fix TestSetOOMScoreBoundaries

thaJeztah · thaJeztah · commit 3d20fa93092b · 2021-04-08T13:14:04.000+02:00
(this was introduced in 4424011) Setting the oom-score-adj to -1000 is only possible if the parent process either has no score set, or if the score is set to -1000. However, the current implementation of GetOOMScoreAdj conflates situations where either _no_ oom-score is set, _or_ oom-score is set, but set to 0. In the latter case, the test would fail: --- FAIL: TestSetOOMScoreBoundaries (0.01s) oom_linux_test.go:79: assertion failed: 0 (adjustment int) != -1000 (OOMScoreAdjMin int) FAIL To prevent failures in this situation, skip that part of the test in the above situation. Also update the description of GetOOMScoreAdj to clarify its behavior. Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
diff --git a/sys/oom_linux.go b/sys/oom_linux.go
@@ -65,7 +65,8 @@ func SetOOMScore(pid, score int) error {
 	return nil
 }
 
-// GetOOMScoreAdj gets the oom score for a process
+// GetOOMScoreAdj gets the oom score for a process. It returns 0 (zero) if either
+// no oom score is set, or a sore is set to 0.
 func GetOOMScoreAdj(pid int) (int, error) {
 	path := fmt.Sprintf("/proc/%d/oom_score_adj", pid)
 	data, err := ioutil.ReadFile(path)
diff --git a/sys/oom_linux_test.go b/sys/oom_linux_test.go
@@ -71,9 +71,11 @@ func TestSetOOMScoreBoundaries(t *testing.T) {
 
 	score, err := GetOOMScoreAdj(os.Getpid())
 	assert.NilError(t, err)
-	if score == 0 || score == OOMScoreAdjMin {
-		// we won't be able to set the score lower than the parent process,
-		// so only test if parent process does not have a oom-score-adj
+	if score == OOMScoreAdjMin {
+		// We won't be able to set the score lower than the parent process. This
+		// could also be tested if the parent process does not have a oom-score-adj
+		// set, but GetOOMScoreAdj does not distinguish between "not set" and
+		// "score is set, but zero".
 		_, adjustment, err = adjustOom(OOMScoreAdjMin)
 		assert.NilError(t, err)
 		assert.Check(t, is.Equal(adjustment, OOMScoreAdjMin))

Original file line number	Diff line number	Diff line change
`@@ -65,7 +65,8 @@ func SetOOMScore(pid, score int) error {`
`65`	`65`	`return nil`
`66`	`66`	`}`
`67`	`67`
`68`		`-// GetOOMScoreAdj gets the oom score for a process`
	`68`	`+// GetOOMScoreAdj gets the oom score for a process. It returns 0 (zero) if either`
	`69`	`+// no oom score is set, or a sore is set to 0.`
`69`	`70`	`func GetOOMScoreAdj(pid int) (int, error) {`
`70`	`71`	`path := fmt.Sprintf("/proc/%d/oom_score_adj", pid)`
`71`	`72`	`data, err := ioutil.ReadFile(path)`