runtime: use UMTX_OP_WAIT_UINT on FreeBSD

UMTX_OP_WAIT expects that the address points to a uintptr, but
the code in lock_futex.c uses a uint32.  UMTX_OP_WAIT_UINT is
just like UMTX_OP_WAIT, but the address points to a uint32.
This almost certainly makes no difference on a little-endian
system, but since the kernel supports it we should do the
right thing.  And, who knows, maybe it matters.

R=golang-dev, bradfitz, r, ality
CC=golang-dev
https://golang.org/cl/8699043

src/pkg/runtime/defs_freebsd.go

@@ -45,8 +45,8 @@ const (
 	SA_RESTART = C.SA_RESTART
 	SA_ONSTACK = C.SA_ONSTACK
 
-	UMTX_OP_WAIT = C.UMTX_OP_WAIT
-	UMTX_OP_WAKE = C.UMTX_OP_WAKE
+	UMTX_OP_WAIT_UINT = C.UMTX_OP_WAIT_UINT
+	UMTX_OP_WAKE      = C.UMTX_OP_WAKE
 
 	EINTR = C.EINTR
 

src/pkg/runtime/defs_freebsd_386.h

@@ -18,8 +18,8 @@ enum {
 	SA_RESTART	= 0x2,
 	SA_ONSTACK	= 0x1,
 
-	UMTX_OP_WAIT	= 0x2,
-	UMTX_OP_WAKE	= 0x3,
+	UMTX_OP_WAIT_UINT	= 0xb,
+	UMTX_OP_WAKE		= 0x3,
 
 	EINTR	= 0x4,
 

src/pkg/runtime/defs_freebsd_amd64.h

@@ -18,8 +18,8 @@ enum {
 	SA_RESTART	= 0x2,
 	SA_ONSTACK	= 0x1,
 
-	UMTX_OP_WAIT	= 0x2,
-	UMTX_OP_WAKE	= 0x3,
+	UMTX_OP_WAIT_UINT	= 0xb,
+	UMTX_OP_WAKE		= 0x3,
 
 	EINTR	= 0x4,
 

src/pkg/runtime/defs_freebsd_arm.h

@@ -18,8 +18,8 @@ enum {
 	SA_RESTART	= 0x2,
 	SA_ONSTACK	= 0x1,
 
-	UMTX_OP_WAIT	= 0x2,
-	UMTX_OP_WAKE	= 0x3,
+	UMTX_OP_WAIT_UINT	= 0xb,
+	UMTX_OP_WAKE		= 0x3,
 
 	EINTR	= 0x4,
 

src/pkg/runtime/os_freebsd.c

@@ -60,7 +60,7 @@ runtime·futexsleep(uint32 *addr, uint32 val, int64 ns)
 		tsp = &ts;
 	}
 
-	ret = runtime·sys_umtx_op(addr, UMTX_OP_WAIT, val, nil, tsp);
+	ret = runtime·sys_umtx_op(addr, UMTX_OP_WAIT_UINT, val, nil, tsp);
 	if(ret >= 0 || ret == -EINTR)
 		return;