Messages in this thread | | | Subject | Re: [PATCH 1/3 v2] tracepoints: Add helper to test if tracepoint is enabled in a header | From | Vlastimil Babka <> | Date | Tue, 20 Oct 2020 13:59:46 +0200 |
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On 9/25/20 11:12 PM, Steven Rostedt wrote: > From: "Steven Rostedt (VMware)" <rostedt@goodmis.org> > > As tracepoints are discouraged from being added in a header because it can > cause side effects if other tracepoints are in headers, as well as bloat the > kernel as the trace_<tracepoint>() function is not a small inline, the common > workaround is to add a function call that calls a wrapper function in a > C file that then calls the tracepoint. But as function calls add overhead, > this function should only be called when the tracepoint in question is > enabled. To get around this overhead, a static_branch can be used to only > have the tracepoint wrapper get called when the tracepoint is enabled. > > Add a tracepoint_enabled(tp) macro that gets passed the name of the > tracepoint, and this becomes a static_branch that is enabled when the > tracepoint is enabled and is a nop when the tracepoint is disabled. > > Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Nice! I'm late here, but you mentioned a v3, so FWIW:
Acked-by: Vlastimil Babka <vbabka@suse.cz>
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