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* x86: Add x86-64-vN check to early startupFlorian Weimer2022-01-141-1/+30
| | | | | | | | This ISA level covers the glibc build itself. <dl-hwcap-check.h> cannot be used because this check (by design) happens before DL_PLATFORM_INIT and the x86 CPU flags initialization. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2022-01-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
* Fix misplaced constAndreas Schwab2021-01-251-1/+1
| | | | | Constify __x86_cacheinfo_p and __x86_cpu_features_p, not their pointer target types.
* <sys/platform/x86.h>: Remove the C preprocessor magicH.J. Lu2021-01-211-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In <sys/platform/x86.h>, define CPU features as enum instead of using the C preprocessor magic to make it easier to wrap this functionality in other languages. Move the C preprocessor magic to internal header for better GCC codegen when more than one features are checked in a single expression as in x86-64 dl-hwcaps-subdirs.c. 1. Rename COMMON_CPUID_INDEX_XXX to CPUID_INDEX_XXX. 2. Move CPUID_INDEX_MAX to sysdeps/x86/include/cpu-features.h. 3. Remove struct cpu_features and __x86_get_cpu_features from <sys/platform/x86.h>. 4. Add __x86_get_cpuid_feature_leaf to <sys/platform/x86.h> and put it in libc. 5. Make __get_cpu_features() private to glibc. 6. Replace __x86_get_cpu_features(N) with __get_cpu_features(). 7. Add _dl_x86_get_cpu_features to GLIBC_PRIVATE. 8. Use a single enum index for each CPU feature detection. 9. Pass the CPUID feature leaf to __x86_get_cpuid_feature_leaf. 10. Return zero struct cpuid_feature for the older glibc binary with a smaller CPUID_INDEX_MAX [BZ #27104]. 11. Inside glibc, use the C preprocessor magic so that cpu_features data can be loaded just once leading to more compact code for glibc. 256 bits are used for each CPUID leaf. Some leaves only contain a few features. We can add exceptions to such leaves. But it will increase code sizes and it is harder to provide backward/forward compatibilities when new features are added to such leaves in the future. When new leaves are added, _rtld_global_ro offsets will change which leads to race condition during in-place updates. We may avoid in-place updates by 1. Rename the old glibc. 2. Install the new glibc. 3. Remove the old glibc. NB: A function, __x86_get_cpuid_feature_leaf , is used to avoid the copy relocation issue with IFUNC resolver as shown in IFUNC resolver tests.
* Update copyright dates with scripts/update-copyrightsPaul Eggert2021-01-021-1/+1
| | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 6694 files FOO. I then removed trailing white space from benchtests/bench-pthread-locks.c and iconvdata/tst-iconv-big5-hkscs-to-2ucs4.c, to work around this diagnostic from Savannah: remote: *** pre-commit check failed ... remote: *** error: lines with trailing whitespace found remote: error: hook declined to update refs/heads/master
* x86: Initialize CPU info via IFUNC relocation [BZ 26203]H.J. Lu2020-10-161-1/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | X86 CPU features in ld.so are initialized by init_cpu_features, which is invoked by DL_PLATFORM_INIT from _dl_sysdep_start. But when ld.so is loaded by static executable, DL_PLATFORM_INIT is never called. Also x86 cache info in libc.o and libc.a is initialized by a constructor which may be called too late. Since some fields in _rtld_global_ro in ld.so are initialized by dynamic relocation, we can also initialize x86 CPU features in _rtld_global_ro in ld.so and cache info in libc.so by initializing dummy function pointers in ld.so and libc.so via IFUNC relocation. Key points: 1. IFUNC is always supported, independent of --enable-multi-arch or --disable-multi-arch. Linker generates IFUNC relocations from input IFUNC objects and ld.so performs IFUNC relocations. 2. There are no IFUNC dependencies in ld.so before dynamic relocation have been performed, 3. The x86 CPU features in ld.so is initialized by DL_PLATFORM_INIT in dynamic executable and by IFUNC relocation in dlopen in static executable. 4. The x86 cache info in libc.o is initialized by IFUNC relocation. 5. In libc.a, both x86 CPU features and cache info are initialized from ARCH_INIT_CPU_FEATURES, not by IFUNC relocation, before __libc_early_init is called. Note: _dl_x86_init_cpu_features can be called more than once from DL_PLATFORM_INIT and during relocation in ld.so.
* x86: Install <sys/platform/x86.h> [BZ #26124]H.J. Lu2020-09-111-2/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Install <sys/platform/x86.h> so that programmers can do #if __has_include(<sys/platform/x86.h>) #include <sys/platform/x86.h> #endif ... if (CPU_FEATURE_USABLE (SSE2)) ... if (CPU_FEATURE_USABLE (AVX2)) ... <sys/platform/x86.h> exports only: enum { COMMON_CPUID_INDEX_1 = 0, COMMON_CPUID_INDEX_7, COMMON_CPUID_INDEX_80000001, COMMON_CPUID_INDEX_D_ECX_1, COMMON_CPUID_INDEX_80000007, COMMON_CPUID_INDEX_80000008, COMMON_CPUID_INDEX_7_ECX_1, /* Keep the following line at the end. */ COMMON_CPUID_INDEX_MAX }; struct cpuid_features { struct cpuid_registers cpuid; struct cpuid_registers usable; }; struct cpu_features { struct cpu_features_basic basic; struct cpuid_features features[COMMON_CPUID_INDEX_MAX]; }; /* Get a pointer to the CPU features structure. */ extern const struct cpu_features *__x86_get_cpu_features (unsigned int max) __attribute__ ((const)); Since all feature checks are done through macros, programs compiled with a newer <sys/platform/x86.h> are compatible with the older glibc binaries as long as the layout of struct cpu_features is identical. The features array can be expanded with backward binary compatibility for both .o and .so files. When COMMON_CPUID_INDEX_MAX is increased to support new processor features, __x86_get_cpu_features in the older glibc binaries returns NULL and HAS_CPU_FEATURE/CPU_FEATURE_USABLE return false on the new processor feature. No new symbol version is neeeded. Both CPU_FEATURE_USABLE and HAS_CPU_FEATURE are provided. HAS_CPU_FEATURE can be used to identify processor features. Note: Although GCC has __builtin_cpu_supports, it only supports a subset of <sys/platform/x86.h> and it is equivalent to CPU_FEATURE_USABLE. It doesn't support HAS_CPU_FEATURE.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2020-01-011-1/+1
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* Prefer https to http for gnu.org and fsf.org URLsPaul Eggert2019-09-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* Update copyright dates with scripts/update-copyrights.Joseph Myers2019-01-011-1/+1
| | | | | | | * 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.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+1
| | | | | | | * 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.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2017-01-011-1/+1
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* Update copyright dates with scripts/update-copyrights.Joseph Myers2016-01-041-1/+1
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* Add _dl_x86_cpu_features to rtld_globalH.J. Lu2015-08-131-0/+27
This patch adds _dl_x86_cpu_features to rtld_global in x86 ld.so and initializes it early before __libc_start_main is called so that cpu_features is always available when it is used and we can avoid calling __init_cpu_features in IFUNC selectors. * sysdeps/i386/dl-machine.h: Include <cpu-features.c>. (dl_platform_init): Call init_cpu_features. * sysdeps/i386/dl-procinfo.c (_dl_x86_cpu_features): New. * sysdeps/i386/i686/cacheinfo.c (DISABLE_PREFERRED_MEMORY_INSTRUCTION): Removed. * sysdeps/i386/i686/multiarch/Makefile (aux): Remove init-arch. * sysdeps/i386/i686/multiarch/Versions: Removed. * sysdeps/i386/i686/multiarch/ifunc-defines.sym (KIND_OFFSET): Removed. * sysdeps/i386/ldsodefs.h: Include <cpu-features.h>. * sysdeps/unix/sysv/linux/x86/Makefile (libpthread-sysdep_routines): Remove init-arch. * sysdeps/unix/sysv/linux/x86_64/dl-procinfo.c: Include <sysdeps/x86_64/dl-procinfo.c> instead of sysdeps/generic/dl-procinfo.c>. * sysdeps/x86/Makefile [$(subdir) == csu] (gen-as-const-headers): Add cpu-features-offsets.sym and rtld-global-offsets.sym. [$(subdir) == elf] (sysdep-dl-routines): Add dl-get-cpu-features. [$(subdir) == elf] (tests): Add tst-get-cpu-features. [$(subdir) == elf] (tests-static): Add tst-get-cpu-features-static. * sysdeps/x86/Versions: New file. * sysdeps/x86/cpu-features-offsets.sym: Likewise. * sysdeps/x86/cpu-features.c: Likewise. * sysdeps/x86/cpu-features.h: Likewise. * sysdeps/x86/dl-get-cpu-features.c: Likewise. * sysdeps/x86/libc-start.c: Likewise. * sysdeps/x86/rtld-global-offsets.sym: Likewise. * sysdeps/x86/tst-get-cpu-features-static.c: Likewise. * sysdeps/x86/tst-get-cpu-features.c: Likewise. * sysdeps/x86_64/dl-procinfo.c: Likewise. * sysdeps/x86_64/cacheinfo.c (__cpuid_count): Removed. Assume USE_MULTIARCH is defined and don't check it. (is_intel): Replace __cpu_features with GLRO(dl_x86_cpu_features). (is_amd): Likewise. (max_cpuid): Likewise. (intel_check_word): Likewise. (__cache_sysconf): Don't call __init_cpu_features. (__x86_preferred_memory_instruction): Removed. (init_cacheinfo): Don't call __init_cpu_features. Replace __cpu_features with GLRO(dl_x86_cpu_features). * sysdeps/x86_64/dl-machine.h: <cpu-features.c>. (dl_platform_init): Call init_cpu_features. * sysdeps/x86_64/ldsodefs.h: Include <cpu-features.h>. * sysdeps/x86_64/multiarch/Makefile (aux): Remove init-arch. * sysdeps/x86_64/multiarch/Versions: Removed. * sysdeps/x86_64/multiarch/cacheinfo.c: Likewise. * sysdeps/x86_64/multiarch/init-arch.c: Likewise. * sysdeps/x86_64/multiarch/ifunc-defines.sym (KIND_OFFSET): Removed. * sysdeps/x86_64/multiarch/init-arch.h: Rewrite.