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Revert HT detection 

Fall back on 1.6.3 behaviour.

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
sf_2.3.1_base
Marco Costalba 2010-04-10 11:35:30 +01:00
parent e2880f9b8e
commit d720778b2b
1 changed files with 9 additions and 55 deletions
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64
src/misc.cpp
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@ -41,13 +41,13 @@
#include <cassert>
#include <cstdio>
#include <cstring>
#include <iomanip>
#include <iostream>
#include <sstream>
#include "bitcount.h"
#include "misc.h"
#include "thread.h"
using namespace std;
@ -183,85 +183,39 @@ int get_system_time() {
}
/// builtin_cpu_count() tries to detect the number of CPU cores, if
/// hyper-threading is enabled this is the number of logical processors.
/// cpu_count() tries to detect the number of CPU cores.
#if !defined(_MSC_VER)
# if defined(_SC_NPROCESSORS_ONLN)
static int builtin_cpu_count() {
return Min(sysconf(_SC_NPROCESSORS_ONLN), 8);
int cpu_count() {
return Min(sysconf(_SC_NPROCESSORS_ONLN), MAX_THREADS);
}
# elif defined(__hpux)
static int builtin_cpu_count() {
int cpu_count() {
struct pst_dynamic psd;
if (pstat_getdynamic(&psd, sizeof(psd), (size_t)1, 0) == -1)
return 1;
return Min(psd.psd_proc_cnt, 8);
return Min(psd.psd_proc_cnt, MAX_THREADS);
}
# else
static int builtin_cpu_count() {
int cpu_count() {
return 1;
}
# endif
#else
static int builtin_cpu_count() {
int cpu_count() {
SYSTEM_INFO s;
GetSystemInfo(&s);
return Min(s.dwNumberOfProcessors, 8);
return Min(s.dwNumberOfProcessors, MAX_THREADS);
}
#endif
/// HT_enabled() returns true if hyper-threading is enabled on current machine
static bool HT_enabled() {
char CPUString[0x20];
int CPUInfo[4] = {-1};
int nIds, nLogicalCPU, nCores;
// Detect CPU producer
__cpuid(CPUInfo, 0);
nIds = CPUInfo[0];
memset(CPUString, 0, sizeof(CPUString));
memcpy(&CPUString[0], &CPUInfo[1], sizeof(int));
memcpy(&CPUString[4], &CPUInfo[3], sizeof(int));
memcpy(&CPUString[8], &CPUInfo[2], sizeof(int));
// Not an Intel CPU or CPUID.4 not supported
if (strcmp(CPUString, "GenuineIntel") || nIds < 4)
return false;
// Detect if HT Technology is supported
__cpuid(CPUInfo, 1);
if (!((CPUInfo[3] >> 28) & 1))
return false;
nLogicalCPU = (CPUInfo[1] >> 16) & 0xFF;
// Detect number of cores
__cpuid(CPUInfo, 4);
nCores = 1 + ((CPUInfo[0] >> 26) & 0x3F);
return nLogicalCPU > nCores;
}
/// cpu_count() tries to detect the number of physical CPU cores taking
/// in account hyper-threading.
int cpu_count() {
return HT_enabled() ? builtin_cpu_count() / 2 : builtin_cpu_count();
}
/*
From Beowulf, from Olithink
*/