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.Dd December 31, 2025 .Dt CURLWP_BIND 9 .Os .Sh NAME .Nm curlwp_bind , .Nm curlwp_bindx .Nd temporarily bind the current thread to the running CPU .Sh SYNOPSIS n sys/lwp.h .Ft int .Fn curlwp_bind "void" .Ft void .Fn curlwp_bindx "int bound" .Sh DESCRIPTION .Fn curlwp_bind temporarily binds the current thread to the running CPU and returns a cookie .Fa bound which must be passed to .Fn curlwp_bindx when done.
p During this time, the thread may sleep and may be preempted, but it will never migrate to another CPU until .Fn curlwp_bindx . If the CPU is offlined, the thread will not run again until the CPU is onlined again.
p Calls to .Fn curlwp_bind and .Fn curlwp_bindx may be nested as long as the matching cookie is passed. .Sh EXAMPLES For temporary access to resources protected by .Xr psref 9 from an arbitrary thread: d -literal struct psref psref; int bound, s; bound = curlwp_bind(); s = pserialize_read_enter(); IFADDR_READER_FOREACH(ifa, ifp) { ifa_acquire(ifa, &psref); pserialize_read_exit(s); /* * ifa is now stable, even if caller is preempted * or sleeps */ s = pserialize_read_enter(); ifa_release(ifa, &psref); } pserialize_read_exit(s); curlwp_bindx(bound); .Ed .Sh CODE REFERENCES
a sys/sys/lwp.h .Sh SEE ALSO .Xr psref 9 , .Xr pserialize 9 , .Xr localcount 9 , .Xr spl 9 .Sh HISTORY The .Nm function first appeared in .Nx 8.0 to support .Xr psref 9 .