diff options
| -rw-r--r-- | ChangeLog | 32 | ||||
| -rw-r--r-- | elf/dl-close.c | 39 | ||||
| -rw-r--r-- | elf/dl-lookup.c | 31 | ||||
| -rw-r--r-- | elf/dl-object.c | 7 | ||||
| -rw-r--r-- | elf/dl-open.c | 45 | ||||
| -rw-r--r-- | elf/dl-runtime.c | 26 | ||||
| -rw-r--r-- | elf/dl-support.c | 2 | ||||
| -rw-r--r-- | elf/dl-sym.c | 10 | ||||
| -rw-r--r-- | include/link.h | 3 | ||||
| -rw-r--r-- | nptl/ChangeLog | 5 | ||||
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/rtld-lowlevel.h | 109 | ||||
| -rw-r--r-- | sysdeps/generic/ldsodefs.h | 16 |
12 files changed, 132 insertions, 193 deletions
@@ -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; |