Messages in this thread | | | Subject | Re: [patch 1/2] x86_64 page fault NMI-safe | From | Peter Zijlstra <> | Date | Fri, 06 Aug 2010 11:51:40 +0200 |
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On Thu, 2010-08-05 at 21:49 -0400, Mathieu Desnoyers wrote: > * Peter Zijlstra (peterz@infradead.org) wrote: > > On Wed, 2010-08-04 at 10:45 -0400, Mathieu Desnoyers wrote: > > > > > How do you plan to read the data concurrently with the writer overwriting the > > > data while you are reading it without corruption ? > > > > I don't consider reading while writing (in overwrite mode) a valid case. > > > > If you want to use overwrite, stop the writer before reading it. > > How inconvenient. It happens that the relatively large group of users I am > working for do care for this use-case. They cannot afford to stop tracing as > soon as they hit "one bug". This "bug" could be a simple odd scenario that they > want to snapshot, but in all cases they want tracing to continue.
Snapshot is fine, just swivel the whole buffer.
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