From: Song Liu <songliubraving@fb.com>
Date: Fri, 12 Nov 2021 07:02:43 -0800
Subject: bpf: Introduce btf_tracing_ids
Patch-mainline: v5.17-rc1
Git-commit: d19ddb476a539fd78ad1028ae13bb38506286931
References: jsc#PED-1377
Similar to btf_sock_ids, btf_tracing_ids provides btf ID for task_struct,
file, and vm_area_struct via easy to understand format like
btf_tracing_ids[BTF_TRACING_TYPE_[TASK|file|VMA]].
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211112150243.1270987-3-songliubraving@fb.com
Acked-by: Shung-Hsi Yu <shung-hsi.yu@suse.com>
---
include/linux/btf_ids.h | 14 +++++++++++++-
kernel/bpf/bpf_task_storage.c | 4 ++--
kernel/bpf/btf.c | 8 ++++----
kernel/bpf/stackmap.c | 2 +-
kernel/bpf/task_iter.c | 12 ++++++------
kernel/bpf/verifier.c | 2 +-
kernel/trace/bpf_trace.c | 4 ++--
7 files changed, 29 insertions(+), 17 deletions(-)
--- a/include/linux/btf_ids.h
+++ b/include/linux/btf_ids.h
@@ -189,6 +189,18 @@ MAX_BTF_SOCK_TYPE,
extern u32 btf_sock_ids[];
#endif
-extern u32 btf_task_struct_ids[];
+#define BTF_TRACING_TYPE_xxx \
+ BTF_TRACING_TYPE(BTF_TRACING_TYPE_TASK, task_struct) \
+ BTF_TRACING_TYPE(BTF_TRACING_TYPE_FILE, file) \
+ BTF_TRACING_TYPE(BTF_TRACING_TYPE_VMA, vm_area_struct)
+
+enum {
+#define BTF_TRACING_TYPE(name, type) name,
+BTF_TRACING_TYPE_xxx
+#undef BTF_TRACING_TYPE
+MAX_BTF_TRACING_TYPE,
+};
+
+extern u32 btf_tracing_ids[];
#endif
--- a/kernel/bpf/bpf_task_storage.c
+++ b/kernel/bpf/bpf_task_storage.c
@@ -323,7 +323,7 @@ const struct bpf_func_proto bpf_task_sto
.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 = &btf_task_struct_ids[0],
+ .arg2_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
.arg3_type = ARG_PTR_TO_MAP_VALUE_OR_NULL,
.arg4_type = ARG_ANYTHING,
};
@@ -334,5 +334,5 @@ const struct bpf_func_proto bpf_task_sto
.ret_type = RET_INTEGER,
.arg1_type = ARG_CONST_MAP_PTR,
.arg2_type = ARG_PTR_TO_BTF_ID,
- .arg2_btf_id = &btf_task_struct_ids[0],
+ .arg2_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
};
--- a/kernel/bpf/btf.c
+++ b/kernel/bpf/btf.c
@@ -6354,10 +6354,10 @@ const struct bpf_func_proto bpf_btf_find
.arg4_type = ARG_ANYTHING,
};
-BTF_ID_LIST_GLOBAL(btf_task_struct_ids, 3)
-BTF_ID(struct, task_struct)
-BTF_ID(struct, file)
-BTF_ID(struct, vm_area_struct)
+BTF_ID_LIST_GLOBAL(btf_tracing_ids, MAX_BTF_TRACING_TYPE)
+#define BTF_TRACING_TYPE(name, type) BTF_ID(struct, type)
+BTF_TRACING_TYPE_xxx
+#undef BTF_TRACING_TYPE
/* BTF ID set registration API for modules */
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -489,7 +489,7 @@ const struct bpf_func_proto bpf_get_task
.gpl_only = false,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_BTF_ID,
- .arg1_btf_id = &btf_task_struct_ids[0],
+ .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
.arg2_type = ARG_PTR_TO_UNINIT_MEM,
.arg3_type = ARG_CONST_SIZE_OR_ZERO,
.arg4_type = ARG_ANYTHING,
--- a/kernel/bpf/task_iter.c
+++ b/kernel/bpf/task_iter.c
@@ -622,7 +622,7 @@ const struct bpf_func_proto bpf_find_vma
.func = bpf_find_vma,
.ret_type = RET_INTEGER,
.arg1_type = ARG_PTR_TO_BTF_ID,
- .arg1_btf_id = &btf_task_struct_ids[0],
+ .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
.arg2_type = ARG_ANYTHING,
.arg3_type = ARG_PTR_TO_FUNC,
.arg4_type = ARG_PTR_TO_STACK_OR_NULL,
@@ -652,19 +652,19 @@ static int __init task_iter_init(void)
init_irq_work(&work->irq_work, do_mmap_read_unlock);
}
- task_reg_info.ctx_arg_info[0].btf_id = btf_task_struct_ids[0];
+ task_reg_info.ctx_arg_info[0].btf_id = btf_tracing_ids[BTF_TRACING_TYPE_TASK];
ret = bpf_iter_reg_target(&task_reg_info);
if (ret)
return ret;
- 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_struct_ids[1];
+ task_file_reg_info.ctx_arg_info[0].btf_id = btf_tracing_ids[BTF_TRACING_TYPE_TASK];
+ task_file_reg_info.ctx_arg_info[1].btf_id = btf_tracing_ids[BTF_TRACING_TYPE_FILE];
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_struct_ids[0];
- task_vma_reg_info.ctx_arg_info[1].btf_id = btf_task_struct_ids[2];
+ task_vma_reg_info.ctx_arg_info[0].btf_id = btf_tracing_ids[BTF_TRACING_TYPE_TASK];
+ task_vma_reg_info.ctx_arg_info[1].btf_id = btf_tracing_ids[BTF_TRACING_TYPE_VMA];
return bpf_iter_reg_target(&task_vma_reg_info);
}
late_initcall(task_iter_init);
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -6164,7 +6164,7 @@ static int set_find_vma_callback_state(s
callee->regs[BPF_REG_2].type = PTR_TO_BTF_ID;
__mark_reg_known_zero(&callee->regs[BPF_REG_2]);
callee->regs[BPF_REG_2].btf = btf_vmlinux;
- callee->regs[BPF_REG_2].btf_id = btf_task_struct_ids[2];
+ callee->regs[BPF_REG_2].btf_id = btf_tracing_ids[BTF_TRACING_TYPE_VMA],
/* pointer to stack or null */
callee->regs[BPF_REG_3] = caller->regs[BPF_REG_4];
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -764,7 +764,7 @@ const struct bpf_func_proto bpf_get_curr
.func = bpf_get_current_task_btf,
.gpl_only = true,
.ret_type = RET_PTR_TO_BTF_ID,
- .ret_btf_id = &btf_task_struct_ids[0],
+ .ret_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
};
BPF_CALL_1(bpf_task_pt_regs, struct task_struct *, task)
@@ -779,7 +779,7 @@ const struct bpf_func_proto bpf_task_pt_
.func = bpf_task_pt_regs,
.gpl_only = true,
.arg1_type = ARG_PTR_TO_BTF_ID,
- .arg1_btf_id = &btf_task_struct_ids[0],
+ .arg1_btf_id = &btf_tracing_ids[BTF_TRACING_TYPE_TASK],
.ret_type = RET_PTR_TO_BTF_ID,
.ret_btf_id = &bpf_task_pt_regs_ids[0],
};