Re: [PATCH 06/10] Updated nfsd.proc.remove probes

[David Smith <dsmith at redhat dot com>]

On 02/25/2010 04:24 PM, Steve Dickson wrote:
> commit fcf7dae52ee72113082eb81c4b72b350b6408e00
> Author: Steve Dickson <steved@redhat.com>
> Date:   Tue Feb 23 11:50:38 2010 -0500
> 
>     Updated nfsd.proc.remove probes
>     
>     Converted the nfsd.proc.remove probes to used
>     the @cast() mechanism.
>     
>     Created the nfsd.proc4.remove probes
>     
>     Signed-off-by: Steve Dickson <steved@redhat.com>
> 
> diff --git a/tapset/nfsd.stp b/tapset/nfsd.stp
> index 41263fb..9726de0 100644
> --- a/tapset/nfsd.stp
> +++ b/tapset/nfsd.stp

> +probe nfsd.proc4.remove = kernel.function("nfsd4_remove") !,
> +                          module("nfsd").function("nfsd4_remove") ?
> +{
> +	client_ip = addr_from_rqst($rqstp)
> +	proto = $rqstp->rq_prot
> +	version = 4
> +	fh = & @cast($cstate, "nfsd4_compound_state", "kernel:nfsd")->current_fh
> +	filelen = $remove->rm_namelen
> +	filename  = kernel_string_n($remove->rm_name, filelen)
> +
> +	name = "nfsd.proc4.remove"
> +	argstr = sprintf("%s", filename);
> +
> +} 

Hmm.  I know from looking you were just following what is in
nfsd.proc3.remove, but because of the way the optimizer works, it might
be better to change this body a bit to avoid using the convenience
variables in later statements.  That way they can be optimized out easier.

Something more like this:

{
	client_ip = addr_from_rqst($rqstp)
	proto = $rqstp->rq_prot
	version = 4
	fh = & @cast($cstate, "nfsd4_compound_state", "kernel:nfsd")->current_fh
	filelen = $remove->rm_namelen
	filename  = kernel_string_n($remove->rm_name, $remove->rm_namelen)

	name = "nfsd.proc4.remove"
	argstr = sprintf("%s", kernel_string_n($remove->rm_name,
						$remove->rm_namelen));
}

I'm not sure how big of a deal this is though.

-- 
David Smith
dsmith@redhat.com
Red Hat
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