improvement(latency_calculator): allow use it in longevity tests

defaults/test_default.yaml

@@ -268,7 +268,7 @@ zero_token_instance_type_db: 'i4i.large'
 use_zero_nodes: false
 
 latte_schema_parameters: {}
-
+workload_name: ''
 latency_decorator_error_thresholds:
   write:
     default:

sdcm/sct_config.py

@@ -1738,6 +1738,10 @@ class SCTConfiguration(dict):
              help="Error thresholds for latency decorator."
                   " Defined by dict: {<write, read, mixed>: {<default|nemesis_name>:{<metric_name>: {<rule>: <value>}}}"),
 
+        dict(name="workload_name", env="SCT_WORKLOAD_NAME", type=str,
+             help="Workload name, can be: write|read|mixed|unset."
+                  "Used for e.g. latency_calculator_decorator (use with 'use_hdr_cs_histogram' set to true)."
+                  "If unset, workload is taken from test name."),
     ]
 
     required_params = ['cluster_backend', 'test_duration', 'n_db_nodes', 'n_loaders', 'use_preinstalled_scylla',

sdcm/utils/decorators.py

@@ -162,6 +162,9 @@ def latency_calculator_decorator(original_function: Optional[Callable] = None, *
     """
     Gets the start time, end time and then calculates the latency based on function 'calculate_latency'.
 
+    For proper usage, it requires workload name (write, read, mixed) to be included in the test name
+    or setting 'workload_name' test parameter. Also requires monitoring set and 'use_hdr_cs_histogram' test parameter to be set to True.
+
     :param func: Remote method to run.
     :return: Wrapped method.
     """
@@ -212,6 +215,8 @@ def wrapped(*args, **kwargs):  # noqa: PLR0914
                 workload = 'write'
             elif 'mixed' in test_name:
                 workload = 'mixed'
+            elif tester.params.get('workload_name'):
+                workload = tester.params['workload_name']
             else:
                 return res