From 2d396cb3b12641adcde91104a7c89994f2e876a6 Mon Sep 17 00:00:00 2001 From: "Steven Rostedt (VMware)" Date: Fri, 5 Feb 2021 18:04:39 -0500 Subject: tracing: Do not create "enable" or "filter" files for ftrace event subsystem The ftrace event subsystem is only created for showing the format files of events created by the ftrace tracers, and are not trace events. The ftrace subsystem currently has both the "enable" and "filter" files that in other subsystems are used to enable/disable all events within the subsystem or set a filter for all the subsystem events. As ftrace subsystem events do not use enable or filter operations, these files are useless in the ftrace subsystem. Remove them. Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_events.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) (limited to 'kernel/trace') diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 20ccce3e4ffb..c1e90611fe22 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -2097,16 +2097,20 @@ event_subsystem_dir(struct trace_array *tr, const char *name, dir->subsystem = system; file->system = dir; - entry = tracefs_create_file("filter", 0644, dir->entry, dir, - &ftrace_subsystem_filter_fops); - if (!entry) { - kfree(system->filter); - system->filter = NULL; - pr_warn("Could not create tracefs '%s/filter' entry\n", name); - } + /* the ftrace system is special, do not create enable or filter files */ + if (strcmp(name, "ftrace") != 0) { + + entry = tracefs_create_file("filter", 0644, dir->entry, dir, + &ftrace_subsystem_filter_fops); + if (!entry) { + kfree(system->filter); + system->filter = NULL; + pr_warn("Could not create tracefs '%s/filter' entry\n", name); + } - trace_create_file("enable", 0644, dir->entry, dir, - &ftrace_system_enable_fops); + trace_create_file("enable", 0644, dir->entry, dir, + &ftrace_system_enable_fops); + } list_add(&dir->list, &tr->systems); -- cgit v1.2.3