diff options
| -rwxr-xr-x | misc/cgo/testsanitizers/test.bash | 10 | ||||
| -rw-r--r-- | misc/cgo/testsanitizers/tsan4.go | 34 | ||||
| -rw-r--r-- | src/cmd/cgo/out.go | 69 | ||||
| -rw-r--r-- | src/runtime/cgo.go | 4 | ||||
| -rw-r--r-- | src/runtime/cgo/callbacks.go | 12 | ||||
| -rw-r--r-- | src/runtime/cgo/gcc_util.c | 25 | ||||
| -rw-r--r-- | src/runtime/cgocall.go | 19 | ||||
| -rw-r--r-- | src/runtime/proc.go | 6 |
8 files changed, 105 insertions, 74 deletions
diff --git a/misc/cgo/testsanitizers/test.bash b/misc/cgo/testsanitizers/test.bash index 8718815d3e..c30df3b6c2 100755 --- a/misc/cgo/testsanitizers/test.bash +++ b/misc/cgo/testsanitizers/test.bash @@ -144,6 +144,16 @@ if test "$tsan" = "yes"; then status=1 fi + if ! go run tsan4.go 2>$err; then + cat $err + echo "FAIL: tsan4" + status=1 + elif grep -i warning $err >/dev/null 2>&1; then + cat $err + echo "FAIL: tsan4" + status=1 + fi + rm -f $err fi diff --git a/misc/cgo/testsanitizers/tsan4.go b/misc/cgo/testsanitizers/tsan4.go new file mode 100644 index 0000000000..f0c76d8411 --- /dev/null +++ b/misc/cgo/testsanitizers/tsan4.go @@ -0,0 +1,34 @@ +// Copyright 2016 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 main + +// Check that calls to C.malloc/C.free do not trigger TSAN false +// positive reports. + +// #cgo CFLAGS: -fsanitize=thread +// #cgo LDFLAGS: -fsanitize=thread +// #include <stdlib.h> +import "C" + +import ( + "runtime" + "sync" +) + +func main() { + var wg sync.WaitGroup + for i := 0; i < 10; i++ { + wg.Add(1) + go func() { + defer wg.Done() + for i := 0; i < 100; i++ { + p := C.malloc(C.size_t(i * 10)) + runtime.Gosched() + C.free(p) + } + }() + } + wg.Wait() +} diff --git a/src/cmd/cgo/out.go b/src/cmd/cgo/out.go index 256b059e57..5d6930d3ea 100644 --- a/src/cmd/cgo/out.go +++ b/src/cmd/cgo/out.go @@ -175,10 +175,11 @@ func (p *Package) writeDefs() { } fmt.Fprintf(fgo2, "\n") + callsMalloc := false for _, key := range nameKeys(p.Name) { n := p.Name[key] if n.FuncType != nil { - p.writeDefsFunc(fgo2, n) + p.writeDefsFunc(fgo2, n, &callsMalloc) } } @@ -189,6 +190,12 @@ func (p *Package) writeDefs() { } else { p.writeExports(fgo2, fm, fgcc, fgcch) } + + if callsMalloc && !*gccgo { + fmt.Fprint(fgo2, strings.Replace(cMallocDefGo, "PREFIX", cPrefix, -1)) + fmt.Fprint(fgcc, strings.Replace(strings.Replace(cMallocDefC, "PREFIX", cPrefix, -1), "PACKED", p.packedAttribute(), -1)) + } + if err := fgcc.Close(); err != nil { fatalf("%s", err) } @@ -352,7 +359,7 @@ func (p *Package) structType(n *Name) (string, int64) { return buf.String(), off } -func (p *Package) writeDefsFunc(fgo2 io.Writer, n *Name) { +func (p *Package) writeDefsFunc(fgo2 io.Writer, n *Name, callsMalloc *bool) { name := n.Go gtype := n.FuncType.Go void := gtype.Results == nil || len(gtype.Results.List) == 0 @@ -441,6 +448,9 @@ func (p *Package) writeDefsFunc(fgo2 io.Writer, n *Name) { if inProlog { fmt.Fprint(fgo2, builtinDefs[name]) + if strings.Contains(builtinDefs[name], "_cgo_cmalloc") { + *callsMalloc = true + } return } @@ -712,11 +722,13 @@ func (p *Package) writeExports(fgo2, fm, fgcc, fgcch io.Writer) { p.writeExportHeader(fgcch) fmt.Fprintf(fgcc, "/* Created by cgo - DO NOT EDIT. */\n") + fmt.Fprintf(fgcc, "#include <stdlib.h>\n") fmt.Fprintf(fgcc, "#include \"_cgo_export.h\"\n\n") fmt.Fprintf(fgcc, "extern void crosscall2(void (*fn)(void *, int, __SIZE_TYPE__), void *, int, __SIZE_TYPE__);\n") fmt.Fprintf(fgcc, "extern __SIZE_TYPE__ _cgo_wait_runtime_init_done();\n") fmt.Fprintf(fgcc, "extern void _cgo_release_context(__SIZE_TYPE__);\n\n") + fmt.Fprintf(fgcc, "extern char* _cgo_topofstack(void);") fmt.Fprintf(fgcc, "%s\n", tsanProlog) for _, exp := range p.ExpFunc { @@ -1352,9 +1364,6 @@ const goProlog = ` //go:linkname _cgo_runtime_cgocall runtime.cgocall func _cgo_runtime_cgocall(unsafe.Pointer, uintptr) int32 -//go:linkname _cgo_runtime_cmalloc runtime.cmalloc -func _cgo_runtime_cmalloc(uintptr) unsafe.Pointer - //go:linkname _cgo_runtime_cgocallback runtime.cgocallback func _cgo_runtime_cgocallback(unsafe.Pointer, unsafe.Pointer, uintptr, uintptr) @@ -1400,7 +1409,7 @@ func _Cfunc_GoBytes(p unsafe.Pointer, l _Ctype_int) []byte { const cStringDef = ` func _Cfunc_CString(s string) *_Ctype_char { - p := _cgo_runtime_cmalloc(uintptr(len(s)+1)) + p := _cgo_cmalloc(uint64(len(s)+1)) pp := (*[1<<30]byte)(p) copy(pp[:], s) pp[len(s)] = 0 @@ -1410,7 +1419,7 @@ func _Cfunc_CString(s string) *_Ctype_char { const cBytesDef = ` func _Cfunc_CBytes(b []byte) unsafe.Pointer { - p := _cgo_runtime_cmalloc(uintptr(len(b))) + p := _cgo_cmalloc(uint64(len(b))) pp := (*[1<<30]byte)(p) copy(pp[:], b) return p @@ -1419,7 +1428,7 @@ func _Cfunc_CBytes(b []byte) unsafe.Pointer { const cMallocDef = ` func _Cfunc__CMalloc(n _Ctype_size_t) unsafe.Pointer { - return _cgo_runtime_cmalloc(uintptr(n)) + return _cgo_cmalloc(uint64(n)) } ` @@ -1432,6 +1441,50 @@ var builtinDefs = map[string]string{ "_CMalloc": cMallocDef, } +// Definitions for C.malloc in Go and in C. We define it ourselves +// since we call it from functions we define, such as C.CString. +// Also, we have historically ensured that C.malloc does not return +// nil even for an allocation of 0. + +const cMallocDefGo = ` +//go:cgo_import_static _cgoPREFIX_Cfunc__Cmalloc +//go:linkname __cgofn__cgoPREFIX_Cfunc__Cmalloc _cgoPREFIX_Cfunc__Cmalloc +var __cgofn__cgoPREFIX_Cfunc__Cmalloc byte +var _cgoPREFIX_Cfunc__Cmalloc = unsafe.Pointer(&__cgofn__cgoPREFIX_Cfunc__Cmalloc) + +//go:cgo_unsafe_args +func _cgo_cmalloc(p0 uint64) (r1 unsafe.Pointer) { + _cgo_runtime_cgocall(_cgoPREFIX_Cfunc__Cmalloc, uintptr(unsafe.Pointer(&p0))) + return +} +` + +// cMallocDefC defines the C version of C.malloc for the gc compiler. +// It is defined here because C.CString and friends need a definition. +// We define it by hand, rather than simply inventing a reference to +// C.malloc, because <stdlib.h> may not have been included. +// This is approximately what writeOutputFunc would generate, but +// skips the cgo_topofstack code (which is only needed if the C code +// calls back into Go). This also avoids returning nil for an +// allocation of 0 bytes. +const cMallocDefC = ` +CGO_NO_SANITIZE_THREAD +void _cgoPREFIX_Cfunc__Cmalloc(void *v) { + struct { + unsigned long long p0; + void *r1; + } PACKED *a = v; + void *ret; + _cgo_tsan_acquire(); + ret = malloc(a->p0); + if (ret == 0 && a->p0 == 0) { + ret = malloc(1); + } + a->r1 = ret; + _cgo_tsan_release(); +} +` + func (p *Package) cPrologGccgo() string { return strings.Replace(strings.Replace(cPrologGccgo, "PREFIX", cPrefix, -1), "GCCGOSYMBOLPREF", p.gccgoSymbolPrefix(), -1) diff --git a/src/runtime/cgo.go b/src/runtime/cgo.go index 4fb4a613e0..9cf7b58a2f 100644 --- a/src/runtime/cgo.go +++ b/src/runtime/cgo.go @@ -11,8 +11,6 @@ import "unsafe" // Filled in by runtime/cgo when linked into binary. //go:linkname _cgo_init _cgo_init -//go:linkname _cgo_malloc _cgo_malloc -//go:linkname _cgo_free _cgo_free //go:linkname _cgo_thread_start _cgo_thread_start //go:linkname _cgo_sys_thread_create _cgo_sys_thread_create //go:linkname _cgo_notify_runtime_init_done _cgo_notify_runtime_init_done @@ -21,8 +19,6 @@ import "unsafe" var ( _cgo_init unsafe.Pointer - _cgo_malloc unsafe.Pointer - _cgo_free unsafe.Pointer _cgo_thread_start unsafe.Pointer _cgo_sys_thread_create unsafe.Pointer _cgo_notify_runtime_init_done unsafe.Pointer diff --git a/src/runtime/cgo/callbacks.go b/src/runtime/cgo/callbacks.go index d0f63fb4ff..9bde5a933f 100644 --- a/src/runtime/cgo/callbacks.go +++ b/src/runtime/cgo/callbacks.go @@ -52,18 +52,6 @@ func _cgo_panic(a unsafe.Pointer, n int32) { var x_cgo_init byte var _cgo_init = &x_cgo_init -//go:cgo_import_static x_cgo_malloc -//go:linkname x_cgo_malloc x_cgo_malloc -//go:linkname _cgo_malloc _cgo_malloc -var x_cgo_malloc byte -var _cgo_malloc = &x_cgo_malloc - -//go:cgo_import_static x_cgo_free -//go:linkname x_cgo_free x_cgo_free -//go:linkname _cgo_free _cgo_free -var x_cgo_free byte -var _cgo_free = &x_cgo_free - //go:cgo_import_static x_cgo_thread_start //go:linkname x_cgo_thread_start x_cgo_thread_start //go:linkname _cgo_thread_start _cgo_thread_start diff --git a/src/runtime/cgo/gcc_util.c b/src/runtime/cgo/gcc_util.c index e20d206be6..4111fe1195 100644 --- a/src/runtime/cgo/gcc_util.c +++ b/src/runtime/cgo/gcc_util.c @@ -4,31 +4,6 @@ #include "libcgo.h" -/* Stub for calling malloc from Go */ -void -x_cgo_malloc(void *p) -{ - struct a { - long long n; - void *ret; - } *a = p; - - a->ret = malloc(a->n); - if(a->ret == NULL && a->n == 0) - a->ret = malloc(1); -} - -/* Stub for calling free from Go */ -void -x_cgo_free(void *p) -{ - struct a { - void *arg; - } *a = p; - - free(a->arg); -} - /* Stub for creating a new thread */ void x_cgo_thread_start(ThreadStart *arg) diff --git a/src/runtime/cgocall.go b/src/runtime/cgocall.go index 1e0d4c7f19..0f8386b10f 100644 --- a/src/runtime/cgocall.go +++ b/src/runtime/cgocall.go @@ -145,25 +145,6 @@ func endcgo(mp *m) { unlockOSThread() // invalidates mp } -// Helper functions for cgo code. - -func cmalloc(n uintptr) unsafe.Pointer { - var args struct { - n uint64 - ret unsafe.Pointer - } - args.n = uint64(n) - cgocall(_cgo_malloc, unsafe.Pointer(&args)) - if args.ret == nil { - throw("C malloc failed") - } - return args.ret -} - -func cfree(p unsafe.Pointer) { - cgocall(_cgo_free, p) -} - // Call from C back to Go. //go:nosplit func cgocallbackg(ctxt uintptr) { diff --git a/src/runtime/proc.go b/src/runtime/proc.go index 8f98cfa8a4..ee89547104 100644 --- a/src/runtime/proc.go +++ b/src/runtime/proc.go @@ -155,12 +155,6 @@ func main() { if _cgo_thread_start == nil { throw("_cgo_thread_start missing") } - if _cgo_malloc == nil { - throw("_cgo_malloc missing") - } - if _cgo_free == nil { - throw("_cgo_free missing") - } if GOOS != "windows" { if _cgo_setenv == nil { throw("_cgo_setenv missing") |