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.Dd July 8, 2023 .Dt CURPROC 9 .Os .Sh NAME .Nm curcpu , .Nm curlwp , .Nm curproc .Nd current processor, thread, and process .Sh SYNOPSIS n sys/proc.h .Ft struct cpu_info * .Fn curcpu "void" .Vt struct proc *curproc ; .Vt struct lwp *curlwp ; n sys/cpu.h .Ft bool .Fn curcpu_stable "void" .Sh DESCRIPTION The following retrieve the current CPU, process, and thread
q lightweight process, or Tn LWP , respectively: l -tag -width Dv t Fn curcpu Returns a pointer to the .Vt "struct cpu_info" structure representing the CPU that the code calling it is running on.
p The value of .Fn curcpu is unstable and may be stale as soon as it is read unless the caller prevents preemption by raising the IPL
q Xr spl 9 , Xr mutex 9 , by disabling preemption
q Xr kpreempt_disable 9 , or by binding the thread to its CPU
q Xr curlwp_bind 9 .
p The function .Fn curcpu_stable can be used in assertions
q Xr KASSERT 9 to verify that .Fn curcpu is stable in the current context. .Fn curcpu_stable MUST NOT be used to make dynamic decisions about whether to query .Fn curcpu . t Dv curproc Yields a pointer to the .Vt "struct proc" structure representing the currently running process.
p The value of .Dv curproc is stable and does not change during execution except in machine-dependent logic to perform context switches, so it works like a global constant, not like a stateful procedure. t Dv curlwp Yields a pointer to the .Vt "struct lwp" structure representing the currently running thread.
p The value of .Dv curlwp is stable and does not change during execution except in machine-dependent logic to perform context switches, so it works like a global constant, not like a stateful procedure. .El .Sh SOURCE REFERENCES The .Fn curcpu macro is defined in the machine-independent
p The .Dv curproc macro is defined in
p The .Dv curlwp macro has a machine-independent definition in
a sys/lwp.h , but it may be overridden by
a machine/cpu.h , and must be overridden on architectures supporting multiprocessing and kernel preemption.
p The .Fn curcpu_stable function is defined in
a kern/subr_cpu.c . .Sh SEE ALSO .Xr cpu_number 9 , .Xr proc_find 9