hold granular locking for multi-pool PutObject() (#20434)

- PutObject() for multi-pooled was holding large
  region locks, which was not necessary. This affects
  almost all slowpoke clients and lengthy uploads.

- Re-arrange locks for CompleteMultipart, PutObject
  to be close to rename()

cmd/erasure-multipart.go

@@ -455,8 +455,11 @@ func (er erasureObjects) newMultipartUpload(ctx context.Context, bucket string,
 	}
 	fi.DataDir = mustGetUUID()
 
-	if userDefined[ReplicationSsecChecksumHeader] != "" {
+	if ckSum := userDefined[ReplicationSsecChecksumHeader]; ckSum != "" {
-		fi.Checksum, _ = base64.StdEncoding.DecodeString(userDefined[ReplicationSsecChecksumHeader])
+		v, err := base64.StdEncoding.DecodeString(ckSum)
+		if err == nil {
+			fi.Checksum = v
+		}
 		delete(userDefined, ReplicationSsecChecksumHeader)
 	}
 
@@ -1331,16 +1334,6 @@ func (er erasureObjects) CompleteMultipartUpload(ctx context.Context, bucket str
 		}
 	}
 
-	if !opts.NoLock {
-		lk := er.NewNSLock(bucket, object)
-		lkctx, err := lk.GetLock(ctx, globalOperationTimeout)
-		if err != nil {
-			return ObjectInfo{}, err
-		}
-		ctx = lkctx.Context()
-		defer lk.Unlock(lkctx)
-	}
-
 	// Accept encrypted checksum from incoming request.
 	if opts.UserDefined[ReplicationSsecChecksumHeader] != "" {
 		if v, err := base64.StdEncoding.DecodeString(opts.UserDefined[ReplicationSsecChecksumHeader]); err == nil {
@@ -1419,6 +1412,16 @@ func (er erasureObjects) CompleteMultipartUpload(ctx context.Context, bucket str
 		}
 	}
 
+	if !opts.NoLock {
+		lk := er.NewNSLock(bucket, object)
+		lkctx, err := lk.GetLock(ctx, globalOperationTimeout)
+		if err != nil {
+			return ObjectInfo{}, err
+		}
+		ctx = lkctx.Context()
+		defer lk.Unlock(lkctx)
+	}
+
 	er.cleanupMultipartPath(ctx, paths...) // cleanup all part.N.meta, and skipped part.N's before final rename().
 
 	defer func() {

cmd/erasure-object.go

@@ -1333,12 +1333,12 @@ func (er erasureObjects) putObject(ctx context.Context, bucket string, object st
 	if opts.EncryptFn != nil {
 		fi.Checksum = opts.EncryptFn("object-checksum", fi.Checksum)
 	}
-	if userDefined[ReplicationSsecChecksumHeader] != "" {
+	if ckSum := userDefined[ReplicationSsecChecksumHeader]; ckSum != "" {
-		if v, err := base64.StdEncoding.DecodeString(userDefined[ReplicationSsecChecksumHeader]); err == nil {
+		if v, err := base64.StdEncoding.DecodeString(ckSum); err == nil {
 			fi.Checksum = v
 		}
-	}
 		delete(userDefined, ReplicationSsecChecksumHeader)
+	}
 	uniqueID := mustGetUUID()
 	tempObj := uniqueID
 
@@ -1436,15 +1436,6 @@ func (er erasureObjects) putObject(ctx context.Context, bucket string, object st
 	if opts.IndexCB != nil {
 		compIndex = opts.IndexCB()
 	}
-	if !opts.NoLock {
-		lk := er.NewNSLock(bucket, object)
-		lkctx, err := lk.GetLock(ctx, globalOperationTimeout)
-		if err != nil {
-			return ObjectInfo{}, err
-		}
-		ctx = lkctx.Context()
-		defer lk.Unlock(lkctx)
-	}
 
 	modTime := opts.MTime
 	if opts.MTime.IsZero() {
@@ -1521,6 +1512,16 @@ func (er erasureObjects) putObject(ctx context.Context, bucket string, object st
 		}
 	}
 
+	if !opts.NoLock {
+		lk := er.NewNSLock(bucket, object)
+		lkctx, err := lk.GetLock(ctx, globalOperationTimeout)
+		if err != nil {
+			return ObjectInfo{}, err
+		}
+		ctx = lkctx.Context()
+		defer lk.Unlock(lkctx)
+	}
+
 	// Rename the successfully written temporary object to final location.
 	onlineDisks, versions, oldDataDir, err := renameData(ctx, onlineDisks, minioMetaTmpBucket, tempObj, partsMetadata, bucket, object, writeQuorum)
 	if err != nil {

cmd/erasure-server-pool.go

@@ -1091,18 +1091,7 @@ func (z *erasureServerPools) PutObject(ctx context.Context, bucket string, objec
 		return z.serverPools[0].PutObject(ctx, bucket, object, data, opts)
 	}
 
-	if !opts.NoLock {
+	idx, err := z.getPoolIdx(ctx, bucket, object, data.Size())
-		ns := z.NewNSLock(bucket, object)
-		lkctx, err := ns.GetLock(ctx, globalOperationTimeout)
-		if err != nil {
-			return ObjectInfo{}, err
-		}
-		ctx = lkctx.Context()
-		defer ns.Unlock(lkctx)
-		opts.NoLock = true
-	}
-
-	idx, err := z.getPoolIdxNoLock(ctx, bucket, object, data.Size())
 	if err != nil {
 		return ObjectInfo{}, err
 	}
@@ -1115,7 +1104,7 @@ func (z *erasureServerPools) PutObject(ctx context.Context, bucket string, objec
 			Err:       errDataMovementSrcDstPoolSame,
 		}
 	}
-	// Overwrite the object at the right pool
+
 	return z.serverPools[idx].PutObject(ctx, bucket, object, data, opts)
 }