Re: [PATCH v2 2.6.38-rc8-tip 17/20] 17: uprobes: filter chain

From: Stephen Wilson
Date: Fri Mar 18 2011 - 18:11:57 EST



On Sat, Mar 19, 2011 at 12:46:48AM +0530, Srikar Dronamraju wrote:
> > > + for (consumer = uprobe->consumers; consumer;
> > > + consumer = consumer->next) {
> > > + if (!consumer->filter || consumer->filter(consumer, t)) {
> >
> > The implementation does not seem to match the changelog description.
> > Should this not be:
> >
> > if (consumer->filter && consumer->filter(consumer, t))
> >
> > ?
>
> filter is optional; if filter is present, then it means that the
> tracer is interested in a specific set of processes that maps this
> inode. If there is no filter; it means that it is interested in all
> processes that map this filter.

Ah OK. That does make sense then. Thanks!


> filter_chain() should return true if any consumer is interested in
> tracing this task. if there is a consumer who hasnt defined a filter
> then we dont need to loop thro remaining consumers.
>
> Hence
>
> if (!consumer->filter || consumer->filter(consumer, t)) {
>
> seems better suited to me.

--
steve

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