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Commit | Line | Data |
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457c8996 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
78634061 FW |
2 | /* |
3 | * Housekeeping management. Manage the targets for routine code that can run on | |
4 | * any CPU: unbound workqueues, timers, kthreads and any offloadable work. | |
5 | * | |
6 | * Copyright (C) 2017 Red Hat, Inc., Frederic Weisbecker | |
1bda3f80 | 7 | * Copyright (C) 2017-2018 SUSE, Frederic Weisbecker |
78634061 FW |
8 | * |
9 | */ | |
d84b3131 | 10 | #include "sched.h" |
78634061 | 11 | |
dfcb245e IM |
12 | DEFINE_STATIC_KEY_FALSE(housekeeping_overridden); |
13 | EXPORT_SYMBOL_GPL(housekeeping_overridden); | |
7e56a1cf | 14 | static cpumask_var_t housekeeping_mask; |
de201559 | 15 | static unsigned int housekeeping_flags; |
7e56a1cf | 16 | |
de201559 | 17 | int housekeeping_any_cpu(enum hk_flags flags) |
7e56a1cf | 18 | { |
dfcb245e | 19 | if (static_branch_unlikely(&housekeeping_overridden)) |
de201559 FW |
20 | if (housekeeping_flags & flags) |
21 | return cpumask_any_and(housekeeping_mask, cpu_online_mask); | |
7e56a1cf FW |
22 | return smp_processor_id(); |
23 | } | |
24 | EXPORT_SYMBOL_GPL(housekeeping_any_cpu); | |
25 | ||
de201559 | 26 | const struct cpumask *housekeeping_cpumask(enum hk_flags flags) |
7e56a1cf | 27 | { |
dfcb245e | 28 | if (static_branch_unlikely(&housekeeping_overridden)) |
de201559 FW |
29 | if (housekeeping_flags & flags) |
30 | return housekeeping_mask; | |
7e56a1cf FW |
31 | return cpu_possible_mask; |
32 | } | |
33 | EXPORT_SYMBOL_GPL(housekeeping_cpumask); | |
34 | ||
de201559 | 35 | void housekeeping_affine(struct task_struct *t, enum hk_flags flags) |
7e56a1cf | 36 | { |
dfcb245e | 37 | if (static_branch_unlikely(&housekeeping_overridden)) |
de201559 FW |
38 | if (housekeeping_flags & flags) |
39 | set_cpus_allowed_ptr(t, housekeeping_mask); | |
7e56a1cf FW |
40 | } |
41 | EXPORT_SYMBOL_GPL(housekeeping_affine); | |
42 | ||
de201559 | 43 | bool housekeeping_test_cpu(int cpu, enum hk_flags flags) |
7e56a1cf | 44 | { |
dfcb245e | 45 | if (static_branch_unlikely(&housekeeping_overridden)) |
de201559 FW |
46 | if (housekeeping_flags & flags) |
47 | return cpumask_test_cpu(cpu, housekeeping_mask); | |
7e56a1cf FW |
48 | return true; |
49 | } | |
50 | EXPORT_SYMBOL_GPL(housekeeping_test_cpu); | |
78634061 FW |
51 | |
52 | void __init housekeeping_init(void) | |
53 | { | |
6f1982fe | 54 | if (!housekeeping_flags) |
78634061 FW |
55 | return; |
56 | ||
dfcb245e | 57 | static_branch_enable(&housekeeping_overridden); |
6f1982fe | 58 | |
d84b3131 FW |
59 | if (housekeeping_flags & HK_FLAG_TICK) |
60 | sched_tick_offload_init(); | |
61 | ||
6f1982fe FW |
62 | /* We need at least one CPU to handle housekeeping work */ |
63 | WARN_ON_ONCE(cpumask_empty(housekeeping_mask)); | |
64 | } | |
65 | ||
edb93821 | 66 | static int __init housekeeping_setup(char *str, enum hk_flags flags) |
6f1982fe FW |
67 | { |
68 | cpumask_var_t non_housekeeping_mask; | |
9219565a | 69 | cpumask_var_t tmp; |
edb93821 | 70 | int err; |
6f1982fe FW |
71 | |
72 | alloc_bootmem_cpumask_var(&non_housekeeping_mask); | |
edb93821 FW |
73 | err = cpulist_parse(str, non_housekeeping_mask); |
74 | if (err < 0 || cpumask_last(non_housekeeping_mask) >= nr_cpu_ids) { | |
75 | pr_warn("Housekeeping: nohz_full= or isolcpus= incorrect CPU range\n"); | |
6f1982fe FW |
76 | free_bootmem_cpumask_var(non_housekeeping_mask); |
77 | return 0; | |
78634061 FW |
78 | } |
79 | ||
9219565a | 80 | alloc_bootmem_cpumask_var(&tmp); |
edb93821 FW |
81 | if (!housekeeping_flags) { |
82 | alloc_bootmem_cpumask_var(&housekeeping_mask); | |
83 | cpumask_andnot(housekeeping_mask, | |
84 | cpu_possible_mask, non_housekeeping_mask); | |
9219565a NP |
85 | |
86 | cpumask_andnot(tmp, cpu_present_mask, non_housekeeping_mask); | |
87 | if (cpumask_empty(tmp)) { | |
88 | pr_warn("Housekeeping: must include one present CPU, " | |
89 | "using boot CPU:%d\n", smp_processor_id()); | |
c89d92ed | 90 | __cpumask_set_cpu(smp_processor_id(), housekeeping_mask); |
9219565a NP |
91 | __cpumask_clear_cpu(smp_processor_id(), non_housekeeping_mask); |
92 | } | |
edb93821 | 93 | } else { |
9219565a NP |
94 | cpumask_andnot(tmp, cpu_present_mask, non_housekeeping_mask); |
95 | if (cpumask_empty(tmp)) | |
96 | __cpumask_clear_cpu(smp_processor_id(), non_housekeeping_mask); | |
edb93821 FW |
97 | cpumask_andnot(tmp, cpu_possible_mask, non_housekeeping_mask); |
98 | if (!cpumask_equal(tmp, housekeeping_mask)) { | |
99 | pr_warn("Housekeeping: nohz_full= must match isolcpus=\n"); | |
100 | free_bootmem_cpumask_var(tmp); | |
101 | free_bootmem_cpumask_var(non_housekeeping_mask); | |
102 | return 0; | |
103 | } | |
edb93821 | 104 | } |
9219565a | 105 | free_bootmem_cpumask_var(tmp); |
de201559 | 106 | |
edb93821 FW |
107 | if ((flags & HK_FLAG_TICK) && !(housekeeping_flags & HK_FLAG_TICK)) { |
108 | if (IS_ENABLED(CONFIG_NO_HZ_FULL)) { | |
109 | tick_nohz_full_setup(non_housekeeping_mask); | |
110 | } else { | |
111 | pr_warn("Housekeeping: nohz unsupported." | |
112 | " Build with CONFIG_NO_HZ_FULL\n"); | |
113 | free_bootmem_cpumask_var(non_housekeeping_mask); | |
114 | return 0; | |
115 | } | |
116 | } | |
e179f5a0 | 117 | |
edb93821 | 118 | housekeeping_flags |= flags; |
6f1982fe FW |
119 | |
120 | free_bootmem_cpumask_var(non_housekeeping_mask); | |
121 | ||
122 | return 1; | |
78634061 | 123 | } |
edb93821 FW |
124 | |
125 | static int __init housekeeping_nohz_full_setup(char *str) | |
126 | { | |
127 | unsigned int flags; | |
128 | ||
1bda3f80 | 129 | flags = HK_FLAG_TICK | HK_FLAG_WQ | HK_FLAG_TIMER | HK_FLAG_RCU | HK_FLAG_MISC; |
edb93821 FW |
130 | |
131 | return housekeeping_setup(str, flags); | |
132 | } | |
6f1982fe | 133 | __setup("nohz_full=", housekeeping_nohz_full_setup); |
edb93821 FW |
134 | |
135 | static int __init housekeeping_isolcpus_setup(char *str) | |
136 | { | |
150dfee9 FW |
137 | unsigned int flags = 0; |
138 | ||
139 | while (isalpha(*str)) { | |
140 | if (!strncmp(str, "nohz,", 5)) { | |
141 | str += 5; | |
142 | flags |= HK_FLAG_TICK; | |
143 | continue; | |
144 | } | |
145 | ||
146 | if (!strncmp(str, "domain,", 7)) { | |
147 | str += 7; | |
148 | flags |= HK_FLAG_DOMAIN; | |
149 | continue; | |
150 | } | |
151 | ||
152 | pr_warn("isolcpus: Error, unknown flag\n"); | |
153 | return 0; | |
154 | } | |
155 | ||
156 | /* Default behaviour for isolcpus without flags */ | |
157 | if (!flags) | |
158 | flags |= HK_FLAG_DOMAIN; | |
159 | ||
160 | return housekeeping_setup(str, flags); | |
edb93821 FW |
161 | } |
162 | __setup("isolcpus=", housekeeping_isolcpus_setup); |