42 lines
		
	
	
		
			949 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			42 lines
		
	
	
		
			949 B
		
	
	
	
		
			C
		
	
	
	
	
	
| #include <cstdio>
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| 
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| static inline int getPossibleCPUs()
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| {
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|    FILE* cpuPossible = fopen("/sys/devices/system/cpu/possible", "r");
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|    if(!cpuPossible)
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|        return 1;
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| 
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|    char buf[2000]; //big enough for 1000 CPUs in worst possible configuration
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|    char* pbuf = fgets(buf, sizeof(buf), cpuPossible);
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|    fclose(cpuPossible);
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|    if(!pbuf)
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|       return 1;
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| 
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|    //parse string of form "0-1,3,5-7,10,13-15"
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|    int cpusAvailable = 0;
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| 
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|    while(*pbuf)
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|    {
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|       const char* pos = pbuf;
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|       bool range = false;
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|       while(*pbuf && *pbuf != ',')
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|       {
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|           if(*pbuf == '-') range = true;
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|           ++pbuf;
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|       }
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|       if(*pbuf) *pbuf++ = 0;
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|       if(!range)
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|         ++cpusAvailable;
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|       else
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|       {
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|           int rstart = 0, rend = 0;
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|           sscanf(pos, "%d-%d", &rstart, &rend);
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|           cpusAvailable += rend - rstart + 1;
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|       }
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| 
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|    }
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|    return cpusAvailable ? cpusAvailable : 1;
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| }
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| 
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| #define __TBB_HardwareConcurrency() getPossibleCPUs()
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