From f744bd576a827c5b02e756b81fc2578edf8179b8 Mon Sep 17 00:00:00 2001 From: Jason Baron Date: Mon, 10 Aug 2009 16:52:39 -0400 Subject: [PATCH] tracing: Raw_init() bailout in trace event register fail case Allow the return value of raw_init() trace event callback to bail us out of creating a trace event file, in case we fail to register our event. Also, we plan to return -ENOSYS for syscall events that don't match any syscalls listed in our arch tracing syscall table, we don't want to warn in that case, we just want this event to be invisible in debugfs and ignored. Signed-off-by: Jason Baron Cc: Lai Jiangshan Cc: Steven Rostedt Cc: Peter Zijlstra Cc: Mathieu Desnoyers Cc: Jiaying Zhang Cc: Martin Bligh Cc: Li Zefan Cc: Masami Hiramatsu Signed-off-by: Frederic Weisbecker --- kernel/trace/trace_events.c | 29 +++++++++++++++++++---------- 1 file changed, 19 insertions(+), 10 deletions(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index e0cbede96783..f95f8470dd38 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -925,15 +925,6 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events, if (strcmp(call->system, TRACE_SYSTEM) != 0) d_events = event_subsystem_dir(call->system, d_events); - if (call->raw_init) { - ret = call->raw_init(); - if (ret < 0) { - pr_warning("Could not initialize trace point" - " events/%s\n", call->name); - return ret; - } - } - call->dir = debugfs_create_dir(call->name, d_events); if (!call->dir) { pr_warning("Could not create debugfs " @@ -1058,6 +1049,7 @@ static void trace_module_add_events(struct module *mod) struct ftrace_module_file_ops *file_ops = NULL; struct ftrace_event_call *call, *start, *end; struct dentry *d_events; + int ret; start = mod->trace_events; end = mod->trace_events + mod->num_trace_events; @@ -1073,7 +1065,15 @@ static void trace_module_add_events(struct module *mod) /* The linker may leave blanks */ if (!call->name) continue; - + if (call->raw_init) { + ret = call->raw_init(); + if (ret < 0) { + if (ret != -ENOSYS) + pr_warning("Could not initialize trace " + "point events/%s\n", call->name); + continue; + } + } /* * This module has events, create file ops for this module * if not already done. @@ -1225,6 +1225,15 @@ static __init int event_trace_init(void) /* The linker may leave blanks */ if (!call->name) continue; + if (call->raw_init) { + ret = call->raw_init(); + if (ret < 0) { + if (ret != -ENOSYS) + pr_warning("Could not initialize trace " + "point events/%s\n", call->name); + continue; + } + } list_add(&call->list, &ftrace_events); event_create_dir(call, d_events, &ftrace_event_id_fops, &ftrace_enable_fops, &ftrace_event_filter_fops, -- 2.20.1