debuggerd_client_test: less racy test setup
Make sure that all the threads have started up, otherwise the main part
of the test might not be testing as stressful a situation as expected.
Note that the "race" moniker is still valid because of the debuggerd
timeout.
The test is now faster (405ms) when run under good conditions.
Test: atest 'debuggerd_test:debuggerd_client#race'
Test: Ran debuggerd_client.race 1000 times on its own.
Test: Ran the whole suite of debuggerd unit tests 1000 times.
Change-Id: I487e7654a71df9f1799f09c6f385c929ddf2f234
diff --git a/debuggerd/client/debuggerd_client_test.cpp b/debuggerd/client/debuggerd_client_test.cpp
index ebb8d86..33ff05f 100644
--- a/debuggerd/client/debuggerd_client_test.cpp
+++ b/debuggerd/client/debuggerd_client_test.cpp
@@ -18,6 +18,7 @@
#include <fcntl.h>
#include <stdio.h>
+#include <sys/eventfd.h>
#include <unistd.h>
#include <chrono>
@@ -51,23 +52,35 @@
TEST(debuggerd_client, race) {
static int THREAD_COUNT = getThreadCount();
+
+ // Semaphore incremented once per thread started.
+ unique_fd barrier(eventfd(0, EFD_SEMAPHORE));
+ ASSERT_NE(-1, barrier.get());
+
pid_t forkpid = fork();
-
ASSERT_NE(-1, forkpid);
-
if (forkpid == 0) {
// Spawn a bunch of threads, to make crash_dump take longer.
std::vector<std::thread> threads;
+ threads.reserve(THREAD_COUNT);
for (int i = 0; i < THREAD_COUNT; ++i) {
- threads.emplace_back([]() {
- while (true) {
- std::this_thread::sleep_for(60s);
+ threads.emplace_back([&barrier]() {
+ uint64_t count = 1;
+ ASSERT_NE(-1, write(barrier.get(), &count, sizeof(count)));
+ for (;;) {
+ pause();
}
});
}
+ for (;;) {
+ pause();
+ }
+ }
- std::this_thread::sleep_for(60s);
- exit(0);
+ // Wait for the child to spawn all of its threads.
+ for (int i = 0; i < THREAD_COUNT; ++i) {
+ uint64_t count;
+ ASSERT_NE(-1, read(barrier.get(), &count, sizeof(count)));
}
unique_fd pipe_read, pipe_write;
@@ -77,9 +90,6 @@
constexpr int PIPE_SIZE = 16 * 1024 * 1024;
ASSERT_EQ(PIPE_SIZE, fcntl(pipe_read.get(), F_SETPIPE_SZ, PIPE_SIZE));
- // Wait for a bit to let the child spawn all of its threads.
- std::this_thread::sleep_for(1s);
-
ASSERT_TRUE(
debuggerd_trigger_dump(forkpid, kDebuggerdNativeBacktrace, 60000, std::move(pipe_write)));
// Immediately kill the forked child, to make sure that the dump didn't return early.