Ivo van Poorten
/
opus-una
A Small Cooperative Multitasking Kernel
kernel.h@0:73b89fc74e9f, 2011-07-24 (annotated)
- Committer:
- Ivop
- Date:
- Sun Jul 24 17:15:42 2011 +0000
- Revision:
- 0:73b89fc74e9f
first release
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
Ivop | 0:73b89fc74e9f | 1 | /* Opus Una - A Small Cooperative Multitasking Kernel in C |
Ivop | 0:73b89fc74e9f | 2 | * |
Ivop | 0:73b89fc74e9f | 3 | * Copyright (C) 2011 by Ivo van Poorten <ivop@euronet.nl> |
Ivop | 0:73b89fc74e9f | 4 | * This file is licensed under the terms of the GNU Lesser |
Ivop | 0:73b89fc74e9f | 5 | * General Public License, version 3. |
Ivop | 0:73b89fc74e9f | 6 | */ |
Ivop | 0:73b89fc74e9f | 7 | |
Ivop | 0:73b89fc74e9f | 8 | #ifndef OU_KERNEL_H |
Ivop | 0:73b89fc74e9f | 9 | #define OU_KERNEL_H |
Ivop | 0:73b89fc74e9f | 10 | |
Ivop | 0:73b89fc74e9f | 11 | #ifndef NULL |
Ivop | 0:73b89fc74e9f | 12 | #define NULL ((void *)0) |
Ivop | 0:73b89fc74e9f | 13 | #endif |
Ivop | 0:73b89fc74e9f | 14 | |
Ivop | 0:73b89fc74e9f | 15 | #define OU_VERSION 1 |
Ivop | 0:73b89fc74e9f | 16 | |
Ivop | 0:73b89fc74e9f | 17 | #define OU_CONCAT2(x,y) x##y |
Ivop | 0:73b89fc74e9f | 18 | #define OU_CONCAT(x,y) OU_CONCAT2(x,y) |
Ivop | 0:73b89fc74e9f | 19 | |
Ivop | 0:73b89fc74e9f | 20 | #define OU_TASK(name) static void name(void) { if(ou_state) goto *ou_state; { |
Ivop | 0:73b89fc74e9f | 21 | #define OU_ENDTASK OU_SUSPEND; ou_wait=0; }} |
Ivop | 0:73b89fc74e9f | 22 | |
Ivop | 0:73b89fc74e9f | 23 | #define OU_WAIT(ticks) { ou_wait = ticks; ou_state = &&OU_CONCAT(L,__LINE__); return; } \ |
Ivop | 0:73b89fc74e9f | 24 | OU_CONCAT(L,__LINE__): |
Ivop | 0:73b89fc74e9f | 25 | |
Ivop | 0:73b89fc74e9f | 26 | #define OU_YIELD do{ OU_WAIT(0); }while(0) |
Ivop | 0:73b89fc74e9f | 27 | #define OU_SUSPEND do{ ou_tasks[ou_current_task].suspended = 1; OU_WAIT(0); }while(0) |
Ivop | 0:73b89fc74e9f | 28 | #define OU_START(t) do{ ou_tasks[t].suspended = 0; OU_WAIT(0); }while(0) |
Ivop | 0:73b89fc74e9f | 29 | |
Ivop | 0:73b89fc74e9f | 30 | #define OU_GET_TASK_PRIORITY(t) ou_tasks[t].priority |
Ivop | 0:73b89fc74e9f | 31 | #define OU_SET_TASK_PRIORITY(t,p) ou_tasks[t].priority = p |
Ivop | 0:73b89fc74e9f | 32 | |
Ivop | 0:73b89fc74e9f | 33 | #define OU_GET_MY_PRIORITY() OU_GET_TASK_PRIORITY(ou_current_task) |
Ivop | 0:73b89fc74e9f | 34 | #define OU_SET_MY_PRIORITY(p) OU_SET_TASK_PRIORITY(ou_current_task,p) |
Ivop | 0:73b89fc74e9f | 35 | |
Ivop | 0:73b89fc74e9f | 36 | // Note: Locks only work between tasks, NOT between tasks and interrupt handlers. |
Ivop | 0:73b89fc74e9f | 37 | // For that, we need a full-blown mutex |
Ivop | 0:73b89fc74e9f | 38 | |
Ivop | 0:73b89fc74e9f | 39 | #define OU_LOCK(i) while(!i) OU_WAIT(1); i=1 |
Ivop | 0:73b89fc74e9f | 40 | #define OU_UNLOCK(i) i=0 |
Ivop | 0:73b89fc74e9f | 41 | |
Ivop | 0:73b89fc74e9f | 42 | struct ou_task { |
Ivop | 0:73b89fc74e9f | 43 | void (*function)(void); // entry point of task |
Ivop | 0:73b89fc74e9f | 44 | volatile unsigned priority, // 0 is highest, UINT_MAX-1 is lowest |
Ivop | 0:73b89fc74e9f | 45 | suspended, // task is suspended (=1) |
Ivop | 0:73b89fc74e9f | 46 | wait; // ticks to wait before running again |
Ivop | 0:73b89fc74e9f | 47 | unsigned delayed; // # of times scheduling was delayed |
Ivop | 0:73b89fc74e9f | 48 | void *state; // current state within function |
Ivop | 0:73b89fc74e9f | 49 | }; |
Ivop | 0:73b89fc74e9f | 50 | |
Ivop | 0:73b89fc74e9f | 51 | void ou_update_tasks(void); // called from timer interrupt |
Ivop | 0:73b89fc74e9f | 52 | void ou_scheduler(void); // main loop |
Ivop | 0:73b89fc74e9f | 53 | |
Ivop | 0:73b89fc74e9f | 54 | extern struct ou_task ou_tasks[]; |
Ivop | 0:73b89fc74e9f | 55 | extern void *ou_state; |
Ivop | 0:73b89fc74e9f | 56 | extern unsigned ou_wait, ou_current_task, ou_ticks; |
Ivop | 0:73b89fc74e9f | 57 | extern const unsigned ou_ntasks; |
Ivop | 0:73b89fc74e9f | 58 | |
Ivop | 0:73b89fc74e9f | 59 | #endif |