File 0004-bpftool-Use-a-local-copy-of-BPF_LINK_TYPE_... of Package bpftool

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File 0004-bpftool-Use-a-local-copy-of-BPF_LINK_TYPE_PERF_EVENT.patch of Package bpftool (Revision faa1a6fb084ea3f97ec1683dfa982ade)

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From a9a8284ebebfdad29f4596c14cc9d5ae07b33430 Mon Sep 17 00:00:00 2001
From: Quentin Monnet <quentin@isovalent.com>
Date: Wed, 10 May 2023 18:22:50 +0100
Subject: [PATCH] bpftool: Use a local copy of BPF_LINK_TYPE_PERF_EVENT in
 pid_iter.bpf.c

In order to allow the BPF program in bpftool's pid_iter.bpf.c to compile
correctly on hosts where vmlinux.h does not define
BPF_LINK_TYPE_PERF_EVENT (running kernel versions lower than 5.15, for
example), define and use a local, CO-RE compatible copy of the enum
value.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
---
 tools/bpf/bpftool/skeleton/pid_iter.bpf.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/src/skeleton/pid_iter.bpf.c b/src/skeleton/pid_iter.bpf.c
index 3a4c4f7d83d8..26004f0c5a6a 100644
--- a/src/skeleton/pid_iter.bpf.c
+++ b/src/skeleton/pid_iter.bpf.c
@@ -24,6 +24,10 @@ struct perf_event___local {
 	u64 bpf_cookie;
 } __attribute__((preserve_access_index));
 
+enum bpf_link_type___local {
+	BPF_LINK_TYPE_PERF_EVENT___local = 7,
+};
+
 extern const void bpf_link_fops __ksym;
 extern const void bpf_map_fops __ksym;
 extern const void bpf_prog_fops __ksym;
@@ -93,10 +97,13 @@ int iter(struct bpf_iter__task_file *ctx)
 	e.pid = task->tgid;
 	e.id = get_obj_id(file->private_data, obj_type);
 
-	if (obj_type == BPF_OBJ_LINK) {
+	if (obj_type == BPF_OBJ_LINK &&
+	    bpf_core_enum_value_exists(enum bpf_link_type___local,
+				       BPF_LINK_TYPE_PERF_EVENT___local)) {
 		struct bpf_link *link = (struct bpf_link *) file->private_data;
 
-		if (BPF_CORE_READ(link, type) == BPF_LINK_TYPE_PERF_EVENT) {
+		if (link->type == bpf_core_enum_value(enum bpf_link_type___local,
+						      BPF_LINK_TYPE_PERF_EVENT___local)) {
 			e.has_bpf_cookie = true;
 			e.bpf_cookie = get_bpf_cookie(link);
 		}
-- 
2.40.0

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File 0004-bpftool-Use-a-local-copy-of-BPF_LINK_TYPE_PERF_EVENT.patch of Package bpftool (Revision faa1a6fb084ea3f97ec1683dfa982ade)

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