diff options
Diffstat (limited to 'REORG.TODO/sysdeps/x86/cacheinfo.c')
| -rw-r--r-- | REORG.TODO/sysdeps/x86/cacheinfo.c | 783 |
1 files changed, 783 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/x86/cacheinfo.c b/REORG.TODO/sysdeps/x86/cacheinfo.c new file mode 100644 index 0000000000..8000fd1e99 --- /dev/null +++ b/REORG.TODO/sysdeps/x86/cacheinfo.c @@ -0,0 +1,783 @@ +/* x86_64 cache info. + Copyright (C) 2003-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#if IS_IN (libc) + +#include <assert.h> +#include <stdbool.h> +#include <stdlib.h> +#include <unistd.h> +#include <cpuid.h> +#include <init-arch.h> + +static const struct intel_02_cache_info +{ + unsigned char idx; + unsigned char assoc; + unsigned char linesize; + unsigned char rel_name; + unsigned int size; +} intel_02_known [] = + { +#define M(sc) ((sc) - _SC_LEVEL1_ICACHE_SIZE) + { 0x06, 4, 32, M(_SC_LEVEL1_ICACHE_SIZE), 8192 }, + { 0x08, 4, 32, M(_SC_LEVEL1_ICACHE_SIZE), 16384 }, + { 0x09, 4, 32, M(_SC_LEVEL1_ICACHE_SIZE), 32768 }, + { 0x0a, 2, 32, M(_SC_LEVEL1_DCACHE_SIZE), 8192 }, + { 0x0c, 4, 32, M(_SC_LEVEL1_DCACHE_SIZE), 16384 }, + { 0x0d, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 16384 }, + { 0x0e, 6, 64, M(_SC_LEVEL1_DCACHE_SIZE), 24576 }, + { 0x21, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 }, + { 0x22, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 524288 }, + { 0x23, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 1048576 }, + { 0x25, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 }, + { 0x29, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 }, + { 0x2c, 8, 64, M(_SC_LEVEL1_DCACHE_SIZE), 32768 }, + { 0x30, 8, 64, M(_SC_LEVEL1_ICACHE_SIZE), 32768 }, + { 0x39, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 131072 }, + { 0x3a, 6, 64, M(_SC_LEVEL2_CACHE_SIZE), 196608 }, + { 0x3b, 2, 64, M(_SC_LEVEL2_CACHE_SIZE), 131072 }, + { 0x3c, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 }, + { 0x3d, 6, 64, M(_SC_LEVEL2_CACHE_SIZE), 393216 }, + { 0x3e, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x3f, 2, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 }, + { 0x41, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 131072 }, + { 0x42, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 262144 }, + { 0x43, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x44, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 1048576 }, + { 0x45, 4, 32, M(_SC_LEVEL2_CACHE_SIZE), 2097152 }, + { 0x46, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 }, + { 0x47, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 }, + { 0x48, 12, 64, M(_SC_LEVEL2_CACHE_SIZE), 3145728 }, + { 0x49, 16, 64, M(_SC_LEVEL2_CACHE_SIZE), 4194304 }, + { 0x4a, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 6291456 }, + { 0x4b, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 }, + { 0x4c, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 12582912 }, + { 0x4d, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 16777216 }, + { 0x4e, 24, 64, M(_SC_LEVEL2_CACHE_SIZE), 6291456 }, + { 0x60, 8, 64, M(_SC_LEVEL1_DCACHE_SIZE), 16384 }, + { 0x66, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 8192 }, + { 0x67, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 16384 }, + { 0x68, 4, 64, M(_SC_LEVEL1_DCACHE_SIZE), 32768 }, + { 0x78, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 1048576 }, + { 0x79, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 131072 }, + { 0x7a, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 262144 }, + { 0x7b, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x7c, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 1048576 }, + { 0x7d, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 2097152 }, + { 0x7f, 2, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x80, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x82, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 262144 }, + { 0x83, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x84, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 1048576 }, + { 0x85, 8, 32, M(_SC_LEVEL2_CACHE_SIZE), 2097152 }, + { 0x86, 4, 64, M(_SC_LEVEL2_CACHE_SIZE), 524288 }, + { 0x87, 8, 64, M(_SC_LEVEL2_CACHE_SIZE), 1048576 }, + { 0xd0, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 524288 }, + { 0xd1, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 1048576 }, + { 0xd2, 4, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 }, + { 0xd6, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 1048576 }, + { 0xd7, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 }, + { 0xd8, 8, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 }, + { 0xdc, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 }, + { 0xdd, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 }, + { 0xde, 12, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 }, + { 0xe2, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 2097152 }, + { 0xe3, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 4194304 }, + { 0xe4, 16, 64, M(_SC_LEVEL3_CACHE_SIZE), 8388608 }, + { 0xea, 24, 64, M(_SC_LEVEL3_CACHE_SIZE), 12582912 }, + { 0xeb, 24, 64, M(_SC_LEVEL3_CACHE_SIZE), 18874368 }, + { 0xec, 24, 64, M(_SC_LEVEL3_CACHE_SIZE), 25165824 }, + }; + +#define nintel_02_known (sizeof (intel_02_known) / sizeof (intel_02_known [0])) + +static int +intel_02_known_compare (const void *p1, const void *p2) +{ + const struct intel_02_cache_info *i1; + const struct intel_02_cache_info *i2; + + i1 = (const struct intel_02_cache_info *) p1; + i2 = (const struct intel_02_cache_info *) p2; + + if (i1->idx == i2->idx) + return 0; + + return i1->idx < i2->idx ? -1 : 1; +} + + +static long int +__attribute__ ((noinline)) +intel_check_word (int name, unsigned int value, bool *has_level_2, + bool *no_level_2_or_3, + const struct cpu_features *cpu_features) +{ + if ((value & 0x80000000) != 0) + /* The register value is reserved. */ + return 0; + + /* Fold the name. The _SC_ constants are always in the order SIZE, + ASSOC, LINESIZE. */ + int folded_rel_name = (M(name) / 3) * 3; + + while (value != 0) + { + unsigned int byte = value & 0xff; + + if (byte == 0x40) + { + *no_level_2_or_3 = true; + + if (folded_rel_name == M(_SC_LEVEL3_CACHE_SIZE)) + /* No need to look further. */ + break; + } + else if (byte == 0xff) + { + /* CPUID leaf 0x4 contains all the information. We need to + iterate over it. */ + unsigned int eax; + unsigned int ebx; + unsigned int ecx; + unsigned int edx; + + unsigned int round = 0; + while (1) + { + __cpuid_count (4, round, eax, ebx, ecx, edx); + + enum { null = 0, data = 1, inst = 2, uni = 3 } type = eax & 0x1f; + if (type == null) + /* That was the end. */ + break; + + unsigned int level = (eax >> 5) & 0x7; + + if ((level == 1 && type == data + && folded_rel_name == M(_SC_LEVEL1_DCACHE_SIZE)) + || (level == 1 && type == inst + && folded_rel_name == M(_SC_LEVEL1_ICACHE_SIZE)) + || (level == 2 && folded_rel_name == M(_SC_LEVEL2_CACHE_SIZE)) + || (level == 3 && folded_rel_name == M(_SC_LEVEL3_CACHE_SIZE)) + || (level == 4 && folded_rel_name == M(_SC_LEVEL4_CACHE_SIZE))) + { + unsigned int offset = M(name) - folded_rel_name; + + if (offset == 0) + /* Cache size. */ + return (((ebx >> 22) + 1) + * (((ebx >> 12) & 0x3ff) + 1) + * ((ebx & 0xfff) + 1) + * (ecx + 1)); + if (offset == 1) + return (ebx >> 22) + 1; + + assert (offset == 2); + return (ebx & 0xfff) + 1; + } + + ++round; + } + /* There is no other cache information anywhere else. */ + break; + } + else + { + if (byte == 0x49 && folded_rel_name == M(_SC_LEVEL3_CACHE_SIZE)) + { + /* Intel reused this value. For family 15, model 6 it + specifies the 3rd level cache. Otherwise the 2nd + level cache. */ + unsigned int family = cpu_features->family; + unsigned int model = cpu_features->model; + + if (family == 15 && model == 6) + { + /* The level 3 cache is encoded for this model like + the level 2 cache is for other models. Pretend + the caller asked for the level 2 cache. */ + name = (_SC_LEVEL2_CACHE_SIZE + + (name - _SC_LEVEL3_CACHE_SIZE)); + folded_rel_name = M(_SC_LEVEL2_CACHE_SIZE); + } + } + + struct intel_02_cache_info *found; + struct intel_02_cache_info search; + + search.idx = byte; + found = bsearch (&search, intel_02_known, nintel_02_known, + sizeof (intel_02_known[0]), intel_02_known_compare); + if (found != NULL) + { + if (found->rel_name == folded_rel_name) + { + unsigned int offset = M(name) - folded_rel_name; + + if (offset == 0) + /* Cache size. */ + return found->size; + if (offset == 1) + return found->assoc; + + assert (offset == 2); + return found->linesize; + } + + if (found->rel_name == M(_SC_LEVEL2_CACHE_SIZE)) + *has_level_2 = true; + } + } + + /* Next byte for the next round. */ + value >>= 8; + } + + /* Nothing found. */ + return 0; +} + + +static long int __attribute__ ((noinline)) +handle_intel (int name, const struct cpu_features *cpu_features) +{ + unsigned int maxidx = cpu_features->max_cpuid; + + /* Return -1 for older CPUs. */ + if (maxidx < 2) + return -1; + + /* OK, we can use the CPUID instruction to get all info about the + caches. */ + unsigned int cnt = 0; + unsigned int max = 1; + long int result = 0; + bool no_level_2_or_3 = false; + bool has_level_2 = false; + + while (cnt++ < max) + { + unsigned int eax; + unsigned int ebx; + unsigned int ecx; + unsigned int edx; + __cpuid (2, eax, ebx, ecx, edx); + + /* The low byte of EAX in the first round contain the number of + rounds we have to make. At least one, the one we are already + doing. */ + if (cnt == 1) + { + max = eax & 0xff; + eax &= 0xffffff00; + } + + /* Process the individual registers' value. */ + result = intel_check_word (name, eax, &has_level_2, + &no_level_2_or_3, cpu_features); + if (result != 0) + return result; + + result = intel_check_word (name, ebx, &has_level_2, + &no_level_2_or_3, cpu_features); + if (result != 0) + return result; + + result = intel_check_word (name, ecx, &has_level_2, + &no_level_2_or_3, cpu_features); + if (result != 0) + return result; + + result = intel_check_word (name, edx, &has_level_2, + &no_level_2_or_3, cpu_features); + if (result != 0) + return result; + } + + if (name >= _SC_LEVEL2_CACHE_SIZE && name <= _SC_LEVEL3_CACHE_LINESIZE + && no_level_2_or_3) + return -1; + + return 0; +} + + +static long int __attribute__ ((noinline)) +handle_amd (int name) +{ + unsigned int eax; + unsigned int ebx; + unsigned int ecx; + unsigned int edx; + __cpuid (0x80000000, eax, ebx, ecx, edx); + + /* No level 4 cache (yet). */ + if (name > _SC_LEVEL3_CACHE_LINESIZE) + return 0; + + unsigned int fn = 0x80000005 + (name >= _SC_LEVEL2_CACHE_SIZE); + if (eax < fn) + return 0; + + __cpuid (fn, eax, ebx, ecx, edx); + + if (name < _SC_LEVEL1_DCACHE_SIZE) + { + name += _SC_LEVEL1_DCACHE_SIZE - _SC_LEVEL1_ICACHE_SIZE; + ecx = edx; + } + + switch (name) + { + case _SC_LEVEL1_DCACHE_SIZE: + return (ecx >> 14) & 0x3fc00; + + case _SC_LEVEL1_DCACHE_ASSOC: + ecx >>= 16; + if ((ecx & 0xff) == 0xff) + /* Fully associative. */ + return (ecx << 2) & 0x3fc00; + return ecx & 0xff; + + case _SC_LEVEL1_DCACHE_LINESIZE: + return ecx & 0xff; + + case _SC_LEVEL2_CACHE_SIZE: + return (ecx & 0xf000) == 0 ? 0 : (ecx >> 6) & 0x3fffc00; + + case _SC_LEVEL2_CACHE_ASSOC: + switch ((ecx >> 12) & 0xf) + { + case 0: + case 1: + case 2: + case 4: + return (ecx >> 12) & 0xf; + case 6: + return 8; + case 8: + return 16; + case 10: + return 32; + case 11: + return 48; + case 12: + return 64; + case 13: + return 96; + case 14: + return 128; + case 15: + return ((ecx >> 6) & 0x3fffc00) / (ecx & 0xff); + default: + return 0; + } + /* NOTREACHED */ + + case _SC_LEVEL2_CACHE_LINESIZE: + return (ecx & 0xf000) == 0 ? 0 : ecx & 0xff; + + case _SC_LEVEL3_CACHE_SIZE: + return (edx & 0xf000) == 0 ? 0 : (edx & 0x3ffc0000) << 1; + + case _SC_LEVEL3_CACHE_ASSOC: + switch ((edx >> 12) & 0xf) + { + case 0: + case 1: + case 2: + case 4: + return (edx >> 12) & 0xf; + case 6: + return 8; + case 8: + return 16; + case 10: + return 32; + case 11: + return 48; + case 12: + return 64; + case 13: + return 96; + case 14: + return 128; + case 15: + return ((edx & 0x3ffc0000) << 1) / (edx & 0xff); + default: + return 0; + } + /* NOTREACHED */ + + case _SC_LEVEL3_CACHE_LINESIZE: + return (edx & 0xf000) == 0 ? 0 : edx & 0xff; + + default: + assert (! "cannot happen"); + } + return -1; +} + + +/* Get the value of the system variable NAME. */ +long int +attribute_hidden +__cache_sysconf (int name) +{ + const struct cpu_features *cpu_features = __get_cpu_features (); + + if (cpu_features->kind == arch_kind_intel) + return handle_intel (name, cpu_features); + + if (cpu_features->kind == arch_kind_amd) + return handle_amd (name); + + // XXX Fill in more vendors. + + /* CPU not known, we have no information. */ + return 0; +} + + +/* Data cache size for use in memory and string routines, typically + L1 size, rounded to multiple of 256 bytes. */ +long int __x86_data_cache_size_half attribute_hidden = 32 * 1024 / 2; +long int __x86_data_cache_size attribute_hidden = 32 * 1024; +/* Similar to __x86_data_cache_size_half, but not rounded. */ +long int __x86_raw_data_cache_size_half attribute_hidden = 32 * 1024 / 2; +/* Similar to __x86_data_cache_size, but not rounded. */ +long int __x86_raw_data_cache_size attribute_hidden = 32 * 1024; +/* Shared cache size for use in memory and string routines, typically + 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; + const struct cpu_features *cpu_features = __get_cpu_features (); + int max_cpuid = cpu_features->max_cpuid; + + if (cpu_features->kind == arch_kind_intel) + { + data = handle_intel (_SC_LEVEL1_DCACHE_SIZE, cpu_features); + + long int core = handle_intel (_SC_LEVEL2_CACHE_SIZE, cpu_features); + bool inclusive_cache = true; + + /* Try L3 first. */ + level = 3; + shared = handle_intel (_SC_LEVEL3_CACHE_SIZE, cpu_features); + + /* 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 = cpu_features->family; + unsigned int model = 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 + = ((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; + } + } + else if (cpu_features->kind == arch_kind_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 on a 8-core processor. This is the 3/4 of the + total shared cache size. */ + __x86_shared_non_temporal_threshold + = __x86_shared_cache_size * threads * 3 / 4; +} + +#endif |