On 12/1/23 15:46, Steven Rostedt wrote: > On Fri, 1 Dec 2023 15:17:35 +0100 > Petr Pavlu <petr.pa...@suse.com> wrote: > >> Ok, keeping the current approach, my plan for v2 is to prepare the >> following patches: >> >> [...] >> * Fix the potential race between trace_buffered_event_enable() and >> trace_event_buffer_lock_reserve() where the latter might already see >> a valid trace_buffered_event pointer but not all initialization yet. >> >> I think this might be actually best to address by using the same >> maintenance exclusion as is implemented in >> trace_buffered_event_disable(). It would make both maintenance >> operations consistent but for the cost of making the enable operation >> somewhat slower. > > I wouldn't do them the same just to make them consistent. I think the > smp_wmb() is sufficient. Don't you think?
Looking at this again, I think it is actually a non-issue. Function trace_buffered_event_enable() only writes the header part of ring_buffer_event but that is never written nor read by the actual users which obtain the buffer from trace_event_buffer_lock_reserve(). No change is then needed, it is left out in v2 of the series. -- Petr