cherry pick #569 to release-4.0 (#721)

Signed-off-by: ti-srebot <ti-srebot@pingcap.com>

Co-authored-by: lvtu <37565148+tongtongyin@users.noreply.github.com>
Co-authored-by: 3pointer <luancheng@pingcap.com>
Co-authored-by: glorv <glorvs@163.com>

pkg/backup/push.go

@@ -17,7 +17,7 @@ import (
 	"github.com/pingcap/br/pkg/rtree"
 )
 
-// pushDown warps a backup task.
+// pushDown wraps a backup task.
 type pushDown struct {
 	mgr    ClientMgr
 	respCh chan *backup.BackupResponse

pkg/restore/batcher.go

@@ -274,7 +274,7 @@ func (b *Batcher) drainRanges() DrainResult {
 
 		// the batch is full, we should stop here!
 		// we use strictly greater than because when we send a batch at equal, the offset should plus one.
-		// (because the last table is sent, we should put it in emptyTables), and this will intrduce extra complex.
+		// (because the last table is sent, we should put it in emptyTables), and this will introduce extra complex.
 		if thisTableLen+collected > b.batchSizeThreshold {
 			drainSize := b.batchSizeThreshold - collected
 			thisTableRanges := thisTable.Range

pkg/restore/pipeline_items.go

@@ -72,7 +72,7 @@ func NewBRContextManager(client *Client) ContextManager {
 type brContextManager struct {
 	client *Client
 
-	// This 'set' of table ID allow us handle each table just once.
+	// This 'set' of table ID allow us to handle each table just once.
 	hasTable map[int64]CreatedTable
 }
 

pkg/restore/split.go

@@ -255,7 +255,7 @@ func (rs *RegionSplitter) splitAndScatterRegions(
 		return nil, errors.Trace(err)
 	}
 	for _, region := range newRegions {
-		// Wait for a while until the regions successfully splits.
+		// Wait for a while until the regions successfully split.
 		rs.waitForSplit(ctx, region.Region.Id)
 		if err = rs.client.ScatterRegion(ctx, region); err != nil {
 			log.Warn("scatter region failed", logutil.Region(region.Region), zap.Error(err))