From: Jiri Slaby <jsl...@suse.cz> Date: Mon, 24 Apr 2017 16:52:43 +0200
> On 04/24/2017, 04:41 PM, David Miller wrote: >>> It cannot stay as-is simply because we want to know where the functions >>> end to inject debuginfo properly. The code above does not warrant for >>> any exception. >> >> I totally and completely disagree. > > You can disagree as you wish but there is really nothing special on the > bpf code with respect to annotations. > >>> Executing a nop takes a little and having externally-callable functions >>> aligned can actually help performance (no, I haven't measured nor tested >>> the code). But sure, the tool is generic, so I can introduce a local >>> macros to avoid alignments in the functions: >> >> Not for this case, it's a bunch of entry points all packed together >> intentionally so that SKB accesses of different access sizes (which is >> almost always the case) from BPF programs use the smallest amount of >> I-cache as possible. > > And for that reason I suggested the special macros for the code (see the > macros in the e-mail you replied to again). So what problem do you > actually have with the suggested solution? If you align the entry points, then the code sequence as a whole is are no longer densely packed. Or do I misunderstand how your macros work?
