From 1ce25e9f6fff7633955e8ce776e5e9d7a780d34b Mon Sep 17 00:00:00 2001 From: Masami Hiramatsu Date: Mon, 5 Nov 2018 18:04:57 +0900 Subject: [PATCH] tracing: Add generic event-name based remove event method Add a generic method to remove event from dynamic event list. This is same as other system under ftrace. You just need to pass the event name with '!', e.g. # echo p:new_grp/new_event _do_fork > dynamic_events This creates an event, and # echo '!p:new_grp/new_event _do_fork' > dynamic_events Or, # echo '!p:new_grp/new_event' > dynamic_events will remove new_grp/new_event event. Note that this doesn't check the event prefix (e.g. "p:") strictly, because the "group/event" name must be unique. Link: http://lkml.kernel.org/r/154140869774.17322.8887303560398645347.stgit@devbox Reviewed-by: Tom Zanussi Tested-by: Tom Zanussi Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace_dynevent.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/kernel/trace/trace_dynevent.c b/kernel/trace/trace_dynevent.c index f17a887abb66..dd1f43588d70 100644 --- a/kernel/trace/trace_dynevent.c +++ b/kernel/trace/trace_dynevent.c @@ -37,10 +37,17 @@ int dyn_event_release(int argc, char **argv, struct dyn_event_operations *type) char *system = NULL, *event, *p; int ret = -ENOENT; - if (argv[0][1] != ':') - return -EINVAL; + if (argv[0][0] == '-') { + if (argv[0][1] != ':') + return -EINVAL; + event = &argv[0][2]; + } else { + event = strchr(argv[0], ':'); + if (!event) + return -EINVAL; + event++; + } - event = &argv[0][2]; p = strchr(event, '/'); if (p) { system = event; @@ -69,7 +76,7 @@ static int create_dyn_event(int argc, char **argv) struct dyn_event_operations *ops; int ret; - if (argv[0][0] == '-') + if (argv[0][0] == '-' || argv[0][0] == '!') return dyn_event_release(argc, argv, NULL); mutex_lock(&dyn_event_ops_mutex);