Add bpf_ktime_get_ns helper function without IR gen

Author: varun-r-mallya

examples/execve2.py

@@ -1,6 +1,6 @@
 from pythonbpf.decorators import bpf, section
 from ctypes import c_void_p, c_int64, c_int32
-
+from pythonbpf.helpers import bpf_ktime_get_ns
 
 @bpf
 @section("tracepoint/syscalls/sys_enter_execve")
@@ -11,8 +11,9 @@ def hello(ctx: c_void_p) -> c_int32:
 
 @bpf
 @section("tracepoint/syscalls/sys_exit_execve")
-def hello_again(ctx: c_void_p) -> c_int32:
+def hello_again(ctx: c_void_p) -> c_int64:
     print("exited")
-    return c_int32(0)
+    ts = bpf_ktime_get_ns()
+    return c_int64(0)
 
 LICENSE = "GPL"

pythonbpf/bpf_helper_handler.py

@@ -1,6 +1,9 @@
 import ast
 from llvmlite import ir
 
+def bpf_ktime_get_ns_emitter(call, module, builder, func):
+    pass
+
 def bpf_printk_emitter(call, module, builder, func):
     if not hasattr(func, "_fmt_counter"):
         func._fmt_counter = 0

pythonbpf/functions_pass.py

@@ -1,7 +1,7 @@
 from llvmlite import ir
 import ast
 
-from .bpf_helper_handler import bpf_printk_emitter
+from .bpf_helper_handler import bpf_printk_emitter, bpf_ktime_get_ns_emitter
 from .type_deducer import ctypes_to_ir
 
 def get_probe_string(func_node):
@@ -29,6 +29,8 @@ def process_func_body(module, builder, func_node, func, ret_type):
             call = stmt.value
             if isinstance(call.func, ast.Name) and call.func.id == "print":
                 bpf_printk_emitter(call, module, builder, func)
+            if isinstance(call.func, ast.Name) and call.func.id == "bpf_ktime_get_ns":
+                bpf_ktime_get_ns_emitter(call, module, builder, func)
         elif isinstance(stmt, ast.Return):
             if stmt.value is None:
                 builder.ret(ir.Constant(ir.IntType(32), 0))

pythonbpf/helpers.py

@@ -0,0 +1,2 @@
+def bpf_ktime_get_ns():
+    return bpf_ktime_get_ns()