Merge pull request #813 from xiaobo55x:pkg_sleep

PiperOrigin-RevId: 273668431

1 files changed, 38 insertions, 0 deletions

diff --git a/pkg/sleep/commit_arm64.s b/pkg/sleep/commit_arm64.s
new file mode 100644
index 000000000..d0ef15b20
--- /dev/null
+++ b/pkg/sleep/commit_arm64.s
@@ -0,0 +1,38 @@
+// Copyright 2019 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "textflag.h"
+
+#define preparingG 1
+
+// See commit_noasm.go for a description of commitSleep.
+//
+// func commitSleep(g uintptr, waitingG *uintptr) bool
+TEXT ·commitSleep(SB),NOSPLIT,$0-24
+	MOVD waitingG+8(FP), R0
+	MOVD $preparingG, R1
+	MOVD G+0(FP), R2
+
+	// Store the G in waitingG if it's still preparingG. If it's anything
+	// else it means a waker has aborted the sleep.
+again:
+        LDAXR   (R0), R3
+        CMP     R1, R3
+        BNE     ok
+        STLXR   R2, (R0), R3
+        CBNZ    R3, again
+ok:
+        CSET    EQ, R0
+        MOVB    R0, ret+16(FP)
+        RET