From patchwork Wed May 12 16:58:10 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 43406 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 6A563399C02B; Wed, 12 May 2021 16:58:18 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 6A563399C02B DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1620838698; bh=KiNBsYBSG7kjRrJiJ0LVZT5KxAcJsWsVKxDdQWL9o48=; h=To:Subject:In-Reply-To:References:Date:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=aQPJGJunM7+ne+vXohsffxDqNUkGIgbvhur6nS18leDSJOOnCw4ZEIgFa9gSp1SSh VsEuJQbU1Zsc+0LGIRcJ6JlqMRn7If5G/vSQBlMMm+vpOz7fJonb9YalpX9fW8tSDQ WMCBMT17711MZ/MkUd81nx7xo3/UTR1hJEixLHAo= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by sourceware.org (Postfix) with ESMTP id 2AF013990834 for ; Wed, 12 May 2021 16:58:16 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 2AF013990834 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-560-SUJTMyLyM4GNMih9cU1mYQ-1; Wed, 12 May 2021 12:58:14 -0400 X-MC-Unique: SUJTMyLyM4GNMih9cU1mYQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id B228B8018A1 for ; Wed, 12 May 2021 16:58:13 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-112-137.ams2.redhat.com [10.36.112.137]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D94C21B058 for ; Wed, 12 May 2021 16:58:12 +0000 (UTC) To: libc-alpha@sourceware.org Subject: [PATCH 11/23] elf: Move static TLS size and alignment into _rtld_global_ro In-Reply-To: References: X-From-Line: 310d3f42a889e5fd9651cd1be3917f490666630c Mon Sep 17 00:00:00 2001 Message-Id: <310d3f42a889e5fd9651cd1be3917f490666630c.1620838411.git.fweimer@redhat.com> Date: Wed, 12 May 2021 18:58:10 +0200 User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-12.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Florian Weimer via Libc-alpha From: Florian Weimer Reply-To: Florian Weimer Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" This helps to clarify that the caching of these fields in libpthread (in __static_tls_size, __static_tls_align_m1) is unnecessary. Reviewed-by: Adhemerval Zanella --- elf/dl-reloc.c | 6 +++--- elf/dl-tls.c | 22 +++++++++++----------- elf/rtld_static_init.c | 6 ++++++ sysdeps/generic/ldsodefs.h | 10 ++++++---- 4 files changed, 26 insertions(+), 18 deletions(-) diff --git a/elf/dl-reloc.c b/elf/dl-reloc.c index bb9ca1a101..e13a672ade 100644 --- a/elf/dl-reloc.c +++ b/elf/dl-reloc.c @@ -53,14 +53,14 @@ _dl_try_allocate_static_tls (struct link_map *map, bool optional) /* If we've already used the variable with dynamic access, or if the alignment requirements are too high, fail. */ if (map->l_tls_offset == FORCED_DYNAMIC_TLS_OFFSET - || map->l_tls_align > GL(dl_tls_static_align)) + || map->l_tls_align > GLRO (dl_tls_static_align)) { fail: return -1; } #if TLS_TCB_AT_TP - size_t freebytes = GL(dl_tls_static_size) - GL(dl_tls_static_used); + size_t freebytes = GLRO (dl_tls_static_size) - GL(dl_tls_static_used); if (freebytes < TLS_TCB_SIZE) goto fail; freebytes -= TLS_TCB_SIZE; @@ -89,7 +89,7 @@ _dl_try_allocate_static_tls (struct link_map *map, bool optional) + map->l_tls_firstbyte_offset); size_t used = offset + map->l_tls_blocksize; - if (used > GL(dl_tls_static_size)) + if (used > GLRO (dl_tls_static_size)) goto fail; /* Account optional static TLS surplus usage. */ diff --git a/elf/dl-tls.c b/elf/dl-tls.c index 67781bc108..91031c2b72 100644 --- a/elf/dl-tls.c +++ b/elf/dl-tls.c @@ -300,9 +300,9 @@ _dl_determine_tlsoffset (void) } GL(dl_tls_static_used) = offset; - GL(dl_tls_static_size) = (roundup (offset + GLRO(dl_tls_static_surplus), - max_align) - + TLS_TCB_SIZE); + GLRO (dl_tls_static_size) = (roundup (offset + GLRO(dl_tls_static_surplus), + max_align) + + TLS_TCB_SIZE); #elif TLS_DTV_AT_TP /* The TLS blocks start right after the TCB. */ size_t offset = TLS_TCB_SIZE; @@ -345,14 +345,14 @@ _dl_determine_tlsoffset (void) } GL(dl_tls_static_used) = offset; - GL(dl_tls_static_size) = roundup (offset + GLRO(dl_tls_static_surplus), - TLS_TCB_ALIGN); + GLRO (dl_tls_static_size) = roundup (offset + GLRO(dl_tls_static_surplus), + TLS_TCB_ALIGN); #else # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined" #endif /* The alignment requirement for the static TLS block. */ - GL(dl_tls_static_align) = max_align; + GLRO (dl_tls_static_align) = max_align; } #endif /* SHARED */ @@ -391,8 +391,8 @@ allocate_dtv (void *result) void _dl_get_tls_static_info (size_t *sizep, size_t *alignp) { - *sizep = GL(dl_tls_static_size); - *alignp = GL(dl_tls_static_align); + *sizep = GLRO (dl_tls_static_size); + *alignp = GLRO (dl_tls_static_align); } /* Derive the location of the pointer to the start of the original @@ -416,7 +416,7 @@ void * _dl_allocate_tls_storage (void) { void *result; - size_t size = GL(dl_tls_static_size); + size_t size = GLRO (dl_tls_static_size); #if TLS_DTV_AT_TP /* Memory layout is: @@ -427,7 +427,7 @@ _dl_allocate_tls_storage (void) /* Perform the allocation. Reserve space for the required alignment and the pointer to the original allocation. */ - size_t alignment = GL(dl_tls_static_align); + size_t alignment = GLRO (dl_tls_static_align); void *allocated = malloc (size + alignment + sizeof (void *)); if (__glibc_unlikely (allocated == NULL)) return NULL; @@ -436,7 +436,7 @@ _dl_allocate_tls_storage (void) #if TLS_TCB_AT_TP /* The TCB follows the TLS blocks, which determine the alignment. (TCB alignment requirements have been taken into account when - calculating GL(dl_tls_static_align).) */ + calculating GLRO (dl_tls_static_align).) */ void *aligned = (void *) roundup ((uintptr_t) allocated, alignment); result = aligned + size - TLS_TCB_SIZE; diff --git a/elf/rtld_static_init.c b/elf/rtld_static_init.c index cd823096d6..bded6bd2d4 100644 --- a/elf/rtld_static_init.c +++ b/elf/rtld_static_init.c @@ -51,6 +51,12 @@ __rtld_static_init (struct link_map *map) dl->_dl_hwcap2 = _dl_hwcap2; extern __typeof (dl->_dl_pagesize) _dl_pagesize attribute_hidden; dl->_dl_pagesize = _dl_pagesize; + extern __typeof (dl->_dl_tls_static_align) _dl_tls_static_align + attribute_hidden; + dl->_dl_tls_static_align = _dl_tls_static_align; + extern __typeof (dl->_dl_tls_static_size) _dl_tls_static_size + attribute_hidden; + dl->_dl_tls_static_size = _dl_tls_static_size; __rtld_static_init_arch (map, dl); } diff --git a/sysdeps/generic/ldsodefs.h b/sysdeps/generic/ldsodefs.h index c288f3a2a1..e383aa1dc3 100644 --- a/sysdeps/generic/ldsodefs.h +++ b/sysdeps/generic/ldsodefs.h @@ -437,12 +437,8 @@ struct rtld_global } *_dl_tls_dtv_slotinfo_list; /* Number of modules in the static TLS block. */ EXTERN size_t _dl_tls_static_nelem; - /* Size of the static TLS block. */ - EXTERN size_t _dl_tls_static_size; /* Size actually allocated in the static TLS block. */ EXTERN size_t _dl_tls_static_used; - /* Alignment requirement of the static TLS block. */ - EXTERN size_t _dl_tls_static_align; /* Remaining amount of static TLS that may be used for optimizing dynamic TLS access (e.g. with TLSDESC). */ EXTERN size_t _dl_tls_static_optional; @@ -610,6 +606,12 @@ struct rtld_global_ro binaries, don't honor for PIEs). */ EXTERN ElfW(Addr) _dl_use_load_bias; + /* Size of the static TLS block. */ + EXTERN size_t _dl_tls_static_size; + + /* Alignment requirement of the static TLS block. */ + EXTERN size_t _dl_tls_static_align; + /* Size of surplus space in the static TLS area for dynamically loaded modules with IE-model TLS or for TLSDESC optimization. See comments in elf/dl-tls.c where it is initialized. */