Do not trigger prefix_limit_trigger_ from BgpPeer constructor

Instead, trigger only when configuration changes are processed.
Also, trigger prefix_limit_trigger_ through a virtualized method so that
BgpMockPeers can override and skip the actual task trigger process.

Change-Id: I16befdad1cf43ef467da8dfc7d2994ddc005ca3a
Closes-Bug: 1706792

src/bgp/bgp_peer.cc

@@ -786,7 +786,6 @@ bool BgpPeer::ProcessFamilyAttributesConfig(const BgpNeighborConfig *config) {
     STLDeleteValues(&family_attributes_list_);
     family_attributes_list_ = family_attributes_list;
     configured_families_ = config->GetAddressFamilies();
-    prefix_limit_trigger_.Set();
     return (ret != 0);
 }
 
@@ -798,6 +797,10 @@ void BgpPeer::ProcessEndpointConfig(const BgpNeighborConfig *config) {
     }
 }
 
+void BgpPeer::TriggerPrefixLimitCheck() const {
+    prefix_limit_trigger_.Set();
+}
+
 void BgpPeer::ConfigUpdate(const BgpNeighborConfig *config) {
     if (IsDeleted())
         return;
@@ -911,6 +914,8 @@ void BgpPeer::ConfigUpdate(const BgpNeighborConfig *config) {
     if (ProcessFamilyAttributesConfig(config)) {
         peer_info.set_configured_families(configured_families_);
         clear_session = true;
+    } else {
+        TriggerPrefixLimitCheck();
     }
 
     // Note that the state machine would have been stopped via SetAdminDown
@@ -1740,7 +1745,7 @@ void BgpPeer::UpdatePrimaryPathCount(int count, Address::Family family) const {
     if (family_attributes_list_[family])
         limit = family_attributes_list_[family]->prefix_limit;
     if (limit && family_primary_path_count_[family] > limit)
-        prefix_limit_trigger_.Set();
+        TriggerPrefixLimitCheck();
 }
 
 void BgpPeer::EndOfRibTimerErrorHandler(string error_name,

src/bgp/bgp_peer.h

@@ -405,6 +405,7 @@ class BgpPeer : public IPeer {
     std::string BytesToHexString(const u_int8_t *msg, size_t size);
     virtual uint32_t GetOutputQueueDepth(Address::Family family) const;
     virtual time_t GetRTargetTableLastUpdatedTimeStamp() const;
+    virtual void TriggerPrefixLimitCheck() const;
 
     static const std::vector<Address::Family> supported_families_;
     BgpServer *server_;

src/bgp/test/bgp_membership_test.cc

@@ -55,6 +55,7 @@ class BgpTestPeer : public BgpPeer {
     }
     uint64_t path_cb_count() const { return path_cb_count_; }
     virtual bool IsInGRTimerWaitState() const { return false; }
+    void TriggerPrefixLimitCheck() const { }
 
 private:
     RibExportPolicy policy_;

src/bgp/test/bgp_msg_builder_test.cc

@@ -30,6 +30,7 @@ class BgpPeerMock : public BgpPeer {
     bool IsReady() const { return true; }
     bool notification() const { return notification_; }
     void set_notification(bool notification) { notification_ = notification; }
+    void TriggerPrefixLimitCheck() const { }
 private:
     bool notification_;
 };

src/bgp/test/bgp_peer_test.cc

@@ -64,6 +64,7 @@ class BgpPeerMock : public BgpPeer {
         is_ready_ = is_ready;
     }
 
+    void TriggerPrefixLimitCheck() const { }
     virtual void StartKeepaliveTimerUnlocked() { }
     virtual time_t GetEorSendTimerElapsedTime() const { return elapsed_; }
     virtual bool IsReady() const { return is_ready_; }

src/bgp/test/bgp_session_test.cc

@@ -39,6 +39,7 @@ class BgpPeerMock : public BgpPeer {
     vector<int>::const_iterator end() const {
         return sizes.end();
     }
+    void TriggerPrefixLimitCheck() const { }
 
 private:
     vector<int> sizes;

src/bgp/test/bgp_update_rx_test.cc

@@ -28,6 +28,7 @@ class BgpPeerMock : public BgpPeer {
     }
 
     bool IsReady() const { return true; }
+    void TriggerPrefixLimitCheck() const { }
 };
 
 class BgpUpdateRxTest : public ::testing::Test {