Group :: Sistema/Base
RPM: glibc
Navegação
Main Changelog Spec Patches Sources Download Gear Bugs e FR Repocop
Patch: glibc-2.5-rh210130.patch
Download
Download
2006-10-18 Ulrich Drepper <drepper@redhat.com>
* elf/dl-lookup.c (_dl_lookup_symbol_x): Add warning to
_dl_lookup_symbol_x code.
2006-10-17 Jakub Jelinek <jakub@redhat.com>
* elf/dl-runtime.c: Include sysdep-cancel.h.
(_dl_fixup, _dl_profile_fixup): Use __rtld_mrlock_* and
scoperec->nusers only if !SINGLE_THREAD_P. Use atomic_*
instead of catomic_* macros.
* elf/dl-sym.c: Include sysdep-cancel.h.
(do_sym): Use __rtld_mrlock_* and scoperec->nusers only
if !SINGLE_THREAD_P. Use atomic_* instead of catomic_* macros.
* elf/dl-close.c: Include sysdep-cancel.h.
(_dl_close): Use __rtld_mrlock_* and scoperec->nusers only
if !SINGLE_THREAD_P. Use atomic_* instead of catomic_* macros.
* elf/dl-open.c: Include sysdep-cancel.h.
(dl_open_worker): Use __rtld_mrlock_* and scoperec->nusers only
if !SINGLE_THREAD_P. Use atomic_* instead of catomic_* macros.
2006-10-09 Ulrich Drepper <drepper@redhat.com>
Jakub Jelinek <jakub@redhat.com>
Implement reference counting of scope records.
* elf/dl-close.c (_dl_close): Remove all scopes from removed objects
from the list in objects which remain. Always allocate new scope
record.
* elf/dl-open.c (dl_open_worker): When growing array for scopes,
don't resize, allocate a new one.
* elf/dl-runtime.c: Update reference counters before using a scope
array.
* elf/dl-sym.c: Likewise.
* elf/dl-libc.c: Adjust for l_scope name change.
* elf/dl-load.c: Likewise.
* elf/dl-object.c: Likewise.
* elf/rtld.c: Likewise.
* include/link.h: Include <rtld-lowlevel.h>. Define struct
r_scoperec. Replace r_scope with pointer to r_scoperec structure.
Add l_scoperec_lock.
* sysdeps/generic/ldsodefs.h: Include <rtld-lowlevel.h>.
* sysdeps/generic/rtld-lowlevel.h: New file.
nptl/
2006-10-17 Jakub Jelinek <jakub@redhat.com>
* sysdeps/unix/sysv/linux/rtld-lowlevel.h (__rtld_mrlock_lock,
__rtld_mrlock_unlock, __rtld_mrlock_change, __rtld_mrlock_done): Use
atomic_* instead of catomic_* macros.
2006-10-11 Ulrich Drepper <drepper@redhat.com>
* sysdeps/unix/sysv/linux/rtld-lowlevel.h: Use catomic_*
operations instead of atomic_*.
2006-10-09 Ulrich Drepper <drepper@redhat.com>
* sysdeps/unix/sysv/linux/rtld-lowlevel.h: New file..
--- libc/elf/dl-close.c 19 Sep 2006 14:39:42 -0000 1.117
+++ libc/elf/dl-close.c 18 Oct 2006 19:19:07 -0000 1.120
@@ -19,6 +19,7 @@
#include <assert.h>
#include <dlfcn.h>
+#include <errno.h>
#include <libintl.h>
#include <stddef.h>
#include <stdio.h>
@@ -29,12 +30,17 @@
#include <ldsodefs.h>
#include <sys/types.h>
#include <sys/mman.h>
+#include <sysdep-cancel.h>
/* Type of the constructor functions. */
typedef void (*fini_t) (void);
+/* Special l_idx value used to indicate which objects remain loaded. */
+#define IDX_STILL_USED -1
+
+
#ifdef USE_TLS
/* Returns true we an non-empty was found. */
static bool
@@ -188,7 +194,7 @@ _dl_close (void *_map)
done[done_index] = 1;
used[done_index] = 1;
/* Signal the object is still needed. */
- l->l_idx = -1;
+ l->l_idx = IDX_STILL_USED;
/* Mark all dependencies as used. */
if (l->l_initfini != NULL)
@@ -196,7 +202,7 @@ _dl_close (void *_map)
struct link_map **lp = &l->l_initfini[1];
while (*lp != NULL)
{- if ((*lp)->l_idx != -1)
+ if ((*lp)->l_idx != IDX_STILL_USED)
{assert ((*lp)->l_idx >= 0 && (*lp)->l_idx < nloaded);
@@ -217,7 +223,7 @@ _dl_close (void *_map)
{struct link_map *jmap = l->l_reldeps[j];
- if (jmap->l_idx != -1)
+ if (jmap->l_idx != IDX_STILL_USED)
{assert (jmap->l_idx >= 0 && jmap->l_idx < nloaded);
@@ -310,8 +316,9 @@ _dl_close (void *_map)
/* Else used[i]. */
else if (imap->l_type == lt_loaded)
{- if (imap->l_searchlist.r_list == NULL
- && imap->l_initfini != NULL)
+ struct r_scope_elem *new_list = NULL;
+
+ if (imap->l_searchlist.r_list == NULL && imap->l_initfini != NULL)
{/* The object is still used. But one of the objects we are
unloading right now is responsible for loading it. If
@@ -328,44 +335,119 @@ _dl_close (void *_map)
imap->l_searchlist.r_list = &imap->l_initfini[cnt + 1];
imap->l_searchlist.r_nlist = cnt;
- for (cnt = 0; imap->l_scope[cnt] != NULL; ++cnt)
- /* This relies on l_scope[] entries being always set either
- to its own l_symbolic_searchlist address, or some map's
- l_searchlist address. */
- if (imap->l_scope[cnt] != &imap->l_symbolic_searchlist)
- {- struct link_map *tmap;
-
- tmap = (struct link_map *) ((char *) imap->l_scope[cnt]
- - offsetof (struct link_map,
- l_searchlist));
- assert (tmap->l_ns == ns);
- if (tmap->l_idx != -1)
- {- imap->l_scope[cnt] = &imap->l_searchlist;
- break;
- }
- }
+ new_list = &imap->l_searchlist;
}
- else
+
+ /* Count the number of scopes which remain after the unload.
+ When we add the local search list count it. Always add
+ one for the terminating NULL pointer. */
+ size_t remain = (new_list != NULL) + 1;
+ bool removed_any = false;
+ for (size_t cnt = 0; imap->l_scoperec->scope[cnt] != NULL; ++cnt)
+ /* This relies on l_scope[] entries being always set either
+ to its own l_symbolic_searchlist address, or some map's
+ l_searchlist address. */
+ if (imap->l_scoperec->scope[cnt] != &imap->l_symbolic_searchlist)
+ {+ struct link_map *tmap = (struct link_map *)
+ ((char *) imap->l_scoperec->scope[cnt]
+ - offsetof (struct link_map, l_searchlist));
+ assert (tmap->l_ns == ns);
+ if (tmap->l_idx == IDX_STILL_USED)
+ ++remain;
+ else
+ removed_any = true;
+ }
+ else
+ ++remain;
+
+ if (removed_any)
{- unsigned int cnt = 0;
- while (imap->l_scope[cnt] != NULL)
+ /* Always allocate a new array for the scope. This is
+ necessary since we must be able to determine the last
+ user of the current array. If possible use the link map's
+ memory. */
+ size_t new_size;
+ struct r_scoperec *newp;
+ if (imap->l_scoperec != &imap->l_scoperec_mem
+ && remain < NINIT_SCOPE_ELEMS (imap)
+ && imap->l_scoperec_mem.nusers == 0)
+ {+ new_size = NINIT_SCOPE_ELEMS (imap);
+ newp = &imap->l_scoperec_mem;
+ }
+ else
+ {+ new_size = imap->l_scope_max;
+ newp = (struct r_scoperec *)
+ malloc (sizeof (struct r_scoperec)
+ + new_size * sizeof (struct r_scope_elem *));
+ if (newp == NULL)
+ _dl_signal_error (ENOMEM, "dlclose", NULL,
+ N_("cannot create scope list"));+ }
+
+ newp->nusers = 0;
+ newp->remove_after_use = false;
+ newp->notify = false;
+
+ /* Copy over the remaining scope elements. */
+ remain = 0;
+ for (size_t cnt = 0; imap->l_scoperec->scope[cnt] != NULL; ++cnt)
+ {+ if (imap->l_scoperec->scope[cnt]
+ != &imap->l_symbolic_searchlist)
+ {+ struct link_map *tmap = (struct link_map *)
+ ((char *) imap->l_scoperec->scope[cnt]
+ - offsetof (struct link_map, l_searchlist));
+ if (tmap->l_idx != IDX_STILL_USED)
+ {+ /* Remove the scope. Or replace with own map's
+ scope. */
+ if (new_list != NULL)
+ {+ newp->scope[remain++] = new_list;
+ new_list = NULL;
+ }
+ continue;
+ }
+ }
+
+ newp->scope[remain++] = imap->l_scoperec->scope[cnt];
+ }
+ newp->scope[remain] = NULL;
+
+ struct r_scoperec *old = imap->l_scoperec;
+
+ if (SINGLE_THREAD_P)
+ imap->l_scoperec = newp;
+ else
{- if (imap->l_scope[cnt] == &map->l_searchlist)
+ __rtld_mrlock_change (imap->l_scoperec_lock);
+ imap->l_scoperec = newp;
+ __rtld_mrlock_done (imap->l_scoperec_lock);
+
+ if (atomic_increment_val (&old->nusers) != 1)
{- while ((imap->l_scope[cnt] = imap->l_scope[cnt + 1])
- != NULL)
- ++cnt;
- break;
+ old->remove_after_use = true;
+ old->notify = true;
+ if (atomic_decrement_val (&old->nusers) != 0)
+ __rtld_waitzero (old->nusers);
}
- ++cnt;
}
+
+ /* No user anymore, we can free it now. */
+ if (old != &imap->l_scoperec_mem)
+ free (old);
+
+ imap->l_scope_max = new_size;
}
/* The loader is gone, so mark the object as not having one.
- Note: l_idx != -1 -> object will be removed. */
- if (imap->l_loader != NULL && imap->l_loader->l_idx != -1)
+ Note: l_idx != IDX_STILL_USED -> object will be removed. */
+ if (imap->l_loader != NULL
+ && imap->l_loader->l_idx != IDX_STILL_USED)
imap->l_loader = NULL;
/* Remember where the first dynamically loaded object is. */
@@ -570,8 +652,8 @@ _dl_close (void *_map)
free (imap->l_initfini);
/* Remove the scope array if we allocated it. */
- if (imap->l_scope != imap->l_scope_mem)
- free (imap->l_scope);
+ if (imap->l_scoperec != &imap->l_scoperec_mem)
+ free (imap->l_scoperec);
if (imap->l_phdr_allocated)
free ((void *) imap->l_phdr);
--- libc/elf/dl-libc.c 12 Jun 2005 16:28:48 -0000 1.26
+++ libc/elf/dl-libc.c 10 Oct 2006 00:49:56 -0000 1.27
@@ -133,7 +133,8 @@ do_dlsym_private (void *ptr)
struct do_dlsym_args *args = (struct do_dlsym_args *) ptr;
args->ref = NULL;
l = GLRO(dl_lookup_symbol_x) (args->name, args->map, &args->ref,
- args->map->l_scope, &vers, 0, 0, NULL);
+ args->map->l_scoperec->scope, &vers, 0, 0,
+ NULL);
args->loadbase = l;
}
--- libc/elf/dl-load.c 29 Aug 2006 01:43:42 -0000 1.279
+++ libc/elf/dl-load.c 10 Oct 2006 00:49:56 -0000 1.280
@@ -1473,7 +1473,7 @@ cannot enable executable stack as shared
have to do this for the main map. */
if ((mode & RTLD_DEEPBIND) == 0
&& __builtin_expect (l->l_info[DT_SYMBOLIC] != NULL, 0)
- && &l->l_searchlist != l->l_scope[0])
+ && &l->l_searchlist != l->l_scoperec->scope[0])
{/* Create an appropriate searchlist. It contains only this map.
This is the definition of DT_SYMBOLIC in SysVr4. */
@@ -1490,11 +1490,11 @@ cannot enable executable stack as shared
l->l_symbolic_searchlist.r_nlist = 1;
/* Now move the existing entries one back. */
- memmove (&l->l_scope[1], &l->l_scope[0],
- (l->l_scope_max - 1) * sizeof (l->l_scope[0]));
+ memmove (&l->l_scoperec->scope[1], &l->l_scoperec->scope[0],
+ (l->l_scope_max - 1) * sizeof (l->l_scoperec->scope[0]));
/* Now add the new entry. */
- l->l_scope[0] = &l->l_symbolic_searchlist;
+ l->l_scoperec->scope[0] = &l->l_symbolic_searchlist;
}
/* Remember whether this object must be initialized first. */
--- libc/elf/dl-lookup.c 10 Jul 2006 21:49:38 -0000 1.122
+++ libc/elf/dl-lookup.c 18 Oct 2006 19:11:33 -0000 1.123
@@ -207,7 +207,11 @@ _dl_debug_bindings (const char *undef_na
/* Search loaded objects' symbol tables for a definition of the symbol
- UNDEF_NAME, perhaps with a requested version for the symbol. */
+ UNDEF_NAME, perhaps with a requested version for the symbol.
+
+ We must never have calls to the audit functions inside this function
+ or in any function which gets called. If this would happen the audit
+ code might create a thread which can throw off all the scope locking. */
lookup_t
internal_function
_dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
--- libc/elf/dl-object.c 6 Jan 2005 22:40:26 -0000 1.40
+++ libc/elf/dl-object.c 10 Oct 2006 00:49:56 -0000 1.41
@@ -82,8 +82,14 @@ _dl_new_object (char *realname, const ch
/* Use the 'l_scope_mem' array by default for the the 'l_scope'
information. If we need more entries we will allocate a large
array dynamically. */
- new->l_scope = new->l_scope_mem;
- new->l_scope_max = sizeof (new->l_scope_mem) / sizeof (new->l_scope_mem[0]);
+ new->l_scoperec = &new->l_scoperec_mem;
+ new->l_scope_max = (sizeof (new->l_scope_realmem.scope_elems)
+ / sizeof (new->l_scope_realmem.scope_elems[0]));
+
+ /* No need to initialize the scope lock if the initializer is zero. */
+#if _RTLD_MRLOCK_INITIALIZER != 0
+ __rtld_mrlock_initialize (new->l_scoperec_mem.lock);
+#endif
/* Counter for the scopes we have to handle. */
idx = 0;
@@ -98,7 +104,8 @@ _dl_new_object (char *realname, const ch
l->l_next = new;
/* Add the global scope. */
- new->l_scope[idx++] = &GL(dl_ns)[nsid]._ns_loaded->l_searchlist;
+ new->l_scoperec->scope[idx++]
+ = &GL(dl_ns)[nsid]._ns_loaded->l_searchlist;
}
else
GL(dl_ns)[nsid]._ns_loaded = new;
@@ -114,15 +121,15 @@ _dl_new_object (char *realname, const ch
loader = loader->l_loader;
/* Insert the scope if it isn't the global scope we already added. */
- if (idx == 0 || &loader->l_searchlist != new->l_scope[0])
+ if (idx == 0 || &loader->l_searchlist != new->l_scoperec->scope[0])
{if ((mode & RTLD_DEEPBIND) != 0 && idx != 0)
{- new->l_scope[1] = new->l_scope[0];
+ new->l_scoperec->scope[1] = new->l_scoperec->scope[0];
idx = 0;
}
- new->l_scope[idx] = &loader->l_searchlist;
+ new->l_scoperec->scope[idx] = &loader->l_searchlist;
}
new->l_local_scope[0] = &new->l_searchlist;
--- libc/elf/dl-open.c 28 Aug 2006 22:56:50 -0000 1.128
+++ libc/elf/dl-open.c 18 Oct 2006 19:20:13 -0000 1.131
@@ -31,6 +31,7 @@
#include <ldsodefs.h>
#include <bp-sym.h>
#include <caller.h>
+#include <sysdep-cancel.h>
#include <dl-dst.h>
@@ -343,7 +344,7 @@ dl_open_worker (void *a)
start the profiling. */
struct link_map *old_profile_map = GL(dl_profile_map);
- _dl_relocate_object (l, l->l_scope, 1, 1);
+ _dl_relocate_object (l, l->l_scoperec->scope, 1, 1);
if (old_profile_map == NULL && GL(dl_profile_map) != NULL)
{@@ -356,7 +357,7 @@ dl_open_worker (void *a)
}
else
#endif
- _dl_relocate_object (l, l->l_scope, lazy, 0);
+ _dl_relocate_object (l, l->l_scoperec->scope, lazy, 0);
}
if (l == new)
@@ -374,11 +375,13 @@ dl_open_worker (void *a)
not been loaded here and now. */
if (imap->l_init_called && imap->l_type == lt_loaded)
{- struct r_scope_elem **runp = imap->l_scope;
+ struct r_scope_elem **runp = imap->l_scoperec->scope;
size_t cnt = 0;
while (*runp != NULL)
{+ if (*runp == &new->l_searchlist)
+ break;
++cnt;
++runp;
}
@@ -391,35 +394,63 @@ dl_open_worker (void *a)
{/* The 'r_scope' array is too small. Allocate a new one
dynamically. */
- struct r_scope_elem **newp;
- size_t new_size = imap->l_scope_max * 2;
+ size_t new_size;
+ struct r_scoperec *newp;
- if (imap->l_scope == imap->l_scope_mem)
+ if (imap->l_scoperec != &imap->l_scoperec_mem
+ && imap->l_scope_max < NINIT_SCOPE_ELEMS (imap)
+ && imap->l_scoperec_mem.nusers == 0)
{- newp = (struct r_scope_elem **)
- malloc (new_size * sizeof (struct r_scope_elem *));
- if (newp == NULL)
- _dl_signal_error (ENOMEM, "dlopen", NULL,
- N_("cannot create scope list"));- imap->l_scope = memcpy (newp, imap->l_scope,
- cnt * sizeof (imap->l_scope[0]));
+ new_size = NINIT_SCOPE_ELEMS (imap);
+ newp = &imap->l_scoperec_mem;
}
else
{- newp = (struct r_scope_elem **)
- realloc (imap->l_scope,
- new_size * sizeof (struct r_scope_elem *));
+ new_size = imap->l_scope_max * 2;
+ newp = (struct r_scoperec *)
+ malloc (sizeof (struct r_scoperec)
+ + new_size * sizeof (struct r_scope_elem *));
if (newp == NULL)
_dl_signal_error (ENOMEM, "dlopen", NULL,
N_("cannot create scope list"));- imap->l_scope = newp;
+ }
+
+ newp->nusers = 0;
+ newp->remove_after_use = false;
+ newp->notify = false;
+ memcpy (newp->scope, imap->l_scoperec->scope,
+ cnt * sizeof (imap->l_scoperec->scope[0]));
+ struct r_scoperec *old = imap->l_scoperec;
+
+ if (old == &imap->l_scoperec_mem)
+ imap->l_scoperec = newp;
+ else if (SINGLE_THREAD_P)
+ {+ imap->l_scoperec = newp;
+ free (old);
+ }
+ else
+ {+ __rtld_mrlock_change (imap->l_scoperec_lock);
+ imap->l_scoperec = newp;
+ __rtld_mrlock_done (imap->l_scoperec_lock);
+
+ atomic_increment (&old->nusers);
+ old->remove_after_use = true;
+ if (atomic_decrement_val (&old->nusers) == 0)
+ /* No user, we can free it here and now. */
+ free (old);
}
imap->l_scope_max = new_size;
}
- imap->l_scope[cnt++] = &new->l_searchlist;
- imap->l_scope[cnt] = NULL;
+ /* First terminate the extended list. Otherwise a thread
+ might use the new last element and then use the garbage
+ at offset IDX+1. */
+ imap->l_scoperec->scope[cnt + 1] = NULL;
+ atomic_write_barrier ();
+ imap->l_scoperec->scope[cnt] = &new->l_searchlist;
}
#if USE_TLS
/* Only add TLS memory if this object is loaded now and
--- libc/elf/dl-runtime.c 7 Feb 2005 22:47:00 -0000 1.69
+++ libc/elf/dl-runtime.c 18 Oct 2006 19:16:52 -0000 1.72
@@ -24,6 +24,7 @@
#include <unistd.h>
#include <sys/param.h>
#include <ldsodefs.h>
+#include <sysdep-cancel.h>
#include "dynamic-link.h"
#if (!defined ELF_MACHINE_NO_RELA && !defined ELF_MACHINE_PLT_REL) \
@@ -92,16 +93,36 @@ _dl_fixup (
version = NULL;
}
+ struct r_scoperec *scoperec = l->l_scoperec;
+ if (l->l_type == lt_loaded && !SINGLE_THREAD_P)
+ {+ __rtld_mrlock_lock (l->l_scoperec_lock);
+ scoperec = l->l_scoperec;
+ atomic_increment (&scoperec->nusers);
+ __rtld_mrlock_unlock (l->l_scoperec_lock);
+ }
+
result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym,
- l->l_scope, version, ELF_RTYPE_CLASS_PLT,
+ scoperec->scope, version,
+ ELF_RTYPE_CLASS_PLT,
DL_LOOKUP_ADD_DEPENDENCY, NULL);
+ if (l->l_type == lt_loaded && !SINGLE_THREAD_P
+ && atomic_decrement_val (&scoperec->nusers) == 0
+ && __builtin_expect (scoperec->remove_after_use, 0))
+ {+ if (scoperec->notify)
+ __rtld_notify (scoperec->nusers);
+ else
+ free (scoperec);
+ }
+
/* Currently result contains the base load address (or link map)
of the object that defines sym. Now add in the symbol
offset. */
value = DL_FIXUP_MAKE_VALUE (result,
- sym ? LOOKUP_VALUE_ADDRESS (result)
- + sym->st_value : 0);
+ sym ? (LOOKUP_VALUE_ADDRESS (result)
+ + sym->st_value) : 0);
}
else
{@@ -174,11 +195,30 @@ _dl_profile_fixup (
version = NULL;
}
+ struct r_scoperec *scoperec = l->l_scoperec;
+ if (l->l_type == lt_loaded && !SINGLE_THREAD_P)
+ {+ __rtld_mrlock_lock (l->l_scoperec_lock);
+ scoperec = l->l_scoperec;
+ atomic_increment (&scoperec->nusers);
+ __rtld_mrlock_unlock (l->l_scoperec_lock);
+ }
+
result = _dl_lookup_symbol_x (strtab + refsym->st_name, l, &defsym,
- l->l_scope, version,
+ scoperec->scope, version,
ELF_RTYPE_CLASS_PLT,
DL_LOOKUP_ADD_DEPENDENCY, NULL);
+ if (l->l_type == lt_loaded && !SINGLE_THREAD_P
+ && atomic_decrement_val (&scoperec->nusers) == 0
+ && __builtin_expect (scoperec->remove_after_use, 0))
+ {+ if (scoperec->notify)
+ __rtld_notify (scoperec->nusers);
+ else
+ free (scoperec);
+ }
+
/* Currently result contains the base load address (or link map)
of the object that defines sym. Now add in the symbol
offset. */
--- libc/elf/dl-sym.c 26 Feb 2006 20:48:48 -0000 1.27
+++ libc/elf/dl-sym.c 18 Oct 2006 19:18:11 -0000 1.30
@@ -17,6 +17,7 @@
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
+#include <assert.h>
#include <stddef.h>
#include <setjmp.h>
#include <libintl.h>
@@ -24,6 +25,7 @@
#include <dlfcn.h>
#include <ldsodefs.h>
#include <dl-hash.h>
+#include <sysdep-cancel.h>
#ifdef USE_TLS
# include <dl-tls.h>
#endif
@@ -58,6 +60,30 @@ _dl_tls_symaddr (struct link_map *map, c
#endif
+struct call_dl_lookup_args
+{+ /* Arguments to do_dlsym. */
+ struct link_map *map;
+ const char *name;
+ struct r_scope_elem **scope;
+ struct r_found_version *vers;
+ int flags;
+
+ /* Return values of do_dlsym. */
+ lookup_t loadbase;
+ const ElfW(Sym) **refp;
+};
+
+static void
+call_dl_lookup (void *ptr)
+{+ struct call_dl_lookup_args *args = (struct call_dl_lookup_args *) ptr;
+ args->map = GLRO(dl_lookup_symbol_x) (args->name, args->map, args->refp,
+ args->scope, args->vers, 0,
+ args->flags, NULL);
+}
+
+
static void *
internal_function
do_sym (void *handle, const char *name, void *who,
@@ -84,10 +110,62 @@ do_sym (void *handle, const char *name,
}
if (handle == RTLD_DEFAULT)
- /* Search the global scope. */
- result = GLRO(dl_lookup_symbol_x) (name, match, &ref, match->l_scope,
- vers, 0, flags|DL_LOOKUP_ADD_DEPENDENCY,
- NULL);
+ {+ /* Search the global scope. We have the simple case where
+ we look up in the scope of an object which was part of
+ the initial binary. And then the more complex part
+ where the object is dynamically loaded and the scope
+ array can change. */
+ if (match->l_type != lt_loaded || SINGLE_THREAD_P)
+ result = GLRO(dl_lookup_symbol_x) (name, match, &ref,
+ match->l_scoperec->scope, vers, 0,
+ flags | DL_LOOKUP_ADD_DEPENDENCY,
+ NULL);
+ else
+ {+ __rtld_mrlock_lock (match->l_scoperec_lock);
+ struct r_scoperec *scoperec = match->l_scoperec;
+ atomic_increment (&scoperec->nusers);
+ __rtld_mrlock_unlock (match->l_scoperec_lock);
+
+ struct call_dl_lookup_args args;
+ args.name = name;
+ args.map = match;
+ args.scope = scoperec->scope;
+ args.vers = vers;
+ args.flags = flags | DL_LOOKUP_ADD_DEPENDENCY;
+ args.refp = &ref;
+
+ const char *objname;
+ const char *errstring = NULL;
+ bool malloced;
+ int err = GLRO(dl_catch_error) (&objname, &errstring, &malloced,
+ call_dl_lookup, &args);
+
+ if (atomic_decrement_val (&scoperec->nusers) == 0
+ && __builtin_expect (scoperec->remove_after_use, 0))
+ {+ if (scoperec->notify)
+ __rtld_notify (scoperec->nusers);
+ else
+ free (scoperec);
+ }
+
+ if (__builtin_expect (errstring != NULL, 0))
+ {+ /* The lookup was unsuccessful. Rethrow the error. */
+ char *errstring_dup = strdupa (errstring);
+ char *objname_dup = strdupa (objname);
+ if (malloced)
+ free ((char *) errstring);
+
+ GLRO(dl_signal_error) (err, objname_dup, NULL, errstring_dup);
+ /* NOTREACHED */
+ }
+
+ result = args.map;
+ }
+ }
else if (handle == RTLD_NEXT)
{if (__builtin_expect (match == GL(dl_ns)[LM_ID_BASE]._ns_loaded, 0))
--- libc/elf/rtld.c 2 Oct 2006 18:24:37 -0000 1.364
+++ libc/elf/rtld.c 10 Oct 2006 00:49:56 -0000 1.365
@@ -609,7 +609,7 @@ relocate_doit (void *a)
{struct relocate_args *args = (struct relocate_args *) a;
- _dl_relocate_object (args->l, args->l->l_scope, args->lazy, 0);
+ _dl_relocate_object (args->l, args->l->l_scoperec->scope, args->lazy, 0);
}
static void
@@ -1963,8 +1963,8 @@ ERROR: ld.so: object '%s' cannot be load
lookup_t result;
result = _dl_lookup_symbol_x (INTUSE(_dl_argv)[i], main_map,
- &ref, main_map->l_scope, NULL,
- ELF_RTYPE_CLASS_PLT,
+ &ref, main_map->l_scoperec->scope,
+ NULL, ELF_RTYPE_CLASS_PLT,
DL_LOOKUP_ADD_DEPENDENCY, NULL);
loadbase = LOOKUP_VALUE_ADDRESS (result);
@@ -2006,8 +2006,8 @@ ERROR: ld.so: object '%s' cannot be load
{/* Mark the link map as not yet relocated again. */
GL(dl_rtld_map).l_relocated = 0;
- _dl_relocate_object (&GL(dl_rtld_map), main_map->l_scope,
- 0, 0);
+ _dl_relocate_object (&GL(dl_rtld_map),
+ main_map->l_scoperec->scope, 0, 0);
}
}
#define VERNEEDTAG (DT_NUM + DT_THISPROCNUM + DT_VERSIONTAGIDX (DT_VERNEED))
@@ -2227,7 +2227,7 @@ ERROR: ld.so: object '%s' cannot be load
}
if (l != &GL(dl_rtld_map))
- _dl_relocate_object (l, l->l_scope, GLRO(dl_lazy),
+ _dl_relocate_object (l, l->l_scoperec->scope, GLRO(dl_lazy),
consider_profiling);
#ifdef USE_TLS
@@ -2303,7 +2303,8 @@ ERROR: ld.so: object '%s' cannot be load
HP_TIMING_NOW (start);
/* Mark the link map as not yet relocated again. */
GL(dl_rtld_map).l_relocated = 0;
- _dl_relocate_object (&GL(dl_rtld_map), main_map->l_scope, 0, 0);
+ _dl_relocate_object (&GL(dl_rtld_map), main_map->l_scoperec->scope,
+ 0, 0);
HP_TIMING_NOW (stop);
HP_TIMING_DIFF (add, start, stop);
HP_TIMING_ACCUM_NT (relocate_time, add);
--- libc/include/link.h 20 Sep 2006 20:28:55 -0000 1.40
+++ libc/include/link.h 10 Oct 2006 00:39:30 -0000 1.41
@@ -43,6 +43,8 @@ extern unsigned int la_objopen (struct l
#include <bits/linkmap.h>
#include <dl-lookupcfg.h>
#include <tls.h> /* Defines USE_TLS. */
+#include <bits/libc-lock.h>
+#include <rtld-lowlevel.h>
/* Some internal data structures of the dynamic linker used in the
@@ -73,6 +75,18 @@ struct r_search_path_struct
};
+/* Structure for a scope. Each such data structure has a lock. The
+ lock allows many readers. It can be invalidated by setting bit 31
+ which means that no more lockers are allowe */
+struct r_scoperec
+{+ bool remove_after_use;
+ bool notify;
+ int nusers;
+ struct r_scope_elem *scope[0];
+};
+
+
/* Structure describing a loaded shared object. The `l_next' and `l_prev'
members form a chain of all the shared objects loaded at startup.
@@ -212,12 +226,27 @@ struct link_map
ElfW(Addr) l_text_end;
/* Default array for 'l_scope'. */
- struct r_scope_elem *l_scope_mem[4];
+ union
+ {+ struct r_scoperec l_scoperec_mem;
+ struct
+ {+ struct r_scoperec scoperec_struct;
+ /* XXX This number should be increased once the scope memory
+ handling has been tested. */
+ struct r_scope_elem *scope_elems[4];
+#define NINIT_SCOPE_ELEMS(map) \
+ (sizeof ((map)->l_scope_realmem.scope_elems) \
+ / sizeof ((map)->l_scope_realmem.scope_elems[0]))
+ } l_scope_realmem;
+ };
/* Size of array allocated for 'l_scope'. */
size_t l_scope_max;
/* This is an array defining the lookup scope for this link map.
There are initially at most three different scope lists. */
- struct r_scope_elem **l_scope;
+ struct r_scoperec *l_scoperec;
+ /* We need to protect using the SCOPEREC. */
+ __rtld_mrlock_define (, l_scoperec_lock)
/* A similar array, this time only with the local scope. This is
used occasionally. */
--- libc/nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h 1 Jan 1970 00:00:00 -0000
+++ libc/nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h 18 Oct 2006 19:14:38 -0000 1.4
@@ -0,0 +1,151 @@
+/* Defintions for lowlevel handling in ld.so.
+ Copyright (C) 2006 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
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#ifndef _RTLD_LOWLEVEL_H
+#define _RTLD_LOWLEVEL_H 1
+
+#include <atomic.h>
+#include <lowlevellock.h>
+
+
+/* Special multi-reader lock used in ld.so. */
+#define __RTLD_MRLOCK_WRITER 1
+#define __RTLD_MRLOCK_RWAIT 2
+#define __RTLD_MRLOCK_WWAIT 4
+#define __RTLD_MRLOCK_RBITS \
+ ~(__RTLD_MRLOCK_WRITER | __RTLD_MRLOCK_RWAIT | __RTLD_MRLOCK_WWAIT)
+#define __RTLD_MRLOCK_INC 8
+#define __RTLD_MRLOCK_TRIES 5
+
+
+typedef int __rtld_mrlock_t;
+
+
+#define __rtld_mrlock_define(CLASS,NAME) \
+ CLASS __rtld_mrlock_t NAME;
+
+
+#define _RTLD_MRLOCK_INITIALIZER 0
+#define __rtld_mrlock_initialize(NAME) \
+ (void) ((NAME) = 0
+
+
+#define __rtld_mrlock_lock(lock) \
+ do { \+ __label__ out; \
+ while (1) \
+ { \+ int oldval; \
+ for (int tries = 0; tries < __RTLD_MRLOCK_TRIES; ++tries) \
+ { \+ oldval = lock; \
+ while (__builtin_expect ((oldval \
+ & (__RTLD_MRLOCK_WRITER \
+ | __RTLD_MRLOCK_WWAIT)) \
+ == 0, 1)) \
+ { \+ int newval = ((oldval & __RTLD_MRLOCK_RBITS) \
+ + __RTLD_MRLOCK_INC); \
+ int ret = atomic_compare_and_exchange_val_acq (&(lock), \
+ newval, \
+ oldval); \
+ if (__builtin_expect (ret == oldval, 1)) \
+ goto out; \
+ } \
+ atomic_delay (); \
+ } \
+ if ((oldval & __RTLD_MRLOCK_RWAIT) == 0) \
+ { \+ atomic_or (&(lock), __RTLD_MRLOCK_RWAIT); \
+ oldval |= __RTLD_MRLOCK_RWAIT; \
+ } \
+ lll_futex_wait (lock, oldval); \
+ } \
+ out:; \
+ } while (0)
+
+
+#define __rtld_mrlock_unlock(lock) \
+ do { \+ int oldval = atomic_exchange_and_add (&(lock), -__RTLD_MRLOCK_INC); \
+ if (__builtin_expect ((oldval \
+ & (__RTLD_MRLOCK_RBITS | __RTLD_MRLOCK_WWAIT)) \
+ == (__RTLD_MRLOCK_INC | __RTLD_MRLOCK_WWAIT), 0)) \
+ /* We have to wake all threads since there might be some queued \
+ readers already. */ \
+ lll_futex_wake (&(lock), 0x7fffffff); \
+ } while (0)
+
+
+/* There can only ever be one thread trying to get the exclusive lock. */
+#define __rtld_mrlock_change(lock) \
+ do { \+ __label__ out; \
+ while (1) \
+ { \+ int oldval; \
+ for (int tries = 0; tries < __RTLD_MRLOCK_TRIES; ++tries) \
+ { \+ oldval = lock; \
+ while (__builtin_expect ((oldval & __RTLD_MRLOCK_RBITS) == 0, 1)) \
+ { \+ int newval = ((oldval & __RTLD_MRLOCK_RWAIT) \
+ + __RTLD_MRLOCK_WRITER); \
+ int ret = atomic_compare_and_exchange_val_acq (&(lock), \
+ newval, \
+ oldval); \
+ if (__builtin_expect (ret == oldval, 1)) \
+ goto out; \
+ } \
+ atomic_delay (); \
+ } \
+ atomic_or (&(lock), __RTLD_MRLOCK_WWAIT); \
+ oldval |= __RTLD_MRLOCK_WWAIT; \
+ lll_futex_wait (lock, oldval); \
+ } \
+ out:; \
+ } while (0)
+
+
+#define __rtld_mrlock_done(lock) \
+ do { \+ int oldval = atomic_exchange_and_add (&(lock), -__RTLD_MRLOCK_WRITER); \
+ if (__builtin_expect ((oldval & __RTLD_MRLOCK_RWAIT) != 0, 0)) \
+ lll_futex_wake (&(lock), 0x7fffffff); \
+ } while (0)
+
+
+/* Function to wait for variable become zero. Used in ld.so for
+ reference counters. */
+#define __rtld_waitzero(word) \
+ do { \+ while (1) \
+ { \+ int val = word; \
+ if (val == 0) \
+ break; \
+ lll_futex_wait (&(word), val); \
+ } \
+ } while (0)
+
+
+#define __rtld_notify(word) \
+ lll_futex_wake (&(word), 1)
+
+#endif
--- libc/sysdeps/generic/ldsodefs.h 24 Aug 2006 20:27:05 -0000 1.129
+++ libc/sysdeps/generic/ldsodefs.h 10 Oct 2006 00:27:22 -0000 1.130
@@ -38,6 +38,7 @@
#include <bits/libc-lock.h>
#include <hp-timing.h>
#include <tls.h>
+#include <rtld-lowlevel.h>
__BEGIN_DECLS
--- libc/sysdeps/generic/rtld-lowlevel.h 1 Jan 1970 00:00:00 -0000
+++ libc/sysdeps/generic/rtld-lowlevel.h 10 Oct 2006 00:20:42 -0000 1.1
@@ -0,0 +1 @@
+#error "Lowlevel primitives for ld.so not implemented"