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-rw-r--r--elf/Makefile3
-rw-r--r--elf/dl-load.c7
-rw-r--r--elf/dl-profile.c267
-rw-r--r--elf/dl-reloc.c3
-rw-r--r--elf/dl-runtime.c71
-rw-r--r--elf/dl-support.c4
-rw-r--r--elf/do-rel.h6
-rw-r--r--elf/dynamic-link.h13
-rw-r--r--elf/link.h13
-rw-r--r--elf/rtld.c32
10 files changed, 403 insertions, 16 deletions
diff --git a/elf/Makefile b/elf/Makefile
index e447114..904099c 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -27,7 +27,8 @@ routines = $(dl-routines) dl-open dl-close dl-symbol dl-support \
# The core dynamic linking functions are in libc for the static and
# profiled libraries.
dl-routines = $(addprefix dl-,load cache lookup object reloc deps \
- runtime error init fini debug misc)
+ runtime error init fini debug misc \
+ profile)
# But they are absent from the shared libc, because that code is in ld.so.
elide-routines.so = $(dl-routines) dl-support enbl-secure
diff --git a/elf/dl-load.c b/elf/dl-load.c
index 1301e73..f7c2c53 100644
--- a/elf/dl-load.c
+++ b/elf/dl-load.c
@@ -193,7 +193,10 @@ fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
"cannot create cache for search path");
dirp->dirnamelen = len;
- dirp->dirstatus = unknown;
+ /* We have to make sure all the relative directories are never
+ ignored. The current directory might change and all our
+ saved information would be void. */
+ dirp->dirstatus = cp[0] != '/' ? existing : unknown;
/* Add the name of the machine dependent directory if a machine
is defined. */
@@ -212,7 +215,7 @@ fillin_rpath (char *rpath, struct r_search_path_elem **result, const char *sep,
tmp[len + _dl_platformlen + 1] = '\0';
dirp->dirname = tmp;
- dirp->machdirstatus = unknown;
+ dirp->machdirstatus = dirp->dirstatus;
if (max_dirnamelen < dirp->machdirnamelen)
max_dirnamelen = dirp->machdirnamelen;
diff --git a/elf/dl-profile.c b/elf/dl-profile.c
new file mode 100644
index 0000000..cc25b61
--- /dev/null
+++ b/elf/dl-profile.c
@@ -0,0 +1,267 @@
+/* Profiling of shared libraries.
+ Copyright (C) 1997 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@cygnus.com>, 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 <errno.h>
+#include <fcntl.h>
+#include <inttypes.h>
+#include <link.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/gmon.h>
+#include <sys/gmon_out.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+
+/* The LD_PROFILE feature has to be implemented different to the
+ normal profiling using the gmon/ functions. The problem is that an
+ arbitrary amount of processes simulataneously can be run using
+ profiling and all write the results in the same file. To provide
+ this mechanism one could implement a complicated mechanism to merge
+ the content of two profiling runs or one could extend the file
+ format to allow more than one data set. For the second solution we
+ would have the problem that the file can grow in size beyond any
+ limit and both solutions have the problem that the concurrency of
+ writing the results is a big problem.
+
+ Another much simpler method is to use mmap to map the same file in
+ all using programs and modify the data in the mmap'ed area and so
+ also automatically on the disk. Using the MAP_SHARED option of
+ mmap(2) this can be done without big problems in more than one
+ file.
+
+ This approach is very different from the normal profiling. We have
+ to use the profiling data in exactly the way they are expected to
+ be written to disk. */
+
+extern char *_strerror_internal __P ((int, char *buf, size_t));
+
+extern int __profile_frequency __P ((void));
+
+
+static struct gmonparam param;
+
+/* We define a special type to address the elements of the arc table.
+ This is basically the `gmon_cg_arc_record' format but it includes
+ the room for the tag and it uses real types. */
+struct here_cg_arc_record
+ {
+ char tag;
+ uintptr_t from_pc __attribute__ ((packed));
+ uintptr_t self_pc __attribute__ ((packed));
+ uint32_t count __attribute__ ((packed));
+ };
+
+static struct here_cg_arc_record *data;
+
+
+void
+_dl_start_profile (struct link_map *map, const char *output_dir)
+{
+ char *filename;
+ int fd;
+ struct stat st;
+ const ElfW(Phdr) *ph;
+ ElfW(Addr) mapstart = ~((ElfW(Addr)) 0);
+ ElfW(Addr) mapend = 0;
+ off_t expected_size;
+ struct gmon_hdr gmon_hdr;
+ struct gmon_hist_hdr hist_hdr;
+ struct gmon_hdr *addr;
+ char *hist;
+
+ /* Compute the size of the sections which contain program code. */
+ for (ph = map->l_phdr; ph < &map->l_phdr[map->l_phnum]; ++ph)
+ if (ph->p_type == PT_LOAD && (ph->p_flags & PF_X))
+ {
+ ElfW(Addr) start = (ph->p_vaddr & ~(_dl_pagesize - 1));
+ ElfW(Addr) end = ((ph->p_vaddr + ph->p_memsz + _dl_pagesize - 1)
+ & ~(_dl_pagesize - 1));
+
+ if (start < mapstart)
+ mapstart = start;
+ if (end > mapend)
+ mapend = end;
+ }
+
+ /* Now we can compute the size of the profiling data. This is done
+ with the same formulars as in `monstartup' (see gmon.c). */
+ param.state = GMON_PROF_OFF;
+ param.lowpc = mapstart + map->l_addr;
+ param.highpc = mapend + map->l_addr;
+ param.textsize = mapend - mapstart;
+ param.kcountsize = param.textsize / HISTFRACTION;
+ param.hashfraction = HASHFRACTION;
+ param.log_hashfraction = -1;
+ if ((HASHFRACTION & (HASHFRACTION - 1)) == 0)
+ /* If HASHFRACTION is a power of two, mcount can use shifting
+ instead of integer division. Precompute shift amount. */
+ param.log_hashfraction = ffs (param.hashfraction
+ * sizeof (*param.froms)) - 1;
+ param.fromssize = param.textsize / HASHFRACTION;
+ param.tolimit = param.textsize * ARCDENSITY / 100;
+ if (param.tolimit < MINARCS)
+ param.tolimit = MINARCS;
+ if (param.tolimit > MAXARCS)
+ param.tolimit = MAXARCS;
+ param.tossize = param.tolimit * sizeof (struct tostruct);
+
+ expected_size = (sizeof (struct gmon_hdr)
+ + 1 + sizeof (struct gmon_hist_hdr)
+ + ((1 + sizeof (struct gmon_cg_arc_record))
+ * (param.fromssize / sizeof (*param.froms))));
+
+ /* Create the gmon_hdr we expect or write. */
+ memset (&gmon_hdr, '\0', sizeof (struct gmon_hdr));
+ memcpy (&gmon_hdr.cookie[0], GMON_MAGIC, sizeof (gmon_hdr.cookie));
+ *(int32_t *) gmon_hdr.version = GMON_VERSION;
+
+ /* Create the hist_hdr we expect or write. */
+ *(char **) hist_hdr.low_pc = (char *) mapstart;
+ *(char **) hist_hdr.high_pc = (char *) mapend;
+ *(int32_t *) hist_hdr.hist_size = param.kcountsize / sizeof (HISTCOUNTER);
+ *(int32_t *) hist_hdr.prof_rate = __profile_frequency ();
+ strncpy (hist_hdr.dimen, "seconds", sizeof (hist_hdr.dimen));
+ hist_hdr.dimen_abbrev = 's';
+
+ /* First determine the output name. We write in the directory
+ OUTPUT_DIR and the name is composed from the shared objects
+ soname (or the file name) and the ending ".profile". */
+ filename = (char *) alloca (strlen (output_dir) + 1 + strlen (_dl_profile)
+ + sizeof ".profile");
+ __stpcpy (__stpcpy (__stpcpy (__stpcpy (filename, output_dir), "/"),
+ _dl_profile),
+ ".profile");
+
+ fd = __open (filename, O_RDWR | O_CREAT, 0666);
+ if (fd == -1)
+ /* We cannot write the profiling data so don't do anthing. */
+ return;
+
+ if (fstat (fd, &st) < 0 || !S_ISREG (st.st_mode))
+ {
+ /* Not stat'able or not a regular file => don't use it. */
+ close (fd);
+ return;
+ }
+
+ /* Test the size. If it does not match what we expect from the size
+ values in the map MAP we don't use it and warn the user. */
+ if (st.st_size == 0)
+ {
+ /* We have to create the file. */
+ char buf[_dl_pagesize];
+
+ memset (buf, '\0', _dl_pagesize);
+
+ if (__lseek (fd, expected_size & ~(_dl_pagesize - 1), SEEK_SET) == -1)
+ {
+ char buf[400];
+ int errnum;
+ cannot_create:
+ errnum = errno;
+ __close (fd);
+ fprintf (stderr, "%s: cannot create file: %s\n", filename,
+ _strerror_internal (errnum, buf, sizeof buf));
+ return;
+ }
+
+ if (TEMP_FAILURE_RETRY (__write (fd, buf, (expected_size
+ & (_dl_pagesize - 1)))) < 0)
+ goto cannot_create;
+ }
+ else if (st.st_size != expected_size)
+ {
+ __close (fd);
+ wrong_format:
+ fprintf (stderr, "%s: file is no correct profile data file for `%s'\n",
+ filename, _dl_profile);
+ return;
+ }
+
+ addr = (void *) __mmap (NULL, expected_size, PROT_READ|PROT_WRITE,
+ MAP_SHARED|MAP_FILE, fd, 0);
+ if (addr == (void *) -1)
+ {
+ char buf[400];
+ int errnum = errno;
+ __close (fd);
+ fprintf (stderr, "%s: cannot map file: %s\n", filename,
+ _strerror_internal (errnum, buf, sizeof buf));
+ return;
+ }
+
+ /* We don't need the file desriptor anymore. */
+ __close (fd);
+
+ /* Pointer to data after the header. */
+ hist = (char *) (addr + 1);
+
+ /* Compute pointer to array of the arc information. */
+ data = (struct here_cg_arc_record *) (hist + 1
+ + sizeof (struct gmon_hist_hdr));
+
+ if (st.st_size == 0)
+ {
+ /* Create the signature. */
+ size_t cnt;
+
+ memcpy (addr, &gmon_hdr, sizeof (struct gmon_hdr));
+
+ *hist = GMON_TAG_TIME_HIST;
+ memcpy (hist + 1, &hist_hdr, sizeof (struct gmon_hist_hdr));
+
+ for (cnt = 0; cnt < param.fromssize / sizeof (*param.froms); ++cnt)
+ data[cnt].tag = GMON_TAG_CG_ARC;
+ }
+ else
+ {
+ /* Test the signature in the file. */
+ if (memcmp (addr, &gmon_hdr, sizeof (struct gmon_hdr)) != 0
+ || *hist != GMON_TAG_TIME_HIST
+ || memcmp (hist + 1, &hist_hdr, sizeof (struct gmon_hist_hdr)) != 0)
+ goto wrong_format;
+ }
+
+ /* Turn on profiling. */
+ param.state = GMON_PROF_ON;
+}
+
+
+void
+_dl_mcount (ElfW(Addr) frompc, ElfW(Addr) selfpc)
+{
+ if (param.state != GMON_PROF_ON)
+ return;
+ param.state = GMON_PROF_BUSY;
+
+ /* Compute relative addresses. The shared object can be loaded at
+ any address. The value of frompc could be anything. We cannot
+ restrict it in any way, just set to a fixed value (0) in case it
+ is outside the allowed range. These calls show up as calls from
+ <external> in the gprof output. */
+ frompc -= param.lowpc;
+ if (frompc >= param.textsize)
+ frompc = 0;
+ selfpc -= param.lowpc;
+
+ param.state = GMON_PROF_ON;
+}
diff --git a/elf/dl-reloc.c b/elf/dl-reloc.c
index 5b22a50..4f6eff8 100644
--- a/elf/dl-reloc.c
+++ b/elf/dl-reloc.c
@@ -24,6 +24,7 @@
#include <errno.h>
#include "dynamic-link.h"
+
void
_dl_relocate_object (struct link_map *l, struct link_map *scope[], int lazy)
{
@@ -65,7 +66,7 @@ _dl_relocate_object (struct link_map *l, struct link_map *scope[], int lazy)
l->l_name, (flags)))
#include "dynamic-link.h"
- ELF_DYNAMIC_RELOCATE (l, lazy);
+ ELF_DYNAMIC_RELOCATE (l, lazy, 1);
}
/* Mark the object so we know this work has been done. */
diff --git a/elf/dl-runtime.c b/elf/dl-runtime.c
index 7a44ea4..1b34026 100644
--- a/elf/dl-runtime.c
+++ b/elf/dl-runtime.c
@@ -137,17 +137,18 @@ fixup (
/* Perform the specified relocation. */
if (l->l_info[VERSYMIDX (DT_VERSYM)])
{
- const ElfW(Half) * version =
+ const ElfW(Half) *version =
(const ElfW(Half) *) (l->l_addr +
l->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
ElfW(Half) ndx = version[ELFW(R_SYM) (reloc->r_info)];
elf_machine_relplt (l, reloc, &symtab[ELFW(R_SYM) (reloc->r_info)],
- &l->l_versions[ndx]);
+ &l->l_versions[ndx],
+ (void *) (l->l_addr + reloc->r_offset));
}
else
elf_machine_relplt (l, reloc, &symtab[ELFW(R_SYM) (reloc->r_info)],
- NULL);
+ NULL, (void *) (l->l_addr + reloc->r_offset));
}
*_dl_global_scope_end = NULL;
@@ -161,6 +162,70 @@ fixup (
}
+#ifndef PROF
+static ElfW(Addr)
+profile_fixup (
+#ifdef ELF_MACHINE_RUNTIME_FIXUP_ARGS
+ ELF_MACHINE_RUNTIME_FIXUP_ARGS,
+#endif
+ struct link_map *l, ElfW(Word) reloc_offset, ElfW(Addr) retaddr)
+{
+ void (*mcount_fct) (ElfW(Addr), ElfW(Addr)) = _dl_mcount;
+ const ElfW(Sym) *const symtab
+ = (const ElfW(Sym) *) (l->l_addr + l->l_info[DT_SYMTAB]->d_un.d_ptr);
+ const char *strtab =
+ (const char *) (l->l_addr + l->l_info[DT_STRTAB]->d_un.d_ptr);
+
+ const PLTREL *const reloc
+ = (const void *) (l->l_addr + l->l_info[DT_JMPREL]->d_un.d_ptr +
+ reloc_offset);
+ ElfW(Addr) result;
+
+ /* Set up the scope to find symbols referenced by this object. */
+ struct link_map **scope = _dl_object_relocation_scope (l);
+
+ {
+ /* This macro is used as a callback from the elf_machine_relplt code. */
+#define RESOLVE(ref, version, flags) \
+ ((version) != NULL && (version)->hash != 0 \
+ ? _dl_lookup_versioned_symbol (strtab + (*ref)->st_name, (ref), scope, \
+ l->l_name, (version), (flags)) \
+ : _dl_lookup_symbol (strtab + (*ref)->st_name, (ref), scope, \
+ l->l_name, (flags)))
+#include "dynamic-link.h"
+
+ /* Perform the specified relocation. */
+ if (l->l_info[VERSYMIDX (DT_VERSYM)])
+ {
+ const ElfW(Half) *version =
+ (const ElfW(Half) *) (l->l_addr +
+ l->l_info[VERSYMIDX (DT_VERSYM)]->d_un.d_ptr);
+ ElfW(Half) ndx = version[ELFW(R_SYM) (reloc->r_info)];
+
+ elf_machine_relplt (l, reloc, &symtab[ELFW(R_SYM) (reloc->r_info)],
+ &l->l_versions[ndx], (void *) &result);
+ }
+ else
+ elf_machine_relplt (l, reloc, &symtab[ELFW(R_SYM) (reloc->r_info)],
+ NULL, (void *) &result);
+ }
+
+ *_dl_global_scope_end = NULL;
+
+ /* Return the address that was written by the relocation. */
+#ifdef ELF_FIXUP_RETURNS_ADDRESS
+ (*mcount_fct) (retaddr, result);
+
+ return &result; /* XXX This cannot work. What to do??? --drepper */
+#else
+ (*mcount_fct) (retaddr, result);
+
+ return result;
+#endif
+}
+#endif
+
+
/* This macro is defined in dl-machine.h to define the entry point called
by the PLT. The `fixup' function above does the real work, but a little
more twiddling is needed to get the stack right and jump to the address
diff --git a/elf/dl-support.c b/elf/dl-support.c
index 3333bf1..41997cc 100644
--- a/elf/dl-support.c
+++ b/elf/dl-support.c
@@ -42,6 +42,10 @@ int _dl_verbose;
/* Structure to store information about search paths. */
struct r_search_path *_dl_search_paths;
+/* We never do profiling. */
+const char *_dl_profile;
+struct link_map *_dl_profile_map;
+
static void non_dynamic_init (void) __attribute__ ((unused));
diff --git a/elf/do-rel.h b/elf/do-rel.h
index 766e62c..7f4b125 100644
--- a/elf/do-rel.h
+++ b/elf/do-rel.h
@@ -63,12 +63,14 @@ elf_dynamic_do_rel (struct link_map *map,
{
ElfW(Half) ndx = version[ELFW(R_SYM) (r->r_info)];
elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)],
- &map->l_versions[ndx]);
+ &map->l_versions[ndx],
+ (void *) (map->l_addr + r->r_offset));
}
}
else
for (; r < end; ++r)
- elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL);
+ elf_machine_rel (map, r, &symtab[ELFW(R_SYM) (r->r_info)], NULL,
+ (void *) (map->l_addr + r->r_offset));
}
}
diff --git a/elf/dynamic-link.h b/elf/dynamic-link.h
index 3377ee7..4a946f8 100644
--- a/elf/dynamic-link.h
+++ b/elf/dynamic-link.h
@@ -102,11 +102,14 @@ elf_get_dynamic_info (ElfW(Dyn) *dyn,
/* This can't just be an inline function because GCC is too dumb
to inline functions containing inlines themselves. */
-#define ELF_DYNAMIC_RELOCATE(map, lazy) \
- do { \
- int edr_lazy = elf_machine_runtime_setup((map), (lazy)); \
- ELF_DYNAMIC_DO_REL ((map), edr_lazy); \
- ELF_DYNAMIC_DO_RELA ((map), edr_lazy); \
+#define ELF_DYNAMIC_RELOCATE(map, lazy, consider_profile) \
+ do { \
+ int profile = (consider_profile && _dl_profile != NULL \
+ && _dl_name_match_p (_dl_profile, (map))); \
+ int edr_lazy = elf_machine_runtime_setup ((map), (lazy) || profile, \
+ profile); \
+ ELF_DYNAMIC_DO_REL ((map), edr_lazy); \
+ ELF_DYNAMIC_DO_RELA ((map), edr_lazy); \
} while (0)
#endif
diff --git a/elf/link.h b/elf/link.h
index e0fccd0..38a7c88 100644
--- a/elf/link.h
+++ b/elf/link.h
@@ -225,6 +225,11 @@ extern size_t _dl_pagesize;
/* File descriptor referring to the zero-fill device. */
extern int _dl_zerofd;
+/* Name of the shared object to be profiled (if any). */
+extern const char *_dl_profile;
+/* Map of shared object to be profiled. */
+extern struct link_map *_dl_profile_map;
+
/* OS-dependent function to open the zero-fill device. */
extern int _dl_sysdep_open_zero_fill (void); /* dl-sysdep.c */
@@ -430,8 +435,14 @@ extern void _dl_debug_state (void);
extern struct r_debug *_dl_debug_initialize (ElfW(Addr) ldbase);
/* Initialize the basic data structure for the search paths. */
-void _dl_init_paths (void);
+extern void _dl_init_paths (void);
+
+/* Gather the information needed to install the profiling tables and start
+ the timers. */
+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);
__END_DECLS
diff --git a/elf/rtld.c b/elf/rtld.c
index 7189ca6..726463c 100644
--- a/elf/rtld.c
+++ b/elf/rtld.c
@@ -61,6 +61,9 @@ int _dl_verbose;
const char *_dl_platform;
size_t _dl_platformlen;
struct r_search_path *_dl_search_paths;
+const char *_dl_profile;
+const char *_dl_profile_output;
+struct link_map *_dl_profile_map;
/* Set nonzero during loading and initialization of executable and
libraries, cleared before the executable's entry point runs. This
@@ -109,7 +112,7 @@ _dl_start (void *arg)
/* Relocate ourselves so we can do normal function calls and
data access using the global offset table. */
- ELF_DYNAMIC_RELOCATE (&bootstrap_map, 0);
+ ELF_DYNAMIC_RELOCATE (&bootstrap_map, 0, 0);
/* Now life is sane; we can call functions and access global data.
Set up to use the operating system facilities, and find out from
@@ -269,6 +272,26 @@ dl_main (const ElfW(Phdr) *phdr,
else
lazy = !__libc_enable_secure && *(getenv ("LD_BIND_NOW") ?: "") == '\0';
+ /* See whether we want to use profiling. */
+ _dl_profile = getenv ("LD_PROFILE");
+ if (_dl_profile != NULL)
+ if (_dl_profile[0] == '\0')
+ /* An empty string is of not much help. Disable profiling. */
+ _dl_profile = NULL;
+ else
+ {
+ /* OK, we have the name of a shared object we want to
+ profile. It's up to the user to provide a good name, it
+ must match the file name or soname of one of the loaded
+ objects. Now let's see where we are supposed to place the
+ result. */
+ _dl_profile_output = getenv ("LD_PROFILE_OUTPUT");
+
+ if (_dl_profile_output == NULL || _dl_profile_output[0] == '\0')
+ /* This is the default place. */
+ _dl_profile_output = "/var/tmp";
+ }
+
/* Set up a flag which tells we are just starting. */
_dl_starting_up = 1;
@@ -814,6 +837,11 @@ of this helper program; chances are you did not intend to run this program.\n",
_dl_debug_state ();
}
+ /* Now enable profiling if needed. */
+ if (_dl_profile_map != NULL)
+ /* We must prepare the profiling. */
+ _dl_start_profile (_dl_profile_map, _dl_profile_output);
+
/* Once we return, _dl_sysdep_start will invoke
the DT_INIT functions and then *USER_ENTRY. */
}
@@ -824,6 +852,8 @@ static void
print_unresolved (int errcode __attribute__ ((unused)), const char *objname,
const char *errstring)
{
+ if (objname[0] == '\0')
+ objname = _dl_argv[0] ?: "<main program>";
_dl_sysdep_error (errstring, " (", objname, ")\n", NULL);
}