In-Reply-To: <[email protected]>
On Fri, 25 Aug 2006 14:47:04 +0100, Christoph Hellwig wrote:
> > This interface is for people writing kprobes who want to do performance
> > monitoring within their probe code. There will probably never be any
> > in-kernel users, just like there are no in-kernel users of kprobes.
>
> Wrong argument. There is a in-tree user of kprobes and I plan to submit
> a lot more.
OK. More than two years after kprobes went into the kernel, a single
in-kernel user has now appeared in 2.6.18-rc: /net/ipv4/tcp_probe.c
So by your argument kprobes should not have been merged until now.
> If people want to write kprobes for performance mintoring
> they should submit them for inclusion and we can then find a proper
> API for it - the current one is rather horrible anyway.
How so? Last time I tried it I had to manually copy parts of headers
from libpfm to get the fields but that should be easy to fix. And
some wrappers around the low-level functions might be nice but again
that's easy to add.
--
Chuck
Chuck Ebbert <[email protected]> writes:
> In-Reply-To: <[email protected]>
>
> On Fri, 25 Aug 2006 14:47:04 +0100, Christoph Hellwig wrote:
>
> > > This interface is for people writing kprobes who want to do performance
> > > monitoring within their probe code. There will probably never be any
> > > in-kernel users, just like there are no in-kernel users of kprobes.
> >
> > Wrong argument. There is a in-tree user of kprobes and I plan to submit
> > a lot more.
>
> OK. More than two years after kprobes went into the kernel, a single
> in-kernel user has now appeared in 2.6.18-rc: /net/ipv4/tcp_probe.c
No rules without exceptions. But there has to be a quite good rationale.
kprobes had one. The mythical perfmon in kernel user doesn't so far.
-Andi