Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Fri, 22 Jul 2022 16:22:12 -0400
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Chuck Lever III <chuck.lever@oracle.com>
Cc:     Trond Myklebust <trondmy@hammerspace.com>,
        Anna Schumaker <anna.schumaker@netapp.com>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Ingo Molnar <mingo@kernel.org>, Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        linux-perf-users@vger.kernel.org
Subject: Re: [PATCH 3/4] SUNRPC: Replace dprintk() call site in
 xs_data_ready
Message-ID: <20220722162212.3d080c23@gandalf.local.home>
In-Reply-To: <9FDA46D8-4D6E-49B0-A583-D0FF739111BF@oracle.com>
References: <165851065336.361126.17865870911497306083.stgit@morisot.1015granger.net>
        <165851074247.361126.17205394769981595871.stgit@morisot.1015granger.net>
        <66371b9db4210fe853e98a8ec68b0f780ba886af.camel@hammerspace.com>
        <9FDA46D8-4D6E-49B0-A583-D0FF739111BF@oracle.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Precedence: bulk

[ Added the user space perf folks ]

On Fri, 22 Jul 2022 18:45:30 +0000
Chuck Lever III <chuck.lever@oracle.com> wrote:

> >> +TRACE_EVENT(xs_data_ready,
> >> +  TP_PROTO(
> >> +  const struct rpc_xprt *xprt
> >> +  ),
> >> +
> >> +  TP_ARGS(xprt),
> >> +
> >> +  TP_STRUCT__entry(
> >> +  __sockaddr(addr, xprt->addrlen)
> >> +  ),
> >> +
> >> +  TP_fast_assign(
> >> +  __assign_sockaddr(addr, &xprt->addr, xprt->addrlen);
> >> +  ),
> >> +
> >> +  TP_printk("peer=%pISpc", __get_sockaddr(addr))  
> > 
> > NACK. Please resolve and store the string up front instead of storing
> > the sockaddr. Most versions of perf can't resolve those kernel-specific
> > %p printks and just end up barfing on them.  
> 
> Interesting. We added get_sockaddr() to avoid this issue in
> trace-cmd. Sounds like perf needs to be fixed up too, or
> maybe this is another case of having an old libtraceevent?
> 
> Meanwhile, I can revert this back to the old way of handling
> presentation addresses.
> 

Hmm, I thought that perf now uses the external libtraceevent.

Perhaps it hasn't been updated to the latest release that has the ability
to parse this.

Maybe just install

  git://git.kernel.org/pub/scm/libs/libtrace/libtraceevent.git

?

-- Steve