| Message ID | 20220113170059.82747-1-y.karadz@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2] libtracefs: New API for getting synthetic event | expand |
On Fri, Jan 14, 2022 at 10:17 AM Yordan Karadzhov (VMware) <y.karadz@gmail.com> wrote: > > A new API is proposed, to get tep event descriptor for given synthetic > event: > > tracefs_synth_get_event () > > The API implementation gets derived from the implementation of the > existing API tracefs_dynevent_get_event(). It can detect any newly > created or removed synthetic events. > > Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com> > --- > Documentation/libtracefs-synth2.txt | 13 +++++++++++-- > include/tracefs-local.h | 2 ++ > include/tracefs.h | 2 ++ > src/tracefs-dynevents.c | 17 +---------------- > src/tracefs-events.c | 21 +++++++++++++++++++++ > src/tracefs-hist.c | 18 ++++++++++++++++++ > 6 files changed, 55 insertions(+), 18 deletions(-) > > diff --git a/Documentation/libtracefs-synth2.txt b/Documentation/libtracefs-synth2.txt > index 8056ab8..444318c 100644 > --- a/Documentation/libtracefs-synth2.txt > +++ b/Documentation/libtracefs-synth2.txt > @@ -6,7 +6,8 @@ NAME > tracefs_synth_create, tracefs_synth_destroy, tracefs_synth_echo_cmd, tracefs_synth_complete, > tracefs_synth_get_start_hist, tracefs_synth_trace, tracefs_synth_snapshot, > tracefs_synth_get_name, tracefs_synth_raw_fmt, tracefs_synth_show_event, > -tracefs_synth_show_start_hist, tracefs_synth_show_end_hist - Creation of synthetic events > +tracefs_synth_show_start_hist, tracefs_synth_show_end_hist, tracefs_synth_get_event The new API should be added also in Documentation/libtracefs.txt, the main man page with all APIs. Forgot to mention that in the previous review. [ ... ]
On 14.01.22 г. 12:12 ч., Tzvetomir Stoyanov wrote: > On Fri, Jan 14, 2022 at 10:17 AM Yordan Karadzhov (VMware) > <y.karadz@gmail.com> wrote: >> >> A new API is proposed, to get tep event descriptor for given synthetic >> event: >> >> tracefs_synth_get_event () >> >> The API implementation gets derived from the implementation of the >> existing API tracefs_dynevent_get_event(). It can detect any newly >> created or removed synthetic events. >> >> Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com> >> --- >> Documentation/libtracefs-synth2.txt | 13 +++++++++++-- >> include/tracefs-local.h | 2 ++ >> include/tracefs.h | 2 ++ >> src/tracefs-dynevents.c | 17 +---------------- >> src/tracefs-events.c | 21 +++++++++++++++++++++ >> src/tracefs-hist.c | 18 ++++++++++++++++++ >> 6 files changed, 55 insertions(+), 18 deletions(-) >> >> diff --git a/Documentation/libtracefs-synth2.txt b/Documentation/libtracefs-synth2.txt >> index 8056ab8..444318c 100644 >> --- a/Documentation/libtracefs-synth2.txt >> +++ b/Documentation/libtracefs-synth2.txt >> @@ -6,7 +6,8 @@ NAME >> tracefs_synth_create, tracefs_synth_destroy, tracefs_synth_echo_cmd, tracefs_synth_complete, >> tracefs_synth_get_start_hist, tracefs_synth_trace, tracefs_synth_snapshot, >> tracefs_synth_get_name, tracefs_synth_raw_fmt, tracefs_synth_show_event, >> -tracefs_synth_show_start_hist, tracefs_synth_show_end_hist - Creation of synthetic events >> +tracefs_synth_show_start_hist, tracefs_synth_show_end_hist, tracefs_synth_get_event > > The new API should be added also in Documentation/libtracefs.txt, the > main man page with all APIs. Forgot to mention that in the previous > review. > Hmm, I see absolutely no tracefs_synth_*() APIs in Documentation/libtracefs.txt. Maybe this can be fixed in a separate patch. thanks, Yordan > [ ... ] > >
On Fri, Jan 14, 2022 at 4:58 PM Yordan Karadzhov <y.karadz@gmail.com> wrote: > > > > On 14.01.22 г. 12:12 ч., Tzvetomir Stoyanov wrote: > > On Fri, Jan 14, 2022 at 10:17 AM Yordan Karadzhov (VMware) > > <y.karadz@gmail.com> wrote: > >> > >> A new API is proposed, to get tep event descriptor for given synthetic > >> event: > >> > >> tracefs_synth_get_event () > >> > >> The API implementation gets derived from the implementation of the > >> existing API tracefs_dynevent_get_event(). It can detect any newly > >> created or removed synthetic events. > >> > >> Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com> > >> --- > >> Documentation/libtracefs-synth2.txt | 13 +++++++++++-- > >> include/tracefs-local.h | 2 ++ > >> include/tracefs.h | 2 ++ > >> src/tracefs-dynevents.c | 17 +---------------- > >> src/tracefs-events.c | 21 +++++++++++++++++++++ > >> src/tracefs-hist.c | 18 ++++++++++++++++++ > >> 6 files changed, 55 insertions(+), 18 deletions(-) > >> > >> diff --git a/Documentation/libtracefs-synth2.txt b/Documentation/libtracefs-synth2.txt > >> index 8056ab8..444318c 100644 > >> --- a/Documentation/libtracefs-synth2.txt > >> +++ b/Documentation/libtracefs-synth2.txt > >> @@ -6,7 +6,8 @@ NAME > >> tracefs_synth_create, tracefs_synth_destroy, tracefs_synth_echo_cmd, tracefs_synth_complete, > >> tracefs_synth_get_start_hist, tracefs_synth_trace, tracefs_synth_snapshot, > >> tracefs_synth_get_name, tracefs_synth_raw_fmt, tracefs_synth_show_event, > >> -tracefs_synth_show_start_hist, tracefs_synth_show_end_hist - Creation of synthetic events > >> +tracefs_synth_show_start_hist, tracefs_synth_show_end_hist, tracefs_synth_get_event > > > > The new API should be added also in Documentation/libtracefs.txt, the > > main man page with all APIs. Forgot to mention that in the previous > > review. > > > > Hmm, I see absolutely no tracefs_synth_*() APIs in Documentation/libtracefs.txt. > Maybe this can be fixed in a separate patch. > Yes, the whole synth_* section is missing, so I submitted a patch to update that list. We can add tracefs_synth_get_event() later, when it is accepted. > thanks, > Yordan > > > > > [ ... ] > > > >
diff --git a/Documentation/libtracefs-synth2.txt b/Documentation/libtracefs-synth2.txt index 8056ab8..444318c 100644 --- a/Documentation/libtracefs-synth2.txt +++ b/Documentation/libtracefs-synth2.txt @@ -6,7 +6,8 @@ NAME tracefs_synth_create, tracefs_synth_destroy, tracefs_synth_echo_cmd, tracefs_synth_complete, tracefs_synth_get_start_hist, tracefs_synth_trace, tracefs_synth_snapshot, tracefs_synth_get_name, tracefs_synth_raw_fmt, tracefs_synth_show_event, -tracefs_synth_show_start_hist, tracefs_synth_show_end_hist - Creation of synthetic events +tracefs_synth_show_start_hist, tracefs_synth_show_end_hist, tracefs_synth_get_event +- Creation of synthetic events SYNOPSIS -------- @@ -32,7 +33,7 @@ int tracefs_synth_raw_fmt(struct trace_seq pass:[*]seq, struct tracefs_synth pas const char *tracefs_synth_show_event(struct tracefs_synth pass:[*]synth); const char *tracefs_synth_show_start_hist(struct tracefs_synth pass:[*]synth); const char *tracefs_synth_show_end_hist(struct tracefs_synth pass:[*]synth); - +struct tep_event pass:[*]*tracefs_synth_get_event*(struct tep_handle pass:[*]_tep_, struct tracefs_synth pass:[*]_synth_); -- DESCRIPTION @@ -114,11 +115,19 @@ and is freed with the event by *tracefs_synth_free*(). synthetic event or NULL on error. The returned string belongs to the synth event object and is freed with the event by *tracefs_synth_free*(). +The *tracefs_synth_get_event*() function returns a tep event, describing the given synthetic +event. The API detects any newly created or removed dynamic events. The returned pointer to +tep event is controlled by @tep and must not be freed. + RETURN VALUE ------------ *tracefs_synth_get_name*(), *tracefs_synth_show_event*(), *tracefs_synth_show_start_hist*() and *tracefs_synth_show_end_hist*() return a string owned by the synth event object. +The *tracefs_synth_get_event*() function returns a pointer to a tep event or NULL in case of an +error or if the requested synthetic event is missing. The returned pointer to tep event is +controlled by @tep and must not be freed. + All other functions return zero on success or -1 on error. ERRORS diff --git a/include/tracefs-local.h b/include/tracefs-local.h index daea5da..bf157e1 100644 --- a/include/tracefs-local.h +++ b/include/tracefs-local.h @@ -116,5 +116,7 @@ int trace_load_events(struct tep_handle *tep, const char *tracing_dir, const char *system); int trace_rescan_events(struct tep_handle *tep, const char *tracing_dir, const char *system); +struct tep_event *get_tep_event(struct tep_handle *tep, + const char *system, const char *name); #endif /* _TRACE_FS_LOCAL_H */ diff --git a/include/tracefs.h b/include/tracefs.h index bd758dc..9c53b84 100644 --- a/include/tracefs.h +++ b/include/tracefs.h @@ -564,5 +564,7 @@ const char *tracefs_synth_show_end_hist(struct tracefs_synth *synth); struct tracefs_synth *tracefs_sql(struct tep_handle *tep, const char *name, const char *sql_buffer, char **err); +struct tep_event * +tracefs_synth_get_event(struct tep_handle *tep, struct tracefs_synth *synth); #endif /* _TRACE_FS_H */ diff --git a/src/tracefs-dynevents.c b/src/tracefs-dynevents.c index d089d02..ddebb6b 100644 --- a/src/tracefs-dynevents.c +++ b/src/tracefs-dynevents.c @@ -765,23 +765,8 @@ error: struct tep_event * tracefs_dynevent_get_event(struct tep_handle *tep, struct tracefs_dynevent *dynevent) { - struct tep_event *event; - if (!tep || !dynevent || !dynevent->event) return NULL; - /* Check if event exists in the system */ - if (!tracefs_event_file_exists(NULL, dynevent->system, dynevent->event, "format")) - return NULL; - - /* If the dynamic event is already loaded in the tep, return it */ - event = tep_find_event_by_name(tep, dynevent->system, dynevent->event); - if (event) - return event; - - /* Try to load any new events from the given system */ - if (trace_rescan_events(tep, NULL, dynevent->system)) - return NULL; - - return tep_find_event_by_name(tep, dynevent->system, dynevent->event); + return get_tep_event(tep, dynevent->system, dynevent->event); } diff --git a/src/tracefs-events.c b/src/tracefs-events.c index 067f6e0..30e80ce 100644 --- a/src/tracefs-events.c +++ b/src/tracefs-events.c @@ -752,6 +752,27 @@ __hidden int trace_load_events(struct tep_handle *tep, return load_events(tep, tracing_dir, system, false); } +__hidden struct tep_event *get_tep_event(struct tep_handle *tep, + const char *system, const char *name) +{ + struct tep_event *event; + + /* Check if event exists in the system */ + if (!tracefs_event_file_exists(NULL, system, name, "format")) + return NULL; + + /* If the dynamic event is already loaded in the tep, return it */ + event = tep_find_event_by_name(tep, system, name); + if (event) + return event; + + /* Try to load any new events from the given system */ + if (trace_rescan_events(tep, NULL, system)) + return NULL; + + return tep_find_event_by_name(tep, system, name); +} + static int read_header(struct tep_handle *tep, const char *tracing_dir) { struct stat st; diff --git a/src/tracefs-hist.c b/src/tracefs-hist.c index 7146fc1..8d99492 100644 --- a/src/tracefs-hist.c +++ b/src/tracefs-hist.c @@ -2197,3 +2197,21 @@ int tracefs_synth_echo_cmd(struct trace_seq *seq, } return ret; } + +/** + * tracefs_synth_get_event - return tep event representing the given synthetic event + * @tep: a handle to the trace event parser context that holds the events + * @synth: a synthetic event context, describing given synthetic event. + * + * Returns a pointer to a tep event describing the given synthetic event. The pointer + * is managed by the @tep handle and must not be freed. In case of an error, or in case + * the requested synthetic event is missing in the @tep handler - NULL is returned. + */ +struct tep_event * +tracefs_synth_get_event(struct tep_handle *tep, struct tracefs_synth *synth) +{ + if (!tep || !synth || !synth->name) + return NULL; + + return get_tep_event(tep, SYNTHETIC_GROUP, synth->name); +}
A new API is proposed, to get tep event descriptor for given synthetic event: tracefs_synth_get_event () The API implementation gets derived from the implementation of the existing API tracefs_dynevent_get_event(). It can detect any newly created or removed synthetic events. Signed-off-by: Yordan Karadzhov (VMware) <y.karadz@gmail.com> --- Documentation/libtracefs-synth2.txt | 13 +++++++++++-- include/tracefs-local.h | 2 ++ include/tracefs.h | 2 ++ src/tracefs-dynevents.c | 17 +---------------- src/tracefs-events.c | 21 +++++++++++++++++++++ src/tracefs-hist.c | 18 ++++++++++++++++++ 6 files changed, 55 insertions(+), 18 deletions(-)