Revert "database/sql: prevent race in driver by locking dc in Next"
This reverts commit 897080d5cbb1793f8ad3ef5fb7c6fafba2e97d42.
Reason for revert: Fails to fix all the locking issues.
Updates #21117
Change-Id: I6fc9cb7897244d6e1af78c089a2bf383258ec049
Reviewed-on: https://go-review.googlesource.com/71450
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/database/sql/fakedb_test.go b/src/database/sql/fakedb_test.go
index 8e77df4..4dcd096 100644
--- a/src/database/sql/fakedb_test.go
+++ b/src/database/sql/fakedb_test.go
@@ -943,7 +943,6 @@
}
func (rc *rowsCursor) touchMem() {
- rc.parentMem.touchMem()
rc.line++
}
diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go
index 9a3957b..1791090 100644
--- a/src/database/sql/sql.go
+++ b/src/database/sql/sql.go
@@ -2491,12 +2491,6 @@
if rs.lastcols == nil {
rs.lastcols = make([]driver.Value, len(rs.rowsi.Columns()))
}
-
- // Lock the driver connection before calling the driver interface
- // rowsi to prevent a Tx from rolling back the connection at the same time.
- rs.dc.Lock()
- defer rs.dc.Unlock()
-
rs.lasterr = rs.rowsi.Next(rs.lastcols)
if rs.lasterr != nil {
// Close the connection if there is a driver error.
@@ -2546,12 +2540,6 @@
doClose = true
return false
}
-
- // Lock the driver connection before calling the driver interface
- // rowsi to prevent a Tx from rolling back the connection at the same time.
- rs.dc.Lock()
- defer rs.dc.Unlock()
-
rs.lasterr = nextResultSet.NextResultSet()
if rs.lasterr != nil {
doClose = true
diff --git a/src/database/sql/sql_test.go b/src/database/sql/sql_test.go
index 760159a..046d95a 100644
--- a/src/database/sql/sql_test.go
+++ b/src/database/sql/sql_test.go
@@ -3127,9 +3127,6 @@
// In the test, a context is canceled while the query is in process so
// the internal rollback will run concurrently with the explicitly called
// Tx.Rollback.
-//
-// The addition of calling rows.Next also tests
-// Issue 21117.
func TestIssue18429(t *testing.T) {
db := newTestDB(t, "people")
defer closeDB(t, db)
@@ -3140,7 +3137,7 @@
const milliWait = 30
- for i := 0; i < 1000; i++ {
+ for i := 0; i < 100; i++ {
sem <- true
wg.Add(1)
go func() {
@@ -3162,9 +3159,6 @@
// reported.
rows, _ := tx.QueryContext(ctx, "WAIT|"+qwait+"|SELECT|people|name|")
if rows != nil {
- // Call Next to test Issue 21117 and check for races.
- for rows.Next() {
- }
rows.Close()
}
// This call will race with the context cancel rollback to complete
