Messages in this thread | | | Date | Thu, 27 Aug 2009 09:53:59 +0800 | From | Li Zefan <> | Subject | Re: [PATCH] tracing/profile: Fix profile_disable vs module_unload |
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> Peter is correct that he should not need to worry about modules, he > doesn't build kernels with them ;-) > > Here's another patch that moves the module ref count administration to the > trace events themselves. This should satisfy both you and Peter. >
In fact I had this patch in my mind, but I thought Peter insist on fixing it in tracepoint. So I'm fine with this. :)
> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> > > diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h > index 1b1f742..3f7c5dc 100644 > --- a/include/trace/ftrace.h > +++ b/include/trace/ftrace.h > @@ -390,6 +390,20 @@ static inline int ftrace_get_offsets_##call( \ > * > */ > > +#ifdef MODULE > +# define event_trace_up_ref() \ > + do { \ > + if (!try_module_get(THIS_MODULE)) { \ > + atomic_dec(&event_call->profile_count); \ > + return -1; \
Should return -1 or -errno like -ENOENT?
> + } \ > + } while (0) > +# define event_trace_down_ref() module_put(THIS_MODULE) > +#else > +# define event_trace_up_ref() do { } while (0) > +# define event_trace_down_ref() do { } while (0) > +#endif > + > #undef TRACE_EVENT > #define TRACE_EVENT(call, proto, args, tstruct, assign, print) \ > \ > @@ -399,16 +413,20 @@ static int ftrace_profile_enable_##call(struct ftrace_event_call *event_call) \ > { \ > int ret = 0; \ > \ > - if (!atomic_inc_return(&event_call->profile_count)) \ > + if (!atomic_inc_return(&event_call->profile_count)) { \ > + event_trace_up_ref(); \ > ret = register_trace_##call(ftrace_profile_##call); \ > + } \ > \ > return ret; \ > } \ > \ > static void ftrace_profile_disable_##call(struct ftrace_event_call *event_call)\ > { \ > - if (atomic_add_negative(-1, &event_call->profile_count)) \ > + if (atomic_add_negative(-1, &event_call->profile_count)) { \ > unregister_trace_##call(ftrace_profile_##call); \ > + event_trace_down_ref(); \ > + } \ > } > > #include TRACE_INCLUDE(TRACE_INCLUDE_FILE) > >
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