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* Remove --enable-tunables configure optionAdhemerval Zanella Netto2023-03-291-5/+3
| | | | | | | | | | | | And make always supported. The configure option was added on glibc 2.25 and some features require it (such as hwcap mask, huge pages support, and lock elisition tuning). It also simplifies the build permutations. Changes from v1: * Remove glibc.rtld.dynamic_sort changes, it is orthogonal and needs more discussion. * Cleanup more code. Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
* Update copyright dates with scripts/update-copyrightsJoseph Myers2023-01-061-1/+1
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* x86: use default cache size if it cannot be determined [BZ #28784]Aurelien Jarno2022-01-171-4/+10
| | | | | | | | | | | | | | | | | | | | | | In some cases (e.g QEMU, non-Intel/AMD CPU) the cache information can not be retrieved and the corresponding values are set to 0. Commit 2d651eb9265d ("x86: Move x86 processor cache info to cpu_features") changed the behaviour in such case by defining the __x86_shared_cache_size and __x86_data_cache_size variables to 0 instead of using the default values. This cause an issue with the i686 SSE2 optimized bzero/routine which assumes that the cache size is at least 128 bytes, and otherwise tries to zero/set the whole address space minus 128 bytes. Fix that by restoring the original code to only update __x86_shared_cache_size and __x86_data_cache_size variables if the corresponding cache sizes are not zero. Fixes bug 28784 Fixes commit 2d651eb9265d 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
* x86-64: Add Avoid_Short_Distance_REP_MOVSBH.J. Lu2021-07-281-0/+9
| | | | | | | | | | | | | | | | | | | | | | | | commit 3ec5d83d2a237d39e7fd6ef7a0bc8ac4c171a4a5 Author: H.J. Lu <hjl.tools@gmail.com> Date: Sat Jan 25 14:19:40 2020 -0800 x86-64: Avoid rep movsb with short distance [BZ #27130] introduced some regressions on Intel processors without Fast Short REP MOV (FSRM). Add Avoid_Short_Distance_REP_MOVSB to avoid rep movsb with short distance only on Intel processors with FSRM. bench-memmove-large on Skylake server shows that cycles of __memmove_evex_unaligned_erms improves for the following data size: before after Improvement length=4127, align1=3, align2=0: 479.38 349.25 27% length=4223, align1=9, align2=5: 405.62 333.25 18% length=8223, align1=3, align2=0: 786.12 496.38 37% length=8319, align1=9, align2=5: 727.50 501.38 31% length=16415, align1=3, align2=0: 1436.88 840.00 41% length=16511, align1=9, align2=5: 1375.50 836.38 39% length=32799, align1=3, align2=0: 2890.00 1860.12 36% length=32895, align1=9, align2=5: 2891.38 1931.88 33%
* x86: Remove unused variables for raw cache sizes from cacheinfo.hFlorian Weimer2021-02-221-12/+0
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* x86: Adding an upper bound for Enhanced REP MOVSB.Sajan Karumanchi2021-02-021-0/+4
| | | | | | | | | | | | | | | In the process of optimizing memcpy for AMD machines, we have found the vector move operations are outperforming enhanced REP MOVSB for data transfers above the L2 cache size on Zen3 architectures. To handle this use case, we are adding an upper bound parameter on enhanced REP MOVSB:'__x86_rep_movsb_stop_threshold'. As per large-bench results, we are configuring this parameter to the L2 cache size for AMD machines and applicable from Zen3 architecture supporting the ERMS feature. For architectures other than AMD, it is the computed value of non-temporal threshold parameter. Reviewed-by: Premachandra Mallappa <premachandra.mallappa@amd.com>
* x86: Move x86 processor cache info to cpu_featuresH.J. Lu2021-01-141-373/+27
| | | | | | | | | | | 1. Move x86 processor cache info to _dl_x86_cpu_features in ld.so. 2. Update tunable bounds with TUNABLE_SET_WITH_BOUNDS. 3. Move x86 cache info initialization to dl-cacheinfo.h and initialize x86 cache info in init_cpu_features (). 4. Put x86 cache info for libc in cacheinfo.h, which is included in libc-start.c in libc.a and is included in cacheinfo.c in libc.so. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* 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: Restore processing of cache size tunables in init_cacheinfoFlorian Weimer2020-10-281-8/+4
| | | | | Fixes and partially reverts commit 59803e81f96b479c17f583b31eac44b5 ("x86: Optimizing memcpy for AMD Zen architecture.").
* x86: Optimizing memcpy for AMD Zen architecture.Sajan Karumanchi2020-10-281-6/+26
| | | | | | | | | | | | | | Modifying the shareable cache '__x86_shared_cache_size', which is a factor in computing the non-temporal threshold parameter '__x86_shared_non_temporal_threshold' to optimize memcpy for AMD Zen architectures. In the existing implementation, the shareable cache is computed as 'L3 per thread, L2 per core'. Recomputing this shareable cache as 'L3 per CCX(Core-Complex)' has brought in performance gains. As per the large bench variant results, this patch also addresses the regression problem on AMD Zen architectures. Reviewed-by: Premachandra Mallappa <premachandra.mallappa@amd.com>
* x86: Initialize CPU info via IFUNC relocation [BZ 26203]H.J. Lu2020-10-161-0/+413
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.