[go] net: use runtime.Keepalive for *netFD values

[Ian Lance Taylor (Gerrit)]

Ian Lance Taylor uploaded a change:
https://go-review.googlesource.com/27650

net: use runtime.Keepalive for *netFD values

The net package sets a finalizer on *netFD. I looked through all the
uses of *netFD in the package, looking for each case where a *netFD
was passed as an argument and the final reference to the argument was
not a function or method call. I added a call to runtime.KeepAlive after
each such final reference (there were only three).

The code is safe today without the KeepAlive calls because the compiler
keeps arguments alive for the duration of the function. However, that is
not a language requirement, so adding the KeepAlive calls ensures that
this code remains safe even if the compiler changes in the future.

Change-Id: I4e2bd7c5a946035dc509ccefb4828f72335a9ee3
---
M src/net/fd_poll_nacl.go
M src/net/fd_poll_runtime.go
M src/net/fd_windows.go
3 files changed, 4 insertions(+), 1 deletion(-)



diff --git a/src/net/fd_poll_nacl.go b/src/net/fd_poll_nacl.go
index cda8b82..5fde2d2 100644
--- a/src/net/fd_poll_nacl.go
+++ b/src/net/fd_poll_nacl.go
@@ -22,6 +22,7 @@
pd.closing = true
if pd.fd != nil {
syscall.StopIO(pd.fd.sysfd)
+ runtime.KeepAlive(pd.fd)
}
}

diff --git a/src/net/fd_poll_runtime.go b/src/net/fd_poll_runtime.go
index 6c1d095..bfa62c9 100644
--- a/src/net/fd_poll_runtime.go
+++ b/src/net/fd_poll_runtime.go
@@ -7,6 +7,7 @@
package net

import (
+ "runtime"
"sync"
"syscall"
"time"
@@ -33,6 +34,7 @@
func (pd *pollDesc) init(fd *netFD) error {
serverInit.Do(runtime_pollServerInit)
ctx, errno := runtime_pollOpen(uintptr(fd.sysfd))
+ runtime.KeepAlive(fd)
if errno != 0 {
return syscall.Errno(errno)
}
diff --git a/src/net/fd_windows.go b/src/net/fd_windows.go
index b0b6769..d1c368e 100644
--- a/src/net/fd_windows.go
+++ b/src/net/fd_windows.go
@@ -541,7 +541,7 @@
netfd.Close()
return nil, os.NewSyscallError("setsockopt", err)
}
-
+ runtime.KeepAlive(fd)
return netfd, nil
}


--
https://go-review.googlesource.com/27650

[Gobot Gobot (Gerrit)]

Gobot Gobot has posted comments on this change.

net: use runtime.Keepalive for *netFD values

Patch Set 1:

TryBots beginning. Status page: http://farmer.golang.org/try?commit=4273b10b

--
https://go-review.googlesource.com/27650
Gerrit-Reviewer: Gobot Gobot <go...@golang.org>
Gerrit-HasComments: No

[Gobot Gobot (Gerrit)]

Gobot Gobot has posted comments on this change.

net: use runtime.Keepalive for *netFD values

Patch Set 1:

Build is still in progress...
This change failed on nacl-386:
See
https://storage.googleapis.com/go-build-log/4273b10b/nacl-386_7e822ff4.log

Consult https://build.golang.org/ to see whether it's a new failure. Other
builds still in progress; subsequent failure notices suppressed until final
report.

[Gobot Gobot (Gerrit)]

Gobot Gobot has posted comments on this change.

net: use runtime.Keepalive for *netFD values

Patch Set 1: TryBot-Result-1

3 of 18 TryBots failed:
Failed on nacl-386:
https://storage.googleapis.com/go-build-log/4273b10b/nacl-386_7e822ff4.log
Failed on nacl-amd64p32:
https://storage.googleapis.com/go-build-log/4273b10b/nacl-amd64p32_ef92d995.log
Failed on misc-compile:
https://storage.googleapis.com/go-build-log/4273b10b/misc-compile_ece3e5cf.log

Consult https://build.golang.org/ to see whether they are new failures.

[Ian Lance Taylor (Gerrit)]

Reviewers: Gobot Gobot

Ian Lance Taylor uploaded a new patch set:

https://go-review.googlesource.com/27650

net: use runtime.Keepalive for *netFD values

The net package sets a finalizer on *netFD. I looked through all the
uses of *netFD in the package, looking for each case where a *netFD
was passed as an argument and the final reference to the argument was
not a function or method call. I added a call to runtime.KeepAlive after
each such final reference (there were only three).

The code is safe today without the KeepAlive calls because the compiler
keeps arguments alive for the duration of the function. However, that is
not a language requirement, so adding the KeepAlive calls ensures that
this code remains safe even if the compiler changes in the future.

Change-Id: I4e2bd7c5a946035dc509ccefb4828f72335a9ee3
---
M src/net/fd_poll_nacl.go
M src/net/fd_poll_runtime.go
M src/net/fd_windows.go

3 files changed, 5 insertions(+), 1 deletion(-)

[Gobot Gobot (Gerrit)]

Gobot Gobot has posted comments on this change.

net: use runtime.Keepalive for *netFD values

Patch Set 2:

TryBots beginning. Status page: http://farmer.golang.org/try?commit=275c2ebe

--
https://go-review.googlesource.com/27650
Gerrit-Reviewer: Gobot Gobot <go...@golang.org>

Gerrit-HasComments: No

[Brad Fitzpatrick (Gerrit)]

Brad Fitzpatrick has posted comments on this change.

net: use runtime.Keepalive for *netFD values

Patch Set 2: Code-Review+2

--
https://go-review.googlesource.com/27650
Gerrit-Reviewer: Brad Fitzpatrick <brad...@golang.org>

[Gobot Gobot (Gerrit)]

Gobot Gobot has posted comments on this change.

net: use runtime.Keepalive for *netFD values

Patch Set 2: TryBot-Result+1

TryBots are happy.

[Ian Lance Taylor (Gerrit)]

Ian Lance Taylor has submitted this change and it was merged.

net: use runtime.Keepalive for *netFD values

The net package sets a finalizer on *netFD. I looked through all the
uses of *netFD in the package, looking for each case where a *netFD
was passed as an argument and the final reference to the argument was
not a function or method call. I added a call to runtime.KeepAlive after
each such final reference (there were only three).

The code is safe today without the KeepAlive calls because the compiler
keeps arguments alive for the duration of the function. However, that is
not a language requirement, so adding the KeepAlive calls ensures that
this code remains safe even if the compiler changes in the future.

Change-Id: I4e2bd7c5a946035dc509ccefb4828f72335a9ee3

Reviewed-on: https://go-review.googlesource.com/27650
Run-TryBot: Ian Lance Taylor <ia...@golang.org>
Reviewed-by: Brad Fitzpatrick <brad...@golang.org>
TryBot-Result: Gobot Gobot <go...@golang.org>

---
M src/net/fd_poll_nacl.go
M src/net/fd_poll_runtime.go
M src/net/fd_windows.go

3 files changed, 5 insertions(+), 1 deletion(-)

Approvals:
Gobot Gobot: TryBots succeeded
Brad Fitzpatrick: Looks good to me, approved
Ian Lance Taylor: Run TryBots

--
https://go-review.googlesource.com/27650
Gerrit-Reviewer: Brad Fitzpatrick <brad...@golang.org>
Gerrit-Reviewer: Gobot Gobot <go...@golang.org>

Gerrit-Reviewer: Ian Lance Taylor <ia...@golang.org>