[PATCH bpf-next v2 2/5] bpf: Consolidate task_struct BTF_ID declarations

From: Daniel Xu
Date: Mon Aug 23 2021 - 22:44:29 EST


No need to have it defined 5 times. Once is enough.

Signed-off-by: Daniel Xu <dxu@xxxxxxxxx>
---
include/linux/btf_ids.h | 2 ++
kernel/bpf/bpf_task_storage.c | 6 ++----
kernel/bpf/stackmap.c | 4 +---
kernel/bpf/task_iter.c | 11 +++++------
kernel/trace/bpf_trace.c | 4 ++--
5 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h
index 6d1395030616..93d881ab0d48 100644
--- a/include/linux/btf_ids.h
+++ b/include/linux/btf_ids.h
@@ -188,4 +188,6 @@ MAX_BTF_SOCK_TYPE,
extern u32 btf_sock_ids[];
#endif

+extern u32 btf_task_struct_ids[];
+
#endif
diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c
index 3ce75758d394..ebfa8bc90892 100644
--- a/kernel/bpf/bpf_task_storage.c
+++ b/kernel/bpf/bpf_task_storage.c
@@ -317,15 +317,13 @@ const struct bpf_map_ops task_storage_map_ops = {
.map_owner_storage_ptr = task_storage_ptr,
};

-BTF_ID_LIST_SINGLE(bpf_task_storage_btf_ids, struct, task_struct)
-
const struct bpf_func_proto bpf_task_storage_get_proto = {
.func = bpf_task_storage_get,
.gpl_only = false,
.ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
.arg1_type = ARG_CONST_MAP_PTR,
.arg2_type = ARG_PTR_TO_BTF_ID,
- .arg2_btf_id = &bpf_task_storage_btf_ids[0],
+ .arg2_btf_id = &btf_task_struct_ids[0],
.arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL,
.arg4_type = ARG_ANYTHING,
};
@@ -336,5 +334,5 @@ const struct bpf_func_proto bpf_task_storage_delete_proto = {
.ret_type = RET_INTEGER,
.arg1_type = ARG_CONST_MAP_PTR,
.arg2_type = ARG_PTR_TO_BTF_ID,
- .arg2_btf_id = &bpf_task_storage_btf_ids[0],
+ .arg2_btf_id = &btf_task_struct_ids[0],
};
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 6fbc2abe9c91..e8eefdf8cf3e 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -530,14 +530,12 @@ BPF_CALL_4(bpf_get_task_stack, struct task_struct *, task, void *, buf,
return res;
}

-BTF_ID_LIST_SINGLE(bpf_get_task_stack_btf_ids, struct, task_struct)
-
const struct bpf_func_proto bpf_get_task_stack_proto = {
.func = bpf_get_task_stack,
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_BTF_ID,
- .arg1_btf_id = &bpf_get_task_stack_btf_ids[0],
+ .arg1_btf_id = &btf_task_struct_ids[0],
.arg2_type = ARG_PTR_TO_UNINIT_MEM,
.arg3_type = ARG_CONST_SIZE_OR_ZERO,
.arg4_type = ARG_ANYTHING,
diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c
index b68cb5d6d6eb..b48750bfba5a 100644
--- a/kernel/bpf/task_iter.c
+++ b/kernel/bpf/task_iter.c
@@ -525,7 +525,6 @@ static const struct seq_operations task_vma_seq_ops = {
};

BTF_ID_LIST(btf_task_file_ids)
-BTF_ID(struct, task_struct)
BTF_ID(struct, file)
BTF_ID(struct, vm_area_struct)

@@ -591,19 +590,19 @@ static int __init task_iter_init(void)
{
int ret;

- task_reg_info.ctx_arg_info[0].btf_id = btf_task_file_ids[0];
+ task_reg_info.ctx_arg_info[0].btf_id = btf_task_struct_ids[0];
ret = bpf_iter_reg_target(&task_reg_info);
if (ret)
return ret;

- task_file_reg_info.ctx_arg_info[0].btf_id = btf_task_file_ids[0];
- task_file_reg_info.ctx_arg_info[1].btf_id = btf_task_file_ids[1];
+ task_file_reg_info.ctx_arg_info[0].btf_id = btf_task_struct_ids[0];
+ task_file_reg_info.ctx_arg_info[1].btf_id = btf_task_file_ids[0];
ret = bpf_iter_reg_target(&task_file_reg_info);
if (ret)
return ret;

- task_vma_reg_info.ctx_arg_info[0].btf_id = btf_task_file_ids[0];
- task_vma_reg_info.ctx_arg_info[1].btf_id = btf_task_file_ids[2];
+ task_vma_reg_info.ctx_arg_info[0].btf_id = btf_task_struct_ids[0];
+ task_vma_reg_info.ctx_arg_info[1].btf_id = btf_task_file_ids[1];
return bpf_iter_reg_target(&task_vma_reg_info);
}
late_initcall(task_iter_init);
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index cbc73c08c4a4..50d055fc2327 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -714,13 +714,13 @@ BPF_CALL_0(bpf_get_current_task_btf)
return (unsigned long) current;
}

-BTF_ID_LIST_SINGLE(bpf_get_current_btf_ids, struct, task_struct)
+BTF_ID_LIST_GLOBAL_SINGLE(btf_task_struct_ids, struct, task_struct)

static const struct bpf_func_proto bpf_get_current_task_btf_proto = {
.func = bpf_get_current_task_btf,
.gpl_only = true,
.ret_type = RET_PTR_TO_BTF_ID,
- .ret_btf_id = &bpf_get_current_btf_ids[0],
+ .ret_btf_id = &btf_task_struct_ids[0],
};

BPF_CALL_2(bpf_current_task_under_cgroup, struct bpf_map *, map, u32, idx)
--
2.33.0