if w.context != nil && file == fmt.Sprintf("zruntime_defs_%s_%s.go", w.context.GOOS, w.context.GOARCH) {
// Just enough to keep the api checker happy.
src := "package runtime; type (" +
- " maptype struct{}; _type struct{}; alg struct{};" +
- " mspan struct{}; m struct{}; mutex struct{}; slicetype struct{};" +
- " iface struct{}; eface struct{}; interfacetype struct{}; itab struct{};" +
- " mcache struct{}; sudog struct{}; g struct{};" +
- " hchan struct{}; chantype struct{}; waitq struct{};" +
- " note struct{}; wincallbackcontext struct{};" +
- " gobuf struct{}; funcval struct{}; _func struct{};" +
+ " _func struct{};" +
+ " _type struct{};" +
+ " alg struct{};" +
+ " chantype struct{};" +
+ " context struct{};" + // windows
+ " eface struct{};" +
+ " funcval struct{};" +
+ " g struct{};" +
+ " gobuf struct{};" +
+ " hchan struct{};" +
+ " iface struct{};" +
+ " interfacetype struct{};" +
+ " itab struct{};" +
+ " m struct{};" +
+ " maptype struct{};" +
+ " mcache struct{};" +
+ " mspan struct{};" +
+ " mutex struct{};" +
+ " note struct{};" +
+ " slicetype struct{};" +
+ " stkframe struct{};" +
+ " sudog struct{};" +
+ " waitq struct{};" +
+ " wincallbackcontext struct{};" +
"); " +
"const ( cb_max = 2000 )"
f, err = parser.ParseFile(fset, filename, src, 0)
// If all other goroutines exit, the program crashes.
func Goexit()
-// We assume that all architectures turn faults and the like
-// into apparent calls to runtime.sigpanic. If we see a "call"
-// to runtime.sigpanic, we do not back up the PC to find the
-// line number of the CALL instruction, because there is no CALL.
-var sigpanic byte
+// sigpanic is the C function sigpanic.
+// That is, unsafe.Pointer(&sigpanic) is the C function pointer for sigpanic.
+var sigpanic struct{}
// Caller reports file and line number information about function invocations on
// the calling goroutine's stack. The argument skip is the number of stack frames
// and what it called, so that we can see if it
// "called" sigpanic.
var rpc [2]uintptr
- if callers(int32(1+skip-1), &rpc[0], 2) < 2 {
+ if callers(1+skip-1, &rpc[0], 2) < 2 {
return
}
f := findfunc(rpc[1])
pc = rpc[1]
xpc := pc
g := findfunc(rpc[0])
+ // All architectures turn faults into apparent calls to sigpanic.
+ // If we see a call to sigpanic, we do not back up the PC to find
+ // the line number of the call instruction, because there is no call.
if xpc > f.entry && (g == nil || g.entry != uintptr(unsafe.Pointer(&sigpanic))) {
xpc--
}
if len(pc) == 0 {
return 0
}
- return int(callers(int32(skip), &pc[0], int32(len(pc))))
+ return callers(skip, &pc[0], len(pc))
}
-//go:noescape
-func callers(int32, *uintptr, int32) int32
-
-//go:noescape
-func gcallers(*g, int32, *uintptr, int32) int32
-
-//go:noescape
-func gentraceback(uintptr, uintptr, uintptr, *g, int32, *uintptr, int32, unsafe.Pointer, unsafe.Pointer, bool) int32
-
func getgoroot() string
// GOROOT returns the root of the Go tree.
ChildInfo child;
Defer *d;
Panic *p;
+ bool (*fn)(Stkframe*, void*);
if(gp->syscallstack != (uintptr)nil) {
sp = gp->syscallsp;
child.depth = 0;
if(!ScanStackByFrames)
runtime·throw("need frame info to dump stacks");
- runtime·gentraceback(pc, sp, lr, gp, 0, nil, 0x7fffffff, dumpframe, &child, false);
+ fn = dumpframe;
+ runtime·gentraceback(pc, sp, lr, gp, 0, nil, 0x7fffffff, &fn, &child, false);
// dump defer & panic records
for(d = gp->defer; d != nil; d = d->link) {
int32 n;
Stktop *stk;
uintptr sp, guard;
+ bool (*fn)(Stkframe*, void*);
switch(runtime·readgstatus(gp)) {
default:
USED(sp);
USED(stk);
USED(guard);
- runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, 0, nil, 0x7fffffff, scanframe, nil, false);
+ fn = scanframe;
+ runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, 0, nil, 0x7fffffff, &fn, nil, false);
} else {
n = 0;
while(stk) {
Stkframe frame;
uintptr i, n, off;
byte *base, bits, shift, *b;
+ bool (*cb)(Stkframe*, void*);
*mask = nil;
*len = 0;
// stack
frame.fn = nil;
frame.sp = (uintptr)p;
- runtime·gentraceback((uintptr)runtime·getcallerpc(&p), (uintptr)runtime·getcallersp(&p), 0, g, 0, nil, 1000, getgcmaskcb, &frame, false);
+ cb = getgcmaskcb;
+ runtime·gentraceback((uintptr)runtime·getcallerpc(&p), (uintptr)runtime·getcallersp(&p), 0, g, 0, nil, 1000, &cb, &frame, false);
if(frame.fn != nil) {
Func *f;
StackMap *stackmap;
// Called by malloc to record a profiled block.
func mProf_Malloc(p unsafe.Pointer, size uintptr) {
var stk [maxStack]uintptr
- nstk := callers(1, &stk[0], int32(len(stk)))
+ nstk := callers(1, &stk[0], len(stk))
lock(&proflock)
b := stkbucket(memProfile, size, stk[:nstk], true)
mp := b.mp()
var nstk int
var stk [maxStack]uintptr
if gp.m.curg == nil || gp.m.curg == gp {
- nstk = int(callers(int32(skip), &stk[0], int32(len(stk))))
+ nstk = callers(skip, &stk[0], len(stk))
} else {
- nstk = int(gcallers(gp.m.curg, int32(skip), &stk[0], int32(len(stk))))
+ nstk = gcallers(gp.m.curg, skip, &stk[0], len(stk))
}
lock(&proflock)
b := stkbucket(blockProfile, 0, stk[:nstk], true)
}
func saveg(pc, sp uintptr, gp *g, r *StackRecord) {
- n := gentraceback(pc, sp, 0, gp, 0, &r.Stack0[0], int32(len(r.Stack0)), nil, nil, false)
- if int(n) < len(r.Stack0) {
+ n := gentraceback(pc, sp, 0, gp, 0, &r.Stack0[0], len(r.Stack0), nil, nil, false)
+ if n < len(r.Stack0) {
r.Stack0[n] = 0
}
}
--- /dev/null
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+// contextPC returns the EIP (program counter) register from the context.
+func contextPC(r *context) uintptr { return uintptr(r.eip) }
+
+// contextSP returns the ESP (stack pointer) register from the context.
+func contextSP(r *context) uintptr { return uintptr(r.esp) }
--- /dev/null
+// Copyright 2014 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+// contextPC returns the RIP (program counter) register from the context.
+func contextPC(r *context) uintptr { return uintptr(r.rip) }
+
+// contextSP returns the RSP (stack pointer) register from the context.
+func contextSP(r *context) uintptr { return uintptr(r.rsp) }
uintptr arglen; // number of bytes at argp
};
-int32 runtime·gentraceback(uintptr, uintptr, uintptr, G*, int32, uintptr*, int32, bool(*)(Stkframe*, void*), void*, bool);
+intgo runtime·gentraceback(uintptr, uintptr, uintptr, G*, intgo, uintptr*, intgo, bool(**)(Stkframe*, void*), void*, bool);
void runtime·traceback(uintptr pc, uintptr sp, uintptr lr, G* gp);
void runtime·tracebackothers(G*);
bool runtime·haszeroargs(uintptr pc);
void runtime·entersyscallblock_m(void);
G* runtime·newproc1(FuncVal*, byte*, int32, int32, void*);
bool runtime·sigsend(int32 sig);
-int32 runtime·callers(int32, uintptr*, int32);
-int32 runtime·gcallers(G*, int32, uintptr*, int32);
+intgo runtime·callers(intgo, uintptr*, intgo);
+intgo runtime·gcallers(G*, intgo, uintptr*, intgo);
int64 runtime·nanotime(void); // monotonic time
int64 runtime·unixnanotime(void); // real time, can skip
void runtime·dopanic(int32);
void runtime·usleep(uint32);
int64 runtime·cputicks(void);
int64 runtime·tickspersecond(void);
-void runtime·blockevent(int64, int32);
+void runtime·blockevent(int64, intgo);
G* runtime·netpoll(bool);
void runtime·netpollinit(void);
int32 runtime·netpollopen(uintptr, PollDesc*);
Func *f;
FuncVal *fn;
StackMap *stackmap;
+ bool (*cb)(Stkframe*, void*);
if(gp->stackbase == 0)
runtime·throw("stackbase == 0");
// Check that each frame is copyable. As a side effect,
// count the frames.
- runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, 0, nil, 0x7fffffff, checkframecopy, &cinfo, false);
+ cb = checkframecopy;
+ runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, 0, nil, 0x7fffffff, &cb, &cinfo, false);
if(StackDebug >= 1 && cinfo.frames != -1)
runtime·printf("copystack: %d copyable frames\n", cinfo.frames);
// adjust inargs and outargs
if(frame->arglen != 0) {
stackmap = runtime·funcdata(f, FUNCDATA_ArgsPointerMaps);
- if(stackmap == nil)
+ if(stackmap == nil) {
+ runtime·printf("size %d\n", (int32)frame->arglen);
runtime·throw("no arg info");
+ }
bv = runtime·stackmapdata(stackmap, pcdata);
if(StackDebug >= 3)
runtime·printf(" args\n");
AdjustInfo adjinfo;
Stktop *oldtop, *newtop;
uint32 oldstatus;
+ bool (*cb)(Stkframe*, void*);
if(gp->syscallstack != 0)
runtime·throw("can't handle stack copy in syscall yet");
adjinfo.oldstk = oldstk;
adjinfo.oldbase = oldbase;
adjinfo.delta = newbase - oldbase;
- runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, 0, nil, nframes, adjustframe, &adjinfo, false);
+ cb = adjustframe;
+ runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, 0, nil, nframes, &cb, &adjinfo, false);
// adjust other miscellaneous things that have pointers into stacks.
adjustctxt(gp, &adjinfo);
// each function.
const ptrSize = 4 << (^uintptr(0) >> 63) // unsafe.Sizeof(uintptr(0)) but an ideal const
+const regSize = 4 << (^uintreg(0) >> 63) // unsafe.Sizeof(uintreg(0)) but an ideal const
//go:noescape
func racereadpc(addr unsafe.Pointer, callpc, pc uintptr)
func exitsyscall()
func goroutineheader(gp *g)
-func traceback(pc, sp, lr uintptr, gp *g)
func tracebackothers(gp *g)
func cgocallback(fn, frame unsafe.Pointer, framesize uintptr)
//go:noescape
func open(name *byte, mode, perm int32) int32
+
+//go:noescape
+func gotraceback(*bool) int32
+
+func funcname(*_func) *byte
+
+func gofuncname(f *_func) string {
+ return gostringnocopy(funcname(f))
+}
+
+const _NoArgs = ^uintptr(0)
+
+var newproc, deferproc, lessstack struct{} // C/assembly functions
+
+func funcspdelta(*_func, uintptr) int32 // symtab.c
+func funcarglen(*_func, uintptr) int32 // symtab.c
+const _ArgsSizeUnknown = -0x80000000 // funcdata.h
+func topofstack(*_func) bool // proc.c
--- /dev/null
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+// The code in this file implements stack trace walking for all architectures.
+// The most important fact about a given architecture is whether it uses a link register.
+// On systems with link registers, the prologue for a non-leaf function stores the
+// incoming value of LR at the bottom of the newly allocated stack frame.
+// On systems without link registers, the architecture pushes a return PC during
+// the call instruction, so the return PC ends up above the stack frame.
+// In this file, the return PC is always called LR, no matter how it was found.
+//
+// To date, the opposite of a link register architecture is an x86 architecture.
+// This code may need to change if some other kind of non-link-register
+// architecture comes along.
+//
+// The other important fact is the size of a pointer: on 32-bit systems the LR
+// takes up only 4 bytes on the stack, while on 64-bit systems it takes up 8 bytes.
+// Typically this is ptrSize.
+//
+// As an exception, amd64p32 has ptrSize == 4 but the CALL instruction still
+// stores an 8-byte return PC onto the stack. To accommodate this, we use regSize
+// as the size of the architecture-pushed return PC.
+//
+// usesLR is defined below. ptrSize and regSize are defined in stubs.go.
+
+const usesLR = GOARCH != "amd64" && GOARCH != "amd64p32" && GOARCH != "386"
+
+// jmpdeferPC is the PC at the beginning of the jmpdefer assembly function.
+// The traceback needs to recognize it on link register architectures.
+var jmpdeferPC uintptr
+
+func init() {
+ f := jmpdefer
+ jmpdeferPC = **(**uintptr)(unsafe.Pointer(&f))
+}
+
+// System-specific hook. See traceback_windows.go
+var systraceback func(*_func, *stkframe, *g, bool, func(*stkframe, unsafe.Pointer) bool, unsafe.Pointer) (changed, aborted bool)
+
+// Generic traceback. Handles runtime stack prints (pcbuf == nil),
+// the runtime.Callers function (pcbuf != nil), as well as the garbage
+// collector (callback != nil). A little clunky to merge these, but avoids
+// duplicating the code and all its subtlety.
+func gentraceback(pc0 uintptr, sp0 uintptr, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max int, callback func(*stkframe, unsafe.Pointer) bool, v unsafe.Pointer, printall bool) int {
+ g := getg()
+ gotraceback := gotraceback(nil)
+ if pc0 == ^uintptr(0) && sp0 == ^uintptr(0) { // Signal to fetch saved values from gp.
+ if gp.syscallstack != 0 {
+ pc0 = gp.syscallpc
+ sp0 = gp.syscallsp
+ if usesLR {
+ lr0 = 0
+ }
+ } else {
+ pc0 = gp.sched.pc
+ sp0 = gp.sched.sp
+ if usesLR {
+ lr0 = gp.sched.lr
+ }
+ }
+ }
+
+ nprint := 0
+ var frame stkframe
+ frame.pc = pc0
+ frame.sp = sp0
+ if usesLR {
+ frame.lr = lr0
+ }
+ waspanic := false
+ wasnewproc := false
+ printing := pcbuf == nil && callback == nil
+ panic := gp._panic
+ _defer := gp._defer
+
+ for _defer != nil && uintptr(_defer.argp) == _NoArgs {
+ _defer = _defer.link
+ }
+ for panic != nil && panic._defer == nil {
+ panic = panic.link
+ }
+
+ // If the PC is zero, it's likely a nil function call.
+ // Start in the caller's frame.
+ if frame.pc == 0 {
+ if usesLR {
+ frame.pc = *(*uintptr)(unsafe.Pointer(frame.sp))
+ frame.lr = 0
+ } else {
+ frame.pc = uintptr(*(*uintreg)(unsafe.Pointer(frame.sp)))
+ frame.sp += regSize
+ }
+ }
+
+ f := findfunc(frame.pc)
+ if f == nil {
+ if callback != nil {
+ print("runtime: unknown pc ", hex(frame.pc), "\n")
+ gothrow("unknown pc")
+ }
+ return 0
+ }
+ frame.fn = f
+
+ n := 0
+ stk := (*stktop)(unsafe.Pointer(gp.stackbase))
+ for n < max {
+ // Typically:
+ // pc is the PC of the running function.
+ // sp is the stack pointer at that program counter.
+ // fp is the frame pointer (caller's stack pointer) at that program counter, or nil if unknown.
+ // stk is the stack containing sp.
+ // The caller's program counter is lr, unless lr is zero, in which case it is *(uintptr*)sp.
+ if frame.pc == uintptr(unsafe.Pointer(&lessstack)) {
+ // Hit top of stack segment. Unwind to next segment.
+ frame.pc = stk.gobuf.pc
+ frame.sp = stk.gobuf.sp
+ frame.lr = 0
+ frame.fp = 0
+ if printing && showframe(nil, gp) {
+ print("----- stack segment boundary -----\n")
+ }
+ stk = (*stktop)(unsafe.Pointer(stk.stackbase))
+ f = findfunc(frame.pc)
+ if f == nil {
+ print("runtime: unknown pc ", hex(frame.pc), " after stack split\n")
+ if callback != nil {
+ gothrow("unknown pc")
+ }
+ }
+ frame.fn = f
+ continue
+ }
+ f = frame.fn
+
+ // Hook for handling Windows exception handlers. See traceback_windows.go.
+ if systraceback != nil {
+ changed, aborted := systraceback(f, (*stkframe)(noescape(unsafe.Pointer(&frame))), gp, printing, callback, v)
+ if aborted {
+ return n
+ }
+ if changed {
+ continue
+ }
+ }
+
+ // Found an actual function.
+ // Derive frame pointer and link register.
+ if frame.fp == 0 {
+ frame.fp = frame.sp + uintptr(funcspdelta(f, frame.pc))
+ if !usesLR {
+ // On x86, call instruction pushes return PC before entering new function.
+ frame.fp += regSize
+ }
+ }
+ var flr *_func
+ if topofstack(f) {
+ frame.lr = 0
+ flr = nil
+ } else if usesLR && f.entry == jmpdeferPC {
+ // jmpdefer modifies SP/LR/PC non-atomically.
+ // If a profiling interrupt arrives during jmpdefer,
+ // the stack unwind may see a mismatched register set
+ // and get confused. Stop if we see PC within jmpdefer
+ // to avoid that confusion.
+ // See golang.org/issue/8153.
+ if callback != nil {
+ gothrow("traceback_arm: found jmpdefer when tracing with callback")
+ }
+ frame.lr = 0
+ } else {
+ if usesLR {
+ if n == 0 && frame.sp < frame.fp || frame.lr == 0 {
+ frame.lr = *(*uintptr)(unsafe.Pointer(frame.sp))
+ }
+ } else {
+ if frame.lr == 0 {
+ frame.lr = uintptr(*(*uintreg)(unsafe.Pointer(frame.fp - regSize)))
+ }
+ }
+ flr = findfunc(frame.lr)
+ if flr == nil {
+ // This happens if you get a profiling interrupt at just the wrong time.
+ // In that context it is okay to stop early.
+ // But if callback is set, we're doing a garbage collection and must
+ // get everything, so crash loudly.
+ if callback != nil {
+ print("runtime: unexpected return pc for ", gofuncname(f), " called from ", hex(frame.lr), "\n")
+ gothrow("unknown caller pc")
+ }
+ }
+ }
+
+ frame.varp = frame.fp
+ if !usesLR {
+ // On x86, call instruction pushes return PC before entering new function.
+ frame.varp -= regSize
+ }
+
+ // Derive size of arguments.
+ // Most functions have a fixed-size argument block,
+ // so we can use metadata about the function f.
+ // Not all, though: there are some variadic functions
+ // in package runtime and reflect, and for those we use call-specific
+ // metadata recorded by f's caller.
+ if callback != nil || printing {
+ frame.argp = frame.fp
+ if usesLR {
+ frame.argp += ptrSize
+ }
+ if f.args != _ArgsSizeUnknown {
+ frame.arglen = uintptr(f.args)
+ } else if flr == nil {
+ frame.arglen = 0
+ } else if frame.lr == uintptr(unsafe.Pointer(&lessstack)) {
+ frame.arglen = uintptr(stk.argsize)
+ } else {
+ i := funcarglen(flr, frame.lr)
+ if i >= 0 {
+ frame.arglen = uintptr(i)
+ } else {
+ var tmp string
+ if flr != nil {
+ tmp = gofuncname(flr)
+ } else {
+ tmp = "?"
+ }
+ print("runtime: unknown argument frame size for ", gofuncname(f), " called from ", hex(frame.lr), " [", tmp, "]\n")
+ if callback != nil {
+ gothrow("invalid stack")
+ }
+ frame.arglen = 0
+ }
+ }
+ }
+
+ // Determine function SP where deferproc would find its arguments.
+ var sparg uintptr
+ if usesLR {
+ // On link register architectures, that's the standard bottom-of-stack plus 1 word
+ // for the saved LR. If the previous frame was a direct call to newproc/deferproc,
+ // however, the SP is three words lower than normal.
+ // If the function has no frame at all - perhaps it just started, or perhaps
+ // it is a leaf with no local variables - then we cannot possibly find its
+ // SP in a defer, and we might confuse its SP for its caller's SP, so
+ // leave sparg=0 in that case.
+ if frame.fp != frame.sp {
+ sparg = frame.sp + regSize
+ if wasnewproc {
+ sparg += 3 * regSize
+ }
+ }
+ } else {
+ // On x86 that's the standard bottom-of-stack, so SP exactly.
+ // If the previous frame was a direct call to newproc/deferproc, however,
+ // the SP is two words lower than normal.
+ sparg = frame.sp
+ if wasnewproc {
+ sparg += 2 * ptrSize
+ }
+ }
+
+ // Determine frame's 'continuation PC', where it can continue.
+ // Normally this is the return address on the stack, but if sigpanic
+ // is immediately below this function on the stack, then the frame
+ // stopped executing due to a trap, and frame.pc is probably not
+ // a safe point for looking up liveness information. In this panicking case,
+ // the function either doesn't return at all (if it has no defers or if the
+ // defers do not recover) or it returns from one of the calls to
+ // deferproc a second time (if the corresponding deferred func recovers).
+ // It suffices to assume that the most recent deferproc is the one that
+ // returns; everything live at earlier deferprocs is still live at that one.
+ frame.continpc = frame.pc
+ if waspanic {
+ if panic != nil && panic._defer.argp == sparg {
+ frame.continpc = panic._defer.pc
+ } else if _defer != nil && _defer.argp == sparg {
+ frame.continpc = _defer.pc
+ } else {
+ frame.continpc = 0
+ }
+ }
+
+ // Unwind our local panic & defer stacks past this frame.
+ for panic != nil && (panic._defer == nil || panic._defer.argp == sparg || panic._defer.argp == _NoArgs) {
+ panic = panic.link
+ }
+ for _defer != nil && (_defer.argp == sparg || _defer.argp == _NoArgs) {
+ _defer = _defer.link
+ }
+
+ if skip > 0 {
+ skip--
+ goto skipped
+ }
+
+ if pcbuf != nil {
+ (*[1 << 20]uintptr)(unsafe.Pointer(pcbuf))[n] = frame.pc
+ }
+ if callback != nil {
+ if !callback((*stkframe)(noescape(unsafe.Pointer(&frame))), v) {
+ return n
+ }
+ }
+ if printing {
+ if printall || showframe(f, gp) {
+ // Print during crash.
+ // main(0x1, 0x2, 0x3)
+ // /home/rsc/go/src/runtime/x.go:23 +0xf
+ //
+ tracepc := frame.pc // back up to CALL instruction for funcline.
+ if n > 0 && frame.pc > f.entry && !waspanic {
+ tracepc--
+ }
+ print(gofuncname(f), "(")
+ argp := (*[100]uintptr)(unsafe.Pointer(frame.argp))
+ for i := uintptr(0); i < frame.arglen/ptrSize; i++ {
+ if i >= 10 {
+ print(", ...")
+ break
+ }
+ if i != 0 {
+ print(", ")
+ }
+ print(hex(argp[i]))
+ }
+ print(")\n")
+ var file string
+ line := funcline(f, tracepc, &file)
+ print("\t", file, ":", line)
+ if frame.pc > f.entry {
+ print(" +", hex(frame.pc-f.entry))
+ }
+ if g.m.throwing > 0 && gp == g.m.curg || gotraceback >= 2 {
+ print(" fp=", hex(frame.fp), " sp=", hex(frame.sp))
+ }
+ print("\n")
+ nprint++
+ }
+ }
+ n++
+
+ skipped:
+ waspanic = f.entry == uintptr(unsafe.Pointer(&sigpanic))
+ wasnewproc = f.entry == uintptr(unsafe.Pointer(&newproc)) || f.entry == uintptr(unsafe.Pointer(&deferproc))
+
+ // Do not unwind past the bottom of the stack.
+ if flr == nil {
+ break
+ }
+
+ // Unwind to next frame.
+ frame.fn = flr
+ frame.pc = frame.lr
+ frame.lr = 0
+ frame.sp = frame.fp
+ frame.fp = 0
+
+ // On link register architectures, sighandler saves the LR on stack
+ // before faking a call to sigpanic.
+ if usesLR && waspanic {
+ x := *(*uintptr)(unsafe.Pointer(frame.sp))
+ frame.sp += ptrSize
+ f = findfunc(frame.pc)
+ frame.fn = f
+ if f == nil {
+ frame.pc = x
+ } else if f.frame == 0 {
+ frame.lr = x
+ }
+ }
+ }
+
+ if pcbuf == nil && callback == nil {
+ n = nprint
+ }
+
+ // If callback != nil, we're being called to gather stack information during
+ // garbage collection or stack growth. In that context, require that we used
+ // up the entire defer stack. If not, then there is a bug somewhere and the
+ // garbage collection or stack growth may not have seen the correct picture
+ // of the stack. Crash now instead of silently executing the garbage collection
+ // or stack copy incorrectly and setting up for a mysterious crash later.
+ //
+ // Note that panic != nil is okay here: there can be leftover panics,
+ // because the defers on the panic stack do not nest in frame order as
+ // they do on the defer stack. If you have:
+ //
+ // frame 1 defers d1
+ // frame 2 defers d2
+ // frame 3 defers d3
+ // frame 4 panics
+ // frame 4's panic starts running defers
+ // frame 5, running d3, defers d4
+ // frame 5 panics
+ // frame 5's panic starts running defers
+ // frame 6, running d4, garbage collects
+ // frame 6, running d2, garbage collects
+ //
+ // During the execution of d4, the panic stack is d4 -> d3, which
+ // is nested properly, and we'll treat frame 3 as resumable, because we
+ // can find d3. (And in fact frame 3 is resumable. If d4 recovers
+ // and frame 5 continues running, d3, d3 can recover and we'll
+ // resume execution in (returning from) frame 3.)
+ //
+ // During the execution of d2, however, the panic stack is d2 -> d3,
+ // which is inverted. The scan will match d2 to frame 2 but having
+ // d2 on the stack until then means it will not match d3 to frame 3.
+ // This is okay: if we're running d2, then all the defers after d2 have
+ // completed and their corresponding frames are dead. Not finding d3
+ // for frame 3 means we'll set frame 3's continpc == 0, which is correct
+ // (frame 3 is dead). At the end of the walk the panic stack can thus
+ // contain defers (d3 in this case) for dead frames. The inversion here
+ // always indicates a dead frame, and the effect of the inversion on the
+ // scan is to hide those dead frames, so the scan is still okay:
+ // what's left on the panic stack are exactly (and only) the dead frames.
+ //
+ // We require callback != nil here because only when callback != nil
+ // do we know that gentraceback is being called in a "must be correct"
+ // context as opposed to a "best effort" context. The tracebacks with
+ // callbacks only happen when everything is stopped nicely.
+ // At other times, such as when gathering a stack for a profiling signal
+ // or when printing a traceback during a crash, everything may not be
+ // stopped nicely, and the stack walk may not be able to complete.
+ // It's okay in those situations not to use up the entire defer stack:
+ // incomplete information then is still better than nothing.
+ if callback != nil && n < max && _defer != nil {
+ if _defer != nil {
+ print("runtime: g", gp.goid, ": leftover defer argp=", hex(_defer.argp), " pc=", hex(_defer.pc), "\n")
+ }
+ if panic != nil {
+ print("runtime: g", gp.goid, ": leftover panic argp=", hex(panic._defer.argp), " pc=", hex(panic._defer.pc), "\n")
+ }
+ for _defer = gp._defer; _defer != nil; _defer = _defer.link {
+ print("\tdefer ", _defer, " argp=", hex(_defer.argp), " pc=", hex(_defer.pc), "\n")
+ }
+ for panic = gp._panic; panic != nil; panic = panic.link {
+ print("\tpanic ", panic, " defer ", panic._defer)
+ if panic._defer != nil {
+ print(" argp=", hex(panic._defer.argp), " pc=", hex(panic._defer.pc))
+ }
+ print("\n")
+ }
+ gothrow("traceback has leftover defers or panics")
+ }
+
+ return n
+}
+
+func showframe(*_func, *g) bool
+
+func printcreatedby(gp *g) {
+ // Show what created goroutine, except main goroutine (goid 1).
+ pc := gp.gopc
+ f := findfunc(pc)
+ if f != nil && showframe(f, gp) && gp.goid != 1 {
+ print("created by ", gofuncname(f), "\n")
+ tracepc := pc // back up to CALL instruction for funcline.
+ if pc > f.entry {
+ tracepc -= _PCQuantum
+ }
+ var file string
+ line := funcline(f, tracepc, &file)
+ print("\t", file, ":", line)
+ if pc > f.entry {
+ print(" +", hex(pc-f.entry))
+ }
+ print("\n")
+ }
+}
+
+func traceback(pc uintptr, sp uintptr, lr uintptr, gp *g) {
+ var n int
+ if readgstatus(gp)&^_Gscan == _Gsyscall {
+ // Override signal registers if blocked in system call.
+ pc = gp.syscallpc
+ sp = gp.syscallsp
+ }
+ // Print traceback. By default, omits runtime frames.
+ // If that means we print nothing at all, repeat forcing all frames printed.
+ n = gentraceback(pc, sp, 0, gp, 0, nil, _TracebackMaxFrames, nil, nil, false)
+ if n == 0 {
+ n = gentraceback(pc, sp, 0, gp, 0, nil, _TracebackMaxFrames, nil, nil, true)
+ }
+ if n == _TracebackMaxFrames {
+ print("...additional frames elided...\n")
+ }
+ printcreatedby(gp)
+}
+
+func callers(skip int, pcbuf *uintptr, m int) int {
+ sp := getcallersp(unsafe.Pointer(&skip))
+ pc := uintptr(getcallerpc(unsafe.Pointer(&skip)))
+ return gentraceback(pc, sp, 0, getg(), skip, pcbuf, m, nil, nil, false)
+}
+
+func gcallers(gp *g, skip int, pcbuf *uintptr, m int) int {
+ return gentraceback(^uintptr(0), ^uintptr(0), 0, gp, skip, pcbuf, m, nil, nil, false)
+}
+++ /dev/null
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-#include "runtime.h"
-#include "arch_GOARCH.h"
-#include "malloc.h"
-#include "funcdata.h"
-
-void runtime·sigpanic(void);
-void runtime·newproc(void);
-void runtime·deferproc(void);
-
-int32
-runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip, uintptr *pcbuf, int32 max, bool (*callback)(Stkframe*, void*), void *v, bool printall)
-{
- int32 i, n, nprint, line, gotraceback;
- uintptr x, tracepc, sparg;
- bool waspanic, wasnewproc, printing;
- Func *f, *flr;
- Stkframe frame;
- Stktop *stk;
- String file;
- Panic *panic;
- Defer *defer;
-
- gotraceback = runtime·gotraceback(nil);
-
- if(pc0 == ~(uintptr)0 && sp0 == ~(uintptr)0) { // Signal to fetch saved values from gp.
- if(gp->syscallstack != (uintptr)nil) {
- pc0 = gp->syscallpc;
- sp0 = gp->syscallsp;
- lr0 = 0;
- } else {
- pc0 = gp->sched.pc;
- sp0 = gp->sched.sp;
- lr0 = gp->sched.lr;
- }
- }
-
- nprint = 0;
- runtime·memclr((byte*)&frame, sizeof frame);
- frame.pc = pc0;
- frame.lr = lr0;
- frame.sp = sp0;
- waspanic = false;
- wasnewproc = false;
- printing = pcbuf==nil && callback==nil;
-
- panic = gp->panic;
- defer = gp->defer;
-
- while(defer != nil && defer->argp == NoArgs)
- defer = defer->link;
- while(panic != nil && panic->defer == nil)
- panic = panic->link;
-
- // If the PC is zero, it's likely a nil function call.
- // Start in the caller's frame.
- if(frame.pc == 0) {
- frame.pc = frame.lr;
- frame.lr = 0;
- }
-
- f = runtime·findfunc(frame.pc);
- if(f == nil) {
- if(callback != nil) {
- runtime·printf("runtime: unknown pc %p\n", frame.pc);
- runtime·throw("unknown pc");
- }
- return 0;
- }
- frame.fn = f;
-
- n = 0;
- stk = (Stktop*)gp->stackbase;
- while(n < max) {
- // Typically:
- // pc is the PC of the running function.
- // sp is the stack pointer at that program counter.
- // fp is the frame pointer (caller's stack pointer) at that program counter, or nil if unknown.
- // stk is the stack containing sp.
- // The caller's program counter is lr, unless lr is zero, in which case it is *(uintptr*)sp.
-
- if(frame.pc == (uintptr)runtime·lessstack) {
- // Hit top of stack segment. Unwind to next segment.
- frame.pc = stk->gobuf.pc;
- frame.sp = stk->gobuf.sp;
- frame.lr = 0;
- frame.fp = 0;
- if(printing && runtime·showframe(nil, gp))
- runtime·printf("----- stack segment boundary -----\n");
- stk = (Stktop*)stk->stackbase;
-
- f = runtime·findfunc(frame.pc);
- if(f == nil) {
- runtime·printf("runtime: unknown pc %p after stack split\n", frame.pc);
- if(callback != nil)
- runtime·throw("unknown pc");
- }
- frame.fn = f;
- continue;
- }
- f = frame.fn;
-
- // Found an actual function.
- // Derive frame pointer and link register.
- if(frame.fp == 0)
- frame.fp = frame.sp + runtime·funcspdelta(f, frame.pc);
- if(runtime·topofstack(f)) {
- frame.lr = 0;
- flr = nil;
- } else if(f->entry == (uintptr)runtime·jmpdefer) {
- // jmpdefer modifies SP/LR/PC non-atomically.
- // If a profiling interrupt arrives during jmpdefer,
- // the stack unwind may see a mismatched register set
- // and get confused. Stop if we see PC within jmpdefer
- // to avoid that confusion.
- // See golang.org/issue/8153.
- // This check can be deleted if jmpdefer is changed
- // to restore all three atomically using pop.
- if(callback != nil)
- runtime·throw("traceback_arm: found jmpdefer when tracing with callback");
- frame.lr = 0;
- flr = nil;
- } else {
- if((n == 0 && frame.sp < frame.fp) || frame.lr == 0)
- frame.lr = *(uintptr*)frame.sp;
- flr = runtime·findfunc(frame.lr);
- if(flr == nil) {
- // This happens if you get a profiling interrupt at just the wrong time.
- // In that context it is okay to stop early.
- // But if callback is set, we're doing a garbage collection and must
- // get everything, so crash loudly.
- if(callback != nil) {
- runtime·printf("runtime: unexpected return pc for %s called from %p\n", runtime·funcname(f), frame.lr);
- runtime·throw("unknown caller pc");
- }
- }
- }
-
- frame.varp = frame.fp;
-
- // Derive size of arguments.
- // Most functions have a fixed-size argument block,
- // so we can use metadata about the function f.
- // Not all, though: there are some variadic functions
- // in package runtime and reflect, and for those we use call-specific
- // metadata recorded by f's caller.
- if(callback != nil || printing) {
- frame.argp = frame.fp + sizeof(uintptr);
- if(f->args != ArgsSizeUnknown)
- frame.arglen = f->args;
- else if(flr == nil)
- frame.arglen = 0;
- else if(frame.lr == (uintptr)runtime·lessstack)
- frame.arglen = stk->argsize;
- else if((i = runtime·funcarglen(flr, frame.lr)) >= 0)
- frame.arglen = i;
- else {
- runtime·printf("runtime: unknown argument frame size for %s called from %p [%s]\n",
- runtime·funcname(f), frame.lr, flr ? runtime·funcname(flr) : "?");
- if(callback != nil)
- runtime·throw("invalid stack");
- frame.arglen = 0;
- }
- }
-
- // Determine function SP where deferproc would find its arguments.
- // On ARM that's just the standard bottom-of-stack plus 1 word for
- // the saved LR. If the previous frame was a direct call to newproc/deferproc,
- // however, the SP is three words lower than normal.
- // If the function has no frame at all - perhaps it just started, or perhaps
- // it is a leaf with no local variables - then we cannot possibly find its
- // SP in a defer, and we might confuse its SP for its caller's SP, so
- // set sparg=0 in that case.
- sparg = 0;
- if(frame.fp != frame.sp) {
- sparg = frame.sp + sizeof(uintreg);
- if(wasnewproc)
- sparg += 3*sizeof(uintreg);
- }
-
- // Determine frame's 'continuation PC', where it can continue.
- // Normally this is the return address on the stack, but if sigpanic
- // is immediately below this function on the stack, then the frame
- // stopped executing due to a trap, and frame.pc is probably not
- // a safe point for looking up liveness information. In this panicking case,
- // the function either doesn't return at all (if it has no defers or if the
- // defers do not recover) or it returns from one of the calls to
- // deferproc a second time (if the corresponding deferred func recovers).
- // It suffices to assume that the most recent deferproc is the one that
- // returns; everything live at earlier deferprocs is still live at that one.
- frame.continpc = frame.pc;
- if(waspanic) {
- if(panic != nil && panic->defer->argp == sparg)
- frame.continpc = (uintptr)panic->defer->pc;
- else if(defer != nil && defer->argp == sparg)
- frame.continpc = (uintptr)defer->pc;
- else
- frame.continpc = 0;
- }
-
- // Unwind our local panic & defer stacks past this frame.
- while(panic != nil && (panic->defer == nil || panic->defer->argp == sparg || panic->defer->argp == NoArgs))
- panic = panic->link;
- while(defer != nil && (defer->argp == sparg || defer->argp == NoArgs))
- defer = defer->link;
-
- if(skip > 0) {
- skip--;
- goto skipped;
- }
-
- if(pcbuf != nil)
- pcbuf[n] = frame.pc;
- if(callback != nil) {
- if(!callback(&frame, v))
- return n;
- }
- if(printing) {
- if(printall || runtime·showframe(f, gp)) {
- // Print during crash.
- // main(0x1, 0x2, 0x3)
- // /home/rsc/go/src/runtime/x.go:23 +0xf
- tracepc = frame.pc; // back up to CALL instruction for funcline.
- if(n > 0 && frame.pc > f->entry && !waspanic)
- tracepc -= sizeof(uintptr);
- runtime·printf("%s(", runtime·funcname(f));
- for(i = 0; i < frame.arglen/sizeof(uintptr); i++) {
- if(i >= 10) {
- runtime·prints(", ...");
- break;
- }
- if(i != 0)
- runtime·prints(", ");
- runtime·printhex(((uintptr*)frame.argp)[i]);
- }
- runtime·prints(")\n");
- line = runtime·funcline(f, tracepc, &file);
- runtime·printf("\t%S:%d", file, line);
- if(frame.pc > f->entry)
- runtime·printf(" +%p", (uintptr)(frame.pc - f->entry));
- if(g->m->throwing > 0 && gp == g->m->curg || gotraceback >= 2)
- runtime·printf(" fp=%p sp=%p", frame.fp, frame.sp);
- runtime·printf("\n");
- nprint++;
- }
- }
- n++;
-
- skipped:
- waspanic = f->entry == (uintptr)runtime·sigpanic;
- wasnewproc = f->entry == (uintptr)runtime·newproc || f->entry == (uintptr)runtime·deferproc;
-
- // Do not unwind past the bottom of the stack.
- if(flr == nil)
- break;
-
- // Unwind to next frame.
- frame.pc = frame.lr;
- frame.fn = flr;
- frame.lr = 0;
- frame.sp = frame.fp;
- frame.fp = 0;
-
- // sighandler saves the lr on stack before faking a call to sigpanic
- if(waspanic) {
- x = *(uintptr*)frame.sp;
- frame.sp += 4;
- frame.fn = f = runtime·findfunc(frame.pc);
- if(f == nil)
- frame.pc = x;
- else if(f->frame == 0)
- frame.lr = x;
- }
- }
-
- if(pcbuf == nil && callback == nil)
- n = nprint;
-
- // For rationale, see long comment in traceback_x86.c.
- if(callback != nil && n < max && defer != nil) {
- if(defer != nil)
- runtime·printf("runtime: g%D: leftover defer argp=%p pc=%p\n", gp->goid, defer->argp, defer->pc);
- if(panic != nil)
- runtime·printf("runtime: g%D: leftover panic argp=%p pc=%p\n", gp->goid, panic->defer->argp, panic->defer->pc);
- for(defer = gp->defer; defer != nil; defer = defer->link)
- runtime·printf("\tdefer %p argp=%p pc=%p\n", defer, defer->argp, defer->pc);
- for(panic = gp->panic; panic != nil; panic = panic->link) {
- runtime·printf("\tpanic %p defer %p", panic, panic->defer);
- if(panic->defer != nil)
- runtime·printf(" argp=%p pc=%p", panic->defer->argp, panic->defer->pc);
- runtime·printf("\n");
- }
- runtime·throw("traceback has leftover defers or panics");
- }
-
- return n;
-}
-
-void
-runtime·printcreatedby(G *gp)
-{
- int32 line;
- uintptr pc, tracepc;
- Func *f;
- String file;
-
- // Show what created goroutine, except main goroutine (goid 1).
- if((pc = gp->gopc) != 0 && (f = runtime·findfunc(pc)) != nil &&
- runtime·showframe(f, gp) && gp->goid != 1) {
- runtime·printf("created by %s\n", runtime·funcname(f));
- tracepc = pc; // back up to CALL instruction for funcline.
- if(pc > f->entry)
- tracepc -= PCQuantum;
- line = runtime·funcline(f, tracepc, &file);
- runtime·printf("\t%S:%d", file, line);
- if(pc > f->entry)
- runtime·printf(" +%p", (uintptr)(pc - f->entry));
- runtime·printf("\n");
- }
-}
-
-void
-runtime·traceback(uintptr pc, uintptr sp, uintptr lr, G *gp)
-{
- int32 n;
-
- if((runtime·readgstatus(gp)&~Gscan) == Gsyscall){
- // Override signal registers if blocked in system call.
- pc = gp->syscallpc;
- sp = gp->syscallsp;
- lr = 0;
- }
-
- // Print traceback. By default, omits runtime frames.
- // If that means we print nothing at all, repeat forcing all frames printed.
- n = runtime·gentraceback(pc, sp, lr, gp, 0, nil, TracebackMaxFrames, nil, nil, false);
- if(n == 0)
- runtime·gentraceback(pc, sp, lr, gp, 0, nil, TracebackMaxFrames, nil, nil, true);
- if(n == TracebackMaxFrames)
- runtime·printf("...additional frames elided...\n");
- runtime·printcreatedby(gp);
-}
-
-// func caller(n int) (pc uintptr, file string, line int, ok bool)
-int32
-runtime·callers(int32 skip, uintptr *pcbuf, int32 m)
-{
- uintptr pc, sp;
-
- sp = runtime·getcallersp(&skip);
- pc = (uintptr)runtime·getcallerpc(&skip);
-
- return runtime·gentraceback(pc, sp, 0, g, skip, pcbuf, m, nil, nil, false);
-}
-
-int32
-runtime·gcallers(G *gp, int32 skip, uintptr *pcbuf, int32 m)
-{
- return runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, skip, pcbuf, m, nil, nil, false);
-}
--- /dev/null
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import "unsafe"
+
+// sigtrampPC is the PC at the beginning of the jmpdefer assembly function.
+// The traceback needs to recognize it on link register architectures.
+var sigtrampPC uintptr
+
+var sigtramp struct{} // assembly function
+
+func init() {
+ f := sigtramp
+ sigtrampPC = **(**uintptr)(unsafe.Pointer(&f))
+ systraceback = traceback_windows
+}
+
+func traceback_windows(f *_func, frame *stkframe, gp *g, printing bool, callback func(*stkframe, unsafe.Pointer) bool, v unsafe.Pointer) (changed, aborted bool) {
+ // The main traceback thinks it has found a function. Check this.
+
+ // Windows exception handlers run on the actual g stack (there is room
+ // dedicated to this below the usual "bottom of stack"), not on a separate
+ // stack. As a result, we have to be able to unwind past the exception
+ // handler when called to unwind during stack growth inside the handler.
+ // Recognize the frame at the call to sighandler in sigtramp and unwind
+ // using the context argument passed to the call. This is awful.
+ if f != nil && f.entry == sigtrampPC && frame.pc > f.entry {
+ var r *context
+ // Invoke callback so that stack copier sees an uncopyable frame.
+ if callback != nil {
+ frame.continpc = frame.pc
+ frame.argp = 0
+ frame.arglen = 0
+ if !callback(frame, v) {
+ aborted = true
+ return
+ }
+ }
+ r = (*context)(unsafe.Pointer(frame.sp + ptrSize))
+ frame.pc = contextPC(r)
+ frame.sp = contextSP(r)
+ frame.lr = 0
+ frame.fp = 0
+ frame.fn = nil
+ if printing && showframe(nil, gp) {
+ print("----- exception handler -----\n")
+ }
+ f = findfunc(frame.pc)
+ if f == nil {
+ print("runtime: unknown pc ", hex(frame.pc), " after exception handler\n")
+ if callback != nil {
+ gothrow("unknown pc")
+ }
+ }
+ frame.fn = f
+ changed = true
+ return
+ }
+
+ return
+}
+++ /dev/null
-// Copyright 2009 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build amd64 amd64p32 386
-
-#include "runtime.h"
-#include "arch_GOARCH.h"
-#include "malloc.h"
-#include "funcdata.h"
-#ifdef GOOS_windows
-#include "defs_GOOS_GOARCH.h"
-#endif
-
-void runtime·sigpanic(void);
-void runtime·newproc(void);
-void runtime·deferproc(void);
-
-#ifdef GOOS_windows
-void runtime·sigtramp(void);
-#endif
-
-// This code is also used for the 386 tracebacks.
-// Use uintptr for an appropriate word-sized integer.
-
-// Generic traceback. Handles runtime stack prints (pcbuf == nil),
-// the runtime.Callers function (pcbuf != nil), as well as the garbage
-// collector (callback != nil). A little clunky to merge these, but avoids
-// duplicating the code and all its subtlety.
-int32
-runtime·gentraceback(uintptr pc0, uintptr sp0, uintptr lr0, G *gp, int32 skip, uintptr *pcbuf, int32 max, bool (*callback)(Stkframe*, void*), void *v, bool printall)
-{
- int32 i, n, nprint, line, gotraceback;
- uintptr tracepc, sparg;
- bool waspanic, wasnewproc, printing;
- Func *f, *flr;
- Stkframe frame;
- Stktop *stk;
- String file;
- Panic *panic;
- Defer *defer;
-
- USED(lr0);
-
- gotraceback = runtime·gotraceback(nil);
-
- if(pc0 == ~(uintptr)0 && sp0 == ~(uintptr)0) { // Signal to fetch saved values from gp.
- if(gp->syscallstack != (uintptr)nil) {
- pc0 = gp->syscallpc;
- sp0 = gp->syscallsp;
- } else {
- pc0 = gp->sched.pc;
- sp0 = gp->sched.sp;
- }
- }
-
- nprint = 0;
- runtime·memclr((byte*)&frame, sizeof frame);
- frame.pc = pc0;
- frame.sp = sp0;
- waspanic = false;
- wasnewproc = false;
- printing = pcbuf==nil && callback==nil;
- panic = gp->panic;
- defer = gp->defer;
-
- while(defer != nil && defer->argp == NoArgs)
- defer = defer->link;
- while(panic != nil && panic->defer == nil)
- panic = panic->link;
-
- // If the PC is zero, it's likely a nil function call.
- // Start in the caller's frame.
- if(frame.pc == 0) {
- frame.pc = *(uintptr*)frame.sp;
- frame.sp += sizeof(uintreg);
- }
-
- f = runtime·findfunc(frame.pc);
- if(f == nil) {
- if(callback != nil) {
- runtime·printf("runtime: unknown pc %p\n", frame.pc);
- runtime·throw("unknown pc");
- }
- return 0;
- }
- frame.fn = f;
-
- n = 0;
- stk = (Stktop*)gp->stackbase;
- while(n < max) {
- // Typically:
- // pc is the PC of the running function.
- // sp is the stack pointer at that program counter.
- // fp is the frame pointer (caller's stack pointer) at that program counter, or nil if unknown.
- // stk is the stack containing sp.
- // The caller's program counter is lr, unless lr is zero, in which case it is *(uintptr*)sp.
-
- if(frame.pc == (uintptr)runtime·lessstack) {
- // Hit top of stack segment. Unwind to next segment.
- frame.pc = stk->gobuf.pc;
- frame.sp = stk->gobuf.sp;
- frame.lr = 0;
- frame.fp = 0;
- frame.fn = nil;
- if(printing && runtime·showframe(nil, gp))
- runtime·printf("----- stack segment boundary -----\n");
- stk = (Stktop*)stk->stackbase;
-
- f = runtime·findfunc(frame.pc);
- if(f == nil) {
- runtime·printf("runtime: unknown pc %p after stack split\n", frame.pc);
- if(callback != nil)
- runtime·throw("unknown pc");
- }
- frame.fn = f;
- continue;
- }
-
- f = frame.fn;
-
-#ifdef GOOS_windows
- // Windows exception handlers run on the actual g stack (there is room
- // dedicated to this below the usual "bottom of stack"), not on a separate
- // stack. As a result, we have to be able to unwind past the exception
- // handler when called to unwind during stack growth inside the handler.
- // Recognize the frame at the call to sighandler in sigtramp and unwind
- // using the context argument passed to the call. This is awful.
- if(f != nil && f->entry == (uintptr)runtime·sigtramp && frame.pc > f->entry) {
- Context *r;
-
- // Invoke callback so that stack copier sees an uncopyable frame.
- if(callback != nil) {
- frame.continpc = frame.pc;
- frame.argp = 0;
- frame.arglen = 0;
- if(!callback(&frame, v))
- return n;
- }
- r = (Context*)((uintptr*)frame.sp)[1];
-#ifdef GOARCH_amd64
- frame.pc = r->Rip;
- frame.sp = r->Rsp;
-#else
- frame.pc = r->Eip;
- frame.sp = r->Esp;
-#endif
- frame.lr = 0;
- frame.fp = 0;
- frame.fn = nil;
- if(printing && runtime·showframe(nil, gp))
- runtime·printf("----- exception handler -----\n");
- f = runtime·findfunc(frame.pc);
- if(f == nil) {
- runtime·printf("runtime: unknown pc %p after exception handler\n", frame.pc);
- if(callback != nil)
- runtime·throw("unknown pc");
- }
- frame.fn = f;
- continue;
- }
-#endif
-
- // Found an actual function.
- // Derive frame pointer and link register.
- if(frame.fp == 0) {
- frame.fp = frame.sp + runtime·funcspdelta(f, frame.pc);
- frame.fp += sizeof(uintreg); // caller PC
- }
- if(runtime·topofstack(f)) {
- frame.lr = 0;
- flr = nil;
- } else {
- if(frame.lr == 0)
- frame.lr = ((uintreg*)frame.fp)[-1];
- flr = runtime·findfunc(frame.lr);
- if(flr == nil) {
- runtime·printf("runtime: unexpected return pc for %s called from %p\n", runtime·funcname(f), frame.lr);
- if(callback != nil)
- runtime·throw("unknown caller pc");
- }
- }
-
- frame.varp = frame.fp - sizeof(uintreg);
-
- // Derive size of arguments.
- // Most functions have a fixed-size argument block,
- // so we can use metadata about the function f.
- // Not all, though: there are some variadic functions
- // in package runtime and reflect, and for those we use call-specific
- // metadata recorded by f's caller.
- if(callback != nil || printing) {
- frame.argp = frame.fp;
- if(f->args != ArgsSizeUnknown)
- frame.arglen = f->args;
- else if(flr == nil)
- frame.arglen = 0;
- else if(frame.lr == (uintptr)runtime·lessstack)
- frame.arglen = stk->argsize;
- else if((i = runtime·funcarglen(flr, frame.lr)) >= 0)
- frame.arglen = i;
- else {
- runtime·printf("runtime: unknown argument frame size for %s called from %p [%s]\n",
- runtime·funcname(f), frame.lr, flr ? runtime·funcname(flr) : "?");
- if(callback != nil)
- runtime·throw("invalid stack");
- frame.arglen = 0;
- }
- }
-
- // Determine function SP where deferproc would find its arguments.
- // On x86 that's just the standard bottom-of-stack, so SP exactly.
- // If the previous frame was a direct call to newproc/deferproc, however,
- // the SP is two words lower than normal.
- sparg = frame.sp;
- if(wasnewproc)
- sparg += 2*sizeof(uintptr);
-
- // Determine frame's 'continuation PC', where it can continue.
- // Normally this is the return address on the stack, but if sigpanic
- // is immediately below this function on the stack, then the frame
- // stopped executing due to a trap, and frame.pc is probably not
- // a safe point for looking up liveness information. In this panicking case,
- // the function either doesn't return at all (if it has no defers or if the
- // defers do not recover) or it returns from one of the calls to
- // deferproc a second time (if the corresponding deferred func recovers).
- // It suffices to assume that the most recent deferproc is the one that
- // returns; everything live at earlier deferprocs is still live at that one.
- frame.continpc = frame.pc;
- if(waspanic) {
- if(panic != nil && panic->defer->argp == sparg)
- frame.continpc = panic->defer->pc;
- else if(defer != nil && defer->argp == sparg)
- frame.continpc = defer->pc;
- else
- frame.continpc = 0;
- }
-
- // Unwind our local panic & defer stacks past this frame.
- while(panic != nil && (panic->defer == nil || panic->defer->argp == sparg || panic->defer->argp == NoArgs))
- panic = panic->link;
- while(defer != nil && (defer->argp == sparg || defer->argp == NoArgs))
- defer = defer->link;
-
- if(skip > 0) {
- skip--;
- goto skipped;
- }
-
- if(pcbuf != nil)
- pcbuf[n] = frame.pc;
- if(callback != nil) {
- if(!callback(&frame, v))
- return n;
- }
- if(printing) {
- if(printall || runtime·showframe(f, gp)) {
- // Print during crash.
- // main(0x1, 0x2, 0x3)
- // /home/rsc/go/src/runtime/x.go:23 +0xf
- //
- tracepc = frame.pc; // back up to CALL instruction for funcline.
- if(n > 0 && frame.pc > f->entry && !waspanic)
- tracepc--;
- runtime·printf("%s(", runtime·funcname(f));
- for(i = 0; i < frame.arglen/sizeof(uintptr); i++) {
- if(i >= 10) {
- runtime·prints(", ...");
- break;
- }
- if(i != 0)
- runtime·prints(", ");
- runtime·printhex(((uintptr*)frame.argp)[i]);
- }
- runtime·prints(")\n");
- line = runtime·funcline(f, tracepc, &file);
- runtime·printf("\t%S:%d", file, line);
- if(frame.pc > f->entry)
- runtime·printf(" +%p", (uintptr)(frame.pc - f->entry));
- if(g->m->throwing > 0 && gp == g->m->curg || gotraceback >= 2)
- runtime·printf(" fp=%p sp=%p", frame.fp, frame.sp);
- runtime·printf("\n");
- nprint++;
- }
- }
- n++;
-
- skipped:
- waspanic = f->entry == (uintptr)runtime·sigpanic;
- wasnewproc = f->entry == (uintptr)runtime·newproc || f->entry == (uintptr)runtime·deferproc;
-
- // Do not unwind past the bottom of the stack.
- if(flr == nil)
- break;
-
- // Unwind to next frame.
- frame.fn = flr;
- frame.pc = frame.lr;
- frame.lr = 0;
- frame.sp = frame.fp;
- frame.fp = 0;
- }
-
- if(pcbuf == nil && callback == nil)
- n = nprint;
-
- // If callback != nil, we're being called to gather stack information during
- // garbage collection or stack growth. In that context, require that we used
- // up the entire defer stack. If not, then there is a bug somewhere and the
- // garbage collection or stack growth may not have seen the correct picture
- // of the stack. Crash now instead of silently executing the garbage collection
- // or stack copy incorrectly and setting up for a mysterious crash later.
- //
- // Note that panic != nil is okay here: there can be leftover panics,
- // because the defers on the panic stack do not nest in frame order as
- // they do on the defer stack. If you have:
- //
- // frame 1 defers d1
- // frame 2 defers d2
- // frame 3 defers d3
- // frame 4 panics
- // frame 4's panic starts running defers
- // frame 5, running d3, defers d4
- // frame 5 panics
- // frame 5's panic starts running defers
- // frame 6, running d4, garbage collects
- // frame 6, running d2, garbage collects
- //
- // During the execution of d4, the panic stack is d4 -> d3, which
- // is nested properly, and we'll treat frame 3 as resumable, because we
- // can find d3. (And in fact frame 3 is resumable. If d4 recovers
- // and frame 5 continues running, d3, d3 can recover and we'll
- // resume execution in (returning from) frame 3.)
- //
- // During the execution of d2, however, the panic stack is d2 -> d3,
- // which is inverted. The scan will match d2 to frame 2 but having
- // d2 on the stack until then means it will not match d3 to frame 3.
- // This is okay: if we're running d2, then all the defers after d2 have
- // completed and their corresponding frames are dead. Not finding d3
- // for frame 3 means we'll set frame 3's continpc == 0, which is correct
- // (frame 3 is dead). At the end of the walk the panic stack can thus
- // contain defers (d3 in this case) for dead frames. The inversion here
- // always indicates a dead frame, and the effect of the inversion on the
- // scan is to hide those dead frames, so the scan is still okay:
- // what's left on the panic stack are exactly (and only) the dead frames.
- //
- // We require callback != nil here because only when callback != nil
- // do we know that gentraceback is being called in a "must be correct"
- // context as opposed to a "best effort" context. The tracebacks with
- // callbacks only happen when everything is stopped nicely.
- // At other times, such as when gathering a stack for a profiling signal
- // or when printing a traceback during a crash, everything may not be
- // stopped nicely, and the stack walk may not be able to complete.
- // It's okay in those situations not to use up the entire defer stack:
- // incomplete information then is still better than nothing.
- if(callback != nil && n < max && defer != nil) {
- if(defer != nil)
- runtime·printf("runtime: g%D: leftover defer argp=%p pc=%p\n", gp->goid, defer->argp, defer->pc);
- if(panic != nil)
- runtime·printf("runtime: g%D: leftover panic argp=%p pc=%p\n", gp->goid, panic->defer->argp, panic->defer->pc);
- for(defer = gp->defer; defer != nil; defer = defer->link)
- runtime·printf("\tdefer %p argp=%p pc=%p\n", defer, defer->argp, defer->pc);
- for(panic = gp->panic; panic != nil; panic = panic->link) {
- runtime·printf("\tpanic %p defer %p", panic, panic->defer);
- if(panic->defer != nil)
- runtime·printf(" argp=%p pc=%p", panic->defer->argp, panic->defer->pc);
- runtime·printf("\n");
- }
- runtime·throw("traceback has leftover defers or panics");
- }
-
- return n;
-}
-
-void
-runtime·printcreatedby(G *gp)
-{
- int32 line;
- uintptr pc, tracepc;
- Func *f;
- String file;
-
- // Show what created goroutine, except main goroutine (goid 1).
- if((pc = gp->gopc) != 0 && (f = runtime·findfunc(pc)) != nil &&
- runtime·showframe(f, gp) && gp->goid != 1) {
- runtime·printf("created by %s\n", runtime·funcname(f));
- tracepc = pc; // back up to CALL instruction for funcline.
- if(pc > f->entry)
- tracepc -= PCQuantum;
- line = runtime·funcline(f, tracepc, &file);
- runtime·printf("\t%S:%d", file, line);
- if(pc > f->entry)
- runtime·printf(" +%p", (uintptr)(pc - f->entry));
- runtime·printf("\n");
- }
-}
-
-void
-runtime·traceback(uintptr pc, uintptr sp, uintptr lr, G *gp)
-{
- int32 n;
-
- USED(lr);
-
- if((runtime·readgstatus(gp)&~Gscan) == Gsyscall){
- // Override signal registers if blocked in system call.
- pc = gp->syscallpc;
- sp = gp->syscallsp;
- }
-
- // Print traceback. By default, omits runtime frames.
- // If that means we print nothing at all, repeat forcing all frames printed.
- n = runtime·gentraceback(pc, sp, 0, gp, 0, nil, TracebackMaxFrames, nil, nil, false);
- if(n == 0)
- n = runtime·gentraceback(pc, sp, 0, gp, 0, nil, TracebackMaxFrames, nil, nil, true);
- if(n == TracebackMaxFrames)
- runtime·printf("...additional frames elided...\n");
- runtime·printcreatedby(gp);
-}
-
-int32
-runtime·callers(int32 skip, uintptr *pcbuf, int32 m)
-{
- uintptr pc, sp;
-
- sp = runtime·getcallersp(&skip);
- pc = (uintptr)runtime·getcallerpc(&skip);
-
- return runtime·gentraceback(pc, sp, 0, g, skip, pcbuf, m, nil, nil, false);
-}
-
-int32
-runtime·gcallers(G *gp, int32 skip, uintptr *pcbuf, int32 m)
-{
- return runtime·gentraceback(~(uintptr)0, ~(uintptr)0, 0, gp, skip, pcbuf, m, nil, nil, false);
-}