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Diffstat (limited to 'include/litmus/rt_param.h')
-rw-r--r-- | include/litmus/rt_param.h | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/include/litmus/rt_param.h b/include/litmus/rt_param.h new file mode 100644 index 000000000000..c599f848d1ed --- /dev/null +++ b/include/litmus/rt_param.h | |||
@@ -0,0 +1,175 @@ | |||
1 | /* | ||
2 | * Definition of the scheduler plugin interface. | ||
3 | * | ||
4 | */ | ||
5 | #ifndef _LINUX_RT_PARAM_H_ | ||
6 | #define _LINUX_RT_PARAM_H_ | ||
7 | |||
8 | /* Litmus time type. */ | ||
9 | typedef unsigned long long lt_t; | ||
10 | |||
11 | static inline int lt_after(lt_t a, lt_t b) | ||
12 | { | ||
13 | return ((long long) b) - ((long long) a) < 0; | ||
14 | } | ||
15 | #define lt_before(a, b) lt_after(b, a) | ||
16 | |||
17 | static inline int lt_after_eq(lt_t a, lt_t b) | ||
18 | { | ||
19 | return ((long long) a) - ((long long) b) >= 0; | ||
20 | } | ||
21 | #define lt_before_eq(a, b) lt_after_eq(b, a) | ||
22 | |||
23 | /* different types of clients */ | ||
24 | typedef enum { | ||
25 | RT_CLASS_HARD, | ||
26 | RT_CLASS_SOFT, | ||
27 | RT_CLASS_BEST_EFFORT | ||
28 | } task_class_t; | ||
29 | |||
30 | struct rt_task { | ||
31 | lt_t exec_cost; | ||
32 | lt_t period; | ||
33 | lt_t phase; | ||
34 | unsigned int cpu; | ||
35 | task_class_t cls; | ||
36 | }; | ||
37 | |||
38 | /* don't export internal data structures to user space (liblitmus) */ | ||
39 | #ifdef __KERNEL__ | ||
40 | |||
41 | struct _rt_domain; | ||
42 | struct heap_node; | ||
43 | struct release_heap; | ||
44 | |||
45 | struct rt_job { | ||
46 | /* Time instant the the job was or will be released. */ | ||
47 | lt_t release; | ||
48 | /* What is the current deadline? */ | ||
49 | lt_t deadline; | ||
50 | |||
51 | /* How much service has this job received so far? */ | ||
52 | lt_t exec_time; | ||
53 | |||
54 | /* Which job is this. This is used to let user space | ||
55 | * specify which job to wait for, which is important if jobs | ||
56 | * overrun. If we just call sys_sleep_next_period() then we | ||
57 | * will unintentionally miss jobs after an overrun. | ||
58 | * | ||
59 | * Increase this sequence number when a job is released. | ||
60 | */ | ||
61 | unsigned int job_no; | ||
62 | }; | ||
63 | |||
64 | |||
65 | struct pfair_param; | ||
66 | |||
67 | /* RT task parameters for scheduling extensions | ||
68 | * These parameters are inherited during clone and therefore must | ||
69 | * be explicitly set up before the task set is launched. | ||
70 | */ | ||
71 | struct rt_param { | ||
72 | /* is the task sleeping? */ | ||
73 | unsigned int flags:8; | ||
74 | |||
75 | /* do we need to check for srp blocking? */ | ||
76 | unsigned int srp_non_recurse:1; | ||
77 | |||
78 | /* is the task present? (true if it can be scheduled) */ | ||
79 | unsigned int present:1; | ||
80 | |||
81 | /* user controlled parameters */ | ||
82 | struct rt_task task_params; | ||
83 | |||
84 | /* timing parameters */ | ||
85 | struct rt_job job_params; | ||
86 | |||
87 | /* task representing the current "inherited" task | ||
88 | * priority, assigned by inherit_priority and | ||
89 | * return priority in the scheduler plugins. | ||
90 | * could point to self if PI does not result in | ||
91 | * an increased task priority. | ||
92 | */ | ||
93 | struct task_struct* inh_task; | ||
94 | |||
95 | /* Don't just dereference this pointer in kernel space! | ||
96 | * It might very well point to junk or nothing at all. | ||
97 | * NULL indicates that the task has not requested any non-preemptable | ||
98 | * section support. | ||
99 | * Not inherited upon fork. | ||
100 | */ | ||
101 | short* np_flag; | ||
102 | |||
103 | /* re-use unused counter in plugins that don't need it */ | ||
104 | union { | ||
105 | /* For the FMLP under PSN-EDF, it is required to make the task | ||
106 | * non-preemptive from kernel space. In order not to interfere with | ||
107 | * user space, this counter indicates the kernel space np setting. | ||
108 | * kernel_np > 0 => task is non-preemptive | ||
109 | */ | ||
110 | unsigned int kernel_np; | ||
111 | |||
112 | /* Used by GQ-EDF */ | ||
113 | unsigned int last_cpu; | ||
114 | }; | ||
115 | |||
116 | /* This field can be used by plugins to store where the task | ||
117 | * is currently scheduled. It is the responsibility of the | ||
118 | * plugin to avoid race conditions. | ||
119 | * | ||
120 | * This used by GSN-EDF and PFAIR. | ||
121 | */ | ||
122 | volatile int scheduled_on; | ||
123 | |||
124 | /* Is the stack of the task currently in use? This is updated by | ||
125 | * the LITMUS core. | ||
126 | * | ||
127 | * Be careful to avoid deadlocks! | ||
128 | */ | ||
129 | volatile int stack_in_use; | ||
130 | |||
131 | /* This field can be used by plugins to store where the task | ||
132 | * is currently linked. It is the responsibility of the plugin | ||
133 | * to avoid race conditions. | ||
134 | * | ||
135 | * Used by GSN-EDF. | ||
136 | */ | ||
137 | volatile int linked_on; | ||
138 | |||
139 | /* PFAIR/PD^2 state. Allocated on demand. */ | ||
140 | struct pfair_param* pfair; | ||
141 | |||
142 | /* Fields saved before BE->RT transition. | ||
143 | */ | ||
144 | int old_policy; | ||
145 | int old_prio; | ||
146 | |||
147 | /* ready queue for this task */ | ||
148 | struct _rt_domain* domain; | ||
149 | |||
150 | /* heap element for this task | ||
151 | * | ||
152 | * Warning: Don't statically allocate this node. The heap | ||
153 | * implementation swaps these between tasks, thus after | ||
154 | * dequeuing from a heap you may end up with a different node | ||
155 | * then the one you had when enqueuing the task. For the same | ||
156 | * reason, don't obtain and store references to this node | ||
157 | * other than this pointer (which is updated by the heap | ||
158 | * implementation). | ||
159 | */ | ||
160 | struct heap_node* heap_node; | ||
161 | struct release_heap* rel_heap; | ||
162 | |||
163 | /* Used by rt_domain to queue task in release list. | ||
164 | */ | ||
165 | struct list_head list; | ||
166 | }; | ||
167 | |||
168 | /* Possible RT flags */ | ||
169 | #define RT_F_RUNNING 0x00000000 | ||
170 | #define RT_F_SLEEP 0x00000001 | ||
171 | #define RT_F_EXIT_SEM 0x00000008 | ||
172 | |||
173 | #endif | ||
174 | |||
175 | #endif | ||