glibc/sysdeps/x86_64/cacheinfo.c
Ulrich Drepper 0435403c9d * sysdeps/x86_64/cacheinfo.c (__x86_64_data_cache_size_half): Renamed
from __x86_64_core_cache_size_half.
	(init_cacheinfo): Compute shared cache size for AMD processors with
	shared L3 correctly.
	* sysdeps/x86_64/memcpy.S: Adjust for __x86_64_data_cache_size_half
	name change.
	Patch in large parts by Evandro Menezes.
2007-09-22 05:54:03 +00:00

546 lines
14 KiB
C

/* x86_64 cache info.
Copyright (C) 2003, 2004, 2006, 2007 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
*/
#include <assert.h>
#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
static const struct intel_02_cache_info
{
unsigned int idx;
int name;
long int size;
long int assoc;
long int linesize;
} intel_02_known [] =
{
{ 0x06, _SC_LEVEL1_ICACHE_SIZE, 8192, 4, 32 },
{ 0x08, _SC_LEVEL1_ICACHE_SIZE, 16384, 4, 32 },
{ 0x0a, _SC_LEVEL1_DCACHE_SIZE, 8192, 2, 32 },
{ 0x0c, _SC_LEVEL1_DCACHE_SIZE, 16384, 4, 32 },
{ 0x22, _SC_LEVEL3_CACHE_SIZE, 524288, 4, 64 },
{ 0x23, _SC_LEVEL3_CACHE_SIZE, 1048576, 8, 64 },
{ 0x25, _SC_LEVEL3_CACHE_SIZE, 2097152, 8, 64 },
{ 0x29, _SC_LEVEL3_CACHE_SIZE, 4194304, 8, 64 },
{ 0x2c, _SC_LEVEL1_DCACHE_SIZE, 32768, 8, 64 },
{ 0x30, _SC_LEVEL1_ICACHE_SIZE, 32768, 8, 64 },
{ 0x39, _SC_LEVEL2_CACHE_SIZE, 131072, 4, 64 },
{ 0x3a, _SC_LEVEL2_CACHE_SIZE, 196608, 6, 64 },
{ 0x3b, _SC_LEVEL2_CACHE_SIZE, 131072, 2, 64 },
{ 0x3c, _SC_LEVEL2_CACHE_SIZE, 262144, 4, 64 },
{ 0x3d, _SC_LEVEL2_CACHE_SIZE, 393216, 6, 64 },
{ 0x3e, _SC_LEVEL2_CACHE_SIZE, 524288, 4, 64 },
{ 0x41, _SC_LEVEL2_CACHE_SIZE, 131072, 4, 32 },
{ 0x42, _SC_LEVEL2_CACHE_SIZE, 262144, 4, 32 },
{ 0x43, _SC_LEVEL2_CACHE_SIZE, 524288, 4, 32 },
{ 0x44, _SC_LEVEL2_CACHE_SIZE, 1048576, 4, 32 },
{ 0x45, _SC_LEVEL2_CACHE_SIZE, 2097152, 4, 32 },
{ 0x46, _SC_LEVEL3_CACHE_SIZE, 4194304, 4, 64 },
{ 0x47, _SC_LEVEL3_CACHE_SIZE, 8388608, 8, 64 },
{ 0x48, _SC_LEVEL2_CACHE_SIZE, 3145728, 12, 64 },
{ 0x49, _SC_LEVEL2_CACHE_SIZE, 4194304, 16, 64 },
{ 0x4a, _SC_LEVEL3_CACHE_SIZE, 6291456, 12, 64 },
{ 0x4b, _SC_LEVEL3_CACHE_SIZE, 8388608, 16, 64 },
{ 0x4c, _SC_LEVEL3_CACHE_SIZE, 12582912, 12, 64 },
{ 0x4d, _SC_LEVEL3_CACHE_SIZE, 16777216, 16, 64 },
{ 0x4e, _SC_LEVEL2_CACHE_SIZE, 6291456, 24, 64 },
{ 0x60, _SC_LEVEL1_DCACHE_SIZE, 16384, 8, 64 },
{ 0x66, _SC_LEVEL1_DCACHE_SIZE, 8192, 4, 64 },
{ 0x67, _SC_LEVEL1_DCACHE_SIZE, 16384, 4, 64 },
{ 0x68, _SC_LEVEL1_DCACHE_SIZE, 32768, 4, 64 },
{ 0x78, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 64 },
{ 0x79, _SC_LEVEL2_CACHE_SIZE, 131072, 8, 64 },
{ 0x7a, _SC_LEVEL2_CACHE_SIZE, 262144, 8, 64 },
{ 0x7b, _SC_LEVEL2_CACHE_SIZE, 524288, 8, 64 },
{ 0x7c, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 64 },
{ 0x7d, _SC_LEVEL2_CACHE_SIZE, 2097152, 8, 64 },
{ 0x7f, _SC_LEVEL2_CACHE_SIZE, 524288, 2, 64 },
{ 0x82, _SC_LEVEL2_CACHE_SIZE, 262144, 8, 32 },
{ 0x83, _SC_LEVEL2_CACHE_SIZE, 524288, 8, 32 },
{ 0x84, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 32 },
{ 0x85, _SC_LEVEL2_CACHE_SIZE, 2097152, 8, 32 },
{ 0x86, _SC_LEVEL2_CACHE_SIZE, 524288, 4, 64 },
{ 0x87, _SC_LEVEL2_CACHE_SIZE, 1048576, 8, 64 },
};
#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)
{
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_name = (_SC_LEVEL1_ICACHE_SIZE
+ ((name - _SC_LEVEL1_ICACHE_SIZE) / 3) * 3);
while (value != 0)
{
unsigned int byte = value & 0xff;
if (byte == 0x40)
{
*no_level_2_or_3 = true;
if (folded_name == _SC_LEVEL3_CACHE_SIZE)
/* No need to look further. */
break;
}
else
{
if (byte == 0x49 && folded_name == _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 eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (1));
unsigned int family = ((eax >> 20) & 0xff) + ((eax >> 8) & 0xf);
unsigned int model = ((((eax >>16) & 0xf) << 4)
+ ((eax >> 4) & 0xf));
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_name = _SC_LEVEL3_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->name == folded_name)
{
unsigned int offset = name - folded_name;
if (offset == 0)
/* Cache size. */
return found->size;
if (offset == 1)
return found->assoc;
assert (offset == 2);
return found->linesize;
}
if (found->name == _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, unsigned int maxidx)
{
assert (maxidx >= 2);
/* 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;
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (2));
/* 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);
if (result != 0)
return result;
result = intel_check_word (name, ebx, &has_level_2, &no_level_2_or_3);
if (result != 0)
return result;
result = intel_check_word (name, ecx, &has_level_2, &no_level_2_or_3);
if (result != 0)
return result;
result = intel_check_word (name, edx, &has_level_2, &no_level_2_or_3);
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;
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (0x80000000));
/* 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;
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (fn));
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)
{
/* Find out what brand of processor. */
unsigned int eax;
unsigned int ebx;
unsigned int ecx;
unsigned int edx;
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (0));
/* This spells out "GenuineIntel". */
if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69)
return handle_intel (name, eax);
/* This spells out "AuthenticAMD". */
if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
return handle_amd (name);
// XXX Fill in more vendors.
/* CPU not known, we have no information. */
return 0;
}
/* Half the data cache size for use in memory and string routines, typically
L1 size. */
long int __x86_64_data_cache_size_half attribute_hidden = 32 * 1024 / 2;
/* Shared cache size for use in memory and string routines, typically
L2 or L3 size. */
long int __x86_64_shared_cache_size_half attribute_hidden = 1024 * 1024 / 2;
/* PREFETCHW support flag for use in memory and string routines. */
int __x86_64_prefetchw attribute_hidden;
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;
int max_cpuid_ex;
long int data = -1;
long int shared = -1;
unsigned int level;
unsigned int threads = 0;
asm volatile ("cpuid"
: "=a" (max_cpuid), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (0));
/* This spells out "GenuineIntel". */
if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69)
{
data = handle_intel (_SC_LEVEL1_DCACHE_SIZE, max_cpuid);
/* Try L3 first. */
level = 3;
shared = handle_intel (_SC_LEVEL3_CACHE_SIZE, max_cpuid);
if (shared <= 0)
{
/* Try L2 otherwise. */
level = 2;
shared = handle_intel (_SC_LEVEL2_CACHE_SIZE, max_cpuid);
}
/* Figure out the number of logical threads that share the
highest cache level. */
if (max_cpuid >= 4)
{
int i = 0;
/* Query until desired cache level is enumerated. */
do
{
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (4), "2" (i++));
}
while (((eax >> 5) & 0x7) != level);
threads = ((eax >> 14) & 0x3ff) + 1;
}
else
{
/* Assume that all logical threads share the highest cache level. */
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (1));
threads = (ebx >> 16) & 0xff;
}
/* Cap usage of highest cache level to the number of supported
threads. */
if (shared > 0 && threads > 0)
shared /= threads;
}
/* This spells out "AuthenticAMD". */
else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65)
{
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. */
asm volatile ("cpuid"
: "=a" (max_cpuid_ex), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (0x80000000));
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. */
asm volatile ("cpuid"
: "=a" (max_cpuid_ex), "=b" (ebx), "=c" (ecx),
"=d" (edx)
: "0" (0x80000008));
threads = 1 << ((ecx >> 12) & 0x0f);
}
if (threads == 0)
{
/* If APIC ID width is not available, use logical
processor count. */
asm volatile ("cpuid"
: "=a" (max_cpuid_ex), "=b" (ebx), "=c" (ecx),
"=d" (edx)
: "0" (0x00000001));
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;
}
if (max_cpuid_ex >= 0x80000001)
{
asm volatile ("cpuid"
: "=a" (eax), "=b" (ebx), "=c" (ecx), "=d" (edx)
: "0" (0x80000001));
/* PREFETCHW || 3DNow! */
if ((ecx & 0x100) || (edx & 0x80000000))
__x86_64_prefetchw = -1;
}
}
if (data > 0)
__x86_64_data_cache_size_half = data / 2;
if (shared > 0)
__x86_64_shared_cache_size_half = shared / 2;
}