Use android::base::function_ref isntead of std::function
This removes an allocation from the binder RPC calls.
Test: atest binderAllocationLimits
Bug: 230625474
Change-Id: I70ebb4e320323149c3c66809f1077cbf332c07ef
diff --git a/libs/binder/RpcState.cpp b/libs/binder/RpcState.cpp
index 4ef9cd8..c4d28c2 100644
--- a/libs/binder/RpcState.cpp
+++ b/libs/binder/RpcState.cpp
@@ -311,7 +311,7 @@
status_t RpcState::rpcSend(const sp<RpcSession::RpcConnection>& connection,
const sp<RpcSession>& session, const char* what, iovec* iovs, int niovs,
- const std::function<status_t()>& altPoll) {
+ const std::optional<android::base::function_ref<status_t()>>& altPoll) {
for (int i = 0; i < niovs; i++) {
LOG_RPC_DETAIL("Sending %s (part %d of %d) on RpcTransport %p: %s",
what, i + 1, niovs, connection->rpcTransport.get(),
@@ -335,7 +335,7 @@
const sp<RpcSession>& session, const char* what, iovec* iovs, int niovs) {
if (status_t status =
connection->rpcTransport->interruptableReadFully(session->mShutdownTrigger.get(),
- iovs, niovs, {});
+ iovs, niovs, std::nullopt);
status != OK) {
LOG_RPC_DETAIL("Failed to read %s (%d iovs) on RpcTransport %p, error: %s", what, niovs,
connection->rpcTransport.get(), statusToString(status).c_str());
@@ -369,7 +369,7 @@
.msg = RPC_CONNECTION_INIT_OKAY,
};
iovec iov{&init, sizeof(init)};
- return rpcSend(connection, session, "connection init", &iov, 1);
+ return rpcSend(connection, session, "connection init", &iov, 1, std::nullopt);
}
status_t RpcState::readConnectionInit(const sp<RpcSession::RpcConnection>& connection,
@@ -516,31 +516,32 @@
// Oneway calls have no sync point, so if many are sent before, whether this
// is a twoway or oneway transaction, they may have filled up the socket.
- // So, make sure we drain them before polling.
- std::function<status_t()> drainRefs = [&] {
- if (waitUs > kWaitLogUs) {
- ALOGE("Cannot send command, trying to process pending refcounts. Waiting %zuus. Too "
- "many oneway calls?",
- waitUs);
- }
-
- if (waitUs > 0) {
- usleep(waitUs);
- waitUs = std::min(kWaitMaxUs, waitUs * 2);
- } else {
- waitUs = 1;
- }
-
- return drainCommands(connection, session, CommandType::CONTROL_ONLY);
- };
+ // So, make sure we drain them before polling
iovec iovs[]{
{&command, sizeof(RpcWireHeader)},
{&transaction, sizeof(RpcWireTransaction)},
{const_cast<uint8_t*>(data.data()), data.dataSize()},
};
- if (status_t status =
- rpcSend(connection, session, "transaction", iovs, arraysize(iovs), drainRefs);
+ if (status_t status = rpcSend(connection, session, "transaction", iovs, arraysize(iovs),
+ [&] {
+ if (waitUs > kWaitLogUs) {
+ ALOGE("Cannot send command, trying to process pending "
+ "refcounts. Waiting %zuus. Too "
+ "many oneway calls?",
+ waitUs);
+ }
+
+ if (waitUs > 0) {
+ usleep(waitUs);
+ waitUs = std::min(kWaitMaxUs, waitUs * 2);
+ } else {
+ waitUs = 1;
+ }
+
+ return drainCommands(connection, session,
+ CommandType::CONTROL_ONLY);
+ });
status != OK) {
// TODO(b/167966510): need to undo onBinderLeaving - we know the
// refcount isn't successfully transferred.
@@ -643,7 +644,7 @@
.bodySize = sizeof(RpcDecStrong),
};
iovec iovs[]{{&cmd, sizeof(cmd)}, {&body, sizeof(body)}};
- return rpcSend(connection, session, "dec ref", iovs, arraysize(iovs));
+ return rpcSend(connection, session, "dec ref", iovs, arraysize(iovs), std::nullopt);
}
status_t RpcState::getAndExecuteCommand(const sp<RpcSession::RpcConnection>& connection,
@@ -958,7 +959,7 @@
{&rpcReply, sizeof(RpcWireReply)},
{const_cast<uint8_t*>(reply.data()), reply.dataSize()},
};
- return rpcSend(connection, session, "reply", iovs, arraysize(iovs));
+ return rpcSend(connection, session, "reply", iovs, arraysize(iovs), std::nullopt);
}
status_t RpcState::processDecStrong(const sp<RpcSession::RpcConnection>& connection,