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2208066603
Remove generic tlsdesc code related to lazy tlsdesc processing since lazy tlsdesc relocation is no longer supported. This includes removing GL(dl_load_lock) from _dl_make_tlsdesc_dynamic which is only called at load time when that lock is already held. Added a documentation comment too. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
125 lines
3.5 KiB
C
125 lines
3.5 KiB
C
/* Hash table for TLS descriptors.
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Copyright (C) 2005-2021 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Alexandre Oliva <aoliva@redhat.com>
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#ifndef TLSDESCHTAB_H
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# define TLSDESCHTAB_H 1
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#include <atomic.h>
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# ifdef SHARED
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# include <inline-hashtab.h>
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inline static int
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hash_tlsdesc (void *p)
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{
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struct tlsdesc_dynamic_arg *td = p;
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/* We know all entries are for the same module, so ti_offset is the
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only distinguishing entry. */
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return td->tlsinfo.ti_offset;
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}
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inline static int
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eq_tlsdesc (void *p, void *q)
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{
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struct tlsdesc_dynamic_arg *tdp = p, *tdq = q;
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return tdp->tlsinfo.ti_offset == tdq->tlsinfo.ti_offset;
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}
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inline static size_t
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map_generation (struct link_map *map)
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{
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size_t idx = map->l_tls_modid;
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struct dtv_slotinfo_list *listp = GL(dl_tls_dtv_slotinfo_list);
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/* Find the place in the dtv slotinfo list. */
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do
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{
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/* Does it fit in the array of this list element? */
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if (idx < listp->len)
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{
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/* We should never get here for a module in static TLS, so
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we can assume that, if the generation count is zero, we
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still haven't determined the generation count for this
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module. */
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if (listp->slotinfo[idx].map == map && listp->slotinfo[idx].gen)
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return listp->slotinfo[idx].gen;
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else
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break;
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}
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idx -= listp->len;
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listp = listp->next;
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}
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while (listp != NULL);
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/* If we get to this point, the module still hasn't been assigned an
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entry in the dtv slotinfo data structures, and it will when we're
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done with relocations. At that point, the module will get a
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generation number that is one past the current generation, so
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return exactly that. */
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return GL(dl_tls_generation) + 1;
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}
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/* Returns the data pointer for a given map and tls offset that is used
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to fill in one of the GOT entries referenced by a TLSDESC relocation
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when using dynamic TLS. This requires allocation, returns NULL on
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allocation failure. */
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void *
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_dl_make_tlsdesc_dynamic (struct link_map *map, size_t ti_offset)
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{
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struct hashtab *ht;
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void **entry;
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struct tlsdesc_dynamic_arg *td, test;
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ht = map->l_mach.tlsdesc_table;
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if (! ht)
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{
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ht = htab_create ();
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if (! ht)
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return 0;
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map->l_mach.tlsdesc_table = ht;
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}
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test.tlsinfo.ti_module = map->l_tls_modid;
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test.tlsinfo.ti_offset = ti_offset;
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entry = htab_find_slot (ht, &test, 1, hash_tlsdesc, eq_tlsdesc);
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if (! entry)
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return 0;
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if (*entry)
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{
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td = *entry;
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return td;
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}
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*entry = td = malloc (sizeof (struct tlsdesc_dynamic_arg));
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/* This may be higher than the map's generation, but it doesn't
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matter much. Worst case, we'll have one extra DTV update per
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thread. */
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td->gen_count = map_generation (map);
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td->tlsinfo = test.tlsinfo;
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return td;
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}
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# endif /* SHARED */
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#endif
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