cds/os/free_bsd/topology.h

   1 //$$CDS-header$$
   2
   3 #ifndef __CDS_OS_FREE_BSD_TOPOLOGY_H
   4 #define __CDS_OS_FREE_BSD_TOPOLOGY_H
   5
   6 #ifndef __CDS_OS_TOPOLOGY_H
   7 #   error "<cds/os/topology.h> must be included instead"
   8 #endif
   9
  10 #include <cds/os/details/fake_topology.h>
  11
  12 #include <sys/types.h>
  13 #include <sys/sysctl.h>
  14
  15 namespace cds { namespace OS {
  16
  17     /// FreeBSD-specific wrappers
  18     CDS_CXX11_INLINE_NAMESPACE namespace Free_BSD {
  19
  20         /// System topology
  21         /**
  22             The implementation assumes that processor IDs are in numerical order
  23             from 0 to N - 1, where N - count of processor in the system
  24         */
  25         struct topology: public OS::details::fake_topology
  26         {
  27         private:
  28             //@cond
  29             typedef OS::details::fake_topology  base_class;
  30             //@endcond
  31         public:
  32
  33             /// Logical processor count for the system
  34             static unsigned int processor_count()
  35             {
  36                 int mib[4];
  37
  38                 /* set the mib for hw.ncpu */
  39                 mib[0] = CTL_HW;
  40                 mib[1] = HW_NCPU;
  41                 int nCPU = 0;
  42                 size_t len = sizeof(nCPU);
  43
  44                 /* get the number of CPUs from the system */
  45                 return ::sysctl(mib, 2, &nCPU, &len, NULL, 0) == 0 && nCPU > 0 ? (unsigned int) nCPU : 1;
  46             }
  47
  48             /// Get current processor number
  49             /**
  50                 Caveat: FreeBSD has no "get current processor number" system call.
  51                 The function emulates "current processor number" using thread-specific data.
  52             */
  53             static unsigned int current_processor()
  54             {
  55                 return base_class::current_processor();
  56             }
  57
  58             /// Synonym for \ref current_processor
  59             static unsigned int native_current_processor()
  60             {
  61                 return current_processor();
  62             }
  63
  64             //@cond
  65             static void init()
  66             {}
  67             static void fini()
  68             {}
  69             //@endcond
  70         };
  71     }   // namespace Free_BSD
  72
  73 #ifndef CDS_CXX11_INLINE_NAMESPACE_SUPPORT
  74     using Free_BSD::topology;
  75 #endif
  76 }}  // namespace cds::OS
  77
  78 #endif  // #ifndef __CDS_OS_FREE_BSD_TOPOLOGY_H