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38 .Nd access per-CPU data
47 .Fn kvm_dpcpu_setcpu "kvm_t *kd" "u_int cpu"
49 .Fn kvm_getmaxcpu "kvm_t *kd"
51 .Fn kvm_getpcpu "kvm_t *kd" "int cpu"
54 .Fn kvm_dpcpu_setcpu ,
58 functions are used to access the per-CPU data of active processors in the
61 Per-CPU storage comes in two flavours: data stored directly in a
63 associated with each CPU, and dynamic per-CPU storage (DPCPU), in which a
64 single kernel symbol refers to different data depending on what CPU it is
69 function returns the maximum number of CPUs supported by the kernel.
73 function returns a buffer holding the per-CPU data for a single CPU.
74 This buffer is described by the
77 The caller is responsible for releasing the buffer via a call to
79 when it is no longer needed.
86 Symbols for dynamic per-CPU data are accessed via
88 as with other symbols.
90 maintains a notion of the "current CPU", set by
91 .Xr kvm_dpcpu_setcpu ,
93 Once another CPU is selected,
95 will return pointers to that data on the appropriate CPU.
100 cache the nlist values for various kernel variables which are
101 reused in successive calls.
102 You may call either function with
110 function returns the maximum number of CPUs supported by the kernel.
112 it returns -1 instead.
116 function returns a pointer to an allocated buffer or
119 it returns -1 instead.
123 call returns 0; if an error occurs, it returns -1 instead.
125 If any function encounters an error,
126 then an error message may be retrieved via