Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220614143353.1559597-1-irogers@google.com> <20220614143353.1559597-5-irogers@google.com>
 <YwjDLl8QXQzaCYaS@tuxmaker.boeblingen.de.ibm.com>
In-Reply-To: <YwjDLl8QXQzaCYaS@tuxmaker.boeblingen.de.ibm.com>
From:   Ian Rogers <irogers@google.com>
Date:   Fri, 26 Aug 2022 09:20:20 -0700
Message-ID: <CAP-5=fWTP+_6oLhTYowvpvGrn05784rHkzJgBZcoqZobE1M_Tg@mail.gmail.com>
Subject: Re: [PATCH v2 4/6] perf cpumap: Fix alignment for masks in event encoding
To:     Alexander Gordeev <agordeev@linux.ibm.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@redhat.com>,
        Arnaldo Carvalho de Melo <acme@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Jiri Olsa <jolsa@kernel.org>,
        Namhyung Kim <namhyung@kernel.org>,
        James Clark <james.clark@arm.com>,
        Kees Cook <keescook@chromium.org>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Adrian Hunter <adrian.hunter@intel.com>,
        Riccardo Mancini <rickyman7@gmail.com>,
        German Gomez <german.gomez@arm.com>,
        Colin Ian King <colin.king@intel.com>,
        Song Liu <songliubraving@fb.com>,
        Dave Marchevsky <davemarchevsky@fb.com>,
        Athira Rajeev <atrajeev@linux.vnet.ibm.com>,
        Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com>,
        Leo Yan <leo.yan@linaro.org>, linux-perf-users@vger.kernel.org,
        linux-kernel@vger.kernel.org, Stephane Eranian <eranian@google.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Fri, Aug 26, 2022 at 5:57 AM Alexander Gordeev
<agordeev@linux.ibm.com> wrote:
>
> On Tue, Jun 14, 2022 at 07:33:51AM -0700, Ian Rogers wrote:
>
> Hi Ian,
>
> Although it is committed, still have a question.
>
> > index e7758707cadd..d2d32589758a 100644
> > --- a/tools/lib/perf/include/perf/event.h
> > +++ b/tools/lib/perf/include/perf/event.h
> > @@ -6,6 +6,7 @@
> >  #include <linux/types.h>
> >  #include <linux/limits.h>
> >  #include <linux/bpf.h>
> > +#include <linux/compiler.h>
>
> Is it correct approach to include it into user-exposed headers?
> AFAICT headers_install.sh strips #include <linux/compiler.h> and
> compiler*.h itself do not get installed with make headers_install.
>
> [...]
>
> > +struct __packed perf_record_cpu_map_data {
>
> And it is only needed to pull __packed macro, right?
>
> Thanks!

Hi Alexander,

I can see your point about compiler.h, it is true that it is just
being used for the __packed definition. Why don't you write your
proposed change as a patch and send it to LKML? libperf is more of an
experimental library than a stable API. We don't currently have any
build tests for things outside of the kernel tree.

Thanks,
Ian