| 1 |
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| 2 | |
| 3 | * Copyright (C) 2019-2022 Red Hat, Inc. Daniel Bristot de Oliveira <[email protected]>
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| 4 | *
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| 5 | * Deterministic automata (DA) monitor functions, to be used together
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| 6 | * with automata models in C generated by the rvgen tool.
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| 7 | *
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| 8 | * The rvgen tool is available at tools/verification/rvgen/
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| 9 | *
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| 10 | * For further information, see:
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| 11 | * Documentation/trace/rv/monitor_synthesis.rst
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| 12 |
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| 13 |
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| 14 | #ifndef _RV_DA_MONITOR_H
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| 15 | #define _RV_DA_MONITOR_H
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| 16 |
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| 17 | #include <rv/automata.h>
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| 18 | #include <linux/rv.h>
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| 19 | #include <rv/kunit.h>
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| 20 | #include <linux/stringify.h>
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| 21 | #include <linux/bug.h>
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| 22 | #include <linux/sched.h>
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| 23 | #include <linux/slab.h>
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| 24 | #include <linux/hashtable.h>
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| 25 |
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| 26 | |
| 27 | * Per-cpu variables require a unique name although static in some
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| 28 | * configurations (e.g. alpha modules).
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| 29 |
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| 30 | #define DA_MON_NAME CONCATENATE(da_mon_, MONITOR_NAME)
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| 31 |
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| 32 | static struct rv_monitor rv_this;
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| 33 |
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| 34 | |
| 35 | * Hook to allow the implementation of hybrid automata: define it with a
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| 36 | * function that takes curr_state, event and next_state and returns true if the
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| 37 | * environment constraints (e.g. timing) are satisfied, false otherwise.
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| 38 |
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| 39 | #ifndef da_monitor_event_hook
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| 40 | #define da_monitor_event_hook(...) true
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| 41 | #endif
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| 42 |
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| 43 | |
| 44 | * Hook to allow the implementation of hybrid automata: define it with a
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| 45 | * function that takes the da_monitor and performs further initialisation
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| 46 | * (e.g. reset set up timers).
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| 47 |
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| 48 | #ifndef da_monitor_init_hook
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| 49 | #define da_monitor_init_hook(da_mon)
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| 50 | #endif
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| 51 |
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| 52 | |
| 53 | * Hook to allow the implementation of hybrid automata: define it with a
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| 54 | * function that takes the da_monitor and performs further reset (e.g. reset
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| 55 | * all clocks).
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| 56 |
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| 57 | #ifndef da_monitor_reset_hook
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| 58 | #define da_monitor_reset_hook(da_mon)
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| 59 | #endif
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| 60 |
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| 61 | |
| 62 | * Hook to allow the implementation of hybrid automata: define it with a
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| 63 | * function that waits for the termination of all monitors background
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| 64 | * activities (e.g. all timers). This hook can sleep.
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| 65 |
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| 66 | #ifndef da_monitor_sync_hook
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| 67 | #define da_monitor_sync_hook()
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| 68 | #endif
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| 69 |
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| 70 | |
| 71 | * Type for the target id, default to int but can be overridden.
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| 72 | * A long type can work as hash table key (PER_OBJ) but will be downgraded to
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| 73 | * int in the event tracepoint.
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| 74 | * Unused for implicit monitors.
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| 75 |
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| 76 | #ifndef da_id_type
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| 77 | #define da_id_type int
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| 78 | #endif
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| 79 |
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| 80 | static void react(enum states curr_state, enum events event)
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| 81 | {
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| 82 | rv_react(&rv_this,
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| 83 | "rv: monitor %s does not allow event %s on state %s\n",
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| 84 | __stringify(MONITOR_NAME),
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| 85 | model_get_event_name(event),
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| 86 | model_get_state_name(curr_state));
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| 87 | }
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| 88 |
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| 89 | |
| 90 | * da_monitor_reset_state - reset a monitor and setting it to init state
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| 91 |
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| 92 | static inline void da_monitor_reset_state(struct da_monitor *da_mon)
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| 93 | {
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| 94 | WRITE_ONCE(da_mon->monitoring, 0);
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| 95 |
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| 96 | smp_store_release(&da_mon->curr_state, model_get_initial_state());
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| 97 | }
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| 98 |
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| 99 | |
| 100 | * da_monitor_reset - reset a monitor and setting it to init state
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| 101 |
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| 102 | static inline void da_monitor_reset(struct da_monitor *da_mon)
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| 103 | {
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| 104 | da_monitor_reset_hook(da_mon);
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| 105 | da_monitor_reset_state(da_mon);
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| 106 | }
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| 107 |
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| 108 | |
| 109 | * da_monitor_start - start monitoring
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| 110 | *
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| 111 | * The monitor will ignore all events until monitoring is set to true. This
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| 112 | * function needs to be called to tell the monitor to start monitoring.
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| 113 |
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| 114 | static inline void da_monitor_start(struct da_monitor *da_mon)
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| 115 | {
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| 116 | da_mon->curr_state = model_get_initial_state();
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| 117 | da_monitor_init_hook(da_mon);
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| 118 |
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| 119 | smp_store_release(&da_mon->monitoring, 1);
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| 120 | }
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| 121 |
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| 122 | |
| 123 | * da_monitoring - returns true if the monitor is processing events
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| 124 |
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| 125 | static inline bool da_monitoring(struct da_monitor *da_mon)
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| 126 | {
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| 127 |
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| 128 | return smp_load_acquire(&da_mon->monitoring);
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| 129 | }
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| 130 |
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| 131 | |
| 132 | * da_monitor_enabled - checks if the monitor is enabled
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| 133 |
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| 134 | static inline bool da_monitor_enabled(void)
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| 135 | {
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| 136 |
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| 137 | if (unlikely(!rv_monitoring_on()))
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| 138 | return 0;
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| 139 |
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| 140 |
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| 141 | if (unlikely(!rv_this.enabled))
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| 142 | return 0;
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| 143 |
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| 144 | return 1;
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| 145 | }
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| 146 |
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| 147 | |
| 148 | * da_monitor_handling_event - checks if the monitor is ready to handle events
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| 149 |
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| 150 | static inline bool da_monitor_handling_event(struct da_monitor *da_mon)
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| 151 | {
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| 152 | if (!da_monitor_enabled())
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| 153 | return 0;
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| 154 |
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| 155 |
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| 156 | if (unlikely(!da_monitoring(da_mon)))
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| 157 | return 0;
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| 158 |
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| 159 | return 1;
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| 160 | }
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| 161 |
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| 162 | #if RV_MON_TYPE == RV_MON_GLOBAL
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| 163 | |
| 164 | * Functions to define, init and get a global monitor.
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| 165 |
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| 166 |
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| 167 | |
| 168 | * global monitor (a single variable)
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| 169 |
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| 170 | static struct da_monitor DA_MON_NAME;
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| 171 |
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| 172 | |
| 173 | * da_get_monitor - return the global monitor address
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| 174 |
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| 175 | static struct da_monitor *da_get_monitor(void)
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| 176 | {
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| 177 | return &DA_MON_NAME;
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| 178 | }
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| 179 |
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| 180 | |
| 181 | * __da_monitor_reset_all - reset the single monitor
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| 182 |
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| 183 | static void __da_monitor_reset_all(void (*reset)(struct da_monitor *))
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| 184 | {
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| 185 | reset(da_get_monitor());
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| 186 | }
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| 187 |
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| 188 | |
| 189 | * da_monitor_reset_all - reset the single monitor
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| 190 |
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| 191 | static void da_monitor_reset_all(void)
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| 192 | {
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| 193 | __da_monitor_reset_all(da_monitor_reset);
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| 194 | }
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| 195 |
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| 196 | |
| 197 | * da_monitor_reset_state_all - reset the single monitor
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| 198 |
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| 199 | static inline void da_monitor_reset_state_all(void)
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| 200 | {
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| 201 | __da_monitor_reset_all(da_monitor_reset_state);
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| 202 | }
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| 203 |
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| 204 | |
| 205 | * da_monitor_init - initialize a monitor
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| 206 |
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| 207 | static inline int da_monitor_init(void)
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| 208 | {
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| 209 | da_monitor_reset_state_all();
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| 210 | return 0;
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| 211 | }
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| 212 |
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| 213 | |
| 214 | * da_monitor_destroy - destroy the monitor
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| 215 |
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| 216 | static inline void da_monitor_destroy(void)
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| 217 | {
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| 218 | da_monitor_reset_all();
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| 219 | da_monitor_sync_hook();
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| 220 | }
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| 221 |
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| 222 | #ifndef da_implicit_guard
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| 223 | #define da_implicit_guard()
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| 224 | #endif
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| 225 |
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| 226 | #elif RV_MON_TYPE == RV_MON_PER_CPU
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| 227 | |
| 228 | * Functions to define, init and get a per-cpu monitor.
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| 229 |
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| 230 |
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| 231 | |
| 232 | * per-cpu monitor variables
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| 233 |
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| 234 | static DEFINE_PER_CPU(struct da_monitor, DA_MON_NAME);
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| 235 |
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| 236 | |
| 237 | * da_get_monitor - return current CPU monitor address
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| 238 |
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| 239 | static struct da_monitor *da_get_monitor(void)
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| 240 | {
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| 241 | return this_cpu_ptr(&DA_MON_NAME);
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| 242 | }
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| 243 |
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| 244 | |
| 245 | * __da_monitor_reset_all - reset all CPUs' monitor
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| 246 |
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| 247 | static void __da_monitor_reset_all(void (*reset)(struct da_monitor *))
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| 248 | {
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| 249 | struct da_monitor *da_mon;
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| 250 | int cpu;
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| 251 |
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| 252 | for_each_cpu(cpu, cpu_online_mask) {
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| 253 | da_mon = per_cpu_ptr(&DA_MON_NAME, cpu);
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| 254 | reset(da_mon);
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| 255 | }
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| 256 | }
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| 257 |
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| 258 | |
| 259 | * da_monitor_reset_all - reset all CPUs' monitor
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| 260 |
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| 261 | static void da_monitor_reset_all(void)
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| 262 | {
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| 263 | __da_monitor_reset_all(da_monitor_reset);
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| 264 | }
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| 265 |
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| 266 | |
| 267 | * da_monitor_reset_state_all - reset all CPUs' monitor
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| 268 |
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| 269 | static inline void da_monitor_reset_state_all(void)
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| 270 | {
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| 271 | __da_monitor_reset_all(da_monitor_reset_state);
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| 272 | }
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| 273 |
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| 274 | |
| 275 | * da_monitor_init - initialize all CPUs' monitor
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| 276 |
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| 277 | static inline int da_monitor_init(void)
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| 278 | {
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| 279 | da_monitor_reset_state_all();
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| 280 | return 0;
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| 281 | }
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| 282 |
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| 283 | |
| 284 | * da_monitor_destroy - destroy the monitor
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| 285 |
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| 286 | static inline void da_monitor_destroy(void)
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| 287 | {
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| 288 | da_monitor_reset_all();
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| 289 | da_monitor_sync_hook();
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| 290 | }
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| 291 |
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| 292 | #ifndef da_implicit_guard
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| 293 | #define da_implicit_guard() guard(migrate)()
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| 294 | #endif
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| 295 |
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| 296 | #elif RV_MON_TYPE == RV_MON_PER_TASK
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| 297 | |
| 298 | * Functions to define, init and get a per-task monitor.
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| 299 |
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| 300 |
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| 301 | |
| 302 | * The per-task monitor is stored a vector in the task struct. This variable
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| 303 | * stores the position on the vector reserved for this monitor.
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| 304 |
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| 305 | static int task_mon_slot = RV_PER_TASK_MONITOR_INIT;
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| 306 |
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| 307 | |
| 308 | * da_get_monitor - return the monitor in the allocated slot for tsk
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| 309 |
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| 310 | static inline struct da_monitor *da_get_monitor(struct task_struct *tsk)
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| 311 | {
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| 312 | return &tsk->rv[task_mon_slot].da_mon;
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| 313 | }
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| 314 |
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| 315 | static inline void da_reset(struct task_struct *tsk)
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| 316 | {
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| 317 | da_monitor_reset(da_get_monitor(tsk));
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| 318 | }
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| 319 |
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| 320 | |
| 321 | * da_get_target - return the task associated to the monitor
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| 322 |
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| 323 | static inline struct task_struct *da_get_target(struct da_monitor *da_mon)
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| 324 | {
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| 325 | return container_of(da_mon, struct task_struct, rv[task_mon_slot].da_mon);
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| 326 | }
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| 327 |
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| 328 | |
| 329 | * da_get_id - return the id associated to the monitor
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| 330 | *
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| 331 | * For per-task monitors, the id is the task's PID.
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| 332 |
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| 333 | static inline da_id_type da_get_id(struct da_monitor *da_mon)
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| 334 | {
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| 335 | return da_get_target(da_mon)->pid;
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| 336 | }
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| 337 |
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| 338 | static void __da_monitor_reset_all(void (*reset)(struct da_monitor *))
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| 339 | {
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| 340 | struct task_struct *g, *p;
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| 341 | int cpu;
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| 342 |
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| 343 | scoped_guard(read_lock, &tasklist_lock) {
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| 344 | for_each_process_thread(g, p)
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| 345 | reset(da_get_monitor(p));
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| 346 | }
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| 347 | for_each_present_cpu(cpu)
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| 348 | reset(da_get_monitor(idle_task(cpu)));
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| 349 | }
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| 350 |
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| 351 | static void da_monitor_reset_all(void)
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| 352 | {
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| 353 | __da_monitor_reset_all(da_monitor_reset);
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| 354 | }
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| 355 |
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| 356 | static inline void da_monitor_reset_state_all(void)
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| 357 | {
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| 358 | __da_monitor_reset_all(da_monitor_reset_state);
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| 359 | }
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| 360 |
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| 361 | |
| 362 | * da_monitor_init - initialize the per-task monitor
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| 363 | *
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| 364 | * Try to allocate a slot in the task's vector of monitors. If there
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| 365 | * is an available slot, use it and reset all task's monitor.
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| 366 |
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| 367 | static int da_monitor_init(void)
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| 368 | {
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| 369 | int slot;
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| 370 |
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| 371 | slot = rv_get_task_monitor_slot();
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| 372 | if (slot < 0 || slot >= RV_PER_TASK_MONITOR_INIT)
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| 373 | return slot;
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| 374 |
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| 375 | task_mon_slot = slot;
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| 376 |
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| 377 | da_monitor_reset_state_all();
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| 378 | return 0;
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| 379 | }
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| 380 |
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| 381 | |
| 382 | * da_monitor_destroy - return the allocated slot
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| 383 | *
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| 384 | * Wait for all in-flight handlers before returning the slot to avoid
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| 385 | * out-of-bound accesses.
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| 386 |
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| 387 | static inline void da_monitor_destroy(void)
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| 388 | {
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| 389 | if (task_mon_slot == RV_PER_TASK_MONITOR_INIT) {
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| 390 | WARN_ONCE(1, "Disabling a disabled monitor: " __stringify(MONITOR_NAME));
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| 391 | return;
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| 392 | }
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| 393 |
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| 394 | tracepoint_synchronize_unregister();
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| 395 | da_monitor_reset_all();
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| 396 | da_monitor_sync_hook();
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| 397 |
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| 398 | rv_put_task_monitor_slot(task_mon_slot);
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| 399 | task_mon_slot = RV_PER_TASK_MONITOR_INIT;
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| 400 | }
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| 401 |
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| 402 | #elif RV_MON_TYPE == RV_MON_PER_OBJ
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| 403 | |
| 404 | * Functions to define, init and get a per-object monitor.
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| 405 |
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| 406 |
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| 407 | struct da_monitor_storage {
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| 408 | da_id_type id;
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| 409 | monitor_target target;
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| 410 | union rv_task_monitor rv;
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| 411 | struct hlist_node node;
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| 412 | struct rcu_head rcu;
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| 413 | };
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| 414 |
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| 415 | #ifndef DA_MONITOR_HT_BITS
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| 416 | #define DA_MONITOR_HT_BITS 10
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| 417 | #endif
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| 418 | static DEFINE_HASHTABLE(da_monitor_ht, DA_MONITOR_HT_BITS);
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| 419 |
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| 420 | |
| 421 | * da_create_empty_storage - pre-allocate an empty storage
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| 422 |
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| 423 | static inline struct da_monitor_storage *da_create_empty_storage(da_id_type id)
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| 424 | {
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| 425 | struct da_monitor_storage *mon_storage;
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| 426 |
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| 427 | mon_storage = kmalloc_nolock(sizeof(struct da_monitor_storage),
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| 428 | __GFP_ZERO, NUMA_NO_NODE);
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| 429 | if (!mon_storage)
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| 430 | return NULL;
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| 431 |
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| 432 | hash_add_rcu(da_monitor_ht, &mon_storage->node, id);
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| 433 | mon_storage->id = id;
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| 434 | return mon_storage;
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| 435 | }
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| 436 |
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| 437 | |
| 438 | * da_create_storage - create the per-object storage
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| 439 | *
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| 440 | * The caller is responsible to synchronise writers, either with locks or
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| 441 | * implicitly. For instance, if da_create_storage is only called from a single
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| 442 | * event for target (e.g. sched_switch), it's safe to call this without locks.
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| 443 |
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| 444 | static inline struct da_monitor *da_create_storage(da_id_type id,
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| 445 | monitor_target target,
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| 446 | struct da_monitor *da_mon)
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| 447 | {
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| 448 | struct da_monitor_storage *mon_storage;
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| 449 |
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| 450 | if (da_mon)
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| 451 | return da_mon;
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| 452 |
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| 453 | mon_storage = da_create_empty_storage(id);
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| 454 | if (!mon_storage)
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| 455 | return NULL;
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| 456 |
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| 457 | mon_storage->target = target;
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| 458 | return &mon_storage->rv.da_mon;
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| 459 | }
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| 460 |
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| 461 | |
| 462 | * __da_get_mon_storage - get the monitor storage from the hash table
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| 463 |
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| 464 | static inline struct da_monitor_storage *__da_get_mon_storage(da_id_type id)
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| 465 | {
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| 466 | struct da_monitor_storage *mon_storage;
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| 467 |
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| 468 | lockdep_assert_in_rcu_read_lock();
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| 469 | hash_for_each_possible_rcu(da_monitor_ht, mon_storage, node, id) {
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| 470 | if (mon_storage->id == id)
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| 471 | return mon_storage;
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| 472 | }
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| 473 |
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| 474 | return NULL;
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| 475 | }
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| 476 |
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| 477 | |
| 478 | * da_get_monitor - return the monitor for target
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| 479 |
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| 480 | static struct da_monitor *da_get_monitor(da_id_type id, monitor_target target)
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| 481 | {
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| 482 | struct da_monitor_storage *mon_storage;
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| 483 |
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| 484 | mon_storage = __da_get_mon_storage(id);
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| 485 | return mon_storage ? &mon_storage->rv.da_mon : NULL;
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| 486 | }
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| 487 |
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| 488 | |
| 489 | * da_get_target - return the object associated to the monitor
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| 490 |
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| 491 | static inline monitor_target da_get_target(struct da_monitor *da_mon)
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| 492 | {
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| 493 | return container_of(da_mon, struct da_monitor_storage, rv.da_mon)->target;
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| 494 | }
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| 495 |
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| 496 | |
| 497 | * da_get_id - return the id associated to the monitor
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| 498 |
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| 499 | static inline da_id_type da_get_id(struct da_monitor *da_mon)
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| 500 | {
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| 501 | return container_of(da_mon, struct da_monitor_storage, rv.da_mon)->id;
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| 502 | }
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| 503 |
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| 504 | |
| 505 | * da_create_or_get - create the per-object storage if not already there
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| 506 | *
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| 507 | * This needs a lookup so should be guarded by RCU, the condition is checked
|
| 508 | * directly in da_create_storage()
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| 509 |
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| 510 | static inline void da_create_or_get(da_id_type id, monitor_target target)
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| 511 | {
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| 512 | guard(rcu)();
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| 513 | da_create_storage(id, target, da_get_monitor(id, target));
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| 514 | }
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| 515 |
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| 516 | |
| 517 | * da_fill_empty_storage - store the target in a pre-allocated storage
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| 518 | *
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| 519 | * Can be used as a substitute of da_create_storage when starting a monitor in
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| 520 | * an environment where allocation is unsafe.
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| 521 |
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| 522 | static inline struct da_monitor *da_fill_empty_storage(da_id_type id,
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| 523 | monitor_target target,
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| 524 | struct da_monitor *da_mon)
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| 525 | {
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| 526 | if (unlikely(da_mon && !da_get_target(da_mon)))
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| 527 | container_of(da_mon, struct da_monitor_storage, rv.da_mon)->target = target;
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| 528 | return da_mon;
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| 529 | }
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| 530 |
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| 531 | |
| 532 | * da_get_target_by_id - return the object associated to the id
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| 533 |
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| 534 | static inline monitor_target da_get_target_by_id(da_id_type id)
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| 535 | {
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| 536 | struct da_monitor_storage *mon_storage;
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| 537 |
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| 538 | guard(rcu)();
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| 539 | mon_storage = __da_get_mon_storage(id);
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| 540 |
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| 541 | if (unlikely(!mon_storage))
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| 542 | return NULL;
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| 543 | return mon_storage->target;
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| 544 | }
|
| 545 |
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| 546 | |
| 547 | * da_destroy_storage - destroy the per-object storage
|
| 548 | *
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| 549 | * The caller is responsible to synchronise writers, either with locks or
|
| 550 | * implicitly. For instance, if da_destroy_storage is called at sched_exit and
|
| 551 | * da_create_storage can never occur after that, it's safe to call this without
|
| 552 | * locks.
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| 553 | * This function includes an RCU read-side critical section to synchronise
|
| 554 | * against da_monitor_destroy().
|
| 555 |
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| 556 | static inline void da_destroy_storage(da_id_type id)
|
| 557 | {
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| 558 | struct da_monitor_storage *mon_storage;
|
| 559 |
|
| 560 | guard(rcu)();
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| 561 | mon_storage = __da_get_mon_storage(id);
|
| 562 |
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| 563 | if (!mon_storage)
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| 564 | return;
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| 565 | da_monitor_reset_hook(&mon_storage->rv.da_mon);
|
| 566 | hash_del_rcu(&mon_storage->node);
|
| 567 | kfree_rcu(mon_storage, rcu);
|
| 568 | }
|
| 569 |
|
| 570 | static void __da_monitor_reset_all(void (*reset)(struct da_monitor *))
|
| 571 | {
|
| 572 | struct da_monitor_storage *mon_storage;
|
| 573 | int bkt;
|
| 574 |
|
| 575 | guard(rcu)();
|
| 576 | hash_for_each_rcu(da_monitor_ht, bkt, mon_storage, node)
|
| 577 | reset(&mon_storage->rv.da_mon);
|
| 578 | }
|
| 579 |
|
| 580 | static void da_monitor_reset_all(void)
|
| 581 | {
|
| 582 | __da_monitor_reset_all(da_monitor_reset);
|
| 583 | }
|
| 584 |
|
| 585 | static inline void da_monitor_reset_state_all(void)
|
| 586 | {
|
| 587 | __da_monitor_reset_all(da_monitor_reset_state);
|
| 588 | }
|
| 589 |
|
| 590 | static inline int da_monitor_init(void)
|
| 591 | {
|
| 592 | hash_init(da_monitor_ht);
|
| 593 | return 0;
|
| 594 | }
|
| 595 |
|
| 596 | static inline void da_monitor_destroy(void)
|
| 597 | {
|
| 598 | struct da_monitor_storage *mon_storage;
|
| 599 | struct hlist_node *tmp;
|
| 600 | int bkt;
|
| 601 |
|
| 602 | tracepoint_synchronize_unregister();
|
| 603 | da_monitor_reset_all();
|
| 604 | da_monitor_sync_hook();
|
| 605 | |
| 606 | * This function is called after all probes are disabled and no longer
|
| 607 | * pending, we can safely assume no concurrent user.
|
| 608 |
|
| 609 | hash_for_each_safe(da_monitor_ht, bkt, tmp, mon_storage, node) {
|
| 610 | hash_del_rcu(&mon_storage->node);
|
| 611 | kfree(mon_storage);
|
| 612 | }
|
| 613 | }
|
| 614 |
|
| 615 | |
| 616 | * Allow the per-object monitors to run allocation manually, necessary if the
|
| 617 | * start condition is in a context problematic for allocation (e.g. scheduling).
|
| 618 | * In such case, if the storage was pre-allocated without a target, set it now.
|
| 619 |
|
| 620 | #ifdef DA_SKIP_AUTO_ALLOC
|
| 621 | #define da_prepare_storage da_fill_empty_storage
|
| 622 | #else
|
| 623 | #define da_prepare_storage da_create_storage
|
| 624 | #endif
|
| 625 |
|
| 626 | #endif
|
| 627 |
|
| 628 | #if RV_MON_TYPE == RV_MON_GLOBAL || RV_MON_TYPE == RV_MON_PER_CPU
|
| 629 | |
| 630 | * Trace events for implicit monitors. Implicit monitor is the one which the
|
| 631 | * handler does not need to specify which da_monitor to manipulate. Examples
|
| 632 | * of implicit monitor are the per_cpu or the global ones.
|
| 633 |
|
| 634 |
|
| 635 | static inline void da_trace_event(struct da_monitor *da_mon,
|
| 636 | char *curr_state, char *event,
|
| 637 | char *next_state, bool is_final,
|
| 638 | da_id_type id)
|
| 639 | {
|
| 640 | CONCATENATE(trace_event_, MONITOR_NAME)(curr_state, event, next_state,
|
| 641 | is_final);
|
| 642 | }
|
| 643 |
|
| 644 | static inline void da_trace_error(struct da_monitor *da_mon,
|
| 645 | char *curr_state, char *event,
|
| 646 | da_id_type id)
|
| 647 | {
|
| 648 | CONCATENATE(trace_error_, MONITOR_NAME)(curr_state, event);
|
| 649 | }
|
| 650 |
|
| 651 | |
| 652 | * da_get_id - unused for implicit monitors
|
| 653 |
|
| 654 | static inline da_id_type da_get_id(struct da_monitor *da_mon)
|
| 655 | {
|
| 656 | return 0;
|
| 657 | }
|
| 658 |
|
| 659 | #elif RV_MON_TYPE == RV_MON_PER_TASK || RV_MON_TYPE == RV_MON_PER_OBJ
|
| 660 | |
| 661 | * Trace events for per_task/per_object monitors, report the target id.
|
| 662 |
|
| 663 |
|
| 664 | static inline void da_trace_event(struct da_monitor *da_mon,
|
| 665 | char *curr_state, char *event,
|
| 666 | char *next_state, bool is_final,
|
| 667 | da_id_type id)
|
| 668 | {
|
| 669 | CONCATENATE(trace_event_, MONITOR_NAME)(id, curr_state, event,
|
| 670 | next_state, is_final);
|
| 671 | }
|
| 672 |
|
| 673 | static inline void da_trace_error(struct da_monitor *da_mon,
|
| 674 | char *curr_state, char *event,
|
| 675 | da_id_type id)
|
| 676 | {
|
| 677 | CONCATENATE(trace_error_, MONITOR_NAME)(id, curr_state, event);
|
| 678 | }
|
| 679 | #endif
|
| 680 |
|
| 681 | |
| 682 | * da_event - handle an event for the da_mon
|
| 683 | *
|
| 684 | * This function is valid for both implicit and id monitors.
|
| 685 | * Retry in case there is a race between getting and setting the next state,
|
| 686 | * warn and reset the monitor if it runs out of retries. The monitor should be
|
| 687 | * able to handle various orders.
|
| 688 |
|
| 689 | static inline bool da_event(struct da_monitor *da_mon, enum events event, da_id_type id)
|
| 690 | {
|
| 691 | enum states curr_state, next_state;
|
| 692 |
|
| 693 | curr_state = READ_ONCE(da_mon->curr_state);
|
| 694 | for (int i = 0; i < MAX_DA_RETRY_RACING_EVENTS; i++) {
|
| 695 | next_state = model_get_next_state(curr_state, event);
|
| 696 | if (next_state == INVALID_STATE) {
|
| 697 | react(curr_state, event);
|
| 698 | da_trace_error(da_mon, model_get_state_name(curr_state),
|
| 699 | model_get_event_name(event), id);
|
| 700 | return false;
|
| 701 | }
|
| 702 | if (likely(try_cmpxchg(&da_mon->curr_state, &curr_state, next_state))) {
|
| 703 | if (!da_monitor_event_hook(da_mon, curr_state, event, next_state, id))
|
| 704 | return false;
|
| 705 | da_trace_event(da_mon, model_get_state_name(curr_state),
|
| 706 | model_get_event_name(event),
|
| 707 | model_get_state_name(next_state),
|
| 708 | model_is_final_state(next_state), id);
|
| 709 | return true;
|
| 710 | }
|
| 711 | }
|
| 712 |
|
| 713 | trace_rv_retries_error(__stringify(MONITOR_NAME), model_get_event_name(event));
|
| 714 | pr_warn("rv: " __stringify(MAX_DA_RETRY_RACING_EVENTS)
|
| 715 | " retries reached for event %s, resetting monitor %s",
|
| 716 | model_get_event_name(event), __stringify(MONITOR_NAME));
|
| 717 | return false;
|
| 718 | }
|
| 719 |
|
| 720 | static inline void __da_handle_event_common(struct da_monitor *da_mon,
|
| 721 | enum events event, da_id_type id)
|
| 722 | {
|
| 723 | if (!da_event(da_mon, event, id))
|
| 724 | da_monitor_reset(da_mon);
|
| 725 | }
|
| 726 |
|
| 727 | static inline void __da_handle_event(struct da_monitor *da_mon,
|
| 728 | enum events event, da_id_type id)
|
| 729 | {
|
| 730 | if (da_monitor_handling_event(da_mon))
|
| 731 | __da_handle_event_common(da_mon, event, id);
|
| 732 | }
|
| 733 |
|
| 734 | static inline bool __da_handle_start_event(struct da_monitor *da_mon,
|
| 735 | enum events event, da_id_type id)
|
| 736 | {
|
| 737 | if (!da_monitor_enabled())
|
| 738 | return 0;
|
| 739 | if (unlikely(!da_monitoring(da_mon))) {
|
| 740 | da_monitor_start(da_mon);
|
| 741 | return 0;
|
| 742 | }
|
| 743 |
|
| 744 | __da_handle_event_common(da_mon, event, id);
|
| 745 |
|
| 746 | return 1;
|
| 747 | }
|
| 748 |
|
| 749 | static inline bool __da_handle_start_run_event(struct da_monitor *da_mon,
|
| 750 | enum events event, da_id_type id)
|
| 751 | {
|
| 752 | if (!da_monitor_enabled())
|
| 753 | return 0;
|
| 754 | if (unlikely(!da_monitoring(da_mon)))
|
| 755 | da_monitor_start(da_mon);
|
| 756 |
|
| 757 | __da_handle_event_common(da_mon, event, id);
|
| 758 |
|
| 759 | return 1;
|
| 760 | }
|
| 761 |
|
| 762 | #if RV_MON_TYPE == RV_MON_GLOBAL || RV_MON_TYPE == RV_MON_PER_CPU
|
| 763 | |
| 764 | * Handle event for implicit monitor: da_get_monitor() will figure out
|
| 765 | * the monitor.
|
| 766 |
|
| 767 |
|
| 768 | |
| 769 | * da_handle_event - handle an event
|
| 770 |
|
| 771 | static inline void da_handle_event(enum events event)
|
| 772 | {
|
| 773 | da_implicit_guard();
|
| 774 | __da_handle_event(da_get_monitor(), event, 0);
|
| 775 | }
|
| 776 |
|
| 777 | |
| 778 | * da_handle_start_event - start monitoring or handle event
|
| 779 | *
|
| 780 | * This function is used to notify the monitor that the system is returning
|
| 781 | * to the initial state, so the monitor can start monitoring in the next event.
|
| 782 | * Thus:
|
| 783 | *
|
| 784 | * If the monitor already started, handle the event.
|
| 785 | * If the monitor did not start yet, start the monitor but skip the event.
|
| 786 |
|
| 787 | static inline bool da_handle_start_event(enum events event)
|
| 788 | {
|
| 789 | da_implicit_guard();
|
| 790 | return __da_handle_start_event(da_get_monitor(), event, 0);
|
| 791 | }
|
| 792 |
|
| 793 | |
| 794 | * da_handle_start_run_event - start monitoring and handle event
|
| 795 | *
|
| 796 | * This function is used to notify the monitor that the system is in the
|
| 797 | * initial state, so the monitor can start monitoring and handling event.
|
| 798 |
|
| 799 | static inline bool da_handle_start_run_event(enum events event)
|
| 800 | {
|
| 801 | da_implicit_guard();
|
| 802 | return __da_handle_start_run_event(da_get_monitor(), event, 0);
|
| 803 | }
|
| 804 |
|
| 805 | #elif RV_MON_TYPE == RV_MON_PER_TASK
|
| 806 | |
| 807 | * Handle event for per task.
|
| 808 |
|
| 809 |
|
| 810 | |
| 811 | * da_handle_event - handle an event
|
| 812 |
|
| 813 | static inline void da_handle_event(struct task_struct *tsk, enum events event)
|
| 814 | {
|
| 815 | __da_handle_event(da_get_monitor(tsk), event, tsk->pid);
|
| 816 | }
|
| 817 |
|
| 818 | |
| 819 | * da_handle_start_event - start monitoring or handle event
|
| 820 | *
|
| 821 | * This function is used to notify the monitor that the system is returning
|
| 822 | * to the initial state, so the monitor can start monitoring in the next event.
|
| 823 | * Thus:
|
| 824 | *
|
| 825 | * If the monitor already started, handle the event.
|
| 826 | * If the monitor did not start yet, start the monitor but skip the event.
|
| 827 |
|
| 828 | static inline bool da_handle_start_event(struct task_struct *tsk,
|
| 829 | enum events event)
|
| 830 | {
|
| 831 | return __da_handle_start_event(da_get_monitor(tsk), event, tsk->pid);
|
| 832 | }
|
| 833 |
|
| 834 | |
| 835 | * da_handle_start_run_event - start monitoring and handle event
|
| 836 | *
|
| 837 | * This function is used to notify the monitor that the system is in the
|
| 838 | * initial state, so the monitor can start monitoring and handling event.
|
| 839 |
|
| 840 | static inline bool da_handle_start_run_event(struct task_struct *tsk,
|
| 841 | enum events event)
|
| 842 | {
|
| 843 | return __da_handle_start_run_event(da_get_monitor(tsk), event, tsk->pid);
|
| 844 | }
|
| 845 |
|
| 846 | #elif RV_MON_TYPE == RV_MON_PER_OBJ
|
| 847 | |
| 848 | * Handle event for per object.
|
| 849 |
|
| 850 |
|
| 851 | |
| 852 | * da_handle_event - handle an event
|
| 853 |
|
| 854 | static inline void da_handle_event(da_id_type id, monitor_target target, enum events event)
|
| 855 | {
|
| 856 | struct da_monitor *da_mon;
|
| 857 |
|
| 858 | guard(rcu)();
|
| 859 | da_mon = da_get_monitor(id, target);
|
| 860 | if (likely(da_mon))
|
| 861 | __da_handle_event(da_mon, event, id);
|
| 862 | }
|
| 863 |
|
| 864 | |
| 865 | * da_handle_start_event - start monitoring or handle event
|
| 866 | *
|
| 867 | * This function is used to notify the monitor that the system is returning
|
| 868 | * to the initial state, so the monitor can start monitoring in the next event.
|
| 869 | * Thus:
|
| 870 | *
|
| 871 | * If the monitor already started, handle the event.
|
| 872 | * If the monitor did not start yet, start the monitor but skip the event.
|
| 873 |
|
| 874 | static inline bool da_handle_start_event(da_id_type id, monitor_target target,
|
| 875 | enum events event)
|
| 876 | {
|
| 877 | struct da_monitor *da_mon;
|
| 878 |
|
| 879 | guard(rcu)();
|
| 880 | da_mon = da_get_monitor(id, target);
|
| 881 | da_mon = da_prepare_storage(id, target, da_mon);
|
| 882 | if (unlikely(!da_mon))
|
| 883 | return 0;
|
| 884 | return __da_handle_start_event(da_mon, event, id);
|
| 885 | }
|
| 886 |
|
| 887 | |
| 888 | * da_handle_start_run_event - start monitoring and handle event
|
| 889 | *
|
| 890 | * This function is used to notify the monitor that the system is in the
|
| 891 | * initial state, so the monitor can start monitoring and handling event.
|
| 892 |
|
| 893 | static inline bool da_handle_start_run_event(da_id_type id, monitor_target target,
|
| 894 | enum events event)
|
| 895 | {
|
| 896 | struct da_monitor *da_mon;
|
| 897 |
|
| 898 | guard(rcu)();
|
| 899 | da_mon = da_get_monitor(id, target);
|
| 900 | da_mon = da_prepare_storage(id, target, da_mon);
|
| 901 | if (unlikely(!da_mon))
|
| 902 | return 0;
|
| 903 | return __da_handle_start_run_event(da_mon, event, id);
|
| 904 | }
|
| 905 |
|
| 906 | static inline void da_reset(da_id_type id, monitor_target target)
|
| 907 | {
|
| 908 | struct da_monitor *da_mon;
|
| 909 |
|
| 910 | guard(rcu)();
|
| 911 | da_mon = da_get_monitor(id, target);
|
| 912 | if (likely(da_mon))
|
| 913 | da_monitor_reset(da_mon);
|
| 914 | }
|
| 915 | #endif
|
| 916 |
|
| 917 | #if IS_ENABLED(CONFIG_RV_MONITORS_KUNIT_TEST)
|
| 918 | #if RV_MON_TYPE == RV_MON_PER_TASK
|
| 919 | #define RV_MON_OPS_INIT() { \
|
| 920 | .rv_this = &rv_this, \
|
| 921 | .is_per_task = true, \
|
| 922 | .task_slot = &task_mon_slot, \
|
| 923 | .task_reset = da_reset, \
|
| 924 | }
|
| 925 | #else
|
| 926 | #define RV_MON_OPS_INIT() { \
|
| 927 | .rv_this = &rv_this, \
|
| 928 | .monitor_init = da_monitor_init, \
|
| 929 | .monitor_destroy = da_monitor_destroy, \
|
| 930 | }
|
| 931 | #endif
|
| 932 | #endif
|
| 933 |
|
| 934 | #endif
|