From 4047f300c9defec5b0fc0d6801f29c03c4873af9 Mon Sep 17 00:00:00 2001
From: Joel Sing <jsing@google.com>
Date: Mon, 26 Nov 2012 22:34:01 +1100
Subject: [PATCH] runtime: implement SysUnused for netbsd

R=golang-dev, bradfitz, minux.ma, dave
CC=golang-dev
https://golang.org/cl/6842081
---
 src/pkg/runtime/defs_netbsd.go      |  2 ++
 src/pkg/runtime/defs_netbsd_386.h   |  2 ++
 src/pkg/runtime/defs_netbsd_amd64.h |  2 ++
 src/pkg/runtime/mem_netbsd.c        |  4 +---
 src/pkg/runtime/sys_netbsd_386.s    |  9 ++++++++-
 src/pkg/runtime/sys_netbsd_amd64.s  | 12 +++++++++++-
 6 files changed, 26 insertions(+), 5 deletions(-)

diff --git a/src/pkg/runtime/defs_netbsd.go b/src/pkg/runtime/defs_netbsd.go
index 6c46bb2f29..53e061041e 100644
--- a/src/pkg/runtime/defs_netbsd.go
+++ b/src/pkg/runtime/defs_netbsd.go
@@ -37,6 +37,8 @@ const (
 	MAP_PRIVATE = C.MAP_PRIVATE
 	MAP_FIXED   = C.MAP_FIXED
 
+	MADV_FREE = C.MADV_FREE
+
 	SA_SIGINFO = C.SA_SIGINFO
 	SA_RESTART = C.SA_RESTART
 	SA_ONSTACK = C.SA_ONSTACK
diff --git a/src/pkg/runtime/defs_netbsd_386.h b/src/pkg/runtime/defs_netbsd_386.h
index 89b3ab4899..04c380e3f0 100644
--- a/src/pkg/runtime/defs_netbsd_386.h
+++ b/src/pkg/runtime/defs_netbsd_386.h
@@ -12,6 +12,8 @@ enum {
 	MAP_PRIVATE	= 0x2,
 	MAP_FIXED	= 0x10,
 
+	MADV_FREE	= 0x6,
+
 	SA_SIGINFO	= 0x40,
 	SA_RESTART	= 0x2,
 	SA_ONSTACK	= 0x1,
diff --git a/src/pkg/runtime/defs_netbsd_amd64.h b/src/pkg/runtime/defs_netbsd_amd64.h
index c6ee7d8c26..3d3f576d31 100644
--- a/src/pkg/runtime/defs_netbsd_amd64.h
+++ b/src/pkg/runtime/defs_netbsd_amd64.h
@@ -12,6 +12,8 @@ enum {
 	MAP_PRIVATE	= 0x2,
 	MAP_FIXED	= 0x10,
 
+	MADV_FREE	= 0x6,
+
 	SA_SIGINFO	= 0x40,
 	SA_RESTART	= 0x2,
 	SA_ONSTACK	= 0x1,
diff --git a/src/pkg/runtime/mem_netbsd.c b/src/pkg/runtime/mem_netbsd.c
index 34ff31d908..43fef40ba4 100644
--- a/src/pkg/runtime/mem_netbsd.c
+++ b/src/pkg/runtime/mem_netbsd.c
@@ -28,9 +28,7 @@ runtime·SysAlloc(uintptr n)
 void
 runtime·SysUnused(void *v, uintptr n)
 {
-	USED(v);
-	USED(n);
-	// TODO(rsc): call madvise MADV_DONTNEED
+	runtime·madvise(v, n, MADV_FREE);
 }
 
 void
diff --git a/src/pkg/runtime/sys_netbsd_386.s b/src/pkg/runtime/sys_netbsd_386.s
index c4bc80933a..9c88b14487 100644
--- a/src/pkg/runtime/sys_netbsd_386.s
+++ b/src/pkg/runtime/sys_netbsd_386.s
@@ -83,6 +83,13 @@ TEXT runtime·munmap(SB),7,$-4
 	MOVL	$0xf1, 0xf1		// crash
 	RET
 
+TEXT runtime·madvise(SB),7,$-4
+	MOVL	$75, AX			// sys_madvise
+	INT	$0x80
+	JAE	2(PC)
+	MOVL	$0xf1, 0xf1		// crash
+	RET
+
 TEXT runtime·setitimer(SB),7,$-4
 	MOVL	$425, AX		// sys_setitimer
 	INT	$0x80
@@ -180,7 +187,7 @@ TEXT runtime·sigtramp(SB),7,$44
 	CMPL	BX, $0
 	JNE	5(PC)
 	MOVL	signo+0(FP), BX
-	MOVL	BX, 0(SP)      
+	MOVL	BX, 0(SP)
 	CALL	runtime·badsignal(SB)
 	RET
 
diff --git a/src/pkg/runtime/sys_netbsd_amd64.s b/src/pkg/runtime/sys_netbsd_amd64.s
index 9fe1ebbc49..e00c727ccb 100644
--- a/src/pkg/runtime/sys_netbsd_amd64.s
+++ b/src/pkg/runtime/sys_netbsd_amd64.s
@@ -10,7 +10,6 @@
 
 // int32 lwp_create(void *context, uintptr flags, void *lwpid)
 TEXT runtime·lwp_create(SB),7,$0
-
 	MOVQ	context+0(FP), DI
 	MOVQ	flags+8(FP), SI
 	MOVQ	lwpid+16(FP), DX
@@ -248,6 +247,17 @@ TEXT runtime·munmap(SB),7,$0
 	MOVL	$0xf1, 0xf1		// crash
 	RET
 
+
+TEXT runtime·madvise(SB),7,$0
+	MOVQ	addr+0(FP), DI		// arg 1 - addr
+	MOVQ	len+8(FP), SI		// arg 2 - len
+	MOVQ	behav+16(FP), DX	// arg 3 - behav
+	MOVQ	$75, AX			// sys_madvise
+	SYSCALL
+	JCC	2(PC)
+	MOVL	$0xf1, 0xf1		// crash
+	RET
+
 TEXT runtime·sigaltstack(SB),7,$-8
 	MOVQ	new+8(SP), DI		// arg 1 - nss
 	MOVQ	old+16(SP), SI		// arg 2 - oss
-- 
2.48.1