diff --git a/src/core/lib/iomgr/tcp_windows.cc b/src/core/lib/iomgr/tcp_windows.cc
index 86ee1010cf7..aaf9fb4ea8a 100644
--- a/src/core/lib/iomgr/tcp_windows.cc
+++ b/src/core/lib/iomgr/tcp_windows.cc
@@ -113,10 +113,7 @@ typedef struct grpc_tcp {
grpc_closure* read_cb;
grpc_closure* write_cb;
-
- /* garbage after the last read */
- grpc_slice_buffer last_read_buffer;
-
+ grpc_slice read_slice;
grpc_slice_buffer* write_slices;
grpc_slice_buffer* read_slices;
@@ -135,7 +132,6 @@ static void tcp_free(grpc_tcp* tcp) {
grpc_winsocket_destroy(tcp->socket);
gpr_mu_destroy(&tcp->mu);
gpr_free(tcp->peer_string);
- grpc_slice_buffer_destroy_internal(&tcp->last_read_buffer);
grpc_resource_user_unref(tcp->resource_user);
if (tcp->shutting_down) GRPC_ERROR_UNREF(tcp->shutdown_error);
gpr_free(tcp);
@@ -184,6 +180,7 @@ static void on_read(void* tcpp, grpc_error* error) {
grpc_tcp* tcp = (grpc_tcp*)tcpp;
grpc_closure* cb = tcp->read_cb;
grpc_winsocket* socket = tcp->socket;
+ grpc_slice sub;
grpc_winsocket_callback_info* info = &socket->read_info;
if (grpc_tcp_trace.enabled()) {
@@ -197,19 +194,11 @@ static void on_read(void* tcpp, grpc_error* error) {
char* utf8_message = gpr_format_message(info->wsa_error);
error = GRPC_ERROR_CREATE_FROM_COPIED_STRING(utf8_message);
gpr_free(utf8_message);
- grpc_slice_buffer_reset_and_unref_internal(tcp->read_slices);
+ grpc_slice_unref_internal(tcp->read_slice);
} else {
if (info->bytes_transfered != 0 && !tcp->shutting_down) {
- GPR_ASSERT((size_t)info->bytes_transfered <= tcp->read_slices->length);
- if (static_cast<size_t>(info->bytes_transfered) !=
- tcp->read_slices->length) {
- grpc_slice_buffer_trim_end(
- tcp->read_slices,
- tcp->read_slices->length -
- static_cast<size_t>(info->bytes_transfered),
- &tcp->last_read_buffer);
- }
- GPR_ASSERT((size_t)info->bytes_transfered == tcp->read_slices->length);
+ sub = grpc_slice_sub_no_ref(tcp->read_slice, 0, info->bytes_transfered);
+ grpc_slice_buffer_add(tcp->read_slices, sub);
if (grpc_tcp_trace.enabled()) {
size_t i;
@@ -225,7 +214,7 @@ static void on_read(void* tcpp, grpc_error* error) {
if (grpc_tcp_trace.enabled()) {
gpr_log(GPR_INFO, "TCP:%p unref read_slice", tcp);
}
- grpc_slice_buffer_reset_and_unref_internal(tcp->read_slices);
+ grpc_slice_unref_internal(tcp->read_slice);
error = tcp->shutting_down
? GRPC_ERROR_CREATE_REFERENCING_FROM_STATIC_STRING(
"TCP stream shutting down", &tcp->shutdown_error, 1)
@@ -239,8 +228,6 @@ static void on_read(void* tcpp, grpc_error* error) {
GRPC_CLOSURE_SCHED(cb, error);
}
-#define DEFAULT_TARGET_READ_SIZE 8192
-#define MAX_WSABUF_COUNT 16
static void win_read(grpc_endpoint* ep, grpc_slice_buffer* read_slices,
grpc_closure* cb) {
grpc_tcp* tcp = (grpc_tcp*)ep;
@@ -249,8 +236,7 @@ static void win_read(grpc_endpoint* ep, grpc_slice_buffer* read_slices,
int status;
DWORD bytes_read = 0;
DWORD flags = 0;
- WSABUF buffers[MAX_WSABUF_COUNT];
- size_t i;
+ WSABUF buffer;
if (grpc_tcp_trace.enabled()) {
gpr_log(GPR_INFO, "TCP:%p win_read", tcp);
@@ -266,27 +252,18 @@ static void win_read(grpc_endpoint* ep, grpc_slice_buffer* read_slices,
tcp->read_cb = cb;
tcp->read_slices = read_slices;
grpc_slice_buffer_reset_and_unref_internal(read_slices);
- grpc_slice_buffer_swap(read_slices, &tcp->last_read_buffer);
- if (tcp->read_slices->length < DEFAULT_TARGET_READ_SIZE / 2 &&
- tcp->read_slices->count < MAX_WSABUF_COUNT) {
- // TODO(jtattermusch): slice should be allocated using resource quota
- grpc_slice_buffer_add(tcp->read_slices,
- GRPC_SLICE_MALLOC(DEFAULT_TARGET_READ_SIZE));
- }
+ tcp->read_slice = GRPC_SLICE_MALLOC(8192);
- GPR_ASSERT(tcp->read_slices->count <= MAX_WSABUF_COUNT);
- for (i = 0; i < tcp->read_slices->count; i++) {
- buffers[i].len = (ULONG)GRPC_SLICE_LENGTH(
- tcp->read_slices->slices[i]); // we know slice size fits in 32bit.
- buffers[i].buf = (char*)GRPC_SLICE_START_PTR(tcp->read_slices->slices[i]);
- }
+ buffer.len = (ULONG)GRPC_SLICE_LENGTH(
+ tcp->read_slice); // we know slice size fits in 32bit.
+ buffer.buf = (char*)GRPC_SLICE_START_PTR(tcp->read_slice);
TCP_REF(tcp, "read");
/* First let's try a synchronous, non-blocking read. */
- status = WSARecv(tcp->socket->socket, buffers, (DWORD)tcp->read_slices->count,
- &bytes_read, &flags, NULL, NULL);
+ status =
+ WSARecv(tcp->socket->socket, &buffer, 1, &bytes_read, &flags, NULL, NULL);
info->wsa_error = status == 0 ? 0 : WSAGetLastError();
/* Did we get data immediately ? Yay. */
@@ -298,8 +275,8 @@ static void win_read(grpc_endpoint* ep, grpc_slice_buffer* read_slices,
/* Otherwise, let's retry, by queuing a read. */
memset(&tcp->socket->read_info.overlapped, 0, sizeof(OVERLAPPED));
- status = WSARecv(tcp->socket->socket, buffers, (DWORD)tcp->read_slices->count,
- &bytes_read, &flags, &info->overlapped, NULL);
+ status = WSARecv(tcp->socket->socket, &buffer, 1, &bytes_read, &flags,
+ &info->overlapped, NULL);
if (status != 0) {
int wsa_error = WSAGetLastError();
@@ -353,7 +330,7 @@ static void win_write(grpc_endpoint* ep, grpc_slice_buffer* slices,
unsigned i;
DWORD bytes_sent;
int status;
- WSABUF local_buffers[MAX_WSABUF_COUNT];
+ WSABUF local_buffers[16];
WSABUF* allocated = NULL;
WSABUF* buffers = local_buffers;
size_t len;
@@ -472,7 +449,6 @@ static void win_shutdown(grpc_endpoint* ep, grpc_error* why) {
static void win_destroy(grpc_endpoint* ep) {
grpc_network_status_unregister_endpoint(ep);
grpc_tcp* tcp = (grpc_tcp*)ep;
- grpc_slice_buffer_reset_and_unref_internal(&tcp->last_read_buffer);
TCP_UNREF(tcp, "destroy");
}
@@ -524,7 +500,6 @@ grpc_endpoint* grpc_tcp_create(grpc_winsocket* socket,
GRPC_CLOSURE_INIT(&tcp->on_read, on_read, tcp, grpc_schedule_on_exec_ctx);
GRPC_CLOSURE_INIT(&tcp->on_write, on_write, tcp, grpc_schedule_on_exec_ctx);
tcp->peer_string = gpr_strdup(peer_string);
- grpc_slice_buffer_init(&tcp->last_read_buffer);
tcp->resource_user = grpc_resource_user_create(resource_quota, peer_string);
/* Tell network status tracking code about the new endpoint */
grpc_network_status_register_endpoint(&tcp->base);