libthread: Lion context routines

src/libthread/Darwin-x86_64-asm.s

@@ -0,0 +1,44 @@
+.text
+.align 8
+
+.globl	_libthread_getmcontext
+_libthread_getmcontext:
+	movq	$1, 0*8(%rdi)  // rax
+	movq	%rbx, 1*8(%rdi)
+	movq	%rcx, 2*8(%rdi)
+	movq	%rdx, 3*8(%rdi)
+	movq	%rsi, 4*8(%rdi)
+	movq	%rdi, 5*8(%rdi)
+	movq	%rbp, 6*8(%rdi)
+	movq	%rsp, 7*8(%rdi)
+	movq	%r8, 8*8(%rdi)
+	movq	%r9, 9*8(%rdi)
+	movq	%r10, 10*8(%rdi)
+	movq	%r11, 11*8(%rdi)
+	movq	%r12, 12*8(%rdi)
+	movq	%r13, 13*8(%rdi)
+	movq	%r14, 14*8(%rdi)
+	movq	%r15, 15*8(%rdi)
+	movq	$0, %rax
+	ret
+
+.globl	_libthread_setmcontext
+_libthread_setmcontext:
+	movq	0*8(%rdi), %rax
+	movq	1*8(%rdi), %rbx
+	movq	2*8(%rdi), %rcx
+	movq	3*8(%rdi), %rdx
+	movq	4*8(%rdi), %rsi
+	// %rdi later
+	movq	6*8(%rdi), %rbp
+	movq	7*8(%rdi), %rsp
+	movq	8*8(%rdi), %r8
+	movq	9*8(%rdi), %r9
+	movq	10*8(%rdi), %r10
+	movq	11*8(%rdi), %r11
+	movq	12*8(%rdi), %r12
+	movq	13*8(%rdi), %r13
+	movq	14*8(%rdi), %r14
+	movq	15*8(%rdi), %r15
+	movq	5*8(%rdi), %rdi
+	ret

src/libthread/Darwin-x86_64-swapcontext.c

@@ -0,0 +1,32 @@
+#include "threadimpl.h"
+
+void
+makecontext(ucontext_t *uc, void (*fn)(void), int argc, ...)
+{
+	uintptr *sp;
+	va_list arg;
+
+//fprint(2, "makecontext %d\n", argc);
+	if(argc != 2)
+		sysfatal("libthread: makecontext misused");
+	va_start(arg, argc);
+	uc->mc.di = va_arg(arg, uint);
+	uc->mc.si = va_arg(arg, uint);
+//fprint(2, "%ux %ux\n", uc->mc.di, uc->mc.si);
+	va_end(arg);
+
+	sp = (uintptr*)((char*)uc->uc_stack.ss_sp+uc->uc_stack.ss_size);
+	*--sp = 0;  // fn's return address
+	*--sp = (uintptr)fn;  // return address of setcontext
+	uc->mc.sp = (uintptr)sp;
+}
+
+int
+swapcontext(ucontext_t *oucp, ucontext_t *ucp)
+{
+	if(getcontext(oucp) == 0)
+		setcontext(ucp);
+	return 0;
+}
+
+

src/libthread/sysofiles.sh

@@ -34,5 +34,8 @@ arm-Linux)
 	# ARM doesn't supply them either.
 	echo Linux-arm-context.o Linux-arm-swapcontext.o
 	;;
+x86_64-Darwin)
+	echo Darwin-x86_64-asm.o Darwin-x86_64-swapcontext.o
+	;;
 esac
 

src/libthread/thread.c

@@ -86,6 +86,7 @@ threadstart(uint y, uint x)
 	_Thread *t;
 	ulong z;
 
+//print("threadstart\n");
 	z = (ulong)x << 16;	/* hide undefined 32-bit shift from 32-bit compilers */
 	z <<= 16;
 	z |= y;
@@ -317,7 +318,7 @@ procscheduler(Proc *p)
 
 	setproc(p);
 	_threaddebug("scheduler enter");
-/*	print("s %p\n", p); */
+//print("s %p\n", p);
 	lock(&p->lock);
 	for(;;){
 		if((t = p->pinthread) != nil){
@@ -354,6 +355,7 @@ procscheduler(Proc *p)
 		p->thread = t;
 		p->nswitch++;
 		_threaddebug("run %d (%s)", t->id, t->name);
+//print("run %p %p %p %p\n", t, *(uintptr*)(t->context.uc.mc.sp), t->context.uc.mc.di, t->context.uc.mc.si);
 		contextswitch(&p->schedcontext, &t->context);
 /*print("back in scheduler\n"); */
 		p->thread = nil;

src/libthread/threadimpl.h

@@ -24,7 +24,7 @@ extern	int		swapcontext(ucontext_t*, ucontext_t*);
 extern	void		makecontext(ucontext_t*, void(*)(), int, ...);
 #endif
 
-#if defined(__APPLE__) && !defined(__x86_64__)
+#if defined(__APPLE__)
 	/*
 	 * OS X before 10.5 (Leopard) does not provide
 	 * swapcontext nor makecontext, so we have to use our own.
@@ -40,6 +40,8 @@ extern	void		makecontext(ucontext_t*, void(*)(), int, ...);
 #	define makecontext libthread_makecontext
 #	if defined(__i386__)
 #		include "386-ucontext.h"
+#	elif defined(__x86_64__)
+#		include "x86_64-ucontext.h"
 #	elif defined(__power__)
 #		include "power-ucontext.h"
 #	else
@@ -108,7 +110,7 @@ struct Context
 	 * end of the ucontext_t.  Sigh.  We put some extra
 	 * scratch space here for them.
 	 */
-	uchar	buf[512];
+	uchar	buf[1024];
 #endif
 };
 

src/libthread/x86_64-ucontext.h

@@ -0,0 +1,43 @@
+#define	setcontext(u)	libthread_setmcontext(&(u)->mc)
+#define	getcontext(u)	libthread_getmcontext(&(u)->mc)
+typedef struct mcontext mcontext_t;
+typedef struct ucontext ucontext_t;
+
+struct mcontext
+{
+	uintptr	ax;
+	uintptr	bx;
+	uintptr cx;
+	uintptr dx;
+	uintptr si;
+	uintptr di;
+	uintptr	bp;
+	uintptr sp;
+	uintptr r8;
+	uintptr r9;
+	uintptr r10;
+	uintptr r11;
+	uintptr r12;
+	uintptr r13;
+	uintptr r14;
+	uintptr r15;
+/*
+// XXX: currently do not save vector registers or floating-point state
+*/
+};
+
+struct ucontext
+{
+	struct {
+		void *ss_sp;
+		uint ss_size;
+	} uc_stack;
+	sigset_t uc_sigmask;
+	mcontext_t mc;
+};
+
+void makecontext(ucontext_t*, void(*)(void), int, ...);
+int swapcontext(ucontext_t*, ucontext_t*);
+int libthread_getmcontext(mcontext_t*);
+void libthread_setmcontext(mcontext_t*);
+