set flow port to 0 in bpfmap to avoid duplicate labels

alibaba · Apr 7, 2024 · 7fc62d6 · 7fc62d6
1 parent dfcfff1
commit 7fc62d6
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Showing 4 changed files with 28 additions and 9 deletions.
diff --git a/bpf/flow.c b/bpf/flow.c
@@ -6,6 +6,8 @@
 
 #define TC_ACT_OK 0
 
+volatile const bool enable_flow_port = 0;
+
 //todo aggregate all flow based metrics in one map to save memory.
 struct flow_metrics {
     u64 packets;
@@ -24,7 +26,7 @@ struct {
 
 static inline int __do_flow(struct __sk_buff *skb){
     struct flow_tuple_4 tuple = {0};
-    if(set_flow_tuple4(skb, &tuple) < 0){
+    if(set_flow_tuple4(skb, &tuple, enable_flow_port) < 0){
         goto out;
     }
 

diff --git a/bpf/headers/inspector.h b/bpf/headers/inspector.h
@@ -111,7 +111,7 @@ static __always_inline u32 get_netns(struct sk_buff *skb) {
   return netns;
 }
 
-static __always_inline int set_flow_tuple4(struct __sk_buff *skb, struct flow_tuple_4 *tuple){
+static __always_inline int set_flow_tuple4(struct __sk_buff *skb, struct flow_tuple_4 *tuple, bool port){
 	void *data = (void *)(long)skb->data;
 	struct ethhdr *eth = data;
 	void *data_end = (void *)(long)skb->data_end;
@@ -130,6 +130,9 @@ static __always_inline int set_flow_tuple4(struct __sk_buff *skb, struct flow_tu
         tuple->src = iph->saddr;
         tuple->dst = iph->daddr;
         tuple->proto = iph->protocol;
+        if (!port){
+            return 0;
+        }
 
         l4_off = sizeof(*eth) + iph->ihl * 4;
 

diff --git a/bpf/packetloss.c b/bpf/packetloss.c
@@ -23,7 +23,7 @@ struct insp_pl_event_t {
 };
 
 const struct insp_pl_event_t *unused_insp_pl_event_t __attribute__((unused));
-const volatile u8 enable_packetloss_stack = 0;
+const volatile bool enable_packetloss_stack = 0;
 
 struct {
 	__uint(type, BPF_MAP_TYPE_STACK_TRACE);

diff --git a/pkg/exporter/probe/flow/flow.go b/pkg/exporter/probe/flow/flow.go
@@ -299,16 +299,30 @@ func (p *metricsProbe) loadBPF() error {
 		return fmt.Errorf("remove limit failed: %s", err.Error())
 	}
 
-	opts := ebpf.CollectionOptions{}
+	spec, err := loadBpf()
+	if err != nil {
+		return fmt.Errorf("failed loading bpf: %w", err)
+	}
+
+	if p.enablePort {
+		m := map[string]interface{}{
+			"enable_flow_port": uint8(1),
+		}
+		if err := spec.RewriteConstants(m); err != nil {
+			return fmt.Errorf("failed rewrite constants: %w", err)
+		}
+	}
 
-	opts.Programs = ebpf.ProgramOptions{
-		KernelTypes: bpfutil.LoadBTFSpecOrNil(),
+	opts := ebpf.CollectionOptions{
+		Programs: ebpf.ProgramOptions{
+			KernelTypes: bpfutil.LoadBTFSpecOrNil(),
+		},
 	}
 
-	// Load pre-compiled programs and maps into the kernel.
-	if err := loadBpfObjects(&p.bpfObjs, &opts); err != nil {
-		return fmt.Errorf("failed loading objects: %w", err)
+	if err := spec.LoadAndAssign(&p.bpfObjs, &opts); err != nil {
+		return fmt.Errorf("loading objects: %s", err.Error())
 	}
+
 	return nil
 }