Messages in this thread | | | Date | Mon, 12 Mar 2018 23:32:34 +0100 | From | Jiri Olsa <> | Subject | Re: [PATCH 11/13] perf bpf: Add helper header files |
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On Mon, Mar 12, 2018 at 04:25:51PM -0300, Arnaldo Carvalho de Melo wrote:
SNIP
> > > > right, I kept this way, because it was already there for kernel, > > so it was fast to write ;-) > > > > but it's true we could leave it symbol based and have some sort of > > dynamic loader behaviour.. but we'd need to sort out passing the > > arguments in some generic form.. I'll check on that > > Does this answer it or am I missing something? > > Documentation/bpf/bpf_design_QA.txt > > Q: Is BPF a generic virtual machine ? > A: NO. > > BPF is generic instruction set _with_ C calling convention. > > Q: Why C calling convention was chosen? > A: Because BPF programs are designed to run in the linux kernel > which is written in C, hence BPF defines instruction set compatible > with two most used architectures x64 and arm64 (and takes into > consideration important quirks of other architectures) and > defines calling convention that is compatible with C calling > convention of the linux kernel on those architectures.
hm right, but still we interpret the calls.. so we have to call the function at the end
jirka
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