From 0e56e5906568a70ee8c2f8596437e9194dc88b81 Mon Sep 17 00:00:00 2001 From: Ian Lance Taylor Date: Fri, 28 Sep 2012 14:48:30 +0000 Subject: libgo: Use libbacktrace rather than debug/elf registration. From-SVN: r191831 --- libgo/Makefile.am | 9 ++- libgo/Makefile.in | 12 +-- libgo/go/debug/elf/elf_test.go | 3 +- libgo/go/debug/elf/file_test.go | 3 +- libgo/go/debug/elf/runtime.go | 161 --------------------------------------- libgo/go/net/http/pprof/pprof.go | 1 - libgo/go/net/ip_test.go | 1 - libgo/go/runtime/debug/stack.go | 1 - libgo/go/runtime/pprof/pprof.go | 1 - libgo/go/testing/testing.go | 1 - libgo/runtime/go-caller.c | 150 +++++++++++++++++++++++++++--------- libgo/runtime/go-callers.c | 74 ++++++++---------- libgo/runtime/runtime.h | 4 +- 13 files changed, 165 insertions(+), 256 deletions(-) delete mode 100644 libgo/go/debug/elf/runtime.go (limited to 'libgo') diff --git a/libgo/Makefile.am b/libgo/Makefile.am index 3d2c8b9..084399d 100644 --- a/libgo/Makefile.am +++ b/libgo/Makefile.am @@ -39,7 +39,8 @@ ACLOCAL_AMFLAGS = -I ./config -I ../config AM_CFLAGS = -fexceptions -fplan9-extensions $(SPLIT_STACK) $(WARN_CFLAGS) \ $(STRINGOPS_FLAG) $(OSCFLAGS) \ - -I $(srcdir)/../libgcc -I $(MULTIBUILDTOP)../../gcc/include + -I $(srcdir)/../libgcc -I $(srcdir)/../libbacktrace \ + -I $(MULTIBUILDTOP)../../gcc/include if USING_SPLIT_STACK AM_LDFLAGS = -XCClinker $(SPLIT_STACK) @@ -1062,8 +1063,7 @@ go_debug_dwarf_files = \ go/debug/dwarf/unit.go go_debug_elf_files = \ go/debug/elf/elf.go \ - go/debug/elf/file.go \ - go/debug/elf/runtime.go + go/debug/elf/file.go go_debug_gosym_files = \ go/debug/gosym/pclntab.go \ go/debug/gosym/symtab.go @@ -1782,7 +1782,8 @@ libgo_la_SOURCES = $(runtime_files) libgo_la_LDFLAGS = $(PTHREAD_CFLAGS) $(AM_LDFLAGS) libgo_la_LIBADD = \ - $(libgo_go_objs) $(LIBFFI) $(PTHREAD_LIBS) $(MATH_LIBS) $(NET_LIBS) + $(libgo_go_objs) ../libbacktrace/libbacktrace.la \ + $(LIBFFI) $(PTHREAD_LIBS) $(MATH_LIBS) $(NET_LIBS) libgobegin_a_SOURCES = \ runtime/go-main.c diff --git a/libgo/Makefile.in b/libgo/Makefile.in index d8b6890..8fd0986 100644 --- a/libgo/Makefile.in +++ b/libgo/Makefile.in @@ -169,7 +169,8 @@ am__DEPENDENCIES_2 = bufio.lo bytes.lo bytes/index.lo crypto.lo \ text/tabwriter.lo text/template.lo text/template/parse.lo \ testing/iotest.lo testing/quick.lo unicode/utf16.lo \ unicode/utf8.lo -libgo_la_DEPENDENCIES = $(am__DEPENDENCIES_2) $(am__DEPENDENCIES_1) \ +libgo_la_DEPENDENCIES = $(am__DEPENDENCIES_2) \ + ../libbacktrace/libbacktrace.la $(am__DEPENDENCIES_1) \ $(am__DEPENDENCIES_1) $(am__DEPENDENCIES_1) \ $(am__DEPENDENCIES_1) @LIBGO_IS_LINUX_FALSE@am__objects_1 = lock_sema.lo thread-sema.lo @@ -435,7 +436,8 @@ AM_CPPFLAGS = -I $(srcdir)/runtime $(LIBFFIINCS) $(PTHREAD_CFLAGS) ACLOCAL_AMFLAGS = -I ./config -I ../config AM_CFLAGS = -fexceptions -fplan9-extensions $(SPLIT_STACK) $(WARN_CFLAGS) \ $(STRINGOPS_FLAG) $(OSCFLAGS) \ - -I $(srcdir)/../libgcc -I $(MULTIBUILDTOP)../../gcc/include + -I $(srcdir)/../libgcc -I $(srcdir)/../libbacktrace \ + -I $(MULTIBUILDTOP)../../gcc/include @USING_SPLIT_STACK_TRUE@AM_LDFLAGS = -XCClinker $(SPLIT_STACK) @@ -1287,8 +1289,7 @@ go_debug_dwarf_files = \ go_debug_elf_files = \ go/debug/elf/elf.go \ - go/debug/elf/file.go \ - go/debug/elf/runtime.go + go/debug/elf/file.go go_debug_gosym_files = \ go/debug/gosym/pclntab.go \ @@ -1932,7 +1933,8 @@ libgo_go_objs = \ libgo_la_SOURCES = $(runtime_files) libgo_la_LDFLAGS = $(PTHREAD_CFLAGS) $(AM_LDFLAGS) libgo_la_LIBADD = \ - $(libgo_go_objs) $(LIBFFI) $(PTHREAD_LIBS) $(MATH_LIBS) $(NET_LIBS) + $(libgo_go_objs) ../libbacktrace/libbacktrace.la \ + $(LIBFFI) $(PTHREAD_LIBS) $(MATH_LIBS) $(NET_LIBS) libgobegin_a_SOURCES = \ runtime/go-main.c diff --git a/libgo/go/debug/elf/elf_test.go b/libgo/go/debug/elf/elf_test.go index b8cdbcc..67b961b 100644 --- a/libgo/go/debug/elf/elf_test.go +++ b/libgo/go/debug/elf/elf_test.go @@ -2,10 +2,9 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -package elf_test +package elf import ( - . "debug/elf" "fmt" "testing" ) diff --git a/libgo/go/debug/elf/file_test.go b/libgo/go/debug/elf/file_test.go index 105b697..98f2723c 100644 --- a/libgo/go/debug/elf/file_test.go +++ b/libgo/go/debug/elf/file_test.go @@ -2,11 +2,10 @@ // Use of this source code is governed by a BSD-style // license that can be found in the LICENSE file. -package elf_test +package elf import ( "debug/dwarf" - . "debug/elf" "encoding/binary" "net" "os" diff --git a/libgo/go/debug/elf/runtime.go b/libgo/go/debug/elf/runtime.go deleted file mode 100644 index 17cb6fb..0000000 --- a/libgo/go/debug/elf/runtime.go +++ /dev/null @@ -1,161 +0,0 @@ -// Copyright 2012 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. - -// This is gccgo-specific code that uses DWARF information to fetch -// file/line information for PC values. This package registers itself -// with the runtime package. - -package elf - -import ( - "debug/dwarf" - "debug/macho" - "os" - "runtime" - "sort" - "sync" -) - -func init() { - // Register our lookup functions with the runtime package. - runtime.RegisterDebugLookup(funcFileLine, symbolValue) -} - -// The file struct holds information for a specific file that is part -// of the execution. -type file struct { - elf *File // If ELF - macho *macho.File // If Mach-O - dwarf *dwarf.Data // DWARF information - - symsByName []sym // Sorted by name - symsByAddr []sym // Sorted by address -} - -// Sort symbols by name. -type symsByName []sym - -func (s symsByName) Len() int { return len(s) } -func (s symsByName) Less(i, j int) bool { return s[i].name < s[j].name } -func (s symsByName) Swap(i, j int) { s[i], s[j] = s[j], s[i] } - -// Sort symbols by address. -type symsByAddr []sym - -func (s symsByAddr) Len() int { return len(s) } -func (s symsByAddr) Less(i, j int) bool { return s[i].addr < s[j].addr } -func (s symsByAddr) Swap(i, j int) { s[i], s[j] = s[j], s[i] } - -// The sym structure holds the information we care about for a symbol, -// namely name and address. -type sym struct { - name string - addr uintptr -} - -// Open an input file. -func open(name string) (*file, error) { - efile, err := Open(name) - var mfile *macho.File - if err != nil { - var merr error - mfile, merr = macho.Open(name) - if merr != nil { - return nil, err - } - } - - r := &file{elf: efile, macho: mfile} - - if efile != nil { - r.dwarf, err = efile.DWARF() - } else { - r.dwarf, err = mfile.DWARF() - } - if err != nil { - return nil, err - } - - var syms []sym - if efile != nil { - esyms, err := efile.Symbols() - if err != nil { - return nil, err - } - syms = make([]sym, 0, len(esyms)) - for _, s := range esyms { - if ST_TYPE(s.Info) == STT_FUNC { - syms = append(syms, sym{s.Name, uintptr(s.Value)}) - } - } - } else { - syms = make([]sym, 0, len(mfile.Symtab.Syms)) - for _, s := range mfile.Symtab.Syms { - syms = append(syms, sym{s.Name, uintptr(s.Value)}) - } - } - - r.symsByName = make([]sym, len(syms)) - copy(r.symsByName, syms) - sort.Sort(symsByName(r.symsByName)) - - r.symsByAddr = syms - sort.Sort(symsByAddr(r.symsByAddr)) - - return r, nil -} - -// The main executable -var executable *file - -// Only open the executable once. -var executableOnce sync.Once - -func openExecutable() { - executableOnce.Do(func() { - f, err := open("/proc/self/exe") - if err != nil { - f, err = open(os.Args[0]) - if err != nil { - return - } - } - executable = f - }) -} - -// The funcFileLine function looks up the function name, file name, -// and line number for a PC value. -func funcFileLine(pc uintptr, function *string, file *string, line *int) bool { - openExecutable() - if executable == nil || executable.dwarf == nil { - return false - } - f, ln, err := executable.dwarf.FileLine(uint64(pc)) - if err != nil { - return false - } - *file = f - *line = ln - - *function = "" - if len(executable.symsByAddr) > 0 && pc >= executable.symsByAddr[0].addr { - i := sort.Search(len(executable.symsByAddr), - func(i int) bool { return executable.symsByAddr[i].addr > pc }) - *function = executable.symsByAddr[i-1].name - } - - return true -} - -// The symbolValue function fetches the value of a symbol. -func symbolValue(name string, val *uintptr) bool { - i := sort.Search(len(executable.symsByName), - func(i int) bool { return executable.symsByName[i].name >= name }) - if i >= len(executable.symsByName) || executable.symsByName[i].name != name { - return false - } - *val = executable.symsByName[i].addr - return true -} diff --git a/libgo/go/net/http/pprof/pprof.go b/libgo/go/net/http/pprof/pprof.go index b8874f3..06fcde1 100644 --- a/libgo/go/net/http/pprof/pprof.go +++ b/libgo/go/net/http/pprof/pprof.go @@ -35,7 +35,6 @@ package pprof import ( "bufio" "bytes" - _ "debug/elf" "fmt" "html/template" "io" diff --git a/libgo/go/net/ip_test.go b/libgo/go/net/ip_test.go index d0e987b..df647ef 100644 --- a/libgo/go/net/ip_test.go +++ b/libgo/go/net/ip_test.go @@ -6,7 +6,6 @@ package net import ( "bytes" - _ "debug/elf" "reflect" "runtime" "testing" diff --git a/libgo/go/runtime/debug/stack.go b/libgo/go/runtime/debug/stack.go index fc74e53..a533a5c 100644 --- a/libgo/go/runtime/debug/stack.go +++ b/libgo/go/runtime/debug/stack.go @@ -8,7 +8,6 @@ package debug import ( "bytes" - _ "debug/elf" "fmt" "io/ioutil" "os" diff --git a/libgo/go/runtime/pprof/pprof.go b/libgo/go/runtime/pprof/pprof.go index 87f17d2..f67e8a8 100644 --- a/libgo/go/runtime/pprof/pprof.go +++ b/libgo/go/runtime/pprof/pprof.go @@ -11,7 +11,6 @@ package pprof import ( "bufio" "bytes" - _ "debug/elf" "fmt" "io" "runtime" diff --git a/libgo/go/testing/testing.go b/libgo/go/testing/testing.go index 1cb8a07..f59ce8e 100644 --- a/libgo/go/testing/testing.go +++ b/libgo/go/testing/testing.go @@ -79,7 +79,6 @@ package testing import ( - _ "debug/elf" "flag" "fmt" "os" diff --git a/libgo/runtime/go-caller.c b/libgo/runtime/go-caller.c index b99d20c..7d5df85 100644 --- a/libgo/runtime/go-caller.c +++ b/libgo/runtime/go-caller.c @@ -8,41 +8,99 @@ #include +#include "backtrace.h" + #include "runtime.h" #include "go-string.h" /* Get the function name, file name, and line number for a PC value. - We use the DWARF debug information to get this. Rather than write - a whole new library in C, we use the existing Go library. - Unfortunately, the Go library is only available if the debug/elf - package is imported (we use debug/elf for both ELF and Mach-O, in - this case). We arrange for the debug/elf package to register - itself, and tweak the various packages that need this information - to import debug/elf where possible. */ + We use the backtrace library to get this. */ + +/* Data structure to gather file/line information. */ + +struct caller +{ + struct __go_string fn; + struct __go_string file; + int line; +}; + +/* Collect file/line information for a PC value. If this is called + more than once, due to inlined functions, we use the last call, as + that is usually the most useful one. */ + +static int +callback (void *data, uintptr_t pc __attribute__ ((unused)), + const char *filename, int lineno, const char *function) +{ + struct caller *c = (struct caller *) data; + + if (function == NULL) + { + c->fn.__data = NULL; + c->fn.__length = 0; + } + else + { + char *s; + + c->fn.__length = __builtin_strlen (function); + s = runtime_malloc (c->fn.__length); + __builtin_memcpy (s, function, c->fn.__length); + c->fn.__data = (unsigned char *) s; + } + + if (filename == NULL) + { + c->file.__data = NULL; + c->file.__length = 0; + } + else + { + char *s; + + c->file.__length = __builtin_strlen (filename); + s = runtime_malloc (c->file.__length); + __builtin_memcpy (s, filename, c->file.__length); + c->file.__data = (unsigned char *) s; + } + + c->line = lineno; + + return 0; +} -/* The function that returns function/file/line information. */ +/* The error callback for backtrace_pcinfo and backtrace_syminfo. */ -typedef _Bool (*infofn_type) (uintptr_t, struct __go_string *, - struct __go_string *, int *); -static infofn_type infofn; +static void +error_callback (void *data __attribute__ ((unused)), + const char *msg, int errnum) +{ + if (errnum == -1) + return; + if (errnum > 0) + runtime_printf ("%s errno %d\n", msg, errnum); + runtime_throw (msg); +} + +/* The backtrace library state. */ -/* The function that returns the value of a symbol, used to get the - entry address of a function. */ +static void *back_state; -typedef _Bool (*symvalfn_type) (struct __go_string, uintptr_t *); -static symvalfn_type symvalfn; +/* A lock to control creating back_state. */ -/* This is called by debug/elf to register the function that returns - function/file/line information. */ +static Lock back_state_lock; -void RegisterDebugLookup (infofn_type, symvalfn_type) - __asm__ ("runtime.RegisterDebugLookup"); +/* Fetch back_state, creating it if necessary. */ -void -RegisterDebugLookup (infofn_type pi, symvalfn_type ps) +struct backtrace_state * +__go_get_backtrace_state () { - infofn = pi; - symvalfn = ps; + runtime_lock (&back_state_lock); + if (back_state == NULL) + back_state = backtrace_create_state (NULL, 1, error_callback, NULL); + runtime_unlock (&back_state_lock); + return back_state; } /* Return function/file/line information for PC. */ @@ -51,19 +109,38 @@ _Bool __go_file_line (uintptr pc, struct __go_string *fn, struct __go_string *file, int *line) { - if (infofn == NULL) - return 0; - return infofn (pc, fn, file, line); + struct caller c; + + runtime_memclr (&c, sizeof c); + backtrace_pcinfo (__go_get_backtrace_state (), pc, callback, + error_callback, &c); + *fn = c.fn; + *file = c.file; + *line = c.line; + return c.file.__length > 0; } -/* Return the value of a symbol. */ +/* Collect symbol information. */ -_Bool -__go_symbol_value (struct __go_string sym, uintptr_t *val) +static void +syminfo_callback (void *data, uintptr_t pc __attribute__ ((unused)), + const char *symname __attribute__ ((unused)), + uintptr_t address) +{ + uintptr_t *pval = (uintptr_t *) data; + + *pval = address; +} + +/* Set *VAL to the value of the symbol for PC. */ + +static _Bool +__go_symbol_value (uintptr_t pc, uintptr_t *val) { - if (symvalfn == NULL) - return 0; - return symvalfn (sym, val); + *val = 0; + backtrace_syminfo (__go_get_backtrace_state (), pc, syminfo_callback, + error_callback, &val); + return *val != 0; } /* The values returned by runtime.Caller. */ @@ -112,12 +189,15 @@ FuncForPC (uintptr_t pc) if (!__go_file_line (pc, &fn, &file, &line)) return NULL; - if (!__go_symbol_value (fn, &val)) - return NULL; ret = (Func *) runtime_malloc (sizeof (*ret)); ret->name = fn; - ret->entry = val; + + if (__go_symbol_value (pc, &val)) + ret->entry = val; + else + ret->entry = 0; + return ret; } diff --git a/libgo/runtime/go-callers.c b/libgo/runtime/go-callers.c index 3eea5f2..71d69f6 100644 --- a/libgo/runtime/go-callers.c +++ b/libgo/runtime/go-callers.c @@ -6,64 +6,56 @@ #include "config.h" -#include "unwind.h" +#include "backtrace.h" #include "runtime.h" -/* Argument passed to backtrace function. */ +/* Argument passed to callback function. */ struct callers_data { - int skip; uintptr *pcbuf; int index; int max; }; -static _Unwind_Reason_Code -backtrace (struct _Unwind_Context *context, void *varg) +/* Callback function for backtrace_simple. Just collect the PC + values. Return zero to continue, non-zero to stop. */ + +static int +callback (void *data, uintptr_t pc) +{ + struct callers_data *arg = (struct callers_data *) data; + + arg->pcbuf[arg->index] = pc; + ++arg->index; + return arg->index >= arg->max; +} + +/* Error callback. */ + +static void +error_callback (void *data __attribute__ ((unused)), + const char *msg, int errnum) { - struct callers_data *arg = (struct callers_data *) varg; - uintptr pc; - int ip_before_insn = 0; - -#ifdef HAVE_GETIPINFO - pc = _Unwind_GetIPInfo (context, &ip_before_insn); -#else - pc = _Unwind_GetIP (context); -#endif - - /* FIXME: If PC is in the __morestack routine, we should ignore - it. */ - - if (arg->skip > 0) - --arg->skip; - else if (arg->index >= arg->max) - return _URC_END_OF_STACK; - else - { - /* Here PC will be the return address. We actually want the - address of the call instruction, so back up one byte and - count on the lookup routines handling that correctly. */ - if (!ip_before_insn) - --pc; - arg->pcbuf[arg->index] = pc; - ++arg->index; - } - return _URC_NO_REASON; + if (errnum != 0) + runtime_printf ("%s errno %d\n", msg, errnum); + runtime_throw (msg); } +/* Gather caller PC's. */ + int32 runtime_callers (int32 skip, uintptr *pcbuf, int32 m) { - struct callers_data arg; - - arg.skip = skip + 1; - arg.pcbuf = pcbuf; - arg.index = 0; - arg.max = m; - _Unwind_Backtrace (backtrace, &arg); - return arg.index; + struct callers_data data; + + data.pcbuf = pcbuf; + data.index = 0; + data.max = m; + backtrace_simple (__go_get_backtrace_state (), skip + 1, callback, + error_callback, &data); + return data.index; } int Callers (int, struct __go_open_array) diff --git a/libgo/runtime/runtime.h b/libgo/runtime/runtime.h index cebc1fd..f96d740 100644 --- a/libgo/runtime/runtime.h +++ b/libgo/runtime/runtime.h @@ -517,6 +517,8 @@ void __go_register_gc_roots(struct root_list*); // the stacks are allocated by the splitstack library. extern uintptr runtime_stacks_sys; -extern _Bool __go_file_line (uintptr, String*, String*, int *); +struct backtrace_state; +extern struct backtrace_state *__go_get_backtrace_state(void); +extern _Bool __go_file_line(uintptr, String*, String*, int *); int32 getproccount(void); -- cgit v1.1