diff options
Diffstat (limited to 'elf/dl-close.c')
| -rw-r--r-- | elf/dl-close.c | 113 |
1 files changed, 41 insertions, 72 deletions
diff --git a/elf/dl-close.c b/elf/dl-close.c index ea62d0e601..b887a44888 100644 --- a/elf/dl-close.c +++ b/elf/dl-close.c @@ -138,31 +138,30 @@ _dl_close_worker (struct link_map *map, bool force) bool any_tls = false; const unsigned int nloaded = ns->_ns_nloaded; + struct link_map *maps[nloaded]; - /* Run over the list and assign indexes to the link maps. */ + /* Run over the list and assign indexes to the link maps and enter + them into the MAPS array. */ int idx = 0; for (struct link_map *l = ns->_ns_loaded; l != NULL; l = l->l_next) { l->l_map_used = 0; l->l_map_done = 0; l->l_idx = idx; + maps[idx] = l; ++idx; } assert (idx == nloaded); - /* Keep marking link maps until no new link maps are found. */ - for (struct link_map *l = ns->_ns_loaded; l != NULL; ) + /* Keep track of the lowest index link map we have covered already. */ + int done_index = -1; + while (++done_index < nloaded) { - /* next is reset to earlier link maps for remarking. */ - struct link_map *next = l->l_next; - int next_idx = l->l_idx + 1; /* next->l_idx, but covers next == NULL. */ + struct link_map *l = maps[done_index]; if (l->l_map_done) - { - /* Already handled. */ - l = next; - continue; - } + /* Already handled. */ + continue; /* Check whether this object is still used. */ if (l->l_type == lt_loaded @@ -172,10 +171,7 @@ _dl_close_worker (struct link_map *map, bool force) acquire is sufficient and correct. */ && atomic_load_acquire (&l->l_tls_dtor_count) == 0 && !l->l_map_used) - { - l = next; - continue; - } + continue; /* We need this object and we handle it now. */ l->l_map_used = 1; @@ -202,11 +198,8 @@ _dl_close_worker (struct link_map *map, bool force) already processed it, then we need to go back and process again from that point forward to ensure we keep all of its dependencies also. */ - if ((*lp)->l_idx < next_idx) - { - next = *lp; - next_idx = next->l_idx; - } + if ((*lp)->l_idx - 1 < done_index) + done_index = (*lp)->l_idx - 1; } } @@ -226,65 +219,44 @@ _dl_close_worker (struct link_map *map, bool force) if (!jmap->l_map_used) { jmap->l_map_used = 1; - if (jmap->l_idx < next_idx) - { - next = jmap; - next_idx = next->l_idx; - } + if (jmap->l_idx - 1 < done_index) + done_index = jmap->l_idx - 1; } } } - - l = next; } - /* Call the destructors in reverse constructor order, and remove the - closed link maps from the list. */ - for (struct link_map **init_called_head = &_dl_init_called_list; - *init_called_head != NULL; ) + /* Sort the entries. We can skip looking for the binary itself which is + at the front of the search list for the main namespace. */ + _dl_sort_maps (maps, nloaded, (nsid == LM_ID_BASE), true); + + /* Call all termination functions at once. */ + 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) { - struct link_map *imap = *init_called_head; + struct link_map *imap = maps[i]; - /* _dl_init_called_list is global, to produce a global odering. - Ignore the other namespaces (and link maps that are still used). */ - if (imap->l_ns != nsid || imap->l_map_used) - init_called_head = &imap->l_init_called_next; - else + /* All elements must be in the same namespace. */ + assert (imap->l_ns == nsid); + + if (!imap->l_map_used) { assert (imap->l_type == lt_loaded && !imap->l_nodelete_active); - /* _dl_init_called_list is updated at the same time as - l_init_called. */ - assert (imap->l_init_called); - - if (imap->l_info[DT_FINI_ARRAY] != NULL - || imap->l_info[DT_FINI] != NULL) + /* Call its termination function. Do not do it for + half-cooked objects. Temporarily disable exception + handling, so that errors are fatal. */ + if (imap->l_init_called) _dl_catch_exception (NULL, _dl_call_fini, imap); #ifdef SHARED /* Auditing checkpoint: we remove an object. */ _dl_audit_objclose (imap); #endif - /* Unlink this link map. */ - *init_called_head = imap->l_init_called_next; - } - } - - - bool unload_any = false; - bool scope_mem_left = false; - unsigned int unload_global = 0; - - /* For skipping un-unloadable link maps in the second loop. */ - struct link_map *first_loaded = ns->_ns_loaded; - /* Iterate over the namespace to find objects to unload. Some - unloadable objects may not be on _dl_init_called_list due to - dlopen failure. */ - for (struct link_map *imap = first_loaded; imap != NULL; imap = imap->l_next) - { - if (!imap->l_map_used) - { /* This object must not be used anymore. */ imap->l_removed = 1; @@ -295,8 +267,8 @@ _dl_close_worker (struct link_map *map, bool force) ++unload_global; /* Remember where the first dynamically loaded object is. */ - if (first_loaded == NULL) - first_loaded = imap; + if (i < first_loaded) + first_loaded = i; } /* Else imap->l_map_used. */ else if (imap->l_type == lt_loaded) @@ -432,8 +404,8 @@ _dl_close_worker (struct link_map *map, bool force) imap->l_loader = NULL; /* Remember where the first dynamically loaded object is. */ - if (first_loaded == NULL) - first_loaded = imap; + if (i < first_loaded) + first_loaded = i; } } @@ -504,11 +476,10 @@ _dl_close_worker (struct link_map *map, bool force) /* Check each element of the search list to see if all references to it are gone. */ - for (struct link_map *imap = first_loaded; imap != NULL; ) + for (unsigned int i = first_loaded; i < nloaded; ++i) { - if (imap->l_map_used) - imap = imap->l_next; - else + struct link_map *imap = maps[i]; + if (!imap->l_map_used) { assert (imap->l_type == lt_loaded); @@ -719,9 +690,7 @@ _dl_close_worker (struct link_map *map, bool force) if (imap == GL(dl_initfirst)) GL(dl_initfirst) = NULL; - struct link_map *next = imap->l_next; free (imap); - imap = next; } } |