Copyright (c) 2000 Christopher G. Demetriou.
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.Dd May 30, 2000 .Dt SOFTINTR 9 .Os .Sh NAME .Nm softintr , .Nm softintr_establish , .Nm softintr_disestablish , .Nm softintr_schedule .Nd machine-independent software interrupt framework .Sh SYNOPSIS .Fd #include <machine/intr.h> .Ft void * .Fn softintr_establish "int level" "int (*fun)(void *)" "void *arg" .Ft void .Fn softintr_disestablish "void *cookie" .Ft void .Fn softintr_schedule "void *cookie" .Sh DESCRIPTION The .Nx machine-independent software interrupt framework is designed to provide a generic software interrupt mechanism which can be used any time a low-priority callback is needed. It allows dynamic registration of software interrupts for loadable drivers and protocol stacks, prioritization and fair queueing of software interrupts, and allows machine-dependent optimizations to reduce cost and code complexity.
p In order to provide this framework, the machine-dependent .Aq Pa machine/intr.h include file must provide prototypes for the .Nm functions, must define the .Dv __GENERIC_SOFT_INTERRUPTS symbol (without a value), and must provide definitions of several constants which define software interrupt priority levels (IPLs): l -tag -width "IPL_SOFTSERIAL" t Dv IPL_SOFTCLOCK The software IPL for software clock interrupts
q i.e., Fn softclock . t Dv IPL_SOFTNET The software IPL for network callbacks. t Dv IPL_SOFTSERIAL The software IPL for serial driver callbacks. .El
p Other constants of the form .Dv IPL_SOFT* are reserved for future use by this framework.
p The following is a brief description of each function in the framework: l -tag -width "softintr_disestablish()" t Fn softintr_establish Register a software interrupt at level .Fa level , which will call the function .Fa fun with one argument, .Fa arg . It may allocate a machine-specific data structure. If successful, .Fn softintr_establish returns a
f non- Dv NULL
opaque cookie which can be used as an argument to
.Fn softintr_schedule
or
.Fn softintr_disestablish .
If for some reason it does not succeed, it returns
.Dv NULL .
t Fn softintr_disestablish Deallocate a software interrupt previously allocated
by a call to
.Fn softintr_establish .
XXX What happens to pending scheduled calls?
t Fn softintr_schedule Schedule a software interrupt previously allocated
by a call to
.Fn softintr_establish
to be executed as soon as that software interrupt is unblocked.
This function may assume that the interrupt is currently blocked,
so it need not check to see if the interrupt needs to be executed
immediately.
.El
.Sh AUTHOR
The
.Nx
machine-independent software interrupt framework was designed by
Charles Hannum <mycroft (at] NetBSD.ORG>.
.Sh SEE ALSO
.Xr spl 9
.Sh HISTORY
The
.Nx
machine-independent software interrupt framework was designed in 1997
and was implemented by one port in
.Nx 1.3 .
However, it did not gain wider implementation until
.Nx 1.5 .
Indexes created Wed Oct 22 13:09:56 GMT 2025