diff --git a/models/mail.go b/models/mail.go
index 77856553c..04e571ae5 100644
--- a/models/mail.go
+++ b/models/mail.go
@@ -23,12 +23,12 @@ const (
 	MailAuthActivate        base.TplName = "auth/activate"
 	MailAuthActivateEmail  base.TplName = "auth/activate_email"
 	MailAuthResetPassword  base.TplName = "auth/reset_passwd"
-	MAIL_AUTH_REGISTER_NOTIFY base.TplName = "auth/register_notify"
+	MailAuthRegisterNotify base.TplName = "auth/register_notify"
 
-	MAIL_ISSUE_COMMENT base.TplName = "issue/comment"
-	MAIL_ISSUE_MENTION base.TplName = "issue/mention"
+	MailIssueComment base.TplName = "issue/comment"
+	MailIssueMention base.TplName = "issue/mention"
 
-	MAIL_NOTIFY_COLLABORATOR base.TplName = "notify/collaborator"
+	MailNotifyCollaborator base.TplName = "notify/collaborator"
 )
 
 type MailRender interface {
@@ -109,7 +109,7 @@ func SendRegisterNotifyMail(c *macaron.Context, u *User) {
 	data := map[string]interface{}{
 		"Username": u.DisplayName(),
 	}
-	body, err := mailRender.HTMLString(string(MAIL_AUTH_REGISTER_NOTIFY), data)
+	body, err := mailRender.HTMLString(string(MailAuthRegisterNotify), data)
 	if err != nil {
 		log.Error(3, "HTMLString: %v", err)
 		return
@@ -131,7 +131,7 @@ func SendCollaboratorMail(u, doer *User, repo *Repository) {
 		"RepoName": repoName,
 		"Link":     repo.HTMLURL(),
 	}
-	body, err := mailRender.HTMLString(string(MAIL_NOTIFY_COLLABORATOR), data)
+	body, err := mailRender.HTMLString(string(MailNotifyCollaborator), data)
 	if err != nil {
 		log.Error(3, "HTMLString: %v", err)
 		return
@@ -171,7 +171,7 @@ func SendIssueCommentMail(issue *Issue, doer *User, tos []string) {
 		return
 	}
 
-	mailer.SendAsync(composeIssueMessage(issue, doer, MAIL_ISSUE_COMMENT, tos, "issue comment"))
+	mailer.SendAsync(composeIssueMessage(issue, doer, MailIssueComment, tos, "issue comment"))
 }
 
 // SendIssueMentionMail composes and sends issue mention emails to target receivers.
@@ -179,5 +179,5 @@ func SendIssueMentionMail(issue *Issue, doer *User, tos []string) {
 	if len(tos) == 0 {
 		return
 	}
-	mailer.SendAsync(composeIssueMessage(issue, doer, MAIL_ISSUE_MENTION, tos, "issue mention"))
+	mailer.SendAsync(composeIssueMessage(issue, doer, MailIssueMention, tos, "issue mention"))
 }
diff --git a/models/repo.go b/models/repo.go
index 5c5af32f4..edf5de932 100644
--- a/models/repo.go
+++ b/models/repo.go
@@ -1613,18 +1613,18 @@ func RewriteRepositoryUpdateHook() error {
 var taskStatusTable = sync.NewStatusTable()
 
 const (
-	_MIRROR_UPDATE = "mirror_update"
-	_GIT_FSCK      = "git_fsck"
-	_CHECK_REPOs   = "check_repos"
+	mirrorUpdate = "mirror_update"
+	gitFsck      = "git_fsck"
+	checkRepos   = "check_repos"
 )
 
 // GitFsck calls 'git fsck' to check repository health.
 func GitFsck() {
-	if taskStatusTable.IsRunning(_GIT_FSCK) {
+	if taskStatusTable.IsRunning(gitFsck) {
 		return
 	}
-	taskStatusTable.Start(_GIT_FSCK)
-	defer taskStatusTable.Stop(_GIT_FSCK)
+	taskStatusTable.Start(gitFsck)
+	defer taskStatusTable.Stop(gitFsck)
 
 	log.Trace("Doing: GitFsck")
 
@@ -1686,11 +1686,11 @@ func repoStatsCheck(checker *repoChecker) {
 }
 
 func CheckRepoStats() {
-	if taskStatusTable.IsRunning(_CHECK_REPOs) {
+	if taskStatusTable.IsRunning(checkRepos) {
 		return
 	}
-	taskStatusTable.Start(_CHECK_REPOs)
-	defer taskStatusTable.Stop(_CHECK_REPOs)
+	taskStatusTable.Start(checkRepos)
+	defer taskStatusTable.Stop(checkRepos)
 
 	log.Trace("Doing: CheckRepoStats")
 
diff --git a/models/repo_mirror.go b/models/repo_mirror.go
index 9688f579a..c598f82bf 100644
--- a/models/repo_mirror.go
+++ b/models/repo_mirror.go
@@ -191,11 +191,11 @@ func DeleteMirrorByRepoID(repoID int64) error {
 
 // MirrorUpdate checks and updates mirror repositories.
 func MirrorUpdate() {
-	if taskStatusTable.IsRunning(_MIRROR_UPDATE) {
+	if taskStatusTable.IsRunning(mirrorUpdate) {
 		return
 	}
-	taskStatusTable.Start(_MIRROR_UPDATE)
-	defer taskStatusTable.Stop(_MIRROR_UPDATE)
+	taskStatusTable.Start(mirrorUpdate)
+	defer taskStatusTable.Stop(mirrorUpdate)
 
 	log.Trace("Doing: MirrorUpdate")