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2020-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2019-09-07Prefer https to http for gnu.org and fsf.org URLsPaul Eggert
Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2018-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
* All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
2017-11-03Mark lazy tlsdesc helper functions unused to avoid warningsSzabolcs Nagy
These static functions are not needed if a target does not do lazy tlsdesc initialization. * elf/tlsdeschtab.h (_dl_tls_resolve_early_return_p): Mark unused. (_dl_tlsdesc_wake_up_held_fixups): Likewise.
2017-08-31elf: Remove internal_function attributeFlorian Weimer
2017-01-01Update copyright dates with scripts/update-copyrights.Joseph Myers
2016-01-04Update copyright dates with scripts/update-copyrights.Joseph Myers
2015-06-17[BZ 18034][AArch64] Lazy TLSDESC relocation data race fixSzabolcs Nagy
Lazy TLSDESC initialization needs to be synchronized with concurrent TLS accesses. The TLS descriptor contains a function pointer (entry) and an argument that is accessed from the entry function. With lazy initialization the first call to the entry function updates the entry and the argument to their final value. A final entry function must make sure that it accesses an initialized argument, this needs synchronization on systems with weak memory ordering otherwise the writes of the first call can be observed out of order. There are at least two issues with the current code: tlsdesc.c (i386, x86_64, arm, aarch64) uses volatile memory accesses on the write side (in the initial entry function) instead of C11 atomics. And on systems with weak memory ordering (arm, aarch64) the read side synchronization is missing from the final entry functions (dl-tlsdesc.S). This patch only deals with aarch64. * Write side: Volatile accesses were replaced with C11 relaxed atomics, and a release store was used for the initialization of entry so the read side can synchronize with it. * Read side: TLS access generated by the compiler and an entry function code is roughly ldr x1, [x0] // load the entry blr x1 // call it entryfunc: ldr x0, [x0,#8] // load the arg ret Various alternatives were considered to force the ordering in the entry function between the two loads: (1) barrier entryfunc: dmb ishld ldr x0, [x0,#8] (2) address dependency (if the address of the second load depends on the result of the first one the ordering is guaranteed): entryfunc: ldr x1,[x0] and x1,x1,#8 orr x1,x1,#8 ldr x0,[x0,x1] (3) load-acquire (ARMv8 instruction that is ordered before subsequent loads and stores) entryfunc: ldar xzr,[x0] ldr x0,[x0,#8] Option (1) is the simplest but slowest (note: this runs at every TLS access), options (2) and (3) do one extra load from [x0] (same address loads are ordered so it happens-after the load on the call site), option (2) clobbers x1 which is problematic because existing gcc does not expect that, so approach (3) was chosen. A new _dl_tlsdesc_return_lazy entry function was introduced for lazily relocated static TLS, so non-lazy static TLS can avoid the synchronization cost. [BZ #18034] * sysdeps/aarch64/dl-tlsdesc.h (_dl_tlsdesc_return_lazy): Declare. * sysdeps/aarch64/dl-tlsdesc.S (_dl_tlsdesc_return_lazy): Define. (_dl_tlsdesc_undefweak): Guarantee TLSDESC entry and argument load-load ordering using ldar. (_dl_tlsdesc_dynamic): Likewise. (_dl_tlsdesc_return_lazy): Likewise. * sysdeps/aarch64/tlsdesc.c (_dl_tlsdesc_resolve_rela_fixup): Use relaxed atomics instead of volatile and synchronize with release store. (_dl_tlsdesc_resolve_hold_fixup): Use relaxed atomics instead of volatile. * elf/tlsdeschtab.h (_dl_tlsdesc_resolve_early_return_p): Likewise.
2015-03-17Fix DTV race, assert, DTV_SURPLUS Static TLS limit, and nptl_db garbageAlexandre Oliva
for ChangeLog [BZ #17090] [BZ #17620] [BZ #17621] [BZ #17628] * NEWS: Update. * elf/dl-tls.c (_dl_update_slotinfo): Clean up outdated DTV entries with Static TLS too. Skip entries past the end of the allocated DTV, from Alan Modra. (tls_get_addr_tail): Update to glibc_likely/unlikely. Move Static TLS DTV entry set up from... (_dl_allocate_tls_init): ... here (fix modid assertion), ... * elf/dl-reloc.c (_dl_nothread_init_static_tls): ... here... * nptl/allocatestack.c (init_one_static_tls): ... and here... * elf/dlopen.c (dl_open_worker): Drop l_tls_modid upper bound for Static TLS. * elf/tlsdeschtab.h (map_generation): Return size_t. Check that the slot we find is associated with the given map before using its generation count. * nptl_db/db_info.c: Include ldsodefs.h. (rtld_global, dtv_slotinfo_list, dtv_slotinfo): New typedefs. * nptl_db/structs.def (DB_RTLD_VARIABLE): New macro. (DB_MAIN_VARIABLE, DB_RTLD_GLOBAL_FIELD): Likewise. (link_map::l_tls_offset): New struct field. (dtv_t::counter): Likewise. (rtld_global): New struct. (_rtld_global): New rtld variable. (dl_tls_dtv_slotinfo_list): New rtld global field. (dtv_slotinfo_list): New struct. (dtv_slotinfo): Likewise. * nptl_db/td_symbol_list.c: Drop gnu/lib-names.h include. (td_lookup): Rename to... (td_mod_lookup): ... this. Use new mod parameter instead of LIBPTHREAD_SO. * nptl_db/td_thr_tlsbase.c: Include link.h. (dtv_slotinfo_list, dtv_slotinfo): New functions. (td_thr_tlsbase): Check DTV generation. Compute Static TLS addresses even if the DTV is out of date or missing them. * nptl_db/fetch-value.c (_td_locate_field): Do not refuse to index zero-length arrays. * nptl_db/thread_dbP.h: Include gnu/lib-names.h. (td_lookup): Make it a macro implemented in terms of... (td_mod_lookup): ... this declaration. * nptl_db/db-symbols.awk (DB_RTLD_VARIABLE): Override. (DB_MAIN_VARIABLE): Likewise.
2015-01-02Update copyright dates with scripts/update-copyrights.Joseph Myers
2014-01-01Update copyright notices with scripts/update-copyrightsAllan McRae
2013-11-13Handle NULL return from htab_find_slot()Marcus Shawcroft
2013-02-07Remove lots of inline keywords.Roland McGrath
2013-01-02Update copyright notices with scripts/update-copyrights.Joseph Myers
2012-02-09Replace FSF snail mail address with URLs.Paul Eggert
2008-05-13Introduce TLS descriptors for i386 and x86_64.Ulrich Drepper
* include/inline-hashtab.h: New file, copied from 2005's libiberty, with fix for memory leak imported afterwards by Glauber de Oliveira Costa. * elf/tlsdeschtab.h: New file. * elf/dl-reloc.c (_dl_try_allocate_static_tls): Extract from... (_dl_allocate_static_tls): ... here. Rearrange failure path. (CHECK_STATIC_TLS): Move to... * elf/dynamic-link.h: ... this file. (TRY_STATIC_TLS): New macro. * elf/dl-conflict.c (CHECK_STATIC_TLS, TRY_STATIC_TLS): Override. * elf/elf.h (R_386_TLS_GOTDESC, R_386_TLS_DESC_CALL, R_386_TLS_DESC): Define. (R_X86_64_PC64, R_X86_GOTOFF64, R_X86_64_GOTPC32): Merge from binutils. (R_X86_64_GOTPC32_TLSDESC, R_X86_64_TLSDESC_CALL, R_X86_64_TLSDESC): Define. (R_386_NUM, R_X86_64_NUM): Adjust. * sysdeps/i386/Makefile (sysdep-dl-routines, sysdep_routines, systep-rtld-routines): Add tlsdesc and dl-tlsdesc for elf subdir. (gen-as-const-headers): Add tlsdesc.sym to csu subdir. * sysdeps/i386/dl-lookupcfg.h: New file. Introduce _dl_unmap to release tlsdesc_table. * sysdeps/i386/dl-machine.h: Include dl-tlsdesc.h. (elf_machine_type_class): Mark R_386_TLS_DESC as PLT class. (elf_machine_rel): Handle R_386_TLS_DESC. (elf_machine_rela): Likewise. (elf_machine_lazy_rel): Likewise. (elf_machine_lazy_rela): Likewise. * sysdeps/i386/dl-tls.h (struct dl_tls_index): Name it. * sysdeps/i386/dl-tlsdesc.S: New file. * sysdeps/i386/dl-tlsdesc.h: New file. * sysdeps/i386/tlsdesc.c: New file. * sysdeps/i386/tlsdesc.sym: New file. * sysdeps/i386/bits/linkmap.h (struct link_map_machine): Add tlsdesc_table. * sysdeps/x86_64/Makefile (sysdep-dl-routines, sysdep_routines, systep-rtld-routines): Add tlsdesc and dl-tlsdesc for elf subdir. (gen-as-const-headers): Add tlsdesc.sym to csu subdir. * sysdeps/x86_64/dl-lookupcfg.h: New file. Introduce _dl_unmap to release tlsdesc_table. * sysdeps/x86_64/dl-machine.h: Include dl-tlsdesc.h. (elf_machine_runtime_setup): Set up lazy TLSDESC GOT entry. (elf_machine_type_class): Mark R_X86_64_TLSDESC as PLT class. (elf_machine_rel): Handle R_X86_64_TLSDESC. (elf_machine_rela): Likewise. (elf_machine_lazy_rel): Likewise. * sysdeps/x86_64/dl-tls.h (struct dl_tls_index): Name it. (__tls_get_addr): Do not declare for non-shared compiles. * sysdeps/x86_64/dl-tlsdesc.S: New file. * sysdeps/x86_64/dl-tlsdesc.h: New file. * sysdeps/x86_64/tlsdesc.c: New file. * sysdeps/x86_64/tlsdesc.sym: New file. * sysdeps/x86_64/bits/linkmap.h (struct link_map_machine): Add tlsdesc_table for both 32- and 64-bit structs.