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-rw-r--r--sysdeps/unix/sysv/linux/i386/sysconf.c9
-rw-r--r--sysdeps/unix/sysv/linux/x86_64/sysconf.c238
2 files changed, 246 insertions, 1 deletions
diff --git a/sysdeps/unix/sysv/linux/i386/sysconf.c b/sysdeps/unix/sysv/linux/i386/sysconf.c
index 067c752924..54e78409d4 100644
--- a/sysdeps/unix/sysv/linux/i386/sysconf.c
+++ b/sysdeps/unix/sysv/linux/i386/sysconf.c
@@ -143,7 +143,13 @@ intel_check_word (int name, unsigned int value, bool *has_level_2,
       unsigned int byte = value & 0xff;
 
       if (byte == 0x40)
-	*no_level_2_or_3 = true;
+	{
+	  *no_level_2_or_3 = true;
+
+	  if (folded_name == _SC_LEVEL3_CACHE_SIZE)
+	    /* No need to look further.  */
+	    break;
+	}
       else
 	{
 	  struct intel_02_cache_info *found;
@@ -290,6 +296,7 @@ __sysconf (int name)
 		: "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx)
 		: "0" (0));
 
+  /* This spells out "GenuineIntel".  */
   if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69)
     return handle_intel (name, eax);
   // XXX Fill in more vendors.
diff --git a/sysdeps/unix/sysv/linux/x86_64/sysconf.c b/sysdeps/unix/sysv/linux/x86_64/sysconf.c
new file mode 100644
index 0000000000..ab777ba0cd
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/sysconf.c
@@ -0,0 +1,238 @@
+/* Get file-specific information about a file.  Linux version.
+   Copyright (C) 2003, 2004 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 long int linux_sysconf (int name);
+
+
+static 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 },
+    { 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 },
+    { 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 },
+    { 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
+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
+	{
+	  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
+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 ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1"
+		    : "=a" (eax), "=r" (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;
+}
+
+
+/* Get the value of the system variable NAME.  */
+long int
+__sysconf (int name)
+{
+  /* We only handle the cache information here (for now).  */
+  if (name < _SC_LEVEL1_ICACHE_SIZE || name > _SC_LEVEL4_CACHE_ASSOC)
+    return linux_sysconf (name);
+
+  /* Find out what brand of processor.  */
+  unsigned int eax;
+  unsigned int ebx;
+  unsigned int ecx;
+  unsigned int edx;
+  asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1"
+		: "=a" (eax), "=r" (ebx), "=c" (ecx), "=d" (edx)
+		: "0" (0));
+
+  /* This spells out "GenuineIntel".  */
+  if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69)
+    return handle_intel (name, eax);
+  // XXX Fill in more vendors.
+
+  /* CPU not known, we have no information.  */
+  return 0;
+}
+
+/* Now the generic Linux version.  */
+#undef __sysconf
+#define __sysconf static linux_sysconf
+#include "../sysconf.c"