Use errgroups instead of sync.WaitGroup as needed (#8354)

cmd/xl-v1-multipart.go

@@ -24,12 +24,12 @@ import (
 	"sort"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
 
 	xhttp "github.com/minio/minio/cmd/http"
 	"github.com/minio/minio/cmd/logger"
 	"github.com/minio/minio/pkg/mimedb"
+	"github.com/minio/minio/pkg/sync/errgroup"
 )
 
 func (xl xlObjects) getUploadIDDir(bucket, object, uploadID string) string {
@@ -57,21 +57,23 @@ func (xl xlObjects) checkUploadIDExists(ctx context.Context, bucket, object, upl
 // Removes part given by partName belonging to a mulitpart upload from minioMetaBucket
 func (xl xlObjects) removeObjectPart(bucket, object, uploadID, partName string) {
 	curpartPath := path.Join(bucket, object, uploadID, partName)
-	var wg sync.WaitGroup
-	for i, disk := range xl.getDisks() {
+	storageDisks := xl.getDisks()
+
+	g := errgroup.WithNErrs(len(storageDisks))
+	for index, disk := range storageDisks {
 		if disk == nil {
 			continue
 		}
-		wg.Add(1)
-		go func(index int, disk StorageAPI) {
-			defer wg.Done()
+		index := index
+		g.Go(func() error {
 			// Ignoring failure to remove parts that weren't present in CompleteMultipartUpload
 			// requests. xl.json is the authoritative source of truth on which parts constitute
 			// the object. The presence of parts that don't belong in the object doesn't affect correctness.
-			_ = disk.DeleteFile(minioMetaMultipartBucket, curpartPath)
-		}(i, disk)
+			_ = storageDisks[index].DeleteFile(minioMetaMultipartBucket, curpartPath)
+			return nil
+		}, index)
 	}
-	wg.Wait()
+	g.Wait()
 }
 
 // statPart - returns fileInfo structure for a successful stat on part file.
@@ -104,31 +106,29 @@ func (xl xlObjects) statPart(ctx context.Context, bucket, object, uploadID, part
 
 // commitXLMetadata - commit `xl.json` from source prefix to destination prefix in the given slice of disks.
 func commitXLMetadata(ctx context.Context, disks []StorageAPI, srcBucket, srcPrefix, dstBucket, dstPrefix string, quorum int) ([]StorageAPI, error) {
-	var wg sync.WaitGroup
-	var mErrs = make([]error, len(disks))
-
 	srcJSONFile := path.Join(srcPrefix, xlMetaJSONFile)
 	dstJSONFile := path.Join(dstPrefix, xlMetaJSONFile)
 
+	g := errgroup.WithNErrs(len(disks))
+
 	// Rename `xl.json` to all disks in parallel.
-	for index, disk := range disks {
-		if disk == nil {
-			mErrs[index] = errDiskNotFound
-			continue
-		}
-		wg.Add(1)
-		// Rename `xl.json` in a routine.
-		go func(index int, disk StorageAPI) {
-			defer wg.Done()
+	for index := range disks {
+		index := index
+		g.Go(func() error {
+			if disks[index] == nil {
+				return errDiskNotFound
+			}
+
 			// Delete any dangling directories.
-			defer disk.DeleteFile(srcBucket, srcPrefix)
+			defer disks[index].DeleteFile(srcBucket, srcPrefix)
 
 			// Renames `xl.json` from source prefix to destination prefix.
-			mErrs[index] = disk.RenameFile(srcBucket, srcJSONFile, dstBucket, dstJSONFile)
-		}(index, disk)
+			return disks[index].RenameFile(srcBucket, srcJSONFile, dstBucket, dstJSONFile)
+		}, index)
 	}
+
 	// Wait for all the routines.
-	wg.Wait()
+	mErrs := g.Wait()
 
 	err := reduceWriteQuorumErrs(ctx, mErrs, objectOpIgnoredErrs, quorum)
 	return evalDisks(disks, mErrs), err