1 .\" Copyright (c) 2003 Hiten M. Pandya
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31 .Nd a framework for dynamic kernel initialization
35 .Fn SYSINIT "uniquifier" "enum sysinit_sub_id subsystem" "enum sysinit_elem_order order" "sysinit_cfunc_t func" "const void *ident"
36 .Fn SYSUNINIT "uniquifier" "enum sysinit_sub_id subsystem" "enum sysinit_elem_order order" "sysinit_cfunc_t func" "const void *ident"
39 is a mechanism for scheduling the execution of initialization and teardown
41 This is similar to init and fini routines with the addition of explicit
43 It allows runtime ordering of subsystem initialization in the kernel as well
44 as kernel modules (KLDs).
50 and stores it in a startup linker set.
53 type as well as the subsystem identifier constants
55 and initialization ordering constants
61 enum sysinit_sub_id subsystem; /* subsystem identifier*/
62 enum sysinit_elem_order order; /* init order within subsystem*/
63 sysinit_cfunc_t func; /* function */
64 const void *udata; /* multiplexer/argument */
72 argument to identify the particular function dispatch data,
75 type of startup interface, the subsystem element
77 of initialization within the subsystem, the
80 and the data specified in
82 argument to pass the function.
86 macro behaves similarly to the
88 macro except that it adds the data to a shutdown linker set.
90 The startup linker set for the kernel is scanned during boot to build a
91 sorted list of initialization routines.
92 The initialization routines are then executed in the sorted order.
95 is used as the primary key and is sorted in ascending order.
98 is used as the secondary key and is sorted in ascending order.
99 The relative order of two routines that have the same
105 The startup linker sets for modules that are loaded together with the kernel
106 by the boot loader are scanned during the
108 subsystem initialization.
109 These modules' initialization routines are sorted and merged into the kernel's
110 list of startup routines and are executed during boot along with the kernel's
111 initialization routines.
112 Note that this has the effect that any initialization routines in a kernel
113 module that are scheduled earlier than
115 are not executed until after
119 The startup linker set for a kernel module loaded at runtime via
121 is scanned, sorted, and executed when the module is loaded.
123 The shutdown linker set for a kernel module is scanned, sorted, and executed
124 when a kernel module is unloaded.
125 The teardown routines are sorted in the reverse order of the initialization
127 The teardown routines of the kernel and any loaded modules are
129 executed during shutdown.
131 This example shows the SYSINIT which displays the copyright notice during boot:
132 .Bd -literal -offset indent
134 print_caddr_t(void *data)
136 printf("%s", (char *)data);
138 SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t,
143 .Xr DECLARE_MODULE 9 ,
145 .Xr DRIVER_MODULE 9 ,
151 framework first appeared in
157 framework was written by
158 .An Terrence Lambert Aq Mt terry@FreeBSD.org .
160 This manual page was written by
161 .An Hiten Pandya Aq Mt hmp@FreeBSD.org .