Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 | /* SPDX-License-Identifier: GPL-2.0 */ /* * Common header file for generic dynamic events. */ #ifndef _TRACE_DYNEVENT_H #define _TRACE_DYNEVENT_H #include <linux/kernel.h> #include <linux/list.h> #include <linux/mutex.h> #include <linux/seq_file.h> #include "trace.h" struct dyn_event; /** * struct dyn_event_operations - Methods for each type of dynamic events * * These methods must be set for each type, since there is no default method. * Before using this for dyn_event_init(), it must be registered by * dyn_event_register(). * * @create: Parse and create event method. This is invoked when user passes * a event definition to dynamic_events interface. This must not destruct * the arguments and return -ECANCELED if given arguments doesn't match its * command prefix. * @show: Showing method. This is invoked when user reads the event definitions * via dynamic_events interface. * @is_busy: Check whether given event is busy so that it can not be deleted. * Return true if it is busy, otherwides false. * @free: Delete the given event. Return 0 if success, otherwides error. * @match: Check whether given event and system name match this event. * Return true if it matches, otherwides false. * * Except for @create, these methods are called under holding event_mutex. */ struct dyn_event_operations { struct list_head list; int (*create)(int argc, const char *argv[]); int (*show)(struct seq_file *m, struct dyn_event *ev); bool (*is_busy)(struct dyn_event *ev); int (*free)(struct dyn_event *ev); bool (*match)(const char *system, const char *event, struct dyn_event *ev); }; /* Register new dyn_event type -- must be called at first */ int dyn_event_register(struct dyn_event_operations *ops); /** * struct dyn_event - Dynamic event list header * * The dyn_event structure encapsulates a list and a pointer to the operators * for making a global list of dynamic events. * User must includes this in each event structure, so that those events can * be added/removed via dynamic_events interface. */ struct dyn_event { struct list_head list; struct dyn_event_operations *ops; }; extern struct list_head dyn_event_list; static inline int dyn_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) { if (!ev || !ops) return -EINVAL; INIT_LIST_HEAD(&ev->list); ev->ops = ops; return 0; } static inline int dyn_event_add(struct dyn_event *ev) { lockdep_assert_held(&event_mutex); if (!ev || !ev->ops) return -EINVAL; list_add_tail(&ev->list, &dyn_event_list); return 0; } static inline void dyn_event_remove(struct dyn_event *ev) { lockdep_assert_held(&event_mutex); list_del_init(&ev->list); } void *dyn_event_seq_start(struct seq_file *m, loff_t *pos); void *dyn_event_seq_next(struct seq_file *m, void *v, loff_t *pos); void dyn_event_seq_stop(struct seq_file *m, void *v); int dyn_events_release_all(struct dyn_event_operations *type); int dyn_event_release(int argc, char **argv, struct dyn_event_operations *type); /* * for_each_dyn_event - iterate over the dyn_event list * @pos: the struct dyn_event * to use as a loop cursor * * This is just a basement of for_each macro. Wrap this for * each actual event structure with ops filtering. */ #define for_each_dyn_event(pos) \ list_for_each_entry(pos, &dyn_event_list, list) /* * for_each_dyn_event - iterate over the dyn_event list safely * @pos: the struct dyn_event * to use as a loop cursor * @n: the struct dyn_event * to use as temporary storage */ #define for_each_dyn_event_safe(pos, n) \ list_for_each_entry_safe(pos, n, &dyn_event_list, list) #endif |