>From 1a33e5f2fa6de800047517a6f3251dc7191c97b5 Mon Sep 17 00:00:00 2001

From: Alon Levy <alevy@redhat.com>

Date: Wed, 16 Mar 2011 16:02:16 +0100

Subject: [PATCH 4/4] hw/qxl-render: drop cursor locks, replace with pipe

Switching locking protection of ds->cursor_set/cursor_move to moving

every call to these functions into the iothread and using the ssd->pipe

to transfer that, adding QXL_SERVER_CURSOR_SET, QXL_SERVER_CURSOR_MOVE.

This is tested with both -vnc :0 -spice and -sdl -spice.

---

 hw/qxl-render.c    |   25 +++++++++-----

 hw/qxl.c           |   90 ++++++++++++++++++++++++++++++++++++++++++++++++++++

 hw/qxl.h           |    4 ++

 ui/spice-display.h |   13 +++++++-

 4 files changed, 122 insertions(+), 10 deletions(-)

diff --git a/hw/qxl-render.c b/hw/qxl-render.c

index 58965e0..6759edb 100644

--- a/hw/qxl-render.c

+++ b/hw/qxl-render.c

@@ -178,7 +178,6 @@ fail:

     return NULL;

 }

-

 /* called from spice server thread context only */

 void qxl_render_cursor(PCIQXLDevice *qxl, QXLCommandExt *ext)

 {

@@ -209,18 +208,26 @@ void qxl_render_cursor(PCIQXLDevice *qxl, QXLCommandExt *ext)

         if (c == NULL) {

             c = cursor_builtin_left_ptr();

         }

-        qemu_mutex_lock_iothread();

-        qxl->ssd.ds->cursor_define(c);

-        qxl->ssd.ds->mouse_set(x, y, 1);

-        qemu_mutex_unlock_iothread();

-        cursor_put(c);

+        qxl_server_request_cursor_set(qxl, c, x, y);

         break;

     case QXL_CURSOR_MOVE:

         x = cmd->u.position.x;

         y = cmd->u.position.y;

-        qemu_mutex_lock_iothread();

-        qxl->ssd.ds->mouse_set(x, y, 1);

-        qemu_mutex_unlock_iothread();

+        qxl_server_request_cursor_move(qxl, x, y);

         break;

     }

 }

+

+/* called from iothread only (via qxl.c:pipe_read) */

+void qxl_render_cursor_set(SimpleSpiceDisplay *ssd, QEMUCursor *c, int x, int y)

+{

+    ssd->ds->cursor_define(c);

+    ssd->ds->mouse_set(x, y, 1);

+    cursor_put(c);

+}

+

+/* called from iothread only (via qxl.c:pipe_read) */

+void qxl_render_cursor_move(SimpleSpiceDisplay *ssd, int x, int y)

+{

+    ssd->ds->mouse_set(x, y, 1);

+}

diff --git a/hw/qxl.c b/hw/qxl.c

index cf3c938..4c27deb 100644

--- a/hw/qxl.c

+++ b/hw/qxl.c

@@ -117,6 +117,27 @@ static QXLMode qxl_modes[] = {

 #endif

 };

+typedef struct __attribute__ ((__packed__)) {

+    QEMUCursor *c;

+    int x;

+    int y;

+} QXLServerCursorSet;

+

+typedef struct __attribute__ ((__packed__)) {

+    int x;

+    int y;

+} QXLServerCursorMove;

+

+typedef struct __attribute__ ((__packed__)) {

+    unsigned char req;

+    QXLServerCursorMove data;

+} QXLServerCursorMoveRequest;

+

+typedef struct __attribute__ ((__packed__)) {

+    unsigned char req;

+    QXLServerCursorSet data;

+} QXLServerCursorSetRequest;

+

 static PCIQXLDevice *qxl0;

 static void qxl_send_events(PCIQXLDevice *d, uint32_t events);

@@ -337,6 +358,33 @@ static void interface_get_init_info(QXLInstance *sin, QXLDevInitInfo *info)

 }

 /* called from spice server thread context only */

+void qxl_server_request_cursor_set(PCIQXLDevice *qxl, QEMUCursor *c, int x, int y)

+{

+    QXLServerCursorSetRequest req;

+    int r;

+

+    req.req = QXL_SERVER_CURSOR_SET;

+    req.data.c = c;

+    req.data.x = x;

+    req.data.y = y;

+    r = write(qxl->ssd.pipe[1], &req, sizeof(req));

+    assert(r == sizeof(req));

+}

+

+/* called from spice server thread context only */

+void qxl_server_request_cursor_move(PCIQXLDevice *qxl, int x, int y)

+{

+    QXLServerCursorMoveRequest req;

+    int r;

+

+    req.req = QXL_SERVER_CURSOR_MOVE;

+    req.data.x = x;

+    req.data.y = y;

+    r = write(qxl->ssd.pipe[1], &req, sizeof(req));

+    assert(r == sizeof(req));

+}

+

+/* called from spice server thread context only */

 static int interface_get_command(QXLInstance *sin, struct QXLCommandExt *ext)

 {

     PCIQXLDevice *qxl = container_of(sin, PCIQXLDevice, ssd.qxl);

@@ -1055,12 +1103,37 @@ static void qxl_map(PCIDevice *pci, int region_num,

     }

 }

+static void read_bytes(int fd, void *buf, int len_requested)

+{

+    int len;

+    int total_len = 0;

+

+    do {

+        len = read(fd, buf, len_requested - total_len);

+        if (len < 0) {

+            if (errno == EINTR || errno == EAGAIN) {

+                continue;

+            }

+            perror("qxl: pipe_read: read failed");

+            /* will abort once it's out of the while loop */

+            break;

+        }

+        total_len += len;

+        buf = (uint8_t *)buf + len;

+    } while (total_len < len_requested);

+    assert(total_len == len_requested);

+}

+

 static void pipe_read(void *opaque)

 {

     SimpleSpiceDisplay *ssd = opaque;

     unsigned char cmd;

     int len, set_irq = 0;

     int create_update = 0;

+    int cursor_set = 0;

+    int cursor_move = 0;

+    QXLServerCursorSet cursor_set_data;

+    QXLServerCursorMove cursor_move_data;

     while (1) {

         cmd = 0;

@@ -1082,6 +1155,17 @@ static void pipe_read(void *opaque)

         case QXL_SERVER_CREATE_UPDATE:

             create_update = 1;

             break;

+        case QXL_SERVER_CURSOR_SET:

+            if (cursor_set == 1) {

+                cursor_put(cursor_set_data.c);

+            }

+            cursor_set = 1;

+            read_bytes(ssd->pipe[0], &cursor_set_data, sizeof(cursor_set_data));

+            break;

+        case QXL_SERVER_CURSOR_MOVE:

+            cursor_move = 1;

+            read_bytes(ssd->pipe[0], &cursor_move_data, sizeof(cursor_move_data));

+            break;

         default:

             fprintf(stderr, "%s: unknown cmd %u\n", __FUNCTION__, cmd);

             abort();

@@ -1099,6 +1183,12 @@ static void pipe_read(void *opaque)

     if (set_irq) {

         qxl_set_irq(container_of(ssd, PCIQXLDevice, ssd));

     }

+    if (cursor_move) {

+        qxl_render_cursor_move(ssd, cursor_move_data.x, cursor_move_data.y);

+    }

+    if (cursor_set) {

+        qxl_render_cursor_set(ssd, cursor_set_data.c, cursor_set_data.x, cursor_set_data.y);

+    }

 }

 static void qxl_send_events(PCIQXLDevice *d, uint32_t events)

diff --git a/hw/qxl.h b/hw/qxl.h

index 701245f..f4f99ec 100644

--- a/hw/qxl.h

+++ b/hw/qxl.h

@@ -93,6 +93,8 @@ typedef struct PCIQXLDevice {

 /* qxl.c */

 void *qxl_phys2virt(PCIQXLDevice *qxl, QXLPHYSICAL phys, int group_id);

+void qxl_server_request_cursor_set(PCIQXLDevice *qxl, QEMUCursor *c, int x, int y);

+void qxl_server_request_cursor_move(PCIQXLDevice *qxl, int x, int y);

 /* qxl-logger.c */

 void qxl_log_cmd_cursor(PCIQXLDevice *qxl, QXLCursorCmd *cmd, int group_id);

@@ -102,3 +104,5 @@ void qxl_log_command(PCIQXLDevice *qxl, const char *ring, QXLCommandExt *ext);

 void qxl_render_resize(PCIQXLDevice *qxl);

 void qxl_render_update(PCIQXLDevice *qxl);

 void qxl_render_cursor(PCIQXLDevice *qxl, QXLCommandExt *ext);

+void qxl_render_cursor_set(SimpleSpiceDisplay *ssd, QEMUCursor *c, int x, int y);

+void qxl_render_cursor_move(SimpleSpiceDisplay *ssd, int x, int y);

diff --git a/ui/spice-display.h b/ui/spice-display.h

index 2be6a34..bbfd689 100644

--- a/ui/spice-display.h

+++ b/ui/spice-display.h

@@ -31,11 +31,22 @@

 #define NUM_SURFACES 1024

-/* For commands/requests from server thread to iothread */

+/*

+ * Commands/requests from server thread to iothread.

+ * Note that CREATE_UPDATE is used both with qxl and without it (spice-display)

+ * the others are only used with the qxl device.

+ *

+ * SET_IRQ - just the request is sent (1 byte)

+ * CREATE_UPDATE - jus the request is sent (1 byte)

+ * CURSOR_SET - send QXLServerRequestCursorSet

+ * CURSOR_MOVE - send QXLServerRequestCursorMove

+ */

 #define QXL_EMPTY_UPDATE ((void *)-1)

 enum {

     QXL_SERVER_SET_IRQ = 1,

     QXL_SERVER_CREATE_UPDATE,

+    QXL_SERVER_CURSOR_SET,

+    QXL_SERVER_CURSOR_MOVE

 };

 struct SimpleSpiceUpdate;

-- 

1.7.3.2