[TAPSETS] Linux Kernel Event Trace Tool

[Mathieu Desnoyers]

* Frank Ch. Eigler (fche@redhat.com) wrote:
> 
> Mathieu Desnoyers <compudj@krystal.dyndns.org> writes:
> 
> > [...]  The cleanest way I found to log NMIs without losing event is
> > to make the logging code reentrant by itself by using atomic
> > operations.
> 
> This approach may not work so easily for systemtap, since scripts have
> a lot more local state (context) than a single tracing function call.
> Plus they sometimes hold locks, during which reentrancy is bad.
> 

I understand. My suggestion is to use a reentrant mechanism when the goal is to
log information to a buffer without preprocessing. I understand that SystemTAP
preprocessing might not be easily doable atomically.

Mathieu

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