glibc/sysdeps/unix/sysv/linux/s390/sysconf.c

231 lines
6.0 KiB
C

/* Get system parameters, e.g. cache information. S390/S390x version.
Copyright (C) 2015-2016 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/>. */
#include <unistd.h>
#include <dl-procinfo.h>
static long int linux_sysconf (int name);
/* Possible arguments for get_cache_info.
The values are reflecting the level/attribute/type indications
of ecag-instruction (extract cpu attribue). */
#define CACHE_LEVEL_MAX 8
#define CACHE_ATTR_LINESIZE 1
#define CACHE_ATTR_SIZE 2
#define CACHE_ATTR_ASSOC 3
#define CACHE_TYPE_DATA 0
#define CACHE_TYPE_INSTRUCTION 1
static long
get_cache_info (int level, int attr, int type)
{
unsigned long int val;
unsigned int cmd;
unsigned long int arg;
/* Check arguments. */
if (level < 1 || level > CACHE_LEVEL_MAX
|| attr < CACHE_ATTR_LINESIZE || attr > CACHE_ATTR_ASSOC
|| type < CACHE_TYPE_DATA || type > CACHE_TYPE_INSTRUCTION)
return 0L;
/* Check if ecag-instruction is available.
ecag - extract CPU attribute (only in zarch; arch >= z10; in as 2.24) */
if (!(GLRO (dl_hwcap) & HWCAP_S390_STFLE)
#if !defined __s390x__
|| !(GLRO (dl_hwcap) & HWCAP_S390_ZARCH)
|| !(GLRO (dl_hwcap) & HWCAP_S390_HIGH_GPRS)
#endif /* !__s390x__ */
)
{
/* stfle (or zarch, high-gprs on s390-32) is not available.
We are on an old machine. Return 256byte for LINESIZE for L1 d/i-cache,
otherwise 0. */
if (level == 1 && attr == CACHE_ATTR_LINESIZE)
return 256L;
else
return 0L;
}
/* Store facility list and check for z10.
(see ifunc-resolver for details) */
register unsigned long reg0 __asm__("0") = 0;
#ifdef __s390x__
unsigned long stfle_bits;
# define STFLE_Z10_MASK (1UL << (63 - 34))
#else
unsigned long long stfle_bits;
# define STFLE_Z10_MASK (1ULL << (63 - 34))
#endif /* !__s390x__ */
__asm__ __volatile__(".machine push" "\n\t"
".machinemode \"zarch_nohighgprs\"\n\t"
".machine \"z9-109\"" "\n\t"
"stfle %0" "\n\t"
".machine pop" "\n"
: "=QS" (stfle_bits), "+d" (reg0)
: : "cc");
if (!(stfle_bits & STFLE_Z10_MASK))
{
/* We are at least on a z9 machine.
Return 256byte for LINESIZE for L1 d/i-cache,
otherwise 0. */
if (level == 1 && attr == CACHE_ATTR_LINESIZE)
return 256L;
else
return 0L;
}
/* Check cache topology, if cache is available at this level. */
arg = (CACHE_LEVEL_MAX - level) * 8;
__asm__ __volatile__ (".machine push\n\t"
".machine \"z10\"\n\t"
".machinemode \"zarch_nohighgprs\"\n\t"
"ecag %0,%%r0,0\n\t" /* returns 64bit unsigned integer. */
"srlg %0,%0,0(%1)\n\t" /* right align 8bit cache info field. */
".machine pop"
: "=&d" (val)
: "a" (arg)
);
val &= 0xCUL; /* Extract cache scope information from cache topology summary.
(bits 4-5 of 8bit-field; 00 means cache does not exist). */
if (val == 0)
return 0L;
/* Get cache information for level, attribute and type. */
cmd = (attr << 4) | ((level - 1) << 1) | type;
__asm__ __volatile__ (".machine push\n\t"
".machine \"z10\"\n\t"
".machinemode \"zarch_nohighgprs\"\n\t"
"ecag %0,%%r0,0(%1)\n\t"
".machine pop"
: "=d" (val)
: "a" (cmd)
);
return val;
}
long int
__sysconf (int name)
{
if (name >= _SC_LEVEL1_ICACHE_SIZE && name <= _SC_LEVEL4_CACHE_LINESIZE)
{
int level;
int attr;
int type;
switch (name)
{
case _SC_LEVEL1_ICACHE_SIZE:
level = 1;
attr = CACHE_ATTR_SIZE;
type = CACHE_TYPE_INSTRUCTION;
break;
case _SC_LEVEL1_ICACHE_ASSOC:
level = 1;
attr = CACHE_ATTR_ASSOC;
type = CACHE_TYPE_INSTRUCTION;
break;
case _SC_LEVEL1_ICACHE_LINESIZE:
level = 1;
attr = CACHE_ATTR_LINESIZE;
type = CACHE_TYPE_INSTRUCTION;
break;
case _SC_LEVEL1_DCACHE_SIZE:
level = 1;
attr = CACHE_ATTR_SIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL1_DCACHE_ASSOC:
level = 1;
attr = CACHE_ATTR_ASSOC;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL1_DCACHE_LINESIZE:
level = 1;
attr = CACHE_ATTR_LINESIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL2_CACHE_SIZE:
level = 2;
attr = CACHE_ATTR_SIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL2_CACHE_ASSOC:
level = 2;
attr = CACHE_ATTR_ASSOC;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL2_CACHE_LINESIZE:
level = 2;
attr = CACHE_ATTR_LINESIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL3_CACHE_SIZE:
level = 3;
attr = CACHE_ATTR_SIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL3_CACHE_ASSOC:
level = 3;
attr = CACHE_ATTR_ASSOC;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL3_CACHE_LINESIZE:
level = 3;
attr = CACHE_ATTR_LINESIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL4_CACHE_SIZE:
level = 4;
attr = CACHE_ATTR_SIZE;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL4_CACHE_ASSOC:
level = 4;
attr = CACHE_ATTR_ASSOC;
type = CACHE_TYPE_DATA;
break;
case _SC_LEVEL4_CACHE_LINESIZE:
level = 4;
attr = CACHE_ATTR_LINESIZE;
type = CACHE_TYPE_DATA;
break;
default:
level = 0;
attr = 0;
type = 0;
break;
}
return get_cache_info (level, attr, type);
}
return linux_sysconf (name);
}
/* Now the generic Linux version. */
#undef __sysconf
#define __sysconf static linux_sysconf
#include <sysdeps/unix/sysv/linux/sysconf.c>