/* * Early initcalls run before initializing SMP. * * Only for built-in code, not modules. */ #define early_initcall(fn) __define_initcall(fn, early)
/* * A "pure" initcall has no dependencies on anything else, and purely * initializes variables that couldn't be statically initialized. * * This only exists for built-in code, not for modules. * Keep main.c:initcall_level_names[] in sync. */ #define pure_initcall(fn) __define_initcall(fn, 0)
int __init_or_module do_one_initcall(initcall_t fn) { ... do_trace_initcall_start(fn); ret = fn(); do_trace_initcall_finish(fn, ret); ... return ret; }
作为模块加载的initcall
作为模块加载所使用的initcall略有不同。
定义如下:
#define __initcall(fn) device_initcall(fn)
#ifndef MODULE /** * module_init() - driver initialization entry point * @x: function to be run at kernel boot time or module insertion * * module_init() will either be called during do_initcalls() (if * builtin) or at module insertion time (if a module). There can only * be one per module. */ #define module_init(x) __initcall(x);
/** * module_exit() - driver exit entry point * @x: function to be run when driver is removed * * module_exit() will wrap the driver clean-up code * with cleanup_module() when used with rmmod when * the driver is a module. If the driver is statically * compiled into the kernel, module_exit() has no effect. * There can only be one per module. */ #define module_exit(x) __exitcall(x);
#else/* MODULE */
/* * In most cases loadable modules do not need custom * initcall levels. There are still some valid cases where * a driver may be needed early if built in, and does not * matter when built as a loadable module. Like bus * snooping debug drivers. */ #define early_initcall(fn) module_init(fn) #define core_initcall(fn) module_init(fn) #define core_initcall_sync(fn) module_init(fn) #define postcore_initcall(fn) module_init(fn) #define postcore_initcall_sync(fn) module_init(fn) #define arch_initcall(fn) module_init(fn) #define subsys_initcall(fn) module_init(fn) #define subsys_initcall_sync(fn) module_init(fn) #define fs_initcall(fn) module_init(fn) #define fs_initcall_sync(fn) module_init(fn) #define rootfs_initcall(fn) module_init(fn) #define device_initcall(fn) module_init(fn) #define device_initcall_sync(fn) module_init(fn) #define late_initcall(fn) module_init(fn) #define late_initcall_sync(fn) module_init(fn)
#define console_initcall(fn) module_init(fn)
/* Each module must use one module_init(). */ #define module_init(initfn) \ static inline initcall_t __maybe_unused __inittest(void) \ { return initfn; } \ int init_module(void) __copy(initfn) \ __attribute__((alias(#initfn))); \ ___ADDRESSABLE(init_module, __initdata);
/* This is only required if you want to be unloadable. */ #define module_exit(exitfn) \ static inline exitcall_t __maybe_unused __exittest(void) \ { return exitfn; } \ void cleanup_module(void) __copy(exitfn) \ __attribute__((alias(#exitfn))); \ ___ADDRESSABLE(cleanup_module, __exitdata);
