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a5da3d6568
Production BPF programs are increasing in number of instructions and states
to the point, where optimising verification process for them is necessary
to avoid running into instruction limit. Authors of those BPF programs
need to analyze verifier output, for example, collecting the most
frequent source code lines to understand which part of the program has
the biggest verification cost.
This patch introduces `--top-src-lines` flag in veristat.
`--top-src-lines=N` makes veristat output N the most popular sorce code
lines, parsed from verification log.
An example of output:
```
sudo ./veristat --top-src-lines=2 bpf_flow.bpf.o
Processing 'bpf_flow.bpf.o'...
Top source lines (_dissect):
4: (bpf_helpers.h:161) asm volatile("r1 = %[ctx]\n\t"
4: (bpf_flow.c:155) if (iph && iph->ihl == 5 &&
...
```
Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20240930231522.58650-1-mykyta.yatsenko5@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.