Make required events a set

tracetools_analysis/tracetools_analysis/processor/__init__.py

@@ -138,14 +138,14 @@ class EventHandler(Dependant):
         return None
 
     @staticmethod
-    def required_events() -> List[str]:
+    def required_events() -> Set[str]:
         """
-        Get the list of events required by this EventHandler.
+        Get the set of events required by this EventHandler.
 
         Without these events, the EventHandler would be invalid/useless. Inheriting classes can
         decide not to declare that they require specific events.
         """
-        return []
+        return {}
 
     def register_processor(self, processor: 'Processor') -> None:
         """Register processor with this `EventHandler` so that it can query other handlers."""

tracetools_analysis/tracetools_analysis/processor/cpu_time.py

@@ -15,7 +15,7 @@
 """Module for CPU time events processing."""
 
 from typing import Dict
-from typing import List
+from typing import Set
 
 from tracetools_read import get_field
 
@@ -53,10 +53,10 @@ class CpuTimeHandler(EventHandler):
         self._cpu_start: Dict[int, int] = {}
 
     @staticmethod
-    def required_events() -> List[str]:
+    def required_events() -> Set[str]:
-        return [
+        return {
             'sched_switch',
-        ]
+        }
 
     @property
     def data(self) -> CpuTimeDataModel:

tracetools_analysis/tracetools_analysis/processor/memory_usage.py

@@ -15,7 +15,7 @@
 """Module for memory usage events processing."""
 
 from typing import Dict
-from typing import List
+from typing import Set
 
 from tracetools_read import get_field
 
@@ -98,11 +98,11 @@ class UserspaceMemoryUsageHandler(MemoryUsageHandler):
         self._memory: Dict[int, int] = {}
 
     @staticmethod
-    def required_events() -> List[str]:
+    def required_events() -> Set[str]:
-        return [
+        return {
             'lttng_ust_libc:malloc',
             'lttng_ust_libc:free',
-        ]
+        }
 
     def _handle_malloc(
         self, event: Dict, metadata: EventMetadata
@@ -209,11 +209,11 @@ class KernelMemoryUsageHandler(MemoryUsageHandler):
         )
 
     @staticmethod
-    def required_events() -> List[str]:
+    def required_events() -> Set[str]:
-        return [
+        return {
             'kmem_mm_page_alloc',
             'kmem_mm_page_free',
-        ]
+        }
 
     def _handle_malloc(
         self, event: Dict, metadata: EventMetadata

tracetools_analysis/tracetools_analysis/processor/profile.py

@@ -17,6 +17,7 @@
 from collections import defaultdict
 from typing import Dict
 from typing import List
+from typing import Set
 from typing import Union
 
 from tracetools_read import get_field
@@ -87,12 +88,12 @@ class ProfileHandler(EventHandler):
         self._current_funcs: Dict[int, List[List[Union[str, int]]]] = defaultdict(list)
 
     @staticmethod
-    def required_events() -> List[str]:
+    def required_events() -> Set[str]:
-        return [
+        return {
             'lttng_ust_cyg_profile_fast:func_entry',
             'lttng_ust_cyg_profile_fast:func_exit',
             'sched_switch',
-        ]
+        }
 
     @staticmethod
     def addr_to_int(addr: Union[int, str]) -> int: