diff options
Diffstat (limited to 'Documentation/libtracefs-events.txt')
| -rw-r--r-- | Documentation/libtracefs-events.txt | 57 |
1 files changed, 29 insertions, 28 deletions
diff --git a/Documentation/libtracefs-events.txt b/Documentation/libtracefs-events.txt index f998c79..90c54b8 100644 --- a/Documentation/libtracefs-events.txt +++ b/Documentation/libtracefs-events.txt @@ -4,7 +4,7 @@ libtracefs(3) NAME ---- tracefs_event_systems, tracefs_system_events, tracefs_event_enable, tracefs_event_disable, -tracefs_iterate_raw_events, tracefs_iterate_stop - Work with trace systems and events. +tracefs_event_is_enabled - Work with trace systems and events. SYNOPSIS -------- @@ -12,18 +12,21 @@ SYNOPSIS -- *#include <tracefs.h>* +enum tracefs_event_state { + TRACEFS_ERROR = -1, + TRACEFS_ALL_DISABLED = 0, + TRACEFS_ALL_ENABLED = 1, + TRACEFS_SOME_ENABLED = 2, +}; + char pass:[*]pass:[*]*tracefs_event_systems*(const char pass:[*]_tracing_dir_); char pass:[*]pass:[*]*tracefs_system_events*(const char pass:[*]_tracing_dir_, const char pass:[*]_system_); int *tracefs_event_enable*(struct tracefs_instance pass:[*]_instance_, const char pass:[*]_system_, const char pass:[*]_event_); int *tracefs_event_disable*(struct tracefs_instance pass:[*]_instance_, const char pass:[*]_system_, const char pass:[*]_event_); -int *tracefs_iterate_raw_events*(struct tep_handle pass:[*]_tep_, struct tracefs_instance pass:[*]_instance_, - cpu_set_t pass:[*]_cpus_, int _cpu_size_, - int (pass:[*]_callback_)(struct tep_event pass:[*], struct tep_record pass:[*], int, void pass:[*]), - void pass:[*]_callback_context_); -void *tracefs_iterate_stop*(struct tracefs_instance pass:[*]_instance_); - +enum tracefs_enable_state *tracefs_event_is_enabled*(struct tracefs_instance pass:[*]_instance_, + const char pass:[*]_system_, const char pass:[*]_event_); -- DESCRIPTION @@ -61,25 +64,23 @@ events. That is, if _instance_ is NULL, then the top level tracing directory is used. If both _system_ and _event_ are NULL then all events are disabled for the given _instance_, and so on. -The *tracefs_iterate_raw_events()* function will read the tracefs raw -data buffers and call the specified _callback_ function for every event it -encounters. Events are iterated in sorted order: oldest first. An initialized -_tep_ handler is required (See *tracefs_local_events*(3)). If _instance_ is -NULL, then the toplevel tracefs buffer is used, otherwise the buffer for -the corresponding _instance_ is read. To filter only on a subset of CPUs, -_cpus_ and _cpu_size_ may be set to only call _callback_ with events that -occurred on the CPUs specified, otherwise if _cpus_ is NULL then the _callback_ -function will be called for all events, and _cpu_size_ is ignored. The -_callback_ function will be called with the following parameters: A -pointer to a struct tep_event that corresponds to the type of event the -record is; The record representing the event; The CPU that the event -occurred on; and a pointer to user specified _callback_context_. If the _callback_ -returns non-zero, the iteration stops. - -Use *tracefs_iterate_stop()* to force a executing *tracefs_iterate_raw_events()* -to halt. This can be called from either a callback that is called by -the iterator (even though a return of non-zero will stop it), or from another -thread. +The *tracefs_event_is_enabled()* returns if an event is enabled, a set of +events are enabled, a system is enabled, or all events are enabled. If both +_system_ and _event_ are NULL, then it returns the enable state of all events. +If _system_ is not NULL and _event_ is NULL, then it will check if all the events +in all the systems that _system_ and return the enable state of those events. +If _system_ is NULL and _event_ is not NULL, then it will match all the events +in all systems that match _event_ and return their enabled state. If both _system_ +and _event_ are not NULL, then it will return the enabled state of all matching +events. The enabled state is defined as: + +*TRACEFS_ERROR* - An error occurred including no event were matched. + +*TRACEFS_ALL_DISABLED* - All matching events are disabled. + +*TRACEFS_ALL_ENABLED* - All matching events are enabled. + +*TRACEFS_SOME_ENABLED* - Some matching events were enabled while others were not. RETURN VALUE ------------ @@ -95,8 +96,8 @@ found, it will return -1 and errno will be set. If no errors occur, but no event are found that match the _system_ and _event_ parameters, then -1 is returned and errno is not set. -The *tracefs_iterate_raw_events()* function returns -1 in case of an error or -0 otherwise. +The *tracefs_event_is_enabled()* returns the enabled status of the matching events +or TRACEFS_ERROR on error. EXAMPLE ------- |