Re: patch: annoying u32 double listing

[Patrick McHardy <kaber@xxxxxxxxx>]

jamal wrote:

> bug is around since 2.1.x; never cared about chasing it until now
> because it is affecting someone i know.
> Dave, please apply. I will prepare a 2.4.x version.
The patch is wrong. The "divisor"-lines are missing in the output with
your patch and it only hides the real error. ->walk is supposed to walk
all filters of the given priority/protocol, but u32 walks all filters.
This patch fixes it. Output with new patch:

filter protocol ip pref 6 u32
filter protocol ip pref 6 u32 fh 800: ht divisor 1
filter protocol ip pref 6 u32 fh 800::800 order 2048 key ht 800 bkt 0 
flowid 1:16  (rule hit 0 success 0)
 match 0a0000d2/ffffffff at 12 (success 0 )
filter protocol ip pref 7 u32
filter protocol ip pref 7 u32 fh 801: ht divisor 1
filter protocol ip pref 7 u32 fh 801::800 order 2048 key ht 801 bkt 0 
flowid 1:15  (rule hit 0 success 0)
 match 0a000090/ffffffff at 12 (success 0 )

Signed-off-by: Patrick McHardy <kaber@xxxxxxxxx>

BTW: u32_walk seems to have another bug, it uses tcf_walker->count and
tcf_walker->skip for skipping over both hnodes and knodes and doesn't
skip hnodes properly at all. I'll have a look at this now.

Regards
Patrick

> AFTER FIX: 
> ---------
>
> root@jdev:/usr/src# tc -s filter show parent ffff: dev eth0
> filter protocol ip pref 6 u32
> filter protocol ip pref 6 u32 fh 800::800 order 2048 key ht 800 bkt 0
> flowid 1:16  
>  match 0a0000d2/ffffffff at 12 
>  filter protocol ip pref 7 u32
>  filter protocol ip pref 7 u32 fh 801::800 order 2048 key ht 801 bkt 0
> flowid 1:15  
>    match 0a000090/ffffffff at 12 
>
>  
===== net/sched/cls_u32.c 1.25 vs edited =====
--- 1.25/net/sched/cls_u32.c    2005-01-11 20:25:16 +01:00
+++ edited/net/sched/cls_u32.c  2005-02-06 22:20:33 +01:00
@@ -91,6 +91,7 @@
 {
        struct tc_u_hnode       *next;
        u32                     handle;
+       u32                     prio;
        struct tc_u_common      *tp_c;
        int                     refcnt;
        unsigned                divisor;
@@ -323,6 +324,7 @@
        root_ht->divisor = 0;
        root_ht->refcnt++;
        root_ht->handle = tp_c ? gen_new_htid(tp_c) : 0x80000000;
+       root_ht->prio = tp->prio;
 
        if (tp_c == NULL) {
                tp_c = kmalloc(sizeof(*tp_c), GFP_KERNEL);
@@ -703,6 +705,8 @@
                return;
 
        for (ht = tp_c->hlist; ht; ht = ht->next) {
+               if (ht->prio != tp->prio)
+                       continue;
                if (arg->count >= arg->skip) {
                        if (arg->fn(tp, (unsigned long)ht, arg) < 0) {
                                arg->stop = 1;