commit ea3c546e9e2b507d497f8093f8414cb31c112062
author Tamir Duberstein <tamird@google.com> Thu Jan 27 15:29:04 2022 +0000
committer Ian Lance Taylor <iant@golang.org> Wed Feb 09 22:06:20 2022 +0000
tree 2d0653eedb6d9f014941e6c774a71f0ea931baf8
parent 2e2ef31778800856d9db87ad06cc963ef2530eeb

syscall: use RLIMIT_CPU instead of RLIMIT_NOFILE

The latter is subject to kern.maxfilelimit restrictions on darwin which
are not reflected in the return value. This makes it difficult to
reliably restore the default after the test is complete. RLIMIT_CPU
should hopefully sidestep this problem.

Updates #40564.

Change-Id: Ifb33c7d46f2708130cef366dc245c643a2d5e465
Reviewed-on: https://go-review.googlesource.com/c/go/+/383234
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Trust: Bryan Mills <bcmills@google.com>

src/syscall/syscall_unix_test.go

diff --git a/src/syscall/syscall_unix_test.go b/src/syscall/syscall_unix_test.go
index e4af0ba..1ef2634 100644
--- a/src/syscall/syscall_unix_test.go
+++ b/src/syscall/syscall_unix_test.go
@@ -328,8 +328,7 @@
 
 func TestRlimit(t *testing.T) {
 	var rlimit, zero syscall.Rlimit
-	err := syscall.Getrlimit(syscall.RLIMIT_NOFILE, &rlimit)
-	if err != nil {
+	if err := syscall.Getrlimit(syscall.RLIMIT_CPU, &rlimit); err != nil {
 		t.Fatalf("Getrlimit: save failed: %v", err)
 	}
 	if zero == rlimit {
@@ -337,31 +336,19 @@
 	}
 	set := rlimit
 	set.Cur = set.Max - 1
-	if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && set.Cur > 4096 {
-		// rlim_min for RLIMIT_NOFILE should be equal to
-		// or lower than kern.maxfilesperproc, which on
-		// some machines are 4096. See #40564.
-		set.Cur = 4096
-	}
-	err = syscall.Setrlimit(syscall.RLIMIT_NOFILE, &set)
-	if err != nil {
+	if err := syscall.Setrlimit(syscall.RLIMIT_CPU, &set); err != nil {
 		t.Fatalf("Setrlimit: set failed: %#v %v", set, err)
 	}
 	var get syscall.Rlimit
-	err = syscall.Getrlimit(syscall.RLIMIT_NOFILE, &get)
-	if err != nil {
+	if err := syscall.Getrlimit(syscall.RLIMIT_CPU, &get); err != nil {
 		t.Fatalf("Getrlimit: get failed: %v", err)
 	}
 	set = rlimit
 	set.Cur = set.Max - 1
-	if (runtime.GOOS == "darwin" || runtime.GOOS == "ios") && set.Cur > 4096 {
-		set.Cur = 4096
-	}
 	if set != get {
 		t.Fatalf("Rlimit: change failed: wanted %#v got %#v", set, get)
 	}
-	err = syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rlimit)
-	if err != nil {
+	if err := syscall.Setrlimit(syscall.RLIMIT_CPU, &rlimit); err != nil {
 		t.Fatalf("Setrlimit: restore failed: %#v %v", rlimit, err)
 	}
 }