From: Kui-Feng Lee <kuifeng@fb.com>
Date: Thu, 17 Feb 2022 09:54:27 -0800
Subject: scripts/pahole-flags.sh: Parse DWARF and generate BTF with
 multithreading.
Patch-mainline: v5.18-rc1
Git-commit: b4f72786429cc57383ff41e02407726313ca178d
References: jsc#PED-1377

Pass a "-j" argument to pahole if possible to reduce the time of
generating BTF info.

Since v1.22, pahole can parse DWARF and generate BTF with
multithreading to speed up the conversion.  It will reduce the overall
build time of the kernel for seconds.

v3 fixes whitespaces and improves the commit description.
v2 checks the version of pahole to enable multithreading only if possible.

[v2] https://lore.kernel.org/bpf/20220216193431.2691015-1-kuifeng@fb.com/
[v1] https://lore.kernel.org/bpf/20220216004616.2079689-1-kuifeng@fb.com/

Signed-off-by: Kui-Feng Lee <kuifeng@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20220217175427.649713-1-kuifeng@fb.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
 scripts/pahole-flags.sh |    3 +++
 1 file changed, 3 insertions(+)

--- a/scripts/pahole-flags.sh
+++ b/scripts/pahole-flags.sh
@@ -16,5 +16,8 @@ fi
 if [ "${pahole_ver}" -ge "121" ]; then
 	extra_paholeopt="${extra_paholeopt} --btf_gen_floats"
 fi
+if [ "${pahole_ver}" -ge "122" ]; then
+	extra_paholeopt="${extra_paholeopt} -j"
+fi
 
 echo ${extra_paholeopt}