| Message ID | 20210817035026.936958254@goodmis.org (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | tracing: Creation of event probe | expand |
On Mon, 16 Aug 2021 23:42:56 -0400 Steven Rostedt <rostedt@goodmis.org> wrote: > From: "Steven Rostedt (VMware)" <rostedt@goodmis.org> > > To differentiate between static and dynamic events, add a new flag > DYNAMIC to the event flags that all dynamic events have set. This will > allow to differentiate when attaching to a dynamic event from a static > event. > > Static events have a mod pointer that references the module they were > created in (or NULL for core kernel). This can be incremented when the > event has something attached to it. But there exists no such mechanism for > dynamic events. This is dangerous as the dynamic events may now disappear > without the "attachment" knowing that it no longer exists. > > To enforce the dynamic flag, change dyn_event_add() to pass the event that > is being created such that it can set the DYNAMIC flag of the event. This > helps make sure that no location that creates a dynamic event misses > setting this flag. > > Link: https://lore.kernel.org/linux-trace-devel/20210813004448.51c7de69ce432d338f4d226b@kernel.org/ > This looks good to me. Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Thank you, > Suggested-by: Masami Hiramatsu <mhiramat@kernel.org> > Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> > --- > include/linux/trace_events.h | 3 +++ > kernel/trace/trace_dynevent.h | 4 +++- > kernel/trace/trace_events_synth.c | 2 +- > kernel/trace/trace_kprobe.c | 4 ++-- > kernel/trace/trace_uprobe.c | 4 ++-- > 5 files changed, 11 insertions(+), 6 deletions(-) > > diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h > index ad413b382a3c..53c9dffd87fd 100644 > --- a/include/linux/trace_events.h > +++ b/include/linux/trace_events.h > @@ -310,6 +310,7 @@ enum { > TRACE_EVENT_FL_NO_SET_FILTER_BIT, > TRACE_EVENT_FL_IGNORE_ENABLE_BIT, > TRACE_EVENT_FL_TRACEPOINT_BIT, > + TRACE_EVENT_FL_DYNAMIC_BIT, > TRACE_EVENT_FL_KPROBE_BIT, > TRACE_EVENT_FL_UPROBE_BIT, > }; > @@ -321,6 +322,7 @@ enum { > * NO_SET_FILTER - Set when filter has error and is to be ignored > * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file > * TRACEPOINT - Event is a tracepoint > + * DYNAMIC - Event is a dynamic event (created at run time) > * KPROBE - Event is a kprobe > * UPROBE - Event is a uprobe > */ > @@ -330,6 +332,7 @@ enum { > TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), > TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), > TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), > + TRACE_EVENT_FL_DYNAMIC = (1 << TRACE_EVENT_FL_DYNAMIC_BIT), > TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), > TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), > }; > diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h > index 7754936b57ee..936477a111d3 100644 > --- a/kernel/trace/trace_dynevent.h > +++ b/kernel/trace/trace_dynevent.h > @@ -76,13 +76,15 @@ int dyn_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) > return 0; > } > > -static inline int dyn_event_add(struct dyn_event *ev) > +static inline int dyn_event_add(struct dyn_event *ev, > + struct trace_event_call *call) > { > lockdep_assert_held(&event_mutex); > > if (!ev || !ev->ops) > return -EINVAL; > > + call->flags |= TRACE_EVENT_FL_DYNAMIC; > list_add_tail(&ev->list, &dyn_event_list); > return 0; > } > diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c > index 9315fc03e303..f4f5489e1e28 100644 > --- a/kernel/trace/trace_events_synth.c > +++ b/kernel/trace/trace_events_synth.c > @@ -1298,7 +1298,7 @@ static int __create_synth_event(const char *name, const char *raw_fields) > } > ret = register_synth_event(event); > if (!ret) > - dyn_event_add(&event->devent); > + dyn_event_add(&event->devent, &event->call); > else > free_synth_event(event); > out: > diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c > index ea6178cb5e33..bfef43bfce37 100644 > --- a/kernel/trace/trace_kprobe.c > +++ b/kernel/trace/trace_kprobe.c > @@ -618,7 +618,7 @@ static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to) > if (ret) > trace_probe_unlink(&tk->tp); > else > - dyn_event_add(&tk->devent); > + dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp)); > > return ret; > } > @@ -661,7 +661,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) > if (ret < 0) > unregister_kprobe_event(tk); > else > - dyn_event_add(&tk->devent); > + dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp)); > > end: > mutex_unlock(&event_mutex); > diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c > index 9b50869a5ddb..50eca53b8d22 100644 > --- a/kernel/trace/trace_uprobe.c > +++ b/kernel/trace/trace_uprobe.c > @@ -455,7 +455,7 @@ static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to) > /* Append to existing event */ > ret = trace_probe_append(&tu->tp, &to->tp); > if (!ret) > - dyn_event_add(&tu->devent); > + dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp)); > > return ret; > } > @@ -518,7 +518,7 @@ static int register_trace_uprobe(struct trace_uprobe *tu) > goto end; > } > > - dyn_event_add(&tu->devent); > + dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp)); > > end: > mutex_unlock(&event_mutex); > -- > 2.30.2
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h index ad413b382a3c..53c9dffd87fd 100644 --- a/include/linux/trace_events.h +++ b/include/linux/trace_events.h @@ -310,6 +310,7 @@ enum { TRACE_EVENT_FL_NO_SET_FILTER_BIT, TRACE_EVENT_FL_IGNORE_ENABLE_BIT, TRACE_EVENT_FL_TRACEPOINT_BIT, + TRACE_EVENT_FL_DYNAMIC_BIT, TRACE_EVENT_FL_KPROBE_BIT, TRACE_EVENT_FL_UPROBE_BIT, }; @@ -321,6 +322,7 @@ enum { * NO_SET_FILTER - Set when filter has error and is to be ignored * IGNORE_ENABLE - For trace internal events, do not enable with debugfs file * TRACEPOINT - Event is a tracepoint + * DYNAMIC - Event is a dynamic event (created at run time) * KPROBE - Event is a kprobe * UPROBE - Event is a uprobe */ @@ -330,6 +332,7 @@ enum { TRACE_EVENT_FL_NO_SET_FILTER = (1 << TRACE_EVENT_FL_NO_SET_FILTER_BIT), TRACE_EVENT_FL_IGNORE_ENABLE = (1 << TRACE_EVENT_FL_IGNORE_ENABLE_BIT), TRACE_EVENT_FL_TRACEPOINT = (1 << TRACE_EVENT_FL_TRACEPOINT_BIT), + TRACE_EVENT_FL_DYNAMIC = (1 << TRACE_EVENT_FL_DYNAMIC_BIT), TRACE_EVENT_FL_KPROBE = (1 << TRACE_EVENT_FL_KPROBE_BIT), TRACE_EVENT_FL_UPROBE = (1 << TRACE_EVENT_FL_UPROBE_BIT), }; diff --git a/kernel/trace/trace_dynevent.h b/kernel/trace/trace_dynevent.h index 7754936b57ee..936477a111d3 100644 --- a/kernel/trace/trace_dynevent.h +++ b/kernel/trace/trace_dynevent.h @@ -76,13 +76,15 @@ int dyn_event_init(struct dyn_event *ev, struct dyn_event_operations *ops) return 0; } -static inline int dyn_event_add(struct dyn_event *ev) +static inline int dyn_event_add(struct dyn_event *ev, + struct trace_event_call *call) { lockdep_assert_held(&event_mutex); if (!ev || !ev->ops) return -EINVAL; + call->flags |= TRACE_EVENT_FL_DYNAMIC; list_add_tail(&ev->list, &dyn_event_list); return 0; } diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 9315fc03e303..f4f5489e1e28 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -1298,7 +1298,7 @@ static int __create_synth_event(const char *name, const char *raw_fields) } ret = register_synth_event(event); if (!ret) - dyn_event_add(&event->devent); + dyn_event_add(&event->devent, &event->call); else free_synth_event(event); out: diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index ea6178cb5e33..bfef43bfce37 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -618,7 +618,7 @@ static int append_trace_kprobe(struct trace_kprobe *tk, struct trace_kprobe *to) if (ret) trace_probe_unlink(&tk->tp); else - dyn_event_add(&tk->devent); + dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp)); return ret; } @@ -661,7 +661,7 @@ static int register_trace_kprobe(struct trace_kprobe *tk) if (ret < 0) unregister_kprobe_event(tk); else - dyn_event_add(&tk->devent); + dyn_event_add(&tk->devent, trace_probe_event_call(&tk->tp)); end: mutex_unlock(&event_mutex); diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c index 9b50869a5ddb..50eca53b8d22 100644 --- a/kernel/trace/trace_uprobe.c +++ b/kernel/trace/trace_uprobe.c @@ -455,7 +455,7 @@ static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to) /* Append to existing event */ ret = trace_probe_append(&tu->tp, &to->tp); if (!ret) - dyn_event_add(&tu->devent); + dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp)); return ret; } @@ -518,7 +518,7 @@ static int register_trace_uprobe(struct trace_uprobe *tu) goto end; } - dyn_event_add(&tu->devent); + dyn_event_add(&tu->devent, trace_probe_event_call(&tu->tp)); end: mutex_unlock(&event_mutex);