diff options
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | elf/dl-tls.c | 99 |
2 files changed, 61 insertions, 43 deletions
diff --git a/ChangeLog b/ChangeLog index fa59286292..2c21a7d571 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2008-05-11 Ulrich Drepper <drepper@redhat.com> + + * elf/dl-tls.c (__tls_get_addr): Optimize by moving slow path in + its own function. This reduces the frame setup costs and more. + 2008-02-11 Joseph Myers <joseph@codesourcery.com> [BZ #3406] diff --git a/elf/dl-tls.c b/elf/dl-tls.c index 76a3f25c0f..54c3590a9d 100644 --- a/elf/dl-tls.c +++ b/elf/dl-tls.c @@ -691,6 +691,61 @@ _dl_update_slotinfo (unsigned long int req_modid) } +static void * +__attribute_noinline__ +tls_get_addr_tail (dtv_t *dtv, struct link_map *the_map, size_t module) +{ + /* The allocation was deferred. Do it now. */ + if (the_map == NULL) + { + /* Find the link map for this module. */ + size_t idx = module; + struct dtv_slotinfo_list *listp = GL(dl_tls_dtv_slotinfo_list); + + while (idx >= listp->len) + { + idx -= listp->len; + listp = listp->next; + } + + the_map = listp->slotinfo[idx].map; + } + + again: + /* Make sure that, if a dlopen running in parallel forces the + variable into static storage, we'll wait until the address in the + static TLS block is set up, and use that. If we're undecided + yet, make sure we make the decision holding the lock as well. */ + if (__builtin_expect (the_map->l_tls_offset + != FORCED_DYNAMIC_TLS_OFFSET, 0)) + { + __rtld_lock_lock_recursive (GL(dl_load_lock)); + if (__builtin_expect (the_map->l_tls_offset == NO_TLS_OFFSET, 1)) + { + the_map->l_tls_offset = FORCED_DYNAMIC_TLS_OFFSET; + __rtld_lock_unlock_recursive (GL(dl_load_lock)); + } + else + { + __rtld_lock_unlock_recursive (GL(dl_load_lock)); + if (__builtin_expect (the_map->l_tls_offset + != FORCED_DYNAMIC_TLS_OFFSET, 1)) + { + void *p = dtv[module].pointer.val; + if (__builtin_expect (p == TLS_DTV_UNALLOCATED, 0)) + goto again; + + return p; + } + } + } + void *p = dtv[module].pointer.val = allocate_and_init (the_map); + dtv[module].pointer.is_static = false; + + return p; +} + + /* The generic dynamic and local dynamic model cannot be used in statically linked applications. */ void * @@ -703,52 +758,10 @@ __tls_get_addr (GET_ADDR_ARGS) if (__builtin_expect (dtv[0].counter != GL(dl_tls_generation), 0)) the_map = _dl_update_slotinfo (GET_ADDR_MODULE); - retry: p = dtv[GET_ADDR_MODULE].pointer.val; if (__builtin_expect (p == TLS_DTV_UNALLOCATED, 0)) - { - /* The allocation was deferred. Do it now. */ - if (the_map == NULL) - { - /* Find the link map for this module. */ - size_t idx = GET_ADDR_MODULE; - struct dtv_slotinfo_list *listp = GL(dl_tls_dtv_slotinfo_list); - - while (idx >= listp->len) - { - idx -= listp->len; - listp = listp->next; - } - - the_map = listp->slotinfo[idx].map; - } - - /* Make sure that, if a dlopen running in parallel forces the - variable into static storage, we'll wait until the address in - the static TLS block is set up, and use that. If we're - undecided yet, make sure we make the decision holding the - lock as well. */ - if (__builtin_expect (the_map->l_tls_offset - != FORCED_DYNAMIC_TLS_OFFSET, 0)) - { - __rtld_lock_lock_recursive (GL(dl_load_lock)); - if (__builtin_expect (the_map->l_tls_offset == NO_TLS_OFFSET, 1)) - { - the_map->l_tls_offset = FORCED_DYNAMIC_TLS_OFFSET; - __rtld_lock_unlock_recursive (GL(dl_load_lock)); - } - else - { - __rtld_lock_unlock_recursive (GL(dl_load_lock)); - if (__builtin_expect (the_map->l_tls_offset - != FORCED_DYNAMIC_TLS_OFFSET, 1)) - goto retry; - } - } - p = dtv[GET_ADDR_MODULE].pointer.val = allocate_and_init (the_map); - dtv[GET_ADDR_MODULE].pointer.is_static = false; - } + p = tls_get_addr_tail (dtv, the_map, GET_ADDR_MODULE); return (char *) p + GET_ADDR_OFFSET; } |