Commit d4df54f3 authored by Masami Hiramatsu (Google)'s avatar Masami Hiramatsu (Google)
Browse files

tracepoint: Support iterating tracepoints in a loading module 

Add for_each_tracepoint_in_module() function to iterate tracepoints in
a module. This API is needed for handling tracepoints in a loading
module from tracepoint_module_notifier callback function.
This also update for_each_module_tracepoint() to pass the module to
callback function so that it can find module easily.

Link: https://lore.kernel.org/all/172397778740.286558.15781131277732977643.stgit@devnote2/



Signed-off-by: default avatarMasami Hiramatsu (Google) <mhiramat@kernel.org>
parent d5dbf8b4

include/linux/tracepoint.h

+15 −2
Original line number Diff line number Diff line
@@ -64,7 +64,12 @@ struct tp_module { 
bool trace_module_has_bad_taint(struct module *mod);

extern int register_tracepoint_module_notifier(struct notifier_block *nb);

extern int unregister_tracepoint_module_notifier(struct notifier_block *nb);

void for_each_module_tracepoint(void (*fct)(struct tracepoint *, void *),

void for_each_module_tracepoint(void (*fct)(struct tracepoint *,

					struct module *, void *),

				void *priv);

void for_each_tracepoint_in_module(struct module *,

				   void (*fct)(struct tracepoint *,

					struct module *, void *),

				   void *priv);

#else

static inline bool trace_module_has_bad_taint(struct module *mod)
@@ -82,7 +87,15 @@ int unregister_tracepoint_module_notifier(struct notifier_block *nb) 
	return 0;

}

static inline

void for_each_module_tracepoint(void (*fct)(struct tracepoint *, void *),

void for_each_module_tracepoint(void (*fct)(struct tracepoint *,

					struct module *, void *),

				void *priv)

{

}

static inline

void for_each_tracepoint_in_module(struct module *mod,

				   void (*fct)(struct tracepoint *,

					struct module *, void *),

				   void *priv)

{

}

kernel/tracepoint.c

+29 −8
Original line number Diff line number Diff line
@@ -736,24 +736,45 @@ static __init int init_tracepoints(void) 
}

__initcall(init_tracepoints);



/**

 * for_each_tracepoint_in_module - iteration on all tracepoints in a module

 * @mod: module

 * @fct: callback

 * @priv: private data

 */

void for_each_tracepoint_in_module(struct module *mod,

				   void (*fct)(struct tracepoint *tp,

				    struct module *mod, void *priv),

				   void *priv)

{

	tracepoint_ptr_t *begin, *end, *iter;



	lockdep_assert_held(&tracepoint_module_list_mutex);



	if (!mod)

		return;



	begin = mod->tracepoints_ptrs;

	end = mod->tracepoints_ptrs + mod->num_tracepoints;



	for (iter = begin; iter < end; iter++)

		fct(tracepoint_ptr_deref(iter), mod, priv);

}



/**

 * for_each_module_tracepoint - iteration on all tracepoints in all modules

 * @fct: callback

 * @priv: private data

 */

void for_each_module_tracepoint(void (*fct)(struct tracepoint *tp, void *priv),

void for_each_module_tracepoint(void (*fct)(struct tracepoint *tp,

				 struct module *mod, void *priv),

				void *priv)

{

	struct tp_module *tp_mod;

	struct module *mod;



	mutex_lock(&tracepoint_module_list_mutex);

	list_for_each_entry(tp_mod, &tracepoint_module_list, list) {

		mod = tp_mod->mod;

		for_each_tracepoint_range(mod->tracepoints_ptrs,

			mod->tracepoints_ptrs + mod->num_tracepoints,

			fct, priv);

	}

	list_for_each_entry(tp_mod, &tracepoint_module_list, list)

		for_each_tracepoint_in_module(tp_mod->mod, fct, priv);

	mutex_unlock(&tracepoint_module_list_mutex);

}

#endif /* CONFIG_MODULES */