From 5ad49c070734c57f35cfe045572fb22158870c78 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 18 Jun 1998 16:51:12 +0000 Subject: Update. 1998-06-18 16:40 Ulrich Drepper * libc.map: Add _dl_profile_map, _dl_profile_output, _dl_start_profile, _dl_mcount, _dl_mcount_wrapper. * elf/Makefile (routines): Add dl-profstub. * elf/dl-profstub.c: New file. * elf/dl-support.c: Don't define _dl_profile_map. * elf/rtld.c: Likewise. * elf/dlfcn.h: Define DL_CALL_FCT macro. * elf/ldsodefs.h: Declare _dl_profile_output, _dl_mcount_wrapper. Define _CALL_DL_FCT. * iconv/gconv.c: Use _CALL_DL_FCT to call function from dynamically loaded object. * iconv/gconv_db.c: Likewise. * iconv/skeleton.c: Likewise. * nss/getXXbyYY_r.c: Likewise. * nss/getXXent_r.c: Likewise. * nss/nsswitch.c: Likewise. --- elf/Makefile | 2 +- elf/dl-open.c | 24 +++++++++++++++++++++--- elf/dl-profstub.c | 43 +++++++++++++++++++++++++++++++++++++++++++ elf/dl-support.c | 1 - elf/dlfcn.h | 30 +++++++++++++++++++++++++++++- elf/ldsodefs.h | 19 +++++++++++++++++++ elf/rtld.c | 1 - 7 files changed, 113 insertions(+), 7 deletions(-) create mode 100644 elf/dl-profstub.c (limited to 'elf') diff --git a/elf/Makefile b/elf/Makefile index b2ea241808..dedc3d5074 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -22,7 +22,7 @@ subdir := elf headers = elf.h bits/elfclass.h bits/dlfcn.h link.h dlfcn.h routines = $(dl-routines) dl-open dl-close dl-symbol dl-support \ - dl-addr enbl-secure + dl-addr enbl-secure dl-profstub # The core dynamic linking functions are in libc for the static and # profiled libraries. diff --git a/elf/dl-open.c b/elf/dl-open.c index 4c4c8abdc5..2b9590913f 100644 --- a/elf/dl-open.c +++ b/elf/dl-open.c @@ -101,9 +101,27 @@ _dl_open (const char *file, int mode) magic ward. */ asm ("" : "=r" (reloc) : "0" (reloc)); - (*reloc) (l, _dl_object_relocation_scope (l), - ((mode & RTLD_BINDING_MASK) == RTLD_LAZY - || _dl_profile != NULL), _dl_profile != NULL); +#ifdef PIC + if (_dl_profile != NULL) + { + /* If this here is the shared object which we want to profile + make sure the profile is started. We can find out whether + this is necessary or not by observing the `_dl_profile_map' + variable. If was NULL but is not NULL afterwars we must + start the profiling. */ + struct link_map *old_profile_map = _dl_profile_map; + + (*reloc) (l, _dl_object_relocation_scope (l), 1, 1); + + if (old_profile_map == NULL && _dl_profile_map != NULL) + /* We must prepare the profiling. */ + _dl_start_profile (_dl_profile_map, _dl_profile_output); + } + else +#endif + (*reloc) (l, _dl_object_relocation_scope (l), + (mode & RTLD_BINDING_MASK) == RTLD_LAZY, 0); + *_dl_global_scope_end = NULL; } diff --git a/elf/dl-profstub.c b/elf/dl-profstub.c new file mode 100644 index 0000000000..9740c6adc4 --- /dev/null +++ b/elf/dl-profstub.c @@ -0,0 +1,43 @@ +/* Helper definitions for profiling of shared libraries. + Copyright (C) 1998 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper , 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include +#include +#include + +/* This is the map for the shared object we profile. It is defined here + only because we test for this value being NULL or not. */ +struct link_map *_dl_profile_map; + + +void +_dl_mcount_wrapper (ElfW(Addr) selfpc) +{ + _dl_mcount ((ElfW(Addr)) __builtin_return_address (0), selfpc); +} + + +void +_dl_mcount_wrapper_check (void *selfpc) +{ + if (_dl_profile_map != NULL) + _dl_mcount ((ElfW(Addr)) __builtin_return_address (0), + (ElfW(Addr)) selfpc); +} diff --git a/elf/dl-support.c b/elf/dl-support.c index 85f656c2fd..73c90c2f42 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -53,7 +53,6 @@ struct r_search_path *_dl_search_paths; /* We never do profiling. */ const char *_dl_profile; -struct link_map *_dl_profile_map; /* Names of shared object for which the RPATHs should be ignored. */ const char *_dl_inhibit_rpath; diff --git a/elf/dlfcn.h b/elf/dlfcn.h index 825b4843c1..e0b17d392a 100644 --- a/elf/dlfcn.h +++ b/elf/dlfcn.h @@ -1,5 +1,5 @@ /* User functions for run-time dynamic loading. - Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc. + Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -70,6 +70,34 @@ typedef struct } Dl_info; extern int dladdr __P ((const void *__address, Dl_info *__info)); +#ifdef __USE_GNU +/* To support profiling of shared objects it is a good idea to call + the function found using `dlsym' using the following macro since + these calls do not use the PLT. But this would mean the dynamic + loader has no chance to find out when the function is called. The + macro applies the necessary magic so that profiling is possible. + Rewrite + foo = (*fctp) (arg1, arg2); + into + foo = DL_CALL_FCT (fctp, (arg1, arg2)); +*/ +# if __GNUC__ >= 2 +/* Do not ever use this variable directly, it is internal! */ +extern struct link_map *_dl_profile_map; + +# define DL_CALL_FCT(fctp, args) \ + (__extension__ ({ if (_dl_profile_map != NULL) \ + _dl_mcount_wrapper_check (fctp); \ + (*fctp) args; }) +# else +/* This feature is not available without GCC. */ +# define DL_CALL_FCT(fctp, args) (*fctp) args +# endif + +/* This function calls the profiling functions. */ +extern void _dl_mcount_wrapper_check __P ((void *__selfpc)); +#endif + __END_DECLS #endif /* dlfcn.h */ diff --git a/elf/ldsodefs.h b/elf/ldsodefs.h index 45c2a5ec64..6814f25556 100644 --- a/elf/ldsodefs.h +++ b/elf/ldsodefs.h @@ -127,6 +127,8 @@ extern int _dl_zerofd; extern const char *_dl_profile; /* Map of shared object to be profiled. */ extern struct link_map *_dl_profile_map; +/* Filename of the output file. */ +extern const char *_dl_profile_output; /* If nonzero the appropriate debug information is printed. */ extern int _dl_debug_libs; @@ -409,6 +411,11 @@ extern void _dl_start_profile (struct link_map *map, const char *output_dir) /* The actual functions used to keep book on the calls. */ extern void _dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc); +/* This function is simply a wrapper around the _dl_mcount function + which does not require a FROMPC parameter since this is the + calling function. */ +extern void _dl_mcount_wrapper (ElfW(Addr) selfpc); + /* Show the members of the auxiliary array passed up from the kernel. */ extern void _dl_show_auxv (void) internal_function; @@ -424,6 +431,18 @@ extern const struct r_strlenpair *_dl_important_hwcaps (const char *platform, size_t *max_capstrlen) internal_function; + +/* When we do profiling we have the problem that uses of `dlopen'ed + objects don't use the PLT but instead use a pointer to the function. + We still want to have profiling data and in these cases we must do + the work of calling `_dl_mcount' ourself. The following macros + helps do it. */ +#define _CALL_DL_FCT(fctp, args) \ + ({ if (_dl_profile_map != NULL) \ + _dl_mcount_wrapper ((ElfW(Addr)) fctp); \ + (*fctp) args; \ + }) + __END_DECLS #endif /* ldsodefs.h */ diff --git a/elf/rtld.c b/elf/rtld.c index 028467f6f8..5bd4b7cd97 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -73,7 +73,6 @@ unsigned long _dl_hwcap; struct r_search_path *_dl_search_paths; const char *_dl_profile; const char *_dl_profile_output; -struct link_map *_dl_profile_map; int _dl_debug_libs; int _dl_debug_impcalls; int _dl_debug_bindings; -- cgit 1.4.1