database/sql: deflake TestPendingConnsAfterErr and fix races, panics
TestPendingConnsAfterErr only cared that things didn't deadlock, so 5
seconds is a sufficient timer. We don't need 100 milliseconds.
I was able to reproduce with a tiny (5 nanosecond) timeout value,
instead of 100 milliseconds. In the process of testing with -race and
a high -count= value, I noticed several data races and panics
(sendings on a closed channel) which are also fixed in this change.
Fixes #15684
Change-Id: Ib4605fcc0f296e658cb948352ed642b801cb578c
Reviewed-on: https://go-review.googlesource.com/24550
Reviewed-by: Marko Tiikkaja <marko@joh.to>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Andrew Gerrand <adg@golang.org>
diff --git a/src/database/sql/sql.go b/src/database/sql/sql.go
index e7482a8..09de1c3 100644
--- a/src/database/sql/sql.go
+++ b/src/database/sql/sql.go
@@ -718,6 +718,9 @@
for numRequests > 0 {
db.numOpen++ // optimistically
numRequests--
+ if db.closed {
+ return
+ }
db.openerCh <- struct{}{}
}
}
@@ -915,6 +918,9 @@
// If a connRequest was fulfilled or the *driverConn was placed in the
// freeConn list, then true is returned, otherwise false is returned.
func (db *DB) putConnDBLocked(dc *driverConn, err error) bool {
+ if db.closed {
+ return false
+ }
if db.maxOpen > 0 && db.numOpen > db.maxOpen {
return false
}
diff --git a/src/database/sql/sql_test.go b/src/database/sql/sql_test.go
index 6f11303..08df0c7 100644
--- a/src/database/sql/sql_test.go
+++ b/src/database/sql/sql_test.go
@@ -144,7 +144,7 @@
count := db.numOpen
db.mu.Unlock()
if count != 0 {
- t.Fatalf("%d connections still open after closing DB", db.numOpen)
+ t.Fatalf("%d connections still open after closing DB", count)
}
}
@@ -1239,7 +1239,7 @@
time.Sleep(10 * time.Millisecond) // make extra sure all workers are blocked
close(unblock) // let all workers proceed
- const timeout = 100 * time.Millisecond
+ const timeout = 5 * time.Second
to := time.NewTimer(timeout)
defer to.Stop()
@@ -1615,6 +1615,8 @@
}
}()
+ db.mu.Lock()
+ defer db.mu.Unlock()
if db.numOpen != nconn {
t.Fatalf("unexpected numOpen %d (was expecting %d)", db.numOpen, nconn)
} else if len(db.freeConn) != nconn {
