1 .\" Copyright (c) 2003 Hiten M. Pandya
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33 .Nd a framework for dynamic kernel initialization
37 .Fn SYSINIT "uniquifier" "enum sysinit_sub_id subsystem" "enum sysinit_elem_order order" "sysinit_cfunc_t func" "const void *ident"
38 .Fn SYSUNINIT "uniquifier" "enum sysinit_sub_id subsystem" "enum sysinit_elem_order order" "sysinit_cfunc_t func" "const void *ident"
41 is a mechanism for scheduling the execution of initialization and teardown
43 This is similar to init and fini routines with the addition of explicit
45 It allows runtime ordering of subsystem initialization in the kernel as well
46 as kernel modules (KLDs).
52 and stores it in a startup linker set.
55 type as well as the subsystem identifier constants
57 and initialization ordering constants
63 enum sysinit_sub_id subsystem; /* subsystem identifier*/
64 enum sysinit_elem_order order; /* init order within subsystem*/
65 sysinit_cfunc_t func; /* function */
66 const void *udata; /* multiplexer/argument */
74 argument to identify the particular function dispatch data,
77 type of startup interface, the subsystem element
79 of initialization within the subsystem, the
82 and the data specified in
84 argument to pass the function.
88 macro behaves similarly to the
90 macro except that it adds the data to a shutdown linker set.
92 The startup linker set for the kernel is scanned during boot to build a
93 sorted list of initialization routines.
94 The initialization routines are then executed in the sorted order.
97 is used as the primary key and is sorted in ascending order.
100 is used as the secondary key and is sorted in ascending order.
101 The relative order of two routines that have the same
107 The startup linker sets for modules that are loaded together with the kernel
108 by the boot loader are scanned during the
110 subsystem initialization.
111 These modules' initialization routines are sorted and merged into the kernel's
112 list of startup routines and are executed during boot along with the kernel's
113 initialization routines.
114 Note that this has the effect that any initialization routines in a kernel
115 module that are scheduled earlier than
117 are not executed until after
121 The startup linker set for a kernel module loaded at runtime via
123 is scanned, sorted, and executed when the module is loaded.
125 The shutdown linker set for a kernel module is scanned, sorted, and executed
126 when a kernel module is unloaded.
127 The teardown routines are sorted in the reverse order of the initialization
129 The teardown routines of the kernel and any loaded modules are
131 executed during shutdown.
133 This example shows the SYSINIT which displays the copyright notice during boot:
134 .Bd -literal -offset indent
136 print_caddr_t(void *data)
138 printf("%s", (char *)data);
140 SYSINIT(announce, SI_SUB_COPYRIGHT, SI_ORDER_FIRST, print_caddr_t,
145 .Xr DECLARE_MODULE 9 ,
147 .Xr DRIVER_MODULE 9 ,
153 framework first appeared in
159 framework was written by
160 .An Terrence Lambert Aq terry@FreeBSD.org .
162 This manual page was written by
163 .An Hiten Pandya Aq hmp@FreeBSD.org .