[PATCH bpf-next 1/2] bpf: Add CGROUP to cgroup_iter order

From: Hao Luo
Date: Thu Aug 25 2022 - 17:39:29 EST


bpf_cgroup_iter_order is global visible but the entries do not have
CGROUP prefix. As requested by Andrii, put a CGROUP in the names.
This patch changes API, the following patch changes the selftest
added in a later commit that uses the API.

Fixes: d4ccaf58a847 ("bpf: Introduce cgroup iter")
Suggested-by: Andrii Nakryiko <andrii@xxxxxxxxxx>
Signed-off-by: Hao Luo <haoluo@xxxxxxxxxx>
---
include/uapi/linux/bpf.h | 10 +++---
kernel/bpf/cgroup_iter.c | 32 +++++++++----------
tools/include/uapi/linux/bpf.h | 10 +++---
.../selftests/bpf/prog_tests/btf_dump.c | 2 +-
.../selftests/bpf/prog_tests/cgroup_iter.c | 10 +++---
5 files changed, 32 insertions(+), 32 deletions(-)

diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 0f61f09f467a..bdf4bc6d8d6b 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -88,11 +88,11 @@ struct bpf_cgroup_storage_key {
};

enum bpf_cgroup_iter_order {
- BPF_ITER_ORDER_UNSPEC = 0,
- BPF_ITER_SELF_ONLY, /* process only a single object. */
- BPF_ITER_DESCENDANTS_PRE, /* walk descendants in pre-order. */
- BPF_ITER_DESCENDANTS_POST, /* walk descendants in post-order. */
- BPF_ITER_ANCESTORS_UP, /* walk ancestors upward. */
+ BPF_CGROUP_ITER_ORDER_UNSPEC = 0,
+ BPF_CGROUP_ITER_SELF_ONLY, /* process only a single object. */
+ BPF_CGROUP_ITER_DESCENDANTS_PRE, /* walk descendants in pre-order. */
+ BPF_CGROUP_ITER_DESCENDANTS_POST, /* walk descendants in post-order. */
+ BPF_CGROUP_ITER_ANCESTORS_UP, /* walk ancestors upward. */
};

union bpf_iter_link_info {
diff --git a/kernel/bpf/cgroup_iter.c b/kernel/bpf/cgroup_iter.c
index cf6d763a57d5..c69bce2f4403 100644
--- a/kernel/bpf/cgroup_iter.c
+++ b/kernel/bpf/cgroup_iter.c
@@ -74,13 +74,13 @@ static void *cgroup_iter_seq_start(struct seq_file *seq, loff_t *pos)
++*pos;
p->terminate = false;
p->visited_all = false;
- if (p->order == BPF_ITER_DESCENDANTS_PRE)
+ if (p->order == BPF_CGROUP_ITER_DESCENDANTS_PRE)
return css_next_descendant_pre(NULL, p->start_css);
- else if (p->order == BPF_ITER_DESCENDANTS_POST)
+ else if (p->order == BPF_CGROUP_ITER_DESCENDANTS_POST)
return css_next_descendant_post(NULL, p->start_css);
- else if (p->order == BPF_ITER_ANCESTORS_UP)
+ else if (p->order == BPF_CGROUP_ITER_ANCESTORS_UP)
return p->start_css;
- else /* BPF_ITER_SELF_ONLY */
+ else /* BPF_CGROUP_ITER_SELF_ONLY */
return p->start_css;
}

@@ -109,13 +109,13 @@ static void *cgroup_iter_seq_next(struct seq_file *seq, void *v, loff_t *pos)
if (p->terminate)
return NULL;

- if (p->order == BPF_ITER_DESCENDANTS_PRE)
+ if (p->order == BPF_CGROUP_ITER_DESCENDANTS_PRE)
return css_next_descendant_pre(curr, p->start_css);
- else if (p->order == BPF_ITER_DESCENDANTS_POST)
+ else if (p->order == BPF_CGROUP_ITER_DESCENDANTS_POST)
return css_next_descendant_post(curr, p->start_css);
- else if (p->order == BPF_ITER_ANCESTORS_UP)
+ else if (p->order == BPF_CGROUP_ITER_ANCESTORS_UP)
return curr->parent;
- else /* BPF_ITER_SELF_ONLY */
+ else /* BPF_CGROUP_ITER_SELF_ONLY */
return NULL;
}

@@ -188,10 +188,10 @@ static int bpf_iter_attach_cgroup(struct bpf_prog *prog,
int order = linfo->cgroup.order;
struct cgroup *cgrp;

- if (order != BPF_ITER_DESCENDANTS_PRE &&
- order != BPF_ITER_DESCENDANTS_POST &&
- order != BPF_ITER_ANCESTORS_UP &&
- order != BPF_ITER_SELF_ONLY)
+ if (order != BPF_CGROUP_ITER_DESCENDANTS_PRE &&
+ order != BPF_CGROUP_ITER_DESCENDANTS_POST &&
+ order != BPF_CGROUP_ITER_ANCESTORS_UP &&
+ order != BPF_CGROUP_ITER_SELF_ONLY)
return -EINVAL;

if (fd && id)
@@ -239,13 +239,13 @@ static void bpf_iter_cgroup_show_fdinfo(const struct bpf_iter_aux_info *aux,
kfree(buf);

show_order:
- if (aux->cgroup.order == BPF_ITER_DESCENDANTS_PRE)
+ if (aux->cgroup.order == BPF_CGROUP_ITER_DESCENDANTS_PRE)
seq_puts(seq, "order: descendants_pre\n");
- else if (aux->cgroup.order == BPF_ITER_DESCENDANTS_POST)
+ else if (aux->cgroup.order == BPF_CGROUP_ITER_DESCENDANTS_POST)
seq_puts(seq, "order: descendants_post\n");
- else if (aux->cgroup.order == BPF_ITER_ANCESTORS_UP)
+ else if (aux->cgroup.order == BPF_CGROUP_ITER_ANCESTORS_UP)
seq_puts(seq, "order: ancestors_up\n");
- else /* BPF_ITER_SELF_ONLY */
+ else /* BPF_CGROUP_ITER_SELF_ONLY */
seq_puts(seq, "order: self_only\n");
}

diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 5056cef2112f..92f7387e378a 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -88,11 +88,11 @@ struct bpf_cgroup_storage_key {
};

enum bpf_cgroup_iter_order {
- BPF_ITER_ORDER_UNSPEC = 0,
- BPF_ITER_SELF_ONLY, /* process only a single object. */
- BPF_ITER_DESCENDANTS_PRE, /* walk descendants in pre-order. */
- BPF_ITER_DESCENDANTS_POST, /* walk descendants in post-order. */
- BPF_ITER_ANCESTORS_UP, /* walk ancestors upward. */
+ BPF_CGROUP_ITER_ORDER_UNSPEC = 0,
+ BPF_CGROUP_ITER_SELF_ONLY, /* process only a single object. */
+ BPF_CGROUP_ITER_DESCENDANTS_PRE, /* walk descendants in pre-order. */
+ BPF_CGROUP_ITER_DESCENDANTS_POST, /* walk descendants in post-order. */
+ BPF_CGROUP_ITER_ANCESTORS_UP, /* walk ancestors upward. */
};

union bpf_iter_link_info {
diff --git a/tools/testing/selftests/bpf/prog_tests/btf_dump.c b/tools/testing/selftests/bpf/prog_tests/btf_dump.c
index a1bae92be1fc..7b5bbe21b549 100644
--- a/tools/testing/selftests/bpf/prog_tests/btf_dump.c
+++ b/tools/testing/selftests/bpf/prog_tests/btf_dump.c
@@ -764,7 +764,7 @@ static void test_btf_dump_struct_data(struct btf *btf, struct btf_dump *d,

/* union with nested struct */
TEST_BTF_DUMP_DATA(btf, d, "union", str, union bpf_iter_link_info, BTF_F_COMPACT,
- "(union bpf_iter_link_info){.map = (struct){.map_fd = (__u32)1,},.cgroup = (struct){.order = (enum bpf_cgroup_iter_order)BPF_ITER_SELF_ONLY,.cgroup_fd = (__u32)1,},}",
+ "(union bpf_iter_link_info){.map = (struct){.map_fd = (__u32)1,},.cgroup = (struct){.order = (enum bpf_cgroup_iter_order)BPF_CGROUP_ITER_SELF_ONLY,.cgroup_fd = (__u32)1,},}",
{ .cgroup = { .order = 1, .cgroup_fd = 1, }});

/* struct skb with nested structs/unions; because type output is so
diff --git a/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c b/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c
index 38958c37b9ce..c4a2adb38da1 100644
--- a/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c
+++ b/tools/testing/selftests/bpf/prog_tests/cgroup_iter.c
@@ -134,7 +134,7 @@ static void test_walk_preorder(struct cgroup_iter *skel)
cg_id[PARENT], cg_id[CHILD1], cg_id[CHILD2]);

read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT],
- BPF_ITER_DESCENDANTS_PRE, "preorder");
+ BPF_CGROUP_ITER_DESCENDANTS_PRE, "preorder");
}

/* Postorder walk prints child and parent in order. */
@@ -145,7 +145,7 @@ static void test_walk_postorder(struct cgroup_iter *skel)
cg_id[CHILD1], cg_id[CHILD2], cg_id[PARENT]);

read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT],
- BPF_ITER_DESCENDANTS_POST, "postorder");
+ BPF_CGROUP_ITER_DESCENDANTS_POST, "postorder");
}

/* Walking parents prints parent and then root. */
@@ -159,7 +159,7 @@ static void test_walk_ancestors_up(struct cgroup_iter *skel)
cg_id[PARENT], cg_id[ROOT]);

read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT],
- BPF_ITER_ANCESTORS_UP, "ancestors_up");
+ BPF_CGROUP_ITER_ANCESTORS_UP, "ancestors_up");

skel->bss->terminal_cgroup = 0;
}
@@ -174,7 +174,7 @@ static void test_early_termination(struct cgroup_iter *skel)
PROLOGUE "%8llu\n" EPILOGUE, cg_id[PARENT]);

read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT],
- BPF_ITER_DESCENDANTS_PRE, "early_termination");
+ BPF_CGROUP_ITER_DESCENDANTS_PRE, "early_termination");

skel->bss->terminate_early = 0;
}
@@ -186,7 +186,7 @@ static void test_walk_self_only(struct cgroup_iter *skel)
PROLOGUE "%8llu\n" EPILOGUE, cg_id[PARENT]);

read_from_cgroup_iter(skel->progs.cgroup_id_printer, cg_fd[PARENT],
- BPF_ITER_SELF_ONLY, "self_only");
+ BPF_CGROUP_ITER_SELF_ONLY, "self_only");
}

void test_cgroup_iter(void)
--
2.37.2.672.g94769d06f0-goog