net_sched: act_gact: use a separate packet counters for gact_determ()

Second step for gact RCU operation : We want to get rid of the spinlock protecting gact operations. Stats (packets/bytes) will soon be per cpu. gact_determ() would not work without a central packet counter, so lets add it for this mode. Signed-off-by: Eric Dumazet <[email protected]> Cc: Alexei Starovoitov <[email protected]> Acked-by: Jamal Hadi Salim <[email protected]> Acked-by: John Fastabend <[email protected]> Signed-off-by: David S. Miller <[email protected]>
jledet · Jul 8, 2015 · cc6510a · cc6510a
1 parent cef5ecf
commit cc6510a
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Showing 2 changed files with 7 additions and 4 deletions.
diff --git a/include/net/tc_act/tc_gact.h b/include/net/tc_act/tc_gact.h
@@ -6,9 +6,10 @@
 struct tcf_gact {
 	struct tcf_common	common;
 #ifdef CONFIG_GACT_PROB
-        u16			tcfg_ptype;
-        u16			tcfg_pval;
-        int			tcfg_paction;
+	u16			tcfg_ptype;
+	u16			tcfg_pval;
+	int			tcfg_paction;
+	atomic_t		packets;
 #endif
 };
 #define to_gact(a) \

diff --git a/net/sched/act_gact.c b/net/sched/act_gact.c
@@ -36,8 +36,10 @@ static int gact_net_rand(struct tcf_gact *gact)
 
 static int gact_determ(struct tcf_gact *gact)
 {
+	u32 pack = atomic_inc_return(&gact->packets);
+
 	smp_rmb(); /* coupled with smp_wmb() in tcf_gact_init() */
-	if (gact->tcf_bstats.packets % gact->tcfg_pval)
+	if (pack % gact->tcfg_pval)
 		return gact->tcf_action;
 	return gact->tcfg_paction;
 }