Messages in this thread | | | Date | Wed, 3 Jun 2015 15:02:57 +0200 | From | Torsten Duwe <> | Subject | [PATCH 0/4] ppc64 ftrace implementation |
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On Tue, May 19, 2015 at 11:52:47AM +0200, Jiri Kosina wrote: > On Tue, 19 May 2015, Michael Ellerman wrote: > > > > ftrace already handles recursion protection by itself (depending on the > > > per-ftrace-ops FTRACE_OPS_FL_RECURSION_SAFE flag). > > > > OK, so I wonder why that's not working for us? > > The situation when traced function recurses to itself is different from > the situation when tracing core infrastrcuture would recurse to itself > while performing tracing.
I have used this inspiration to add a catch-all parachute for ftrace_caller, see my last reply. It reappears here as patch 4/4. Expect noticable performance impact compared to the selected "notrace" attributation discussed here. This should still be done in a second step especially for the hardware assistance functions I mentioned.
Torsten
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