Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:6 as permitted sender) client-ip=2620:137:e000::3:6;
Sender: Ingo Molnar <mingo.kernel.org@gmail.com>
Date:   Thu, 12 Oct 2023 20:33:03 +0200
From:   Ingo Molnar <mingo@kernel.org>
To:     Namhyung Kim <namhyung@kernel.org>
Cc:     Arnaldo Carvalho de Melo <acme@kernel.org>,
        Jiri Olsa <jolsa@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Ian Rogers <irogers@google.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        LKML <linux-kernel@vger.kernel.org>,
        linux-perf-users@vger.kernel.org,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Stephane Eranian <eranian@google.com>,
        Masami Hiramatsu <mhiramat@kernel.org>,
        linux-toolchains@vger.kernel.org,
        linux-trace-devel@vger.kernel.org,
        Ben Woodard <woodard@redhat.com>,
        Joe Mario <jmario@redhat.com>,
        Kees Cook <keescook@chromium.org>,
        David Blaikie <blaikie@google.com>,
        Xu Liu <xliuprof@google.com>,
        Kan Liang <kan.liang@linux.intel.com>,
        Ravi Bangoria <ravi.bangoria@amd.com>
Subject: Re: [RFC 00/48] perf tools: Introduce data type profiling (v1)
Message-ID: <ZSg73+7Ar/U2OWMO@gmail.com>
References: <20231012035111.676789-1-namhyung@kernel.org>
 <ZSeMGPPfxkMvdaP3@gmail.com>
 <CAM9d7chzw4UeHHeXaMfPTiRdLbv7PbpK=xkgxMDojAxAc8y7Jg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAM9d7chzw4UeHHeXaMfPTiRdLbv7PbpK=xkgxMDojAxAc8y7Jg@mail.gmail.com>
Precedence: bulk


* Namhyung Kim <namhyung@kernel.org> wrote:

> > Could we perhaps add an IP filter to perf events to get this built-in?
> > Perhaps attr->exclude_user would achieve something similar?
> 
> Unfortunately IBS doesn't support privilege filters IIUC.  Maybe
> we could add a general filtering logic in the NMI handler but I'm
> afraid it can complicate the code and maybe slow it down a bit.
> Probably it's ok to have only a simple privilege filter by IP range.

It will still be so much faster than moving it through the BPF machinery, 
and bonus points if we merge this into the existing privilege-domain 
filtering ABI, so no magic 0x800000000000 constants are needed.

'Overhead' to other usecases shouldn't be much more than a single branch 
somewhere.

Thanks,

	Ingo