linux-stable.git/Documentation/bpf, branch v4.18

bpf, doc: howto use/run the BPF selftests

2018-05-15T06:02:58+00:00

I always forget howto run the BPF selftests. Thus, lets add that info
to the QA document.

Documentation was based on Cilium's documentation:
 http://cilium.readthedocs.io/en/latest/bpf/#verifying-the-setup

Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov

bpf, doc: convert bpf_devel_QA.rst to use RST formatting

2018-05-15T06:02:58+00:00

Same story as bpf_design_QA.rst RST format conversion.

Again thanks to Quentin Monnet  for
fixes and patches that have been squashed.

Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov

bpf, doc: convert bpf_design_QA.rst to use RST formatting

2018-05-15T06:02:58+00:00

The RST formatting is done such that that when rendered or converted
to different formats, an automatic index with links are created to the
subsections.

Thus, the questions are created as sections (or subsections), in-order
to get the wanted auto-generated FAQ/QA index.

Special thanks to Quentin Monnet  who
have reviewed and corrected both RST formatting and GitHub rendering
issues in this file.  Those commits have been squashed.

I've manually tested that this also renders nicely if included as part
of the kernel 'make htmldocs'.  As the end-goal is for this to become
more integrated with kernel-doc project/movement.

Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov

bpf, doc: rename txt files to rst files

2018-05-15T06:02:58+00:00

This will cause them to get auto rendered, e.g. when viewing them on GitHub.
Followup patches will correct the content to be RST compliant.

Also adjust README.rst to point to the renamed files.

Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov

bpf, doc: add basic README.rst file

2018-05-15T06:02:58+00:00

A README.rst file in a directory have special meaning for sites like
github, which auto renders the contents.  Plus search engines like
Google also index these README.rst files.

Auto rendering allow us to use links, for (re)directing eBPF users to
other places where docs live.  The end-goal would be to direct users
towards https://www.kernel.org/doc/html/latest but we haven't written
the full docs yet, so we start out small and take this incrementally.

This directory itself contains some useful docs, which can be linked
to from the README.rst file (verified this works for github).

Signed-off-by: Jesper Dangaard Brouer 
Signed-off-by: Alexei Starovoitov

bpf: Document sockmap '-target bpf' requirement for PROG_TYPE_SK_MSG

2018-04-23T21:42:21+00:00

BPF_PROG_TYPE_SK_MSG programs use a 'void *' for both data and the
data_end pointers. Additionally, the verifier ensures that every
accesses into the values is a __u64 read. This correctly maps on
to the BPF 64-bit architecture.

However, to ensure that when building on 32bit architectures that
clang uses correct types the '-target bpf' option _must_ be
specified. To make this clear add a note to the Documentation.

Signed-off-by: John Fastabend 
Acked-by: Alexei Starovoitov 
Signed-off-by: Daniel Borkmann

bpf, doc: add description wrt native/bpf clang target and pointer size

2018-03-20T22:47:45+00:00

As this recently came up on netdev [0], lets add it to the BPF devel doc.

  [0] https://www.spinics.net/lists/netdev/msg489612.html

Signed-off-by: Daniel Borkmann 
Signed-off-by: Alexei Starovoitov

bpf: add documentation to compare clang "-target bpf" and default target

2018-02-02T10:14:19+00:00

The added documentation explains how generated codes may differ
between clang bpf target and default target, and when to use
each target.

Signed-off-by: Yonghong Song 
Signed-off-by: Daniel Borkmann

bpf, doc: add faq about bpf development process

2017-12-06T22:32:42+00:00

In the same spirit of netdev FAQ, start a BPF FAQ as a collection
of expectations and/or workflow details in the context of BPF patch
processing.

Signed-off-by: Daniel Borkmann 
Acked-by: Alexei Starovoitov 
Signed-off-by: Alexei Starovoitov

bpf: document answers to common questions about BPF

2017-11-01T12:01:47+00:00

to address common misconceptions about what BPF is and what it's not
add short BPF Q&A that clarifies core BPF design principles and
answers some common questions.

Signed-off-by: Alexei Starovoitov 
Acked-by: Daniel Borkmann 
Acked-by: John Fastabend 
Acked-by: Jakub Kicinski 
Signed-off-by: David S. Miller