From 3fb558781fe9bdad55c25157eaea0531e727ba39 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 7 Feb 2002 04:08:19 +0000 Subject: Update. 2002-02-06 Ulrich Drepper * Versions.def [ld]: Add GLIBC_2.3. * elf/Versions [ld]: Add __tls_get_addr to GLIBC_2.3. * elf/Makefile (dl-routines): Add dl-tls. (distribute): Add dl-tls.h. * sysdeps/generic/ldsodefs.h (struct rtld_global): Remove _dl_tls_module_cnt, add _dl_tls_max_dtv_idx and _dl_tls_dtv_gaps. Add prototypes for _dl_next_tls_modid and _dl_determine_tlsoffset. * elf/dl-load.c (_dl_map_object_from_fd): Store alignment requirement along with the other info in the link map. Change queueing of init images for double linked list. Use _dl_next_tls_modid to compute l_tls_modid. * elf/rtld.c (_dl_start_final): Store alignment requirement along with the other info in rtld map and executable map. (dl_main): Add ld.so to the init image list if necessary. Compute final module ID with _dl_next_tls_modid. * include/link.h (struct link_map): Add l_tls_previmage and l_tls_align. * eld/dl-support.c: Define _dl_tls_max_dtv_idx and _dl_tls_dtv_gaps. * sysdeps/i386/elf/Versions: New file. * sysdeps/generic/dl-tls.c: New file. * sysdeps/generic/dl-tls.h: New file. * sysdeps/i386/dl-tls.h: New file. attribute((packed)) to counter stupid people misusing gcc options. --- elf/dl-support.c | 6 +++-- elf/rtld.c | 72 +++++++++++++++++++++++++++++++++++++++++++------------- 2 files changed, 60 insertions(+), 18 deletions(-) (limited to 'elf') diff --git a/elf/dl-support.c b/elf/dl-support.c index 10446dc68a..4eaa6757a2 100644 --- a/elf/dl-support.c +++ b/elf/dl-support.c @@ -143,8 +143,10 @@ __libc_lock_define_initialized_recursive (, _dl_load_lock) initialize new TLS blocks. */ struct link_map *_dl_initimage_list; -/* Count the number of modules which define TLS data. */ -size_t _dl_tls_module_cnt; +/* Highest dtv index currently needed. */ +size_t _dl_tls_max_dtv_idx; +/* Flag signalling whether there are gaps in the module ID allocation. */ +bool _dl_tls_dtv_gaps; #endif diff --git a/elf/rtld.c b/elf/rtld.c index b9cda1d841..088e761e64 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -259,9 +259,11 @@ _dl_start_final (void *arg, struct link_map *bootstrap_map_p, if (phdr[cnt].p_type == PT_TLS) { void *tlsblock; - size_t align = MAX (TLS_INIT_TCB_ALIGN, phdr[cnt].p_align); + size_t max_align = MAX (TLS_INIT_TCB_ALIGN, phdr[cnt].p_align); GL(dl_rtld_map).l_tls_blocksize = phdr[cnt].p_memsz; + GL(dl_rtld_map).l_tls_align = phdr[cnt].p_align; + assert (GL(dl_rtld_map).l_tls_blocksize != 0); GL(dl_rtld_map).l_tls_initimage_size = phdr[cnt].p_filesz; GL(dl_rtld_map).l_tls_initimage = (void *) (GL(dl_rtld_map).l_map_start + phdr[cnt].p_offset); @@ -274,19 +276,20 @@ _dl_start_final (void *arg, struct link_map *bootstrap_map_p, tlsblock = alloca (roundup (GL(dl_rtld_map).l_tls_blocksize, TLS_INIT_TCB_ALIGN) + TLS_INIT_TCB_SIZE - + align); + + max_align); # elif TLS_DTV_AT_TP - tlsblock = alloca (roundup (TLS_INIT_TCB_SIZE, phdr[cnt].p_align) + tlsblock = alloca (roundup (TLS_INIT_TCB_SIZE, + GL(dl_rtld_map).l_tls_align) + GL(dl_rtld_map).l_tls_blocksize - + align); + + max_align); # else /* In case a model with a different layout for the TCB and DTV is defined add another #elif here and in the following #ifs. */ # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined" # endif /* Align the TLS block. */ - tlsblock = (void *) (((uintptr_t) tlsblock + align - 1) - & ~(align - 1)); + tlsblock = (void *) (((uintptr_t) tlsblock + max_align - 1) + & ~(max_align - 1)); /* Initialize the dtv. */ initdtv[0].counter = 1; @@ -296,7 +299,7 @@ _dl_start_final (void *arg, struct link_map *bootstrap_map_p, initdtv[1].pointer = tlsblock; # elif TLS_DTV_AT_TP GL(dl_rtld_map).l_tls_offset = roundup (TLS_INIT_TCB_SIZE, - phdr[cnt].p_align); + GL(dl_rtld_map).l_tls_align); initdtv[1].pointer = (char *) tlsblock + GL(dl_rtld_map).l_tls_offset); # else # error "Either TLS_TCB_AT_TP or TLS_DTV_AT_TP must be defined" @@ -716,16 +719,18 @@ of this helper program; chances are you did not intend to run this program.\n\ _dl_start_final. But the result is repeatable so do not check for this special but unimportant case. */ GL(dl_loaded)->l_tls_blocksize = ph->p_memsz; + GL(dl_loaded)->l_tls_align = ph->p_align; GL(dl_loaded)->l_tls_initimage_size = ph->p_filesz; GL(dl_loaded)->l_tls_initimage = (void *) (GL(dl_loaded)->l_addr + ph->p_offset); /* This is the first element of the initialization image list. - It is created as a circular list so that we can easily - append to it. */ - GL(dl_initimage_list) = GL(dl_loaded)->l_tls_nextimage = GL(dl_loaded); + We create the list as circular since we have to append at + the end. */ + GL(dl_initimage_list) = GL(dl_loaded)->l_tls_nextimage + = GL(dl_loaded)->l_tls_previmage = GL(dl_loaded); - /* This image get the ID one. */ - GL(dl_tls_module_cnt) = GL(dl_loaded)->l_tls_modid = 1; + /* This image gets the ID one. */ + GL(dl_tls_max_dtv_idx) = GL(dl_loaded)->l_tls_modid = 1; break; #endif } @@ -736,7 +741,7 @@ of this helper program; chances are you did not intend to run this program.\n\ /* We were invoked directly, so the program might not have a PT_INTERP. */ _dl_rtld_libname.name = GL(dl_rtld_map).l_name; - /* _dl_rtld_libname.next = NULL; Alread zero. */ + /* _dl_rtld_libname.next = NULL; Already zero. */ GL(dl_rtld_map).l_libname = &_dl_rtld_libname; } else @@ -973,7 +978,7 @@ of this helper program; chances are you did not intend to run this program.\n\ assert (GL(dl_rtld_map).l_prev->l_next == GL(dl_rtld_map).l_next); GL(dl_rtld_map).l_prev->l_next = &GL(dl_rtld_map); - if (GL(dl_rtld_map).l_next) + if (GL(dl_rtld_map).l_next != NULL) { assert (GL(dl_rtld_map).l_next->l_prev == GL(dl_rtld_map).l_prev); GL(dl_rtld_map).l_next->l_prev = &GL(dl_rtld_map); @@ -1328,6 +1333,41 @@ of this helper program; chances are you did not intend to run this program.\n\ we need it in the memory handling later. */ GL(dl_initial_searchlist) = *GL(dl_main_searchlist); +#ifdef USE_TLS + /* Now it is time to determine the layout of the static TLS block + and allocate it for the initial thread. Note that we always + allocate the static block, we never defer it even if no + DF_STATIC_TLS bit is set. The reason is that we know glibc will + use the static model. First add the dynamic linker to the list + if it also uses TLS. */ + if (GL(dl_rtld_map).l_tls_blocksize != 0) + { + /* At to the list. */ + if (GL(dl_initimage_list) == NULL) + GL(dl_initimage_list) = GL(dl_rtld_map).l_tls_nextimage + = GL(dl_rtld_map).l_tls_previmage = &GL(dl_rtld_map); + else + { + GL(dl_rtld_map).l_tls_nextimage + = GL(dl_initimage_list)->l_tls_nextimage; + GL(dl_rtld_map).l_tls_nextimage->l_tls_previmage + = &GL(dl_rtld_map); + GL(dl_rtld_map).l_tls_previmage = GL(dl_initimage_list); + GL(dl_rtld_map).l_tls_previmage->l_tls_nextimage + = &GL(dl_rtld_map); + GL(dl_initimage_list) = &GL(dl_rtld_map); + } + + /* Assign a module ID. */ + GL(dl_rtld_map).l_tls_modid = _dl_next_tls_modid (); + } + + if (GL(dl_initimage_list) != NULL) + /* This means we actually have some modules which use TLS. + Computer the TLS offsets for the various blocks. */ + _dl_determine_tlsoffset (GL(dl_initimage_list)->l_tls_nextimage); +#endif + { /* Initialize _r_debug. */ struct r_debug *r = _dl_debug_initialize (GL(dl_rtld_map).l_addr); @@ -1344,14 +1384,14 @@ of this helper program; chances are you did not intend to run this program.\n\ #else - if (l->l_info[DT_DEBUG]) + if (l->l_info[DT_DEBUG] != NULL) /* There is a DT_DEBUG entry in the dynamic section. Fill it in with the run-time address of the r_debug structure */ l->l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; /* Fill in the pointer in the dynamic linker's own dynamic section, in case you run gdb on the dynamic linker directly. */ - if (GL(dl_rtld_map).l_info[DT_DEBUG]) + if (GL(dl_rtld_map).l_info[DT_DEBUG] != NULL) GL(dl_rtld_map).l_info[DT_DEBUG]->d_un.d_ptr = (ElfW(Addr)) r; #endif -- cgit 1.4.1