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9#include "sched.h"
10
11static inline int parent(int i)
12{
13 return (i - 1) >> 1;
14}
15
16static inline int left_child(int i)
17{
18 return (i << 1) + 1;
19}
20
21static inline int right_child(int i)
22{
23 return (i << 1) + 2;
24}
25
26static void cpudl_heapify_down(struct cpudl *cp, int idx)
27{
28 int l, r, largest;
29
30 int orig_cpu = cp->elements[idx].cpu;
31 u64 orig_dl = cp->elements[idx].dl;
32
33 if (left_child(idx) >= cp->size)
34 return;
35
36
37 while (1) {
38 u64 largest_dl;
39
40 l = left_child(idx);
41 r = right_child(idx);
42 largest = idx;
43 largest_dl = orig_dl;
44
45 if ((l < cp->size) && dl_time_before(orig_dl,
46 cp->elements[l].dl)) {
47 largest = l;
48 largest_dl = cp->elements[l].dl;
49 }
50 if ((r < cp->size) && dl_time_before(largest_dl,
51 cp->elements[r].dl))
52 largest = r;
53
54 if (largest == idx)
55 break;
56
57
58 cp->elements[idx].cpu = cp->elements[largest].cpu;
59 cp->elements[idx].dl = cp->elements[largest].dl;
60 cp->elements[cp->elements[idx].cpu].idx = idx;
61 idx = largest;
62 }
63
64 cp->elements[idx].cpu = orig_cpu;
65 cp->elements[idx].dl = orig_dl;
66 cp->elements[cp->elements[idx].cpu].idx = idx;
67}
68
69static void cpudl_heapify_up(struct cpudl *cp, int idx)
70{
71 int p;
72
73 int orig_cpu = cp->elements[idx].cpu;
74 u64 orig_dl = cp->elements[idx].dl;
75
76 if (idx == 0)
77 return;
78
79 do {
80 p = parent(idx);
81 if (dl_time_before(orig_dl, cp->elements[p].dl))
82 break;
83
84 cp->elements[idx].cpu = cp->elements[p].cpu;
85 cp->elements[idx].dl = cp->elements[p].dl;
86 cp->elements[cp->elements[idx].cpu].idx = idx;
87 idx = p;
88 } while (idx != 0);
89
90 cp->elements[idx].cpu = orig_cpu;
91 cp->elements[idx].dl = orig_dl;
92 cp->elements[cp->elements[idx].cpu].idx = idx;
93}
94
95static void cpudl_heapify(struct cpudl *cp, int idx)
96{
97 if (idx > 0 && dl_time_before(cp->elements[parent(idx)].dl,
98 cp->elements[idx].dl))
99 cpudl_heapify_up(cp, idx);
100 else
101 cpudl_heapify_down(cp, idx);
102}
103
104static inline int cpudl_maximum(struct cpudl *cp)
105{
106 return cp->elements[0].cpu;
107}
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116
117int cpudl_find(struct cpudl *cp, struct task_struct *p,
118 struct cpumask *later_mask)
119{
120 const struct sched_dl_entity *dl_se = &p->dl;
121
122 if (later_mask &&
123 cpumask_and(later_mask, cp->free_cpus, &p->cpus_mask)) {
124 unsigned long cap, max_cap = 0;
125 int cpu, max_cpu = -1;
126
127 if (!static_branch_unlikely(&sched_asym_cpucapacity))
128 return 1;
129
130
131 for_each_cpu(cpu, later_mask) {
132 if (!dl_task_fits_capacity(p, cpu)) {
133 cpumask_clear_cpu(cpu, later_mask);
134
135 cap = capacity_orig_of(cpu);
136
137 if (cap > max_cap ||
138 (cpu == task_cpu(p) && cap == max_cap)) {
139 max_cap = cap;
140 max_cpu = cpu;
141 }
142 }
143 }
144
145 if (cpumask_empty(later_mask))
146 cpumask_set_cpu(max_cpu, later_mask);
147
148 return 1;
149 } else {
150 int best_cpu = cpudl_maximum(cp);
151
152 WARN_ON(best_cpu != -1 && !cpu_present(best_cpu));
153
154 if (cpumask_test_cpu(best_cpu, &p->cpus_mask) &&
155 dl_time_before(dl_se->deadline, cp->elements[0].dl)) {
156 if (later_mask)
157 cpumask_set_cpu(best_cpu, later_mask);
158
159 return 1;
160 }
161 }
162 return 0;
163}
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173
174void cpudl_clear(struct cpudl *cp, int cpu)
175{
176 int old_idx, new_cpu;
177 unsigned long flags;
178
179 WARN_ON(!cpu_present(cpu));
180
181 raw_spin_lock_irqsave(&cp->lock, flags);
182
183 old_idx = cp->elements[cpu].idx;
184 if (old_idx == IDX_INVALID) {
185
186
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188
189
190 } else {
191 new_cpu = cp->elements[cp->size - 1].cpu;
192 cp->elements[old_idx].dl = cp->elements[cp->size - 1].dl;
193 cp->elements[old_idx].cpu = new_cpu;
194 cp->size--;
195 cp->elements[new_cpu].idx = old_idx;
196 cp->elements[cpu].idx = IDX_INVALID;
197 cpudl_heapify(cp, old_idx);
198
199 cpumask_set_cpu(cpu, cp->free_cpus);
200 }
201 raw_spin_unlock_irqrestore(&cp->lock, flags);
202}
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213
214void cpudl_set(struct cpudl *cp, int cpu, u64 dl)
215{
216 int old_idx;
217 unsigned long flags;
218
219 WARN_ON(!cpu_present(cpu));
220
221 raw_spin_lock_irqsave(&cp->lock, flags);
222
223 old_idx = cp->elements[cpu].idx;
224 if (old_idx == IDX_INVALID) {
225 int new_idx = cp->size++;
226
227 cp->elements[new_idx].dl = dl;
228 cp->elements[new_idx].cpu = cpu;
229 cp->elements[cpu].idx = new_idx;
230 cpudl_heapify_up(cp, new_idx);
231 cpumask_clear_cpu(cpu, cp->free_cpus);
232 } else {
233 cp->elements[old_idx].dl = dl;
234 cpudl_heapify(cp, old_idx);
235 }
236
237 raw_spin_unlock_irqrestore(&cp->lock, flags);
238}
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245void cpudl_set_freecpu(struct cpudl *cp, int cpu)
246{
247 cpumask_set_cpu(cpu, cp->free_cpus);
248}
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254
255void cpudl_clear_freecpu(struct cpudl *cp, int cpu)
256{
257 cpumask_clear_cpu(cpu, cp->free_cpus);
258}
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263
264int cpudl_init(struct cpudl *cp)
265{
266 int i;
267
268 raw_spin_lock_init(&cp->lock);
269 cp->size = 0;
270
271 cp->elements = kcalloc(nr_cpu_ids,
272 sizeof(struct cpudl_item),
273 GFP_KERNEL);
274 if (!cp->elements)
275 return -ENOMEM;
276
277 if (!zalloc_cpumask_var(&cp->free_cpus, GFP_KERNEL)) {
278 kfree(cp->elements);
279 return -ENOMEM;
280 }
281
282 for_each_possible_cpu(i)
283 cp->elements[i].idx = IDX_INVALID;
284
285 return 0;
286}
287
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291
292void cpudl_cleanup(struct cpudl *cp)
293{
294 free_cpumask_var(cp->free_cpus);
295 kfree(cp->elements);
296}
297