From 3c96529c0739959e2aa235d44e47f5c68c1e40de Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Tue, 8 May 2018 15:06:38 -0400 Subject: [PATCH] tracing: Add __find_event_file() to find event files without restrictions By adding the function __find_event_file() that can search for files without restrictions, such as if the event associated with the file has a reg function, or if it has the "ignore" flag set, the files that are associated to ftrace internal events (like trace_marker and function events) can be found and used. find_event_file() still returns a "filtered" file, as most callers need a valid trace event file. One created by the trace_events.h macros and not one created for parsing ftrace specific events. Reviewed-by: Namhyung Kim Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.h | 3 +++ kernel/trace/trace_events.c | 22 +++++++++++++++++----- 2 files changed, 20 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 6bfc246..07c4396 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -1454,6 +1454,9 @@ extern void trace_event_enable_tgid_record(bool enable); extern int event_trace_add_tracer(struct dentry *parent, struct trace_array *tr); extern int event_trace_del_tracer(struct trace_array *tr); +extern struct trace_event_file *__find_event_file(struct trace_array *tr, + const char *system, + const char *event); extern struct trace_event_file *find_event_file(struct trace_array *tr, const char *system, const char *event); diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 05c7172..caf7635 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2473,8 +2473,9 @@ __trace_add_event_dirs(struct trace_array *tr) } } +/* Returns any file that matches the system and event */ struct trace_event_file * -find_event_file(struct trace_array *tr, const char *system, const char *event) +__find_event_file(struct trace_array *tr, const char *system, const char *event) { struct trace_event_file *file; struct trace_event_call *call; @@ -2485,10 +2486,7 @@ find_event_file(struct trace_array *tr, const char *system, const char *event) call = file->event_call; name = trace_event_name(call); - if (!name || !call->class || !call->class->reg) - continue; - - if (call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) + if (!name || !call->class) continue; if (strcmp(event, name) == 0 && @@ -2498,6 +2496,20 @@ find_event_file(struct trace_array *tr, const char *system, const char *event) return NULL; } +/* Returns valid trace event files that match system and event */ +struct trace_event_file * +find_event_file(struct trace_array *tr, const char *system, const char *event) +{ + struct trace_event_file *file; + + file = __find_event_file(tr, system, event); + if (!file || !file->event_call->class->reg || + file->event_call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) + return NULL; + + return file; +} + #ifdef CONFIG_DYNAMIC_FTRACE /* Avoid typos */ -- 2.7.4