From 547b55d60af66397676558dfe1e652155a4c4d60 Mon Sep 17 00:00:00 2001
From: Valentin Schneider <valentin.schneider@arm.com>
Date: Mon, 8 Apr 2019 15:26:04 +0100
Subject: [PATCH 1/2] lisa/tests: RTATestBundle: Allow per-task noisiness
 threshold values

At the moment, we can completely ignore specified PIDs.

Recent test results have shown that the default 1% threshold for
`test_noisy_tasks()` is a bit too low, as certain kernel threads like
`sugov` can reach it on some of our platforms.

Modify the noisiness tweaking to allow specifying task names / regexps
for task names, and thresholds to ignore those tasks.
---
 lisa/tests/base.py | 47 +++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 42 insertions(+), 5 deletions(-)

diff --git a/lisa/tests/base.py b/lisa/tests/base.py
index 2cf1d49ea..1865e03f8 100644
--- a/lisa/tests/base.py
+++ b/lisa/tests/base.py
@@ -22,6 +22,8 @@ import os.path
 import abc
 import sys
 import textwrap
+import re
+
 from collections.abc import Mapping
 from inspect import signature, Parameter
 
@@ -379,11 +381,19 @@ class RTATestBundle(TestBundle):
     definitions.
     """
 
-    NOISE_IGNORED_PIDS = [0]
+    NOISE_ACCOUNTING_THRESHOLDS = {
+        # Idle task - ignore completely
+        0 : 100,
+        # Feeble boards like Juno/TC2 spend a while in sugov
+        r"^sugov:\d+$" : 5,
+    }
     """
-    PIDs to ignore in :meth:`test_noisy_tasks`.
+    PID/comm specific tuning for :meth:`test_noisy_tasks`
+
+    * **keys** can be PIDs, comms, or regexps for comms.
 
-    PID 0 is the idle task, don't count it as noise.
+    * **values** are noisiness thresholds (%), IOW below that runtime threshold
+      the associated task will be ignored in the noise accounting.
     """
 
     def trace_window(self, trace):
@@ -462,8 +472,35 @@ class RTATestBundle(TestBundle):
             threshold_s = min(threshold_s, noise_threshold_ms * 1e3)
 
         df = self.trace.analysis.tasks.df_tasks_runtime()
-        test_tasks = list(map(self.trace.get_task_pid, self.rtapp_profile.keys()))
-        df_noise = df[~df.index.isin(test_tasks + self.NOISE_IGNORED_PIDS)]
+
+        # We don't want to account the test tasks
+        ignored_pids = list(map(self.trace.get_task_pid, self.rtapp_profile.keys()))
+
+        def compute_duration_pct(row):
+            return row.runtime * 100 / self.trace.time_range
+
+        df["runtime_pct"] = df.apply(compute_duration_pct, axis=1)
+
+        # Figure out which PIDs to exclude from the thresholds
+        for key, threshold in self.NOISE_ACCOUNTING_THRESHOLDS.items():
+            # Find out which task(s) this threshold is about
+            if isinstance(key, int):
+                pids = [key]
+            elif isinstance(key, str):
+                comms = [comm for comm in df.comm.values if re.match(key, comm)]
+                pids = df[df.comm.isin(comms)].index.values
+            else:
+                pids = []
+
+            # For those tasks, check the threshold
+            ignored_pids += [pid for pid in pids if df.loc[pid].runtime_pct <= threshold]
+
+        log_pids = ["{} ({})".format(pid, df.loc[pid].comm) for pid in ignored_pids]
+        self.get_logger().info(
+            "Ignored PIDs for noise contribution: %s", ", ".join(log_pids))
+
+        # Filter out unwanted tasks (rt-app tasks + thresholds)
+        df_noise = df[~df.index.isin(ignored_pids)]
 
         if df_noise.empty:
             return ResultBundle.from_bool(True)
-- 
GitLab


From 15223f0a9a2411a5618e9824d3c6396fcce1629e Mon Sep 17 00:00:00 2001
From: Valentin Schneider <valentin.schneider@arm.com>
Date: Mon, 8 Apr 2019 15:41:38 +0100
Subject: [PATCH 2/2] lisa/tests/base: Remove unused imports

---
 lisa/tests/base.py | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/lisa/tests/base.py b/lisa/tests/base.py
index 1865e03f8..9f14e424a 100644
--- a/lisa/tests/base.py
+++ b/lisa/tests/base.py
@@ -25,18 +25,15 @@ import textwrap
 import re
 
 from collections.abc import Mapping
-from inspect import signature, Parameter
+from inspect import signature
 
-from devlib.target import KernelVersion
 from devlib.trace.dmesg import DmesgCollector
 
 from lisa.analysis.tasks import TasksAnalysis
-from lisa.trace import Trace, requires_events
+from lisa.trace import Trace
 from lisa.wlgen.rta import RTA
 
 from lisa.utils import Serializable, memoized, ArtifactPath
-from lisa.platforms.platinfo import PlatformInfo
-from lisa.target import Target
 from lisa.trace import FtraceCollector, FtraceConf
 
 class TestMetric:
-- 
GitLab