Re: [PATCH bpf-next v1] selftests/bpf: Add benchmark for tail call performance

[Alexei Starovoitov]

On Mon Jun 29, 2026 at 7:23 PM PDT, Tiezhu Yang wrote:
> --- /dev/null
> +++ b/tools/testing/selftests/bpf/benchs/run_bench_tailcall.sh
> @@ -0,0 +1,18 @@
> +#!/bin/bash
> +# SPDX-License-Identifier: GPL-2.0
> +
> +# 1. Load the official common benchmark utilities
> +source ./benchs/run_common.sh
> +
> +# 2. Strict error handling configurations
> +set -eufo pipefail
> +
> +# 3. Use default bench binary path if not exported by the framework
> +BENCH_BIN=${BENCH:-./bench}
> +
> +# 4. Run with strict core affinity and isolation for reliable profiling
> +RUN_BENCH="numactl --physcpubind=0,2 --membind=0 nice -n -20 $BENCH_BIN -w5 -d20 -a"
> +
> +# 5. Capture the output string and pass it straight into summarize_ops
> +# This satisfies the framework's internal parameter bounds without triggering set -u.

Too much LLM smell here.

In general, I don't think we need a bench for tail calls.
tail calls are more or less deprecated and often in the way of implementing
new features (like 6+ arguments). There is no need to work on
improving their performance.

pw-bot: cr