->ceil.rate_bps >> 3;
+        opt.ceil.rate = psched_ratecfg_getrate(&cl->ceil);
         opt.cbuffer = PSCHED_NS2TICKS(cl->cbuffer);
         opt.quantum = cl->quantum;
         opt.prio = cl->prio;
@@ -1503,11 +1459,8 @@ static int htb_change_class(struct Qdisc *sch, u32 classid,
                         cl->prio = TC_HTB_NUMPRIO - 1;
         }
 
-        cl->rate.rate_bps = (u64)hopt->rate.rate << 3;
-        cl->ceil.rate_bps = (u64)hopt->ceil.rate << 3;
-
-        htb_precompute_ratedata(&cl->rate);
-        htb_precompute_ratedata(&cl->ceil);
+        psched_ratecfg_precompute(&cl->rate, hopt->rate.rate);
+        psched_ratecfg_precompute(&cl->ceil, hopt->ceil.rate);
 
         cl->buffer = PSCHED_TICKS2NS(hopt->buffer);
         cl->cbuffer = PSCHED_TICKS2NS(hopt->buffer);