Rewrite get_sched_policy_name for safety.

This way you'll get a build time error if you make the usual mistake of
adding to the enum but not adding an entry to the array.

Also improve the unit tests, and fix get_sched_policy_name's incorrect
behavior on invalid inputs.

Bug: N/A
Test: ran tests
Change-Id: Iefcb1ec9ef66267837da7a576c8be3d0cfb16cd0
This commit is contained in:
Elliott Hughes 2018-04-25 14:52:50 -07:00
parent 419ba9e2aa
commit 9f49508f36
3 changed files with 20 additions and 18 deletions

View file

@ -164,6 +164,7 @@ cc_library {
shared_libs: ["liblog"],
header_libs: [
"libbase_headers",
"libcutils_headers",
"libutils_headers",
],

View file

@ -25,6 +25,7 @@
#include <string.h>
#include <unistd.h>
#include <android-base/macros.h>
#include <log/log.h>
/* Re-map SP_DEFAULT to the system default policy, and leave other values unchanged.
@ -460,16 +461,16 @@ int get_sched_policy(int /*tid*/, SchedPolicy* policy) {
#endif
const char *get_sched_policy_name(SchedPolicy policy)
{
const char* get_sched_policy_name(SchedPolicy policy) {
policy = _policy(policy);
static const char* const strings[SP_CNT] = {
static const char* const kSchedPolicyNames[] = {
[SP_BACKGROUND] = "bg", [SP_FOREGROUND] = "fg", [SP_SYSTEM] = " ",
[SP_AUDIO_APP] = "aa", [SP_AUDIO_SYS] = "as", [SP_TOP_APP] = "ta",
[SP_RT_APP] = "rt", [SP_RESTRICTED] = "rs",
};
if ((policy < SP_CNT) && (strings[policy] != NULL))
return strings[policy];
else
static_assert(arraysize(kSchedPolicyNames) == SP_CNT, "missing name");
if (policy < SP_BACKGROUND || policy >= SP_CNT) {
return "error";
}
return kSchedPolicyNames[policy];
}

View file

@ -60,6 +60,12 @@ long long medianSleepTime() {
return sleepTimes[median];
}
static void AssertPolicy(SchedPolicy expected_policy) {
SchedPolicy current_policy;
ASSERT_EQ(0, get_sched_policy(0, &current_policy));
EXPECT_EQ(expected_policy, current_policy);
}
TEST(SchedPolicy, set_sched_policy) {
if (!hasCapSysNice()) {
GTEST_LOG_(INFO) << "skipping test that requires CAP_SYS_NICE";
@ -76,23 +82,17 @@ TEST(SchedPolicy, set_sched_policy) {
const unsigned int BG_FG_SLACK_FACTOR = 100;
ASSERT_EQ(0, set_sched_policy(0, SP_BACKGROUND));
AssertPolicy(SP_BACKGROUND);
auto bgSleepTime = medianSleepTime();
ASSERT_EQ(0, set_sched_policy(0, SP_FOREGROUND));
AssertPolicy(SP_FOREGROUND);
auto fgSleepTime = medianSleepTime();
ASSERT_GT(bgSleepTime, fgSleepTime * BG_FG_SLACK_FACTOR);
}
TEST(SchedPolicy, get_sched_policy) {
SchedPolicy policy;
ASSERT_EQ(0, get_sched_policy(0, &policy));
const char *policyName = get_sched_policy_name(policy);
EXPECT_NE(nullptr, policyName);
EXPECT_STRNE("error", policyName);
ASSERT_EQ(0, set_sched_policy(0, SP_BACKGROUND));
SchedPolicy newPolicy;
ASSERT_EQ(0, get_sched_policy(0, &newPolicy));
EXPECT_EQ(SP_BACKGROUND, newPolicy);
TEST(SchedPolicy, get_sched_policy_name) {
EXPECT_STREQ("bg", get_sched_policy_name(SP_BACKGROUND));
EXPECT_STREQ("error", get_sched_policy_name(SchedPolicy(-2)));
EXPECT_STREQ("error", get_sched_policy_name(SP_CNT));
}