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6a824767d8
Since the maximum CPUID level of older Intel CPUs is 1, change handle_intel to return -1, instead of assert, when the maximum CPUID level is less than 2. [BZ #20647] * sysdeps/x86/cacheinfo.c (handle_intel): Return -1 if the maximum CPUID level is less than 2.
772 lines
21 KiB
C
772 lines
21 KiB
C
/* x86_64 cache info.
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Copyright (C) 2003-2016 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<http://www.gnu.org/licenses/>. */
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#include <assert.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <cpuid.h>
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#include <init-arch.h>
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#define is_intel GLRO(dl_x86_cpu_features).kind == arch_kind_intel
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#define is_amd GLRO(dl_x86_cpu_features).kind == arch_kind_amd
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#define max_cpuid GLRO(dl_x86_cpu_features).max_cpuid
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static const struct intel_02_cache_info
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{
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unsigned char idx;
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unsigned char assoc;
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unsigned char linesize;
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unsigned char rel_name;
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unsigned int size;
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} intel_02_known [] =
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{
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#define M(sc) ((sc) - _SC_LEVEL1_ICACHE_SIZE)
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{ 0x06, 4, 32, M(_SC_LEVEL1_ICACHE_SIZE), 8192 },
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{ 0x08, 4, 32, M(_SC_LEVEL1_ICACHE_SIZE), 16384 },
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{ 0x09, 4, 32, M(_SC_LEVEL1_ICACHE_SIZE), 32768 },
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{ 0x0a, 2, 32, M(_SC_LEVEL1_DCACHE_SIZE), 8192 },
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{ 0x0c, 4, 32, M(_SC_LEVEL1_DCACHE_SIZE), 16384 },
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{ 0x0d, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 16384 },
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{ 0x0e, 6, 64, M(_SC_LEVEL1_DCACHE_SIZE), 24576 },
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{ 0x21, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 },
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{ 0x22, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 524288 },
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{ 0x23, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 1048576 },
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{ 0x25, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 },
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{ 0x29, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 },
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{ 0x2c, 8, 64, M(_SC_LEVEL1_DCACHE_SIZE), 32768 },
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{ 0x30, 8, 64, M(_SC_LEVEL1_ICACHE_SIZE), 32768 },
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{ 0x39, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 131072 },
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{ 0x3a, 6, 64, M(_SC_LEVEL2_CACHE_SIZE), 196608 },
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{ 0x3b, 2, 64, M(_SC_LEVEL2_CACHE_SIZE), 131072 },
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{ 0x3c, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 },
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{ 0x3d, 6, 64, M(_SC_LEVEL2_CACHE_SIZE), 393216 },
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{ 0x3e, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x3f, 2, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 },
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{ 0x41, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 131072 },
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{ 0x42, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 262144 },
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{ 0x43, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x44, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 1048576 },
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{ 0x45, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 2097152 },
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{ 0x46, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 },
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{ 0x47, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 },
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{ 0x48, 12, 64, M(_SC_LEVEL2_CACHE_SIZE), 3145728 },
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{ 0x49, 16, 64, M(_SC_LEVEL2_CACHE_SIZE), 4194304 },
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{ 0x4a, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 6291456 },
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{ 0x4b, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 },
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{ 0x4c, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 12582912 },
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{ 0x4d, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 16777216 },
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{ 0x4e, 24, 64, M(_SC_LEVEL2_CACHE_SIZE), 6291456 },
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{ 0x60, 8, 64, M(_SC_LEVEL1_DCACHE_SIZE), 16384 },
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{ 0x66, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 8192 },
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{ 0x67, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 16384 },
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{ 0x68, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 32768 },
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{ 0x78, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 1048576 },
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{ 0x79, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 131072 },
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{ 0x7a, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 },
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{ 0x7b, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x7c, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 1048576 },
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{ 0x7d, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 2097152 },
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{ 0x7f, 2, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x80, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x82, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 262144 },
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{ 0x83, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x84, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 1048576 },
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{ 0x85, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 2097152 },
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{ 0x86, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 },
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{ 0x87, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 1048576 },
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{ 0xd0, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 524288 },
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{ 0xd1, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 1048576 },
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{ 0xd2, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 },
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{ 0xd6, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 1048576 },
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{ 0xd7, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 },
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{ 0xd8, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 },
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{ 0xdc, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 },
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{ 0xdd, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 },
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{ 0xde, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 },
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{ 0xe2, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 },
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{ 0xe3, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 },
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{ 0xe4, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 },
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{ 0xea, 24, 64, M(_SC_LEVEL3_CACHE_SIZE), 12582912 },
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{ 0xeb, 24, 64, M(_SC_LEVEL3_CACHE_SIZE), 18874368 },
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{ 0xec, 24, 64, M(_SC_LEVEL3_CACHE_SIZE), 25165824 },
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};
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#define nintel_02_known (sizeof (intel_02_known) / sizeof (intel_02_known [0]))
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static int
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intel_02_known_compare (const void *p1, const void *p2)
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{
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const struct intel_02_cache_info *i1;
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const struct intel_02_cache_info *i2;
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i1 = (const struct intel_02_cache_info *) p1;
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i2 = (const struct intel_02_cache_info *) p2;
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if (i1->idx == i2->idx)
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return 0;
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return i1->idx < i2->idx ? -1 : 1;
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}
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static long int
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__attribute__ ((noinline))
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intel_check_word (int name, unsigned int value, bool *has_level_2,
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bool *no_level_2_or_3)
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{
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if ((value & 0x80000000) != 0)
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/* The register value is reserved. */
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return 0;
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/* Fold the name. The _SC_ constants are always in the order SIZE,
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ASSOC, LINESIZE. */
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int folded_rel_name = (M(name) / 3) * 3;
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while (value != 0)
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{
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unsigned int byte = value & 0xff;
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if (byte == 0x40)
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{
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*no_level_2_or_3 = true;
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if (folded_rel_name == M(_SC_LEVEL3_CACHE_SIZE))
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/* No need to look further. */
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break;
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}
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else if (byte == 0xff)
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{
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/* CPUID leaf 0x4 contains all the information. We need to
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iterate over it. */
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unsigned int eax;
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unsigned int ebx;
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unsigned int ecx;
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unsigned int edx;
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unsigned int round = 0;
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while (1)
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{
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__cpuid_count (4, round, eax, ebx, ecx, edx);
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enum { null = 0, data = 1, inst = 2, uni = 3 } type = eax & 0x1f;
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if (type == null)
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/* That was the end. */
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break;
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unsigned int level = (eax >> 5) & 0x7;
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if ((level == 1 && type == data
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&& folded_rel_name == M(_SC_LEVEL1_DCACHE_SIZE))
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|| (level == 1 && type == inst
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&& folded_rel_name == M(_SC_LEVEL1_ICACHE_SIZE))
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|| (level == 2 && folded_rel_name == M(_SC_LEVEL2_CACHE_SIZE))
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|| (level == 3 && folded_rel_name == M(_SC_LEVEL3_CACHE_SIZE))
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|| (level == 4 && folded_rel_name == M(_SC_LEVEL4_CACHE_SIZE)))
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{
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unsigned int offset = M(name) - folded_rel_name;
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if (offset == 0)
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/* Cache size. */
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return (((ebx >> 22) + 1)
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* (((ebx >> 12) & 0x3ff) + 1)
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* ((ebx & 0xfff) + 1)
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* (ecx + 1));
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if (offset == 1)
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return (ebx >> 22) + 1;
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assert (offset == 2);
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return (ebx & 0xfff) + 1;
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}
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++round;
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}
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/* There is no other cache information anywhere else. */
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break;
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}
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else
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{
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if (byte == 0x49 && folded_rel_name == M(_SC_LEVEL3_CACHE_SIZE))
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{
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/* Intel reused this value. For family 15, model 6 it
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specifies the 3rd level cache. Otherwise the 2nd
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level cache. */
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unsigned int family = GLRO(dl_x86_cpu_features).family;
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unsigned int model = GLRO(dl_x86_cpu_features).model;
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if (family == 15 && model == 6)
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{
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/* The level 3 cache is encoded for this model like
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the level 2 cache is for other models. Pretend
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the caller asked for the level 2 cache. */
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name = (_SC_LEVEL2_CACHE_SIZE
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+ (name - _SC_LEVEL3_CACHE_SIZE));
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folded_rel_name = M(_SC_LEVEL2_CACHE_SIZE);
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}
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}
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struct intel_02_cache_info *found;
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struct intel_02_cache_info search;
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search.idx = byte;
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found = bsearch (&search, intel_02_known, nintel_02_known,
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sizeof (intel_02_known[0]), intel_02_known_compare);
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if (found != NULL)
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{
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if (found->rel_name == folded_rel_name)
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{
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unsigned int offset = M(name) - folded_rel_name;
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if (offset == 0)
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/* Cache size. */
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return found->size;
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if (offset == 1)
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return found->assoc;
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assert (offset == 2);
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return found->linesize;
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}
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if (found->rel_name == M(_SC_LEVEL2_CACHE_SIZE))
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*has_level_2 = true;
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}
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}
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/* Next byte for the next round. */
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value >>= 8;
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}
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/* Nothing found. */
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return 0;
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}
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static long int __attribute__ ((noinline))
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handle_intel (int name, unsigned int maxidx)
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{
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/* Return -1 for older CPUs. */
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if (maxidx < 2)
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return -1;
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/* OK, we can use the CPUID instruction to get all info about the
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caches. */
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unsigned int cnt = 0;
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unsigned int max = 1;
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long int result = 0;
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bool no_level_2_or_3 = false;
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bool has_level_2 = false;
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while (cnt++ < max)
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{
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unsigned int eax;
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unsigned int ebx;
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unsigned int ecx;
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unsigned int edx;
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__cpuid (2, eax, ebx, ecx, edx);
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/* The low byte of EAX in the first round contain the number of
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rounds we have to make. At least one, the one we are already
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doing. */
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if (cnt == 1)
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{
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max = eax & 0xff;
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eax &= 0xffffff00;
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}
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/* Process the individual registers' value. */
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result = intel_check_word (name, eax, &has_level_2, &no_level_2_or_3);
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if (result != 0)
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return result;
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result = intel_check_word (name, ebx, &has_level_2, &no_level_2_or_3);
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if (result != 0)
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return result;
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result = intel_check_word (name, ecx, &has_level_2, &no_level_2_or_3);
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if (result != 0)
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return result;
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result = intel_check_word (name, edx, &has_level_2, &no_level_2_or_3);
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if (result != 0)
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return result;
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}
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if (name >= _SC_LEVEL2_CACHE_SIZE && name <= _SC_LEVEL3_CACHE_LINESIZE
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&& no_level_2_or_3)
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return -1;
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return 0;
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}
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static long int __attribute__ ((noinline))
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handle_amd (int name)
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{
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unsigned int eax;
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unsigned int ebx;
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unsigned int ecx;
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unsigned int edx;
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__cpuid (0x80000000, eax, ebx, ecx, edx);
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/* No level 4 cache (yet). */
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if (name > _SC_LEVEL3_CACHE_LINESIZE)
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return 0;
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unsigned int fn = 0x80000005 + (name >= _SC_LEVEL2_CACHE_SIZE);
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if (eax < fn)
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return 0;
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__cpuid (fn, eax, ebx, ecx, edx);
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if (name < _SC_LEVEL1_DCACHE_SIZE)
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{
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name += _SC_LEVEL1_DCACHE_SIZE - _SC_LEVEL1_ICACHE_SIZE;
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ecx = edx;
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}
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switch (name)
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{
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case _SC_LEVEL1_DCACHE_SIZE:
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return (ecx >> 14) & 0x3fc00;
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case _SC_LEVEL1_DCACHE_ASSOC:
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ecx >>= 16;
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if ((ecx & 0xff) == 0xff)
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/* Fully associative. */
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return (ecx << 2) & 0x3fc00;
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return ecx & 0xff;
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case _SC_LEVEL1_DCACHE_LINESIZE:
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return ecx & 0xff;
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case _SC_LEVEL2_CACHE_SIZE:
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return (ecx & 0xf000) == 0 ? 0 : (ecx >> 6) & 0x3fffc00;
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case _SC_LEVEL2_CACHE_ASSOC:
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switch ((ecx >> 12) & 0xf)
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{
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case 0:
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case 1:
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case 2:
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case 4:
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return (ecx >> 12) & 0xf;
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case 6:
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return 8;
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case 8:
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return 16;
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case 10:
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return 32;
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case 11:
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return 48;
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case 12:
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return 64;
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case 13:
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return 96;
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case 14:
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return 128;
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case 15:
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return ((ecx >> 6) & 0x3fffc00) / (ecx & 0xff);
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default:
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return 0;
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}
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/* NOTREACHED */
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case _SC_LEVEL2_CACHE_LINESIZE:
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return (ecx & 0xf000) == 0 ? 0 : ecx & 0xff;
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case _SC_LEVEL3_CACHE_SIZE:
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return (edx & 0xf000) == 0 ? 0 : (edx & 0x3ffc0000) << 1;
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case _SC_LEVEL3_CACHE_ASSOC:
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switch ((edx >> 12) & 0xf)
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{
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case 0:
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case 1:
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case 2:
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case 4:
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return (edx >> 12) & 0xf;
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case 6:
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return 8;
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case 8:
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return 16;
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case 10:
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return 32;
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case 11:
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return 48;
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case 12:
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return 64;
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case 13:
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return 96;
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case 14:
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return 128;
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case 15:
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return ((edx & 0x3ffc0000) << 1) / (edx & 0xff);
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default:
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return 0;
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}
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/* NOTREACHED */
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case _SC_LEVEL3_CACHE_LINESIZE:
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return (edx & 0xf000) == 0 ? 0 : edx & 0xff;
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default:
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assert (! "cannot happen");
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}
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return -1;
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}
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/* Get the value of the system variable NAME. */
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long int
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attribute_hidden
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__cache_sysconf (int name)
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{
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if (is_intel)
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return handle_intel (name, max_cpuid);
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if (is_amd)
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return handle_amd (name);
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// XXX Fill in more vendors.
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/* CPU not known, we have no information. */
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return 0;
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}
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/* Data cache size for use in memory and string routines, typically
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L1 size, rounded to multiple of 256 bytes. */
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long int __x86_data_cache_size_half attribute_hidden = 32 * 1024 / 2;
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long int __x86_data_cache_size attribute_hidden = 32 * 1024;
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/* Similar to __x86_data_cache_size_half, but not rounded. */
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long int __x86_raw_data_cache_size_half attribute_hidden = 32 * 1024 / 2;
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/* Similar to __x86_data_cache_size, but not rounded. */
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long int __x86_raw_data_cache_size attribute_hidden = 32 * 1024;
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/* Shared cache size for use in memory and string routines, typically
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L2 or L3 size, rounded to multiple of 256 bytes. */
|
|
long int __x86_shared_cache_size_half attribute_hidden = 1024 * 1024 / 2;
|
|
long int __x86_shared_cache_size attribute_hidden = 1024 * 1024;
|
|
/* Similar to __x86_shared_cache_size_half, but not rounded. */
|
|
long int __x86_raw_shared_cache_size_half attribute_hidden = 1024 * 1024 / 2;
|
|
/* Similar to __x86_shared_cache_size, but not rounded. */
|
|
long int __x86_raw_shared_cache_size attribute_hidden = 1024 * 1024;
|
|
|
|
/* Threshold to use non temporal store. */
|
|
long int __x86_shared_non_temporal_threshold attribute_hidden;
|
|
|
|
#ifndef DISABLE_PREFETCHW
|
|
/* PREFETCHW support flag for use in memory and string routines. */
|
|
int __x86_prefetchw attribute_hidden;
|
|
#endif
|
|
|
|
|
|
static void
|
|
__attribute__((constructor))
|
|
init_cacheinfo (void)
|
|
{
|
|
/* Find out what brand of processor. */
|
|
unsigned int eax;
|
|
unsigned int ebx;
|
|
unsigned int ecx;
|
|
unsigned int edx;
|
|
int max_cpuid_ex;
|
|
long int data = -1;
|
|
long int shared = -1;
|
|
unsigned int level;
|
|
unsigned int threads = 0;
|
|
|
|
if (is_intel)
|
|
{
|
|
data = handle_intel (_SC_LEVEL1_DCACHE_SIZE, max_cpuid);
|
|
|
|
long int core = handle_intel (_SC_LEVEL2_CACHE_SIZE, max_cpuid);
|
|
bool inclusive_cache = true;
|
|
|
|
/* Try L3 first. */
|
|
level = 3;
|
|
shared = handle_intel (_SC_LEVEL3_CACHE_SIZE, max_cpuid);
|
|
|
|
/* Number of logical processors sharing L2 cache. */
|
|
int threads_l2;
|
|
|
|
/* Number of logical processors sharing L3 cache. */
|
|
int threads_l3;
|
|
|
|
if (shared <= 0)
|
|
{
|
|
/* Try L2 otherwise. */
|
|
level = 2;
|
|
shared = core;
|
|
threads_l2 = 0;
|
|
threads_l3 = -1;
|
|
}
|
|
else
|
|
{
|
|
threads_l2 = 0;
|
|
threads_l3 = 0;
|
|
}
|
|
|
|
/* A value of 0 for the HTT bit indicates there is only a single
|
|
logical processor. */
|
|
if (HAS_CPU_FEATURE (HTT))
|
|
{
|
|
/* Figure out the number of logical threads that share the
|
|
highest cache level. */
|
|
if (max_cpuid >= 4)
|
|
{
|
|
unsigned int family = GLRO(dl_x86_cpu_features).family;
|
|
unsigned int model = GLRO(dl_x86_cpu_features).model;
|
|
|
|
int i = 0;
|
|
|
|
/* Query until cache level 2 and 3 are enumerated. */
|
|
int check = 0x1 | (threads_l3 == 0) << 1;
|
|
do
|
|
{
|
|
__cpuid_count (4, i++, eax, ebx, ecx, edx);
|
|
|
|
/* There seems to be a bug in at least some Pentium Ds
|
|
which sometimes fail to iterate all cache parameters.
|
|
Do not loop indefinitely here, stop in this case and
|
|
assume there is no such information. */
|
|
if ((eax & 0x1f) == 0)
|
|
goto intel_bug_no_cache_info;
|
|
|
|
switch ((eax >> 5) & 0x7)
|
|
{
|
|
default:
|
|
break;
|
|
case 2:
|
|
if ((check & 0x1))
|
|
{
|
|
/* Get maximum number of logical processors
|
|
sharing L2 cache. */
|
|
threads_l2 = (eax >> 14) & 0x3ff;
|
|
check &= ~0x1;
|
|
}
|
|
break;
|
|
case 3:
|
|
if ((check & (0x1 << 1)))
|
|
{
|
|
/* Get maximum number of logical processors
|
|
sharing L3 cache. */
|
|
threads_l3 = (eax >> 14) & 0x3ff;
|
|
|
|
/* Check if L2 and L3 caches are inclusive. */
|
|
inclusive_cache = (edx & 0x2) != 0;
|
|
check &= ~(0x1 << 1);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
while (check);
|
|
|
|
/* If max_cpuid >= 11, THREADS_L2/THREADS_L3 are the maximum
|
|
numbers of addressable IDs for logical processors sharing
|
|
the cache, instead of the maximum number of threads
|
|
sharing the cache. */
|
|
if (max_cpuid >= 11)
|
|
{
|
|
/* Find the number of logical processors shipped in
|
|
one core and apply count mask. */
|
|
i = 0;
|
|
|
|
/* Count SMT only if there is L3 cache. Always count
|
|
core if there is no L3 cache. */
|
|
int count = ((threads_l2 > 0 && level == 3)
|
|
| ((threads_l3 > 0
|
|
|| (threads_l2 > 0 && level == 2)) << 1));
|
|
|
|
while (count)
|
|
{
|
|
__cpuid_count (11, i++, eax, ebx, ecx, edx);
|
|
|
|
int shipped = ebx & 0xff;
|
|
int type = ecx & 0xff00;
|
|
if (shipped == 0 || type == 0)
|
|
break;
|
|
else if (type == 0x100)
|
|
{
|
|
/* Count SMT. */
|
|
if ((count & 0x1))
|
|
{
|
|
int count_mask;
|
|
|
|
/* Compute count mask. */
|
|
asm ("bsr %1, %0"
|
|
: "=r" (count_mask) : "g" (threads_l2));
|
|
count_mask = ~(-1 << (count_mask + 1));
|
|
threads_l2 = (shipped - 1) & count_mask;
|
|
count &= ~0x1;
|
|
}
|
|
}
|
|
else if (type == 0x200)
|
|
{
|
|
/* Count core. */
|
|
if ((count & (0x1 << 1)))
|
|
{
|
|
int count_mask;
|
|
int threads_core
|
|
= (level == 2 ? threads_l2 : threads_l3);
|
|
|
|
/* Compute count mask. */
|
|
asm ("bsr %1, %0"
|
|
: "=r" (count_mask) : "g" (threads_core));
|
|
count_mask = ~(-1 << (count_mask + 1));
|
|
threads_core = (shipped - 1) & count_mask;
|
|
if (level == 2)
|
|
threads_l2 = threads_core;
|
|
else
|
|
threads_l3 = threads_core;
|
|
count &= ~(0x1 << 1);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if (threads_l2 > 0)
|
|
threads_l2 += 1;
|
|
if (threads_l3 > 0)
|
|
threads_l3 += 1;
|
|
if (level == 2)
|
|
{
|
|
if (threads_l2)
|
|
{
|
|
threads = threads_l2;
|
|
if (threads > 2 && family == 6)
|
|
switch (model)
|
|
{
|
|
case 0x37:
|
|
case 0x4a:
|
|
case 0x4d:
|
|
case 0x5a:
|
|
case 0x5d:
|
|
/* Silvermont has L2 cache shared by 2 cores. */
|
|
threads = 2;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
else if (threads_l3)
|
|
threads = threads_l3;
|
|
}
|
|
else
|
|
{
|
|
intel_bug_no_cache_info:
|
|
/* Assume that all logical threads share the highest cache
|
|
level. */
|
|
|
|
threads
|
|
= ((GLRO(dl_x86_cpu_features).cpuid[COMMON_CPUID_INDEX_1].ebx
|
|
>> 16) & 0xff);
|
|
}
|
|
|
|
/* Cap usage of highest cache level to the number of supported
|
|
threads. */
|
|
if (shared > 0 && threads > 0)
|
|
shared /= threads;
|
|
}
|
|
|
|
/* Account for non-inclusive L2 and L3 caches. */
|
|
if (!inclusive_cache)
|
|
{
|
|
if (threads_l2 > 0)
|
|
core /= threads_l2;
|
|
shared += core;
|
|
}
|
|
}
|
|
/* This spells out "AuthenticAMD". */
|
|
else if (is_amd)
|
|
{
|
|
data = handle_amd (_SC_LEVEL1_DCACHE_SIZE);
|
|
long int core = handle_amd (_SC_LEVEL2_CACHE_SIZE);
|
|
shared = handle_amd (_SC_LEVEL3_CACHE_SIZE);
|
|
|
|
/* Get maximum extended function. */
|
|
__cpuid (0x80000000, max_cpuid_ex, ebx, ecx, edx);
|
|
|
|
if (shared <= 0)
|
|
/* No shared L3 cache. All we have is the L2 cache. */
|
|
shared = core;
|
|
else
|
|
{
|
|
/* Figure out the number of logical threads that share L3. */
|
|
if (max_cpuid_ex >= 0x80000008)
|
|
{
|
|
/* Get width of APIC ID. */
|
|
__cpuid (0x80000008, max_cpuid_ex, ebx, ecx, edx);
|
|
threads = 1 << ((ecx >> 12) & 0x0f);
|
|
}
|
|
|
|
if (threads == 0)
|
|
{
|
|
/* If APIC ID width is not available, use logical
|
|
processor count. */
|
|
__cpuid (0x00000001, max_cpuid_ex, ebx, ecx, edx);
|
|
|
|
if ((edx & (1 << 28)) != 0)
|
|
threads = (ebx >> 16) & 0xff;
|
|
}
|
|
|
|
/* Cap usage of highest cache level to the number of
|
|
supported threads. */
|
|
if (threads > 0)
|
|
shared /= threads;
|
|
|
|
/* Account for exclusive L2 and L3 caches. */
|
|
shared += core;
|
|
}
|
|
|
|
#ifndef DISABLE_PREFETCHW
|
|
if (max_cpuid_ex >= 0x80000001)
|
|
{
|
|
__cpuid (0x80000001, eax, ebx, ecx, edx);
|
|
/* PREFETCHW || 3DNow! */
|
|
if ((ecx & 0x100) || (edx & 0x80000000))
|
|
__x86_prefetchw = -1;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
if (data > 0)
|
|
{
|
|
__x86_raw_data_cache_size_half = data / 2;
|
|
__x86_raw_data_cache_size = data;
|
|
/* Round data cache size to multiple of 256 bytes. */
|
|
data = data & ~255L;
|
|
__x86_data_cache_size_half = data / 2;
|
|
__x86_data_cache_size = data;
|
|
}
|
|
|
|
if (shared > 0)
|
|
{
|
|
__x86_raw_shared_cache_size_half = shared / 2;
|
|
__x86_raw_shared_cache_size = shared;
|
|
/* Round shared cache size to multiple of 256 bytes. */
|
|
shared = shared & ~255L;
|
|
__x86_shared_cache_size_half = shared / 2;
|
|
__x86_shared_cache_size = shared;
|
|
}
|
|
|
|
/* The large memcpy micro benchmark in glibc shows that 6 times of
|
|
shared cache size is the approximate value above which non-temporal
|
|
store becomes faster. */
|
|
__x86_shared_non_temporal_threshold = __x86_shared_cache_size * 6;
|
|
}
|