From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Berg <johannes@sipsolutions.net>
Subject: Re: eBPF - little-endian load instructions?
Date: Wed, 12 Apr 2017 15:02:00 +0200
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Cc: "netdev@vger.kernel.org" <netdev@vger.kernel.org>,
        Alexei Starovoitov <ast@kernel.org>
To: Daniel Borkmann <daniel@iogearbox.net>
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On Tue, 2017-04-11 at 13:06 +0200, Daniel Borkmann wrote:
> 
> There are instructions to convert endianess, see __bpf_prog_run(),
> the ALU_END_TO_BE, ALU_END_TO_LE labels for details. There's a
> BPF_ENDIAN() macro used in the test suite and other places.

Are these hooked up to llvm intrinsics or so? If not, can I do that
through some kind of inline asm statement?

In the samples, I only see people doing

#define _htonl __builtin_bswap32

but I'm not even completely convinced that's correct, since it assumes
a little-endian host?

johannes