Merge pull request #2302 from Luap99/driver-mutex

fix minor review comment about the driver mutex and a minor lint issue

Author: openshift-merge-bot[bot]

.cirrus.yml

@@ -126,7 +126,7 @@ lint_task:
         folder: $GOPATH/pkg/mod
     build_script: |
       apt-get update
-      apt-get install -y libbtrfs-dev
+      apt-get install -y libbtrfs-dev libsubid-dev
     test_script: |
       make TAGS=regex_precompile local-validate
       make lint

drivers/overlay/overlay.go

@@ -130,7 +130,7 @@ type Driver struct {
 	usingMetacopy    bool
 	usingComposefs   bool
 
-	stagingDirsLocksMutex *sync.Mutex
+	stagingDirsLocksMutex sync.Mutex
 	// stagingDirsLocks access is not thread safe, it is required that callers take
 	// stagingDirsLocksMutex on each access to guard against concurrent map writes.
 	stagingDirsLocks map[string]*lockfile.LockFile
@@ -441,7 +441,7 @@ func Init(home string, options graphdriver.Options) (graphdriver.Driver, error)
 		supportsVolatile:      supportsVolatile,
 		usingComposefs:        opts.useComposefs,
 		options:               *opts,
-		stagingDirsLocksMutex: &sync.Mutex{},
+		stagingDirsLocksMutex: sync.Mutex{},
 		stagingDirsLocks:      make(map[string]*lockfile.LockFile),
 	}
 

hack/libsubid_tag.sh

@@ -5,7 +5,7 @@ fi
 tmpdir="$PWD/tmp.$RANDOM"
 mkdir -p "$tmpdir"
 trap 'rm -fr "$tmpdir"' EXIT
-cc -o "$tmpdir"/libsubid_tag -l subid -x c - > /dev/null 2> /dev/null << EOF
+cc -o "$tmpdir"/libsubid_tag -x c - -l subid > /dev/null 2> /dev/null << EOF
 #include <shadow/subid.h>
 #include <stdio.h>
 #include <stdlib.h>

pkg/idtools/idtools_supported.go

@@ -29,9 +29,7 @@ struct subid_range get_range(struct subid_range *ranges, int i)
 */
 import "C"
 
-var (
-	onceInit sync.Once
-)
+var onceInit sync.Once
 
 func readSubid(username string, isUser bool) (ranges, error) {
 	var ret ranges