[FAB-8570] Reduce log severity if existing block added

Gossip enqueues blocks into the payload buffer via different mechanisms:

    State transfer anti-entropy
    Pull
    Push

Whenever an attempt to add a block to the payload buffer which was
already added before by some other pathway - a warning is logged.

I think we should make that warning a debug, since it's not something
that users should be worried about.

Change-Id: Ia735473e33ddff3f8787c121f39a6d15e54baa04
Signed-off-by: yacovm <yacovm@il.ibm.com>

gossip/state/payloads_buffer.go

@@ -7,14 +7,12 @@ SPDX-License-Identifier: Apache-2.0
 package state
 
 import (
-	"strconv"
 	"sync"
 	"sync/atomic"
 
 	"github.com/hyperledger/fabric/gossip/util"
 	proto "github.com/hyperledger/fabric/protos/gossip"
 	"github.com/op/go-logging"
-	"github.com/pkg/errors"
 )
 
 // PayloadsBuffer is used to store payloads into which used to
@@ -23,7 +21,7 @@ import (
 // to signal whenever expected block has arrived.
 type PayloadsBuffer interface {
 	// Adds new block into the buffer
-	Push(payload *proto.Payload) error
+	Push(payload *proto.Payload)
 
 	// Returns next expected sequence number
 	Next() uint64
@@ -75,15 +73,15 @@ func (b *PayloadsBufferImpl) Ready() chan struct{} {
 // Push new payload into the buffer structure in case new arrived payload
 // sequence number is below the expected next block number payload will be
 // thrown away and error will be returned.
-func (b *PayloadsBufferImpl) Push(payload *proto.Payload) error {
+func (b *PayloadsBufferImpl) Push(payload *proto.Payload) {
 	b.mutex.Lock()
 	defer b.mutex.Unlock()
 
 	seqNum := payload.SeqNum
 
 	if seqNum < b.next || b.buf[seqNum] != nil {
-		return errors.Errorf("Payload with sequence number = %s has been already processed",
-			strconv.FormatUint(payload.SeqNum, 10))
+		logger.Debugf("Payload with sequence number = %d has been already processed", payload.SeqNum)
+		return
 	}
 
 	b.buf[seqNum] = payload
@@ -95,7 +93,6 @@ func (b *PayloadsBufferImpl) Push(payload *proto.Payload) error {
 			b.readyChan <- struct{}{}
 		}()
 	}
-	return nil
 }
 
 // Next function provides the number of the next expected block

gossip/state/payloads_buffer_test.go

@@ -122,8 +122,6 @@ func TestPayloadsBufferImpl_ConcurrentPush(t *testing.T) {
 	payload, err := randomPayloadWithSeqNum(nextSeqNum)
 	assert.NoError(t, err)
 
-	var errors []error
-
 	ready := int32(0)
 	readyWG := sync.WaitGroup{}
 	readyWG.Add(1)
@@ -136,26 +134,16 @@ func TestPayloadsBufferImpl_ConcurrentPush(t *testing.T) {
 
 	for i := 0; i < concurrency; i++ {
 		go func() {
+			buffer.Push(payload)
 			startWG.Wait()
-			errors = append(errors, buffer.Push(payload))
 			finishWG.Done()
 		}()
 	}
 	startWG.Done()
 	finishWG.Wait()
 
-	success := 0
-
-	// Only one push attempt expected to succeed
-	for _, err := range errors {
-		if err == nil {
-			success++
-		}
-	}
-
 	readyWG.Wait()
 	assert.Equal(t, int32(1), atomic.LoadInt32(&ready))
-	assert.Equal(t, 1, success)
 	// Buffer size has to be only one
 	assert.Equal(t, 1, buffer.Size())
 }

gossip/state/state.go

@@ -765,7 +765,8 @@ func (s *GossipStateProviderImpl) addPayload(payload *proto.Payload, blockingMod
 		time.Sleep(enqueueRetryInterval)
 	}
 
-	return s.payloads.Push(payload)
+	s.payloads.Push(payload)
+	return nil
 }
 
 func (s *GossipStateProviderImpl) commitBlock(block *common.Block, pvtData util.PvtDataCollections) error {