adb: wait for devices to come up instead of sleeping for 3s.
Replace a hard-coded 3 second sleep with logic to wait until we've
scanned USB devices once and they've all come online.
Before:
adb shell true 0.00s user 0.00s system 0% cpu 3.047 total
After:
adb shell true 0.00s user 0.00s system 9% cpu 0.041 total
Bug: http://b/37869663
Test: `time adb shell true` after adb kill-server
Change-Id: I251d42afb885908ed9d03167287594ea16650d3f
diff --git a/adb/client/main.cpp b/adb/client/main.cpp
index 606203c..fe5099c 100644
--- a/adb/client/main.cpp
+++ b/adb/client/main.cpp
@@ -156,33 +156,38 @@
}
#endif
- // Inform our parent that we are up and running.
+ // Wait for the USB scan to complete before notifying the parent that we're up.
+ // We need to perform this in a thread, because we would otherwise block the event loop.
+ std::thread notify_thread([ack_reply_fd]() {
+ adb_wait_for_device_initialization();
- // Any error output written to stderr now goes to adb.log. We could
- // keep around a copy of the stderr fd and use that to write any errors
- // encountered by the following code, but that is probably overkill.
+ // Any error output written to stderr now goes to adb.log. We could
+ // keep around a copy of the stderr fd and use that to write any errors
+ // encountered by the following code, but that is probably overkill.
#if defined(_WIN32)
- const HANDLE ack_reply_handle = cast_int_to_handle(ack_reply_fd);
- const CHAR ack[] = "OK\n";
- const DWORD bytes_to_write = arraysize(ack) - 1;
- DWORD written = 0;
- if (!WriteFile(ack_reply_handle, ack, bytes_to_write, &written, NULL)) {
- fatal("adb: cannot write ACK to handle 0x%p: %s", ack_reply_handle,
- android::base::SystemErrorCodeToString(GetLastError()).c_str());
- }
- if (written != bytes_to_write) {
- fatal("adb: cannot write %lu bytes of ACK: only wrote %lu bytes",
- bytes_to_write, written);
- }
- CloseHandle(ack_reply_handle);
+ const HANDLE ack_reply_handle = cast_int_to_handle(ack_reply_fd);
+ const CHAR ack[] = "OK\n";
+ const DWORD bytes_to_write = arraysize(ack) - 1;
+ DWORD written = 0;
+ if (!WriteFile(ack_reply_handle, ack, bytes_to_write, &written, NULL)) {
+ fatal("adb: cannot write ACK to handle 0x%p: %s", ack_reply_handle,
+ android::base::SystemErrorCodeToString(GetLastError()).c_str());
+ }
+ if (written != bytes_to_write) {
+ fatal("adb: cannot write %lu bytes of ACK: only wrote %lu bytes", bytes_to_write,
+ written);
+ }
+ CloseHandle(ack_reply_handle);
#else
- // TODO(danalbert): Can't use SendOkay because we're sending "OK\n", not
- // "OKAY".
- if (!android::base::WriteStringToFd("OK\n", ack_reply_fd)) {
- fatal_errno("error writing ACK to fd %d", ack_reply_fd);
- }
- unix_close(ack_reply_fd);
+ // TODO(danalbert): Can't use SendOkay because we're sending "OK\n", not
+ // "OKAY".
+ if (!android::base::WriteStringToFd("OK\n", ack_reply_fd)) {
+ fatal_errno("error writing ACK to fd %d", ack_reply_fd);
+ }
+ unix_close(ack_reply_fd);
#endif
+ });
+ notify_thread.detach();
}
D("Event loop starting");