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-rw-r--r--ChangeLog32
-rw-r--r--elf/dl-close.c39
-rw-r--r--elf/dl-lookup.c31
-rw-r--r--elf/dl-object.c7
-rw-r--r--elf/dl-open.c45
-rw-r--r--elf/dl-runtime.c26
-rw-r--r--elf/dl-support.c2
-rw-r--r--elf/dl-sym.c10
-rw-r--r--include/link.h3
-rw-r--r--nptl/ChangeLog5
-rw-r--r--nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h109
-rw-r--r--sysdeps/generic/ldsodefs.h16
12 files changed, 132 insertions, 193 deletions
diff --git a/ChangeLog b/ChangeLog
index 444973335f..5de43cb370 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,37 @@
2007-06-19 Ulrich Drepper <drepper@redhat.com>
+ * elf/dl-close.c (free_mem): Free _dl_scope_free_list.
+
+2007-06-13 Jakub Jelinek <jakub@redhat.com>
+
+ * include/link.h: Don't include rtld-lowlevel.h.
+ (struct link_map): Remove l_scope_lock.
+ * sysdeps/generic/ldsodefs.h: Don't include rtld-lowlevel.h.
+ (_dl_scope_free_list): New field (variable) in _rtld_global.
+ (DL_LOOKUP_SCOPE_LOCK): Remove.
+ (_dl_scope_free): New prototype.
+ * elf/dl-runtime.c (_dl_fixup): Don't use __rtld_mrlock_*lock.
+ Don't pass DL_LOOKUP_SCOPE_LOCK to _dl_lookup_symbol_x.
+ (_dl_profile_fixup): Likewise.
+ * elf/dl-sym.c (do_sym): Likewise. Use wrapped _dl_lookup_symbol_x
+ whenever !RTLD_SINGLE_THREAD_P, use THREAD_GSCOPE_SET_FLAG and
+ THREAD_GSCOPE_RESET_FLAG around it.
+ * elf/dl-close.c (_dl_close_worker): Don't use
+ __rtld_mrlock_{change,done}. Call _dl_scope_free on the old
+ scope. Make sure THREAD_GSCOPE_WAIT () happens if any old
+ scopes were queued or if l_scope_mem has been abandoned.
+ * elf/dl-open.c (_dl_scope_free): New function.
+ (dl_open_worker): Use it. Don't use __rtld_mrlock_{change,done}.
+ * elf/dl-support.c (_dl_scope_free_list): New variable.
+ * elf/dl-lookup.c (add_dependency): Remove flags argument.
+ Remove DL_LOOKUP_SCOPE_LOCK handling.
+ (_dl_lookup_symbol_x): Adjust caller. Remove DL_LOOKUP_SCOPE_LOCK
+ handling.
+ * elf/dl-object.c (_dl_new_object): Don't use
+ __rtld_mrlock_initialize.
+
+2007-06-19 Ulrich Drepper <drepper@redhat.com>
+
* sysdeps/generic/ldsodefs.h (rtld_global): Reorder some elements
to fill in holes
(rtld_global_ro): Likewise.
diff --git a/elf/dl-close.c b/elf/dl-close.c
index 2c2b3b6163..67188bb6c1 100644
--- a/elf/dl-close.c
+++ b/elf/dl-close.c
@@ -229,6 +229,7 @@ _dl_close_worker (struct link_map *map)
bool do_audit = GLRO(dl_naudit) > 0 && !ns->_ns_loaded->l_auditing;
#endif
bool unload_any = false;
+ bool scope_mem_left = false;
unsigned int unload_global = 0;
unsigned int first_loaded = ~0;
for (unsigned int i = 0; i < nloaded; ++i)
@@ -405,18 +406,18 @@ _dl_close_worker (struct link_map *map)
struct r_scope_elem **old = imap->l_scope;
- if (RTLD_SINGLE_THREAD_P)
- imap->l_scope = newp;
- else
- {
- __rtld_mrlock_change (imap->l_scope_lock);
- imap->l_scope = newp;
- __rtld_mrlock_done (imap->l_scope_lock);
- }
+ imap->l_scope = newp;
/* No user anymore, we can free it now. */
if (old != imap->l_scope_mem)
- free (old);
+ {
+ if (_dl_scope_free (old))
+ /* If _dl_scope_free used THREAD_GSCOPE_WAIT (),
+ no need to repeat it. */
+ scope_mem_left = false;
+ }
+ else
+ scope_mem_left = true;
imap->l_scope_max = new_size;
}
@@ -485,9 +486,21 @@ _dl_close_worker (struct link_map *map)
j++;
}
ns_msl->r_nlist = j;
+ }
- if (!RTLD_SINGLE_THREAD_P)
- THREAD_GSCOPE_WAIT ();
+ if (!RTLD_SINGLE_THREAD_P
+ && (unload_global
+ || scope_mem_left
+ || (GL(dl_scope_free_list) != NULL
+ && GL(dl_scope_free_list)->count)))
+ {
+ THREAD_GSCOPE_WAIT ();
+
+ /* Now we can free any queued old scopes. */
+ struct dl_scope_free_list *fsl = GL(dl_scope_free_list);
+ if (fsl != NULL)
+ while (fsl->count > 0)
+ free (fsl->list[--fsl->count]);
}
size_t tls_free_start;
@@ -786,4 +799,8 @@ libc_freeres_fn (free_mem)
malloc), and in the static library it's in .bss space. */
free_slotinfo (&GL(dl_tls_dtv_slotinfo_list)->next);
}
+
+ void *scope_free_list = GL(dl_scope_free_list);
+ GL(dl_scope_free_list) = NULL;
+ free (scope_free_list);
}
diff --git a/elf/dl-lookup.c b/elf/dl-lookup.c
index dc1b865bc7..f4e5ce805f 100644
--- a/elf/dl-lookup.c
+++ b/elf/dl-lookup.c
@@ -86,7 +86,7 @@ dl_new_hash (const char *s)
/* Add extra dependency on MAP to UNDEF_MAP. */
static int
internal_function
-add_dependency (struct link_map *undef_map, struct link_map *map, int flags)
+add_dependency (struct link_map *undef_map, struct link_map *map)
{
struct link_map **list;
struct link_map *runp;
@@ -99,18 +99,8 @@ add_dependency (struct link_map *undef_map, struct link_map *map, int flags)
if (undef_map == map)
return 0;
- /* Make sure nobody can unload the object while we are at it.
- If we hold a scope lock drop it now to avoid ABBA locking problems. */
- if ((flags & DL_LOOKUP_SCOPE_LOCK) != 0 && !RTLD_SINGLE_THREAD_P)
- {
- __rtld_mrlock_unlock (undef_map->l_scope_lock);
-
- __rtld_lock_lock_recursive (GL(dl_load_lock));
-
- __rtld_mrlock_lock (undef_map->l_scope_lock);
- }
- else
- __rtld_lock_lock_recursive (GL(dl_load_lock));
+ /* Make sure nobody can unload the object while we are at it. */
+ __rtld_lock_lock_recursive (GL(dl_load_lock));
/* Avoid references to objects which cannot be unloaded anyway. */
if (map->l_type != lt_loaded
@@ -237,10 +227,9 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
bump_num_relocations ();
- /* No other flag than DL_LOOKUP_ADD_DEPENDENCY and DL_LOOKUP_SCOPE_LOCK
- is allowed if we look up a versioned symbol. */
- assert (version == NULL || (flags & ~(DL_LOOKUP_ADD_DEPENDENCY
- | DL_LOOKUP_SCOPE_LOCK)) == 0);
+ /* No other flag than DL_LOOKUP_ADD_DEPENDENCY is allowed if we look
+ up a versioned symbol. */
+ assert (version == NULL || (flags & ~(DL_LOOKUP_ADD_DEPENDENCY)) == 0);
size_t i = 0;
if (__builtin_expect (skip_map != NULL, 0))
@@ -346,13 +335,11 @@ _dl_lookup_symbol_x (const char *undef_name, struct link_map *undef_map,
runtime lookups. */
&& (flags & DL_LOOKUP_ADD_DEPENDENCY) != 0
/* Add UNDEF_MAP to the dependencies. */
- && add_dependency (undef_map, current_value.m, flags) < 0)
+ && add_dependency (undef_map, current_value.m) < 0)
/* Something went wrong. Perhaps the object we tried to reference
was just removed. Try finding another definition. */
- return _dl_lookup_symbol_x (undef_name, undef_map, ref,
- (flags & DL_LOOKUP_SCOPE_LOCK) == 0
- ? symbol_scope : undef_map->l_scope, version,
- type_class, flags, skip_map);
+ return _dl_lookup_symbol_x (undef_name, undef_map, ref, symbol_scope,
+ version, type_class, flags, skip_map);
/* The object is used. */
current_value.m->l_used = 1;
diff --git a/elf/dl-object.c b/elf/dl-object.c
index 33ee860e59..22ae832393 100644
--- a/elf/dl-object.c
+++ b/elf/dl-object.c
@@ -1,5 +1,5 @@
/* Storage management for the chain of loaded shared objects.
- Copyright (C) 1995-2002, 2004, 2006 Free Software Foundation, Inc.
+ Copyright (C) 1995-2002, 2004, 2006, 2007 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
@@ -85,11 +85,6 @@ _dl_new_object (char *realname, const char *libname, int type,
new->l_scope = new->l_scope_mem;
new->l_scope_max = sizeof (new->l_scope_mem) / sizeof (new->l_scope_mem[0]);
- /* No need to initialize the scope lock if the initializer is zero. */
-#if _RTLD_MRLOCK_INITIALIZER != 0
- __rtld_mrlock_initialize (new->l_scope_lock);
-#endif
-
/* Counter for the scopes we have to handle. */
idx = 0;
diff --git a/elf/dl-open.c b/elf/dl-open.c
index 2000f580c3..fda3219ae2 100644
--- a/elf/dl-open.c
+++ b/elf/dl-open.c
@@ -165,6 +165,40 @@ add_to_global (struct link_map *new)
return 0;
}
+int
+_dl_scope_free (struct r_scope_elem **old)
+{
+ struct dl_scope_free_list *fsl;
+#define DL_SCOPE_FREE_LIST_SIZE (sizeof (fsl->list) / sizeof (fsl->list[0]))
+
+ if (RTLD_SINGLE_THREAD_P)
+ free (old);
+ else if ((fsl = GL(dl_scope_free_list)) == NULL)
+ {
+ GL(dl_scope_free_list) = fsl = malloc (sizeof (*fsl));
+ if (fsl == NULL)
+ {
+ THREAD_GSCOPE_WAIT ();
+ free (old);
+ return 1;
+ }
+ else
+ {
+ fsl->list[0] = old;
+ fsl->count = 1;
+ }
+ }
+ else if (fsl->count < DL_SCOPE_FREE_LIST_SIZE)
+ fsl->list[fsl->count++] = old;
+ else
+ {
+ THREAD_GSCOPE_WAIT ();
+ while (fsl->count > 0)
+ free (fsl->list[--fsl->count]);
+ return 1;
+ }
+ return 0;
+}
static void
dl_open_worker (void *a)
@@ -429,17 +463,10 @@ dl_open_worker (void *a)
memcpy (newp, imap->l_scope, cnt * sizeof (imap->l_scope[0]));
struct r_scope_elem **old = imap->l_scope;
- if (RTLD_SINGLE_THREAD_P)
- imap->l_scope = newp;
- else
- {
- __rtld_mrlock_change (imap->l_scope_lock);
- imap->l_scope = newp;
- __rtld_mrlock_done (imap->l_scope_lock);
- }
+ imap->l_scope = newp;
if (old != imap->l_scope_mem)
- free (old);
+ _dl_scope_free (old);
imap->l_scope_max = new_size;
}
diff --git a/elf/dl-runtime.c b/elf/dl-runtime.c
index 6add5e4fff..ee2b8b5f6c 100644
--- a/elf/dl-runtime.c
+++ b/elf/dl-runtime.c
@@ -100,22 +100,11 @@ _dl_fixup (
we are not using any threads (yet). */
int flags = DL_LOOKUP_ADD_DEPENDENCY;
if (!RTLD_SINGLE_THREAD_P)
- {
- THREAD_GSCOPE_SET_FLAG ();
-
- if (l->l_type == lt_loaded)
- {
- __rtld_mrlock_lock (l->l_scope_lock);
- flags |= DL_LOOKUP_SCOPE_LOCK;
- }
- }
+ THREAD_GSCOPE_SET_FLAG ();
result = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym, l->l_scope,
version, ELF_RTYPE_CLASS_PLT, flags, NULL);
- if ((flags & DL_LOOKUP_SCOPE_LOCK) != 0)
- __rtld_mrlock_unlock (l->l_scope_lock);
-
/* We are done with the global scope. */
if (!RTLD_SINGLE_THREAD_P)
THREAD_GSCOPE_RESET_FLAG ();
@@ -203,23 +192,12 @@ _dl_profile_fixup (
we are not using any threads (yet). */
int flags = DL_LOOKUP_ADD_DEPENDENCY;
if (!RTLD_SINGLE_THREAD_P)
- {
- THREAD_GSCOPE_SET_FLAG ();
-
- if (l->l_type == lt_loaded)
- {
- __rtld_mrlock_lock (l->l_scope_lock);
- flags |= DL_LOOKUP_SCOPE_LOCK;
- }
- }
+ THREAD_GSCOPE_SET_FLAG ();
result = _dl_lookup_symbol_x (strtab + refsym->st_name, l,
&defsym, l->l_scope, version,
ELF_RTYPE_CLASS_PLT, flags, NULL);
- if ((flags & DL_LOOKUP_SCOPE_LOCK) != 0)
- __rtld_mrlock_unlock (l->l_scope_lock);
-
/* We are done with the global scope. */
if (!RTLD_SINGLE_THREAD_P)
THREAD_GSCOPE_RESET_FLAG ();
diff --git a/elf/dl-support.c b/elf/dl-support.c
index cecb603ae6..2c11ac6881 100644
--- a/elf/dl-support.c
+++ b/elf/dl-support.c
@@ -135,6 +135,8 @@ int (*_dl_make_stack_executable_hook) (void **) internal_function
/* Function in libpthread to wait for termination of lookups. */
void (*_dl_wait_lookup_done) (void);
+struct dl_scope_free_list *_dl_scope_free_list;
+
#ifdef NEED_DL_SYSINFO
/* Needed for improved syscall handling on at least x86/Linux. */
uintptr_t _dl_sysinfo = DL_SYSINFO_DEFAULT;
diff --git a/elf/dl-sym.c b/elf/dl-sym.c
index 0e1b258b5a..b12ff375fe 100644
--- a/elf/dl-sym.c
+++ b/elf/dl-sym.c
@@ -112,29 +112,29 @@ do_sym (void *handle, const char *name, void *who,
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 || RTLD_SINGLE_THREAD_P)
+ if (RTLD_SINGLE_THREAD_P)
result = GLRO(dl_lookup_symbol_x) (name, match, &ref,
match->l_scope, vers, 0,
flags | DL_LOOKUP_ADD_DEPENDENCY,
NULL);
else
{
- __rtld_mrlock_lock (match->l_scope_lock);
-
struct call_dl_lookup_args args;
args.name = name;
args.map = match;
args.vers = vers;
- args.flags = flags | DL_LOOKUP_ADD_DEPENDENCY | DL_LOOKUP_SCOPE_LOCK;
+ args.flags = flags | DL_LOOKUP_ADD_DEPENDENCY;
args.refp = &ref;
+ THREAD_GSCOPE_SET_FLAG ();
+
const char *objname;
const char *errstring = NULL;
bool malloced;
int err = GLRO(dl_catch_error) (&objname, &errstring, &malloced,
call_dl_lookup, &args);
- __rtld_mrlock_unlock (match->l_scope_lock);
+ THREAD_GSCOPE_RESET_FLAG ();
if (__builtin_expect (errstring != NULL, 0))
{
diff --git a/include/link.h b/include/link.h
index 56764a9164..ccbbb8c45e 100644
--- a/include/link.h
+++ b/include/link.h
@@ -44,7 +44,6 @@ extern unsigned int la_objopen (struct link_map *__map, Lmid_t __lmid,
#include <dl-lookupcfg.h>
#include <tls.h>
#include <bits/libc-lock.h>
-#include <rtld-lowlevel.h>
/* Some internal data structures of the dynamic linker used in the
@@ -223,8 +222,6 @@ struct link_map
/* 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;
- /* We need to protect using the SCOPEREC. */
- __rtld_mrlock_define (, l_scope_lock)
/* A similar array, this time only with the local scope. This is
used occasionally. */
diff --git a/nptl/ChangeLog b/nptl/ChangeLog
index 87028ca704..12ba85c558 100644
--- a/nptl/ChangeLog
+++ b/nptl/ChangeLog
@@ -1,3 +1,8 @@
+2007-06-19 Ulrich Drepper <drepper@redhat.com>
+
+ * sysdeps/unix/sysv/linux/rtld-lowlevel.h: Remove mrlock
+ implementation.
+
2007-06-18 Ulrich Drepper <drepper@redhat.com>
* pthreadP.h: Define PTHREAD_MUTEX_TYPE.
diff --git a/nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h b/nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h
index e805b63001..1aeff8fb39 100644
--- a/nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h
+++ b/nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h
@@ -24,115 +24,6 @@
#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; \
- oldval = ret; \
- } \
- atomic_delay (); \
- } \
- if ((oldval & __RTLD_MRLOCK_RWAIT) == 0) \
- { \
- atomic_or (&(lock), __RTLD_MRLOCK_RWAIT); \
- oldval |= __RTLD_MRLOCK_RWAIT; \
- } \
- lll_private_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_private_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; \
- oldval = ret; \
- } \
- atomic_delay (); \
- } \
- atomic_or (&(lock), __RTLD_MRLOCK_WWAIT); \
- oldval |= __RTLD_MRLOCK_WWAIT; \
- lll_private_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_private_futex_wake (&(lock), 0x7fffffff); \
- } while (0)
-
-
/* Function to wait for variable become zero. Used in ld.so for
reference counters. */
#define __rtld_waitzero(word) \
diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h
index c910ed59c4..aefd105f0a 100644
--- a/sysdeps/generic/ldsodefs.h
+++ b/sysdeps/generic/ldsodefs.h
@@ -38,7 +38,6 @@
#include <bits/libc-lock.h>
#include <hp-timing.h>
#include <tls.h>
-#include <rtld-lowlevel.h>
__BEGIN_DECLS
@@ -488,6 +487,12 @@ struct rtld_global
EXTERN void (*_dl_wait_lookup_done) (void);
+ /* Scopes to free after next THREAD_GSCOPE_WAIT (). */
+ EXTERN struct dl_scope_free_list
+ {
+ size_t count;
+ struct r_scope_elem **list[50];
+ } *_dl_scope_free_list;
#ifdef SHARED
};
# define __rtld_global_attribute__
@@ -840,9 +845,7 @@ enum
DL_LOOKUP_ADD_DEPENDENCY = 1,
/* Return most recent version instead of default version for
unversioned lookup. */
- DL_LOOKUP_RETURN_NEWEST = 2,
- /* Set if the scopr lock in the UNDEF_MAP is taken. */
- DL_LOOKUP_SCOPE_LOCK = 4
+ DL_LOOKUP_RETURN_NEWEST = 2
};
/* Lookup versioned symbol. */
@@ -1050,6 +1053,11 @@ extern void *_dl_open (const char *name, int mode, const void *caller,
Lmid_t nsid, int argc, char *argv[], char *env[])
attribute_hidden;
+/* Free or queue for freeing scope OLD. If other threads might be
+ in the middle of _dl_fixup, _dl_profile_fixup or dl*sym using the
+ old scope, OLD can't be freed until no thread is using it. */
+extern int _dl_scope_free (struct r_scope_elem **old) attribute_hidden;
+
/* Add module to slot information data. */
extern void _dl_add_to_slotinfo (struct link_map *l) attribute_hidden;