Messages in this thread | | | Date | Wed, 10 Sep 2014 07:02:10 -0400 | From | Peter Hurley <> | Subject | Re: [PATCH 13/26] locking: Add non-fatal spin lock assert |
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On 09/04/2014 01:14 AM, Ingo Molnar wrote: > > * Peter Zijlstra <peterz@infradead.org> wrote: > >> On Wed, Sep 03, 2014 at 10:50:01AM -0400, Peter Hurley wrote: >>> So a lockdep-only assert is unlikely to draw attention to existing bugs, >>> especially in established drivers. >> >> By the same logic lockdep will not find locking errors in established >> drivers. > > Indeed, this patch is ill-advised in several ways: > > - it extends an API variant that we want to phase > > - emits a warning even if say lockdep has already emitted a > warning and locking state is not guaranteed to be consistent. > > - makes the kernel more expensive once fully debugged, in that > non-fatal checks are unconditional.
Ok.
One thing: I'm not seeing how lockdep_assert_held() switches off once the warning has been emitted? Is the caller expected to construct their own _ONCE tags?
Regards, Peter Hurley
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