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Date: Sat, 28 Mar 2015 10:21:47 -0700
From: Alexei Starovoitov <ast@plumgrid.com>
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To: He Kuang <hekuang@huawei.com>
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Subject: Re: [RFC] bpf: Suggestion on bpf syscall interface
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On 3/28/15 4:36 AM, He Kuang wrote:
> Hi, Alexei
>
> In our end-end IO module project, we use bpf maps to record
> configurations. According to current bpf syscall interface, we
> should specify map_fd to lookup/update bpf maps, so we are
> restricted to do config in the same user program.

you can pass map_fd and prog_fd from one process to another via normal
scm_rights mechanism.

> My suggestion is to export this kind of operations to sysfs, so
> we can load&attach bpf progs and config it seperately. We
> implement this feature in our demo project. What's your opinion
> on this?

Eventually we may use single sysfs file for lsmod-like listings, but I
definitely don't want to create parallel interface to maps via sysfs.
It's way too expensive and not really suitable for binary key/values.