diff options
| author | Joel Sing <joel@sing.id.au> | 2019-05-07 17:56:49 +1000 |
|---|---|---|
| committer | Joel Sing <joel@sing.id.au> | 2019-05-15 18:12:10 +0000 |
| commit | ab242dcbc92803788b135816823536c4007137e3 (patch) | |
| tree | e50ecb886fcadf648adf4777a69a2785f9ac5481 /src/syscall/exec_linux.go | |
| parent | 38431f1044880b936e35034ded19a6a8bc9faa21 (diff) | |
| download | go-ab242dcbc92803788b135816823536c4007137e3.tar.xz | |
syscall: implement rawVforkSyscall for linux/ppc64x and linux/s390x
This allows the use of CLONE_VFORK and CLONE_VM for fork/exec, preventing
"fork/exec ...: cannot allocate memory" failures from occuring when attempting
to execute commands from a Go process that has a large memory footprint.
Additionally, this should reduce the latency of fork/exec on these platforms.
The same problem was addressed on linux/amd64 via issue #5838.
Updates #31936
Change-Id: I7ae0fbbeaa29cab944a49a11272a380d497eb2d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/175697
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Diffstat (limited to 'src/syscall/exec_linux.go')
| -rw-r--r-- | src/syscall/exec_linux.go | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/src/syscall/exec_linux.go b/src/syscall/exec_linux.go index 3493f4b32b..a2242b2057 100644 --- a/src/syscall/exec_linux.go +++ b/src/syscall/exec_linux.go @@ -196,12 +196,14 @@ func forkAndExecInChild1(argv0 *byte, argv, envv []*byte, chroot, dir *byte, att } } + hasRawVforkSyscall := runtime.GOARCH == "amd64" || runtime.GOARCH == "ppc64" || runtime.GOARCH == "s390x" + // About to call fork. // No more allocation or calls of non-assembly functions. runtime_BeforeFork() locked = true switch { - case runtime.GOARCH == "amd64" && (sys.Cloneflags&CLONE_NEWUSER == 0 && sys.Unshareflags&CLONE_NEWUSER == 0): + case hasRawVforkSyscall && (sys.Cloneflags&CLONE_NEWUSER == 0 && sys.Unshareflags&CLONE_NEWUSER == 0): r1, err1 = rawVforkSyscall(SYS_CLONE, uintptr(SIGCHLD|CLONE_VFORK|CLONE_VM)|sys.Cloneflags) case runtime.GOARCH == "s390x": r1, _, err1 = RawSyscall6(SYS_CLONE, 0, uintptr(SIGCHLD)|sys.Cloneflags, 0, 0, 0, 0) |