Re: [PATCH 1/8] perf bpf filter: Introduce basic BPF filter expression

[Adrian Hunter <adrian.hunter@intel.com>]

On 23/02/23 01:01, Namhyung Kim wrote:
> This implements a tiny parser for the filter expressions used for BPF.
> Each expression will be converted to struct perf_bpf_filter_expr and
> be passed to a BPF map.
> 
> For now, I'd like to start with the very basic comparisons like EQ or
> GT.  The LHS should be a term for sample data and the RHS is a number.
> The expressions are connected by a comma.  For example,
> 
>     period > 10000
>     ip < 0x1000000000000, cpu == 3
> 
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/Build        | 16 +++++++
>  tools/perf/util/bpf-filter.c | 37 ++++++++++++++++
>  tools/perf/util/bpf-filter.h | 36 ++++++++++++++++
>  tools/perf/util/bpf-filter.l | 82 ++++++++++++++++++++++++++++++++++++
>  tools/perf/util/bpf-filter.y | 54 ++++++++++++++++++++++++
>  5 files changed, 225 insertions(+)
>  create mode 100644 tools/perf/util/bpf-filter.c
>  create mode 100644 tools/perf/util/bpf-filter.h
>  create mode 100644 tools/perf/util/bpf-filter.l
>  create mode 100644 tools/perf/util/bpf-filter.y
> 
> diff --git a/tools/perf/util/bpf-filter.h b/tools/perf/util/bpf-filter.h
> new file mode 100644
> index 000000000000..fd5b1164a322
> --- /dev/null
> +++ b/tools/perf/util/bpf-filter.h
> @@ -0,0 +1,36 @@
> +// SPDX-License-Identifier: GPL-2.0

/* */ is preferred SPDX comment style for header files