[Qemu-devel] [PULL 10/12] migration: Really use multiple pages at a time

[Juan Quintela]

We now send several pages at a time each time that we wakeup a thread.

Signed-off-by: Juan Quintela <quint...@redhat.com>
---
 migration/ram.c | 44 ++++++++++++++++++++++++++++++++++++++------
 1 file changed, 38 insertions(+), 6 deletions(-)

diff --git a/migration/ram.c b/migration/ram.c
index f7df6cb..8d85c49 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -391,6 +391,13 @@ void migrate_compress_threads_create(void)

 /* Multiple fd's */

+
+typedef struct {
+    int num;
+    int size;
+    uint8_t **address;
+} MultiFDPages;
+
 struct MultiFDSendParams {
     /* not changed */
     QemuThread thread;
@@ -400,7 +407,7 @@ struct MultiFDSendParams {
     QemuMutex mutex;
     /* protected by param mutex */
     bool quit;
-    uint8_t *address;
+    MultiFDPages pages;
     /* protected by multifd mutex */
     bool done;
 };
@@ -426,8 +433,8 @@ static void *multifd_send_thread(void *opaque)
             qemu_mutex_unlock(&params->mutex);
             break;
         }
-        if (params->address) {
-            params->address = 0;
+        if (params->pages.num) {
+            params->pages.num = 0;
             qemu_mutex_unlock(&params->mutex);
             qemu_mutex_lock(&multifd_send_mutex);
             params->done = true;
@@ -480,6 +487,13 @@ void migrate_multifd_send_threads_join(void)
     multifd_send = NULL;
 }

+static void multifd_init_group(MultiFDPages *pages)
+{
+    pages->num = 0;
+    pages->size = migrate_multifd_group();
+    pages->address = g_new0(uint8_t *, pages->size);
+}
+
 void migrate_multifd_send_threads_create(void)
 {
     int i, thread_count;
@@ -500,7 +514,7 @@ void migrate_multifd_send_threads_create(void)
         qemu_sem_init(&p->init, 0);
         p->quit = false;
         p->done = true;
-        p->address = 0;
+        multifd_init_group(&multifd_send[i].pages);
         p->c = socket_send_channel_create();
         if (!p->c) {
             error_report("Error creating a send channel");
@@ -515,7 +529,21 @@ void migrate_multifd_send_threads_create(void)

 static int multifd_send_page(uint8_t *address)
 {
-    int i, thread_count;
+    int i, j, thread_count;
+    static MultiFDPages pages;
+    static bool once;
+
+    if (!once) {
+        multifd_init_group(&pages);
+        once = true;
+    }
+
+    pages.address[pages.num] = address;
+    pages.num++;
+
+    if (pages.num < (pages.size - 1)) {
+        return UINT16_MAX;
+    }

     thread_count = migrate_multifd_threads();
     qemu_sem_wait(&multifd_send_sem);
@@ -528,7 +556,11 @@ static int multifd_send_page(uint8_t *address)
     }
     qemu_mutex_unlock(&multifd_send_mutex);
     qemu_mutex_lock(&multifd_send[i].mutex);
-    multifd_send[i].address = address;
+    multifd_send[i].pages.num = pages.num;
+    for (j = 0; j < pages.size; j++) {
+        multifd_send[i].pages.address[j] = pages.address[j];
+    }
+    pages.num = 0;
     qemu_mutex_unlock(&multifd_send[i].mutex);
     qemu_sem_post(&multifd_send[i].sem);

-- 
2.7.4