perf profiling: Adjust the calculation of execution time (#3089)

Author: lum1n0us

core/iwasm/aot/aot_runtime.c

@@ -2845,14 +2845,13 @@ aot_free_frame(WASMExecEnv *exec_env)
     AOTFrame *prev_frame = cur_frame->prev_frame;
 
 #if WASM_ENABLE_PERF_PROFILING != 0
-    cur_frame->func_perf_prof_info->total_exec_time +=
-        os_time_thread_cputime_us() - cur_frame->time_started;
+    uint64 elapsed = os_time_thread_cputime_us() - cur_frame->time_started;
+    cur_frame->func_perf_prof_info->total_exec_time += elapsed;
     cur_frame->func_perf_prof_info->total_exec_cnt++;
 
     /* parent function */
     if (prev_frame)
-        prev_frame->func_perf_prof_info->children_exec_time =
-            cur_frame->func_perf_prof_info->total_exec_time;
+        prev_frame->func_perf_prof_info->children_exec_time += elapsed;
 #endif
 
     wasm_exec_env_free_wasm_frame(exec_env, cur_frame);

core/iwasm/interpreter/wasm_interp_classic.c

@@ -867,13 +867,12 @@ FREE_FRAME(WASMExecEnv *exec_env, WASMInterpFrame *frame)
 #if WASM_ENABLE_PERF_PROFILING != 0
     if (frame->function) {
         WASMInterpFrame *prev_frame = frame->prev_frame;
-        frame->function->total_exec_time +=
-            os_time_thread_cputime_us() - frame->time_started;
+        uint64 elapsed = os_time_thread_cputime_us() - frame->time_started;
+        frame->function->total_exec_time += elapsed;
         frame->function->total_exec_cnt++;
 
         if (prev_frame && prev_frame->function)
-            prev_frame->function->children_exec_time +=
-                frame->function->total_exec_time;
+            prev_frame->function->children_exec_time += elapsed;
     }
 #endif
     wasm_exec_env_free_wasm_frame(exec_env, frame);

core/iwasm/interpreter/wasm_interp_fast.c

@@ -901,14 +901,12 @@ FREE_FRAME(WASMExecEnv *exec_env, WASMInterpFrame *frame)
 #if WASM_ENABLE_PERF_PROFILING != 0
     if (frame->function) {
         WASMInterpFrame *prev_frame = frame->prev_frame;
-
-        frame->function->total_exec_time +=
-            os_time_thread_cputime_us() - frame->time_started;
+        uint64 elapsed = os_time_thread_cputime_us() - frame->time_started;
+        frame->function->total_exec_time += elapsed;
         frame->function->total_exec_cnt++;
 
         if (prev_frame && prev_frame->function)
-            prev_frame->function->children_exec_time +=
-                frame->function->total_exec_time;
+            prev_frame->function->children_exec_time += elapsed;
     }
 #endif
     wasm_exec_env_free_wasm_frame(exec_env, frame);

core/iwasm/interpreter/wasm_runtime.c

@@ -3455,14 +3455,13 @@ llvm_jit_free_frame(WASMExecEnv *exec_env)
 
 #if WASM_ENABLE_PERF_PROFILING != 0
     if (frame->function) {
-        frame->function->total_exec_time +=
-            os_time_thread_cputime_us() - frame->time_started;
+        uint64 elapsed = os_time_thread_cputime_us() - frame->time_started;
+        frame->function->total_exec_time += elapsed;
         frame->function->total_exec_cnt++;
 
         /* parent function */
         if (prev_frame)
-            prev_frame->function->children_exec_time =
-                frame->function->total_exec_time;
+            prev_frame->function->children_exec_time += elapsed;
     }
 #endif
     wasm_exec_env_free_wasm_frame(exec_env, frame);