From 292366e7162a030cade7b177eb4ad55bd887d25f Mon Sep 17 00:00:00 2001 From: Daniel Theophanes Date: Tue, 17 Oct 2017 22:04:17 +0000 Subject: [PATCH] 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 --- src/database/sql/fakedb_test.go | 1 - src/database/sql/sql.go | 12 ------------ src/database/sql/sql_test.go | 8 +------- 3 files changed, 1 insertion(+), 20 deletions(-) diff --git a/src/database/sql/fakedb_test.go b/src/database/sql/fakedb_test.go index 8e77df4ace8..4dcd096ca4d 100644 --- a/src/database/sql/fakedb_test.go +++ b/src/database/sql/fakedb_test.go @@ -943,7 +943,6 @@ type rowsCursor struct { } func (rc *rowsCursor) touchMem() { - rc.parentMem.touchMem() rc.line++ } diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go index 9a3957b267f..17910904f62 100644 --- a/src/database/sql/sql.go +++ b/src/database/sql/sql.go @@ -2491,12 +2491,6 @@ func (rs *Rows) nextLocked() (doClose, ok bool) { 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 @@ func (rs *Rows) NextResultSet() bool { 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 760159a9acd..046d95aff47 100644 --- a/src/database/sql/sql_test.go +++ b/src/database/sql/sql_test.go @@ -3127,9 +3127,6 @@ func TestIssue6081(t *testing.T) { // 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 @@ func TestIssue18429(t *testing.T) { 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 @@ func TestIssue18429(t *testing.T) { // 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