Merge pull request #52 from pythonbpf/vmlinux-ir-gen

Dependency tree functionality to semantic analyser

Author: varun-r-mallya

pythonbpf/vmlinux_parser/class_handler.py

@@ -112,7 +112,11 @@ def process_vmlinux_post_ast(
                             type_length = elem_type._length_
 
                         if containing_type.__module__ == "vmlinux":
-                            pass
+                            new_dep_node.add_dependent(
+                                elem_type._type_.__name__
+                                if hasattr(elem_type._type_, "__name__")
+                                else str(elem_type._type_)
+                            )
                         elif containing_type.__module__ == ctypes.__name__:
                             if isinstance(elem_type, type):
                                 if issubclass(elem_type, ctypes.Array):
@@ -149,6 +153,11 @@ def process_vmlinux_post_ast(
                                 "Module not supported in recursive resolution"
                             )
                     else:
+                        new_dep_node.add_dependent(
+                            elem_type.__name__
+                            if hasattr(elem_type, "__name__")
+                            else str(elem_type)
+                        )
                         process_vmlinux_post_ast(
                             elem_type, llvm_handler, handler, processing_stack
                         )

pythonbpf/vmlinux_parser/dependency_node.py

@@ -106,6 +106,7 @@ class DependencyNode:
     """
 
     name: str
+    depends_on: Optional[list[str]] = None
     fields: Dict[str, Field] = field(default_factory=dict)
     _ready_cache: Optional[bool] = field(default=None, repr=False)
 
@@ -121,6 +122,8 @@ def add_field(
         ready: bool = False,
     ) -> None:
         """Add a field to the node with an optional initial value and readiness state."""
+        if self.depends_on is None:
+            self.depends_on = []
         self.fields[name] = Field(
             name=name,
             type=field_type,
@@ -235,3 +238,9 @@ def get_ready_fields(self) -> Dict[str, Field]:
     def get_not_ready_fields(self) -> Dict[str, Field]:
         """Get all fields that are marked as not ready."""
         return {name: elem for name, elem in self.fields.items() if not elem.ready}
+
+    def add_dependent(self, dep_type):
+        if dep_type in self.depends_on:
+            return
+        else:
+            self.depends_on.append(dep_type)

pythonbpf/vmlinux_parser/ir_generation.py

@@ -12,3 +12,6 @@ def __init__(self, module, handler: DependencyHandler):
             raise ImportError(
                 "Semantic analysis of vmlinux imports failed. Cannot generate IR"
             )
+        for struct in handler:
+            print(struct)
+            print()

tests/c-form/ex7.bpf.c

@@ -1,23 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0
 
-#include <linux/bpf.h>
+#include "vmlinux.h"
 #include <bpf/bpf_helpers.h>
 #include <bpf/bpf_tracing.h>
 
-struct trace_entry {
-  short unsigned int type;
-  unsigned char flags;
-  unsigned char preempt_count;
-  int pid;
-};
-
-struct trace_event_raw_sys_enter {
-  struct trace_entry ent;
-  long int id;
-  long unsigned int args[6];
-  char __data[0];
-};
-
 struct event {
   __u32 pid;
   __u32 uid;

tests/failing_tests/xdp_pass.py

@@ -2,7 +2,7 @@
 from pythonbpf.maps import HashMap
 from pythonbpf.helper import XDP_PASS
 from vmlinux import struct_xdp_md
-from vmlinux import struct_xdp_buff  # noqa: F401
+from vmlinux import struct_trace_event_raw_sys_enter  # noqa: F401
 from vmlinux import struct_ring_buffer_per_cpu  # noqa: F401
 
 from ctypes import c_int64