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Diffstat (limited to 'sysdeps/x86/cacheinfo.c')
-rw-r--r--sysdeps/x86/cacheinfo.c791
1 files changed, 791 insertions, 0 deletions
diff --git a/sysdeps/x86/cacheinfo.c b/sysdeps/x86/cacheinfo.c
new file mode 100644
index 0000000000..b9444ddd52
--- /dev/null
+++ b/sysdeps/x86/cacheinfo.c
@@ -0,0 +1,791 @@
+/* x86_64 cache info.
+ Copyright (C) 2003-2018 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 (cpu_features->data_cache_size != 0)
+ data = cpu_features->data_cache_size;
+
+ 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 (cpu_features->shared_cache_size != 0)
+ shared = cpu_features->shared_cache_size;
+
+ 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
+ = (cpu_features->non_temporal_threshold != 0
+ ? cpu_features->non_temporal_threshold
+ : __x86_shared_cache_size * threads * 3 / 4);
+}
+
+#endif
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-30 09:52:30 +0000