Date:   Mon, 29 Nov 2021 11:07:55 -0500
From:   Steven Rostedt <rostedt@goodmis.org>
To:     Yafang Shao <laoar.shao@gmail.com>
Cc:     Sven Schnelle <svens@linux.ibm.com>,
        David Hildenbrand <david@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        netdev <netdev@vger.kernel.org>, bpf <bpf@vger.kernel.org>,
        "linux-perf-use." <linux-perf-users@vger.kernel.org>,
        linux-fsdevel@vger.kernel.org, Linux MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        kernel test robot <oliver.sang@intel.com>,
        kbuild test robot <lkp@intel.com>,
        Andrii Nakryiko <andrii@kernel.org>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
        Arnaldo Carvalho de Melo <arnaldo.melo@gmail.com>,
        Andrii Nakryiko <andrii.nakryiko@gmail.com>,
        Michal Miroslaw <mirq-linux@rere.qmqm.pl>,
        Peter Zijlstra <peterz@infradead.org>,
        Matthew Wilcox <willy@infradead.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Kees Cook <keescook@chromium.org>,
        Petr Mladek <pmladek@suse.com>
Subject: Re: [PATCH v2 7/7] tools/testing/selftests/bpf: replace open-coded
 16 with TASK_COMM_LEN
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On Mon, 29 Nov 2021 23:33:33 +0800
Yafang Shao <laoar.shao@gmail.com> wrote:

> > TBH, i would vote for reverting the change. defining an array size as
> > enum feels really odd.
> >  
> 
> We changed it to enum because the BTF can't parse macro while it can
> parse the enum type.

I wonder if BTF could take advantage of the tracing:

TRACE_DEFINE_ENUM() macros?

This is how they are converted for user space tooling.

Anyway, I'd have to go and look at why that trigger test failed. I don't
see how the size of the array caused it to change the signage of value.

-- Steve


> Anyway I don't insist on keeping this change if you think reverting it
> is better.