diff mbox series

[PULL,08/25] ram/COLO: Record the dirty pages that SVM received

Message ID 20180926031650.8892-9-jasowang@redhat.com
State New
Headers show
Series [PULL,01/25] filter-rewriter: Add TCP state machine and fix memory leak in connection_track_table | expand

Commit Message

Jason Wang Sept. 26, 2018, 3:16 a.m. UTC
From: Zhang Chen <zhangckid@gmail.com>

We record the address of the dirty pages that received,
it will help flushing pages that cached into SVM.

Here, it is a trick, we record dirty pages by re-using migration
dirty bitmap. In the later patch, we will start the dirty log
for SVM, just like migration, in this way, we can record both
the dirty pages caused by PVM and SVM, we only flush those dirty
pages from RAM cache while do checkpoint.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Signed-off-by: Zhang Chen <zhangckid@gmail.com>
Signed-off-by: Zhang Chen <chen.zhang@intel.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 migration/ram.c | 43 ++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/migration/ram.c b/migration/ram.c
index 5bc8765b70..5929b61180 100644
--- a/migration/ram.c
+++ b/migration/ram.c
@@ -3409,6 +3409,15 @@  static inline void *colo_cache_from_block_offset(RAMBlock *block,
                      __func__, block->idstr);
         return NULL;
     }
+
+    /*
+    * During colo checkpoint, we need bitmap of these migrated pages.
+    * It help us to decide which pages in ram cache should be flushed
+    * into VM's RAM later.
+    */
+    if (!test_and_set_bit(offset >> TARGET_PAGE_BITS, block->bmap)) {
+        ram_state->migration_dirty_pages++;
+    }
     return block->colo_cache + offset;
 }
 
@@ -3626,7 +3635,7 @@  int colo_init_ram_cache(void)
     RAMBlock *block;
 
     rcu_read_lock();
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
         block->colo_cache = qemu_anon_ram_alloc(block->used_length,
                                                 NULL,
                                                 false);
@@ -3639,10 +3648,29 @@  int colo_init_ram_cache(void)
         memcpy(block->colo_cache, block->host, block->used_length);
     }
     rcu_read_unlock();
+    /*
+    * Record the dirty pages that sent by PVM, we use this dirty bitmap together
+    * with to decide which page in cache should be flushed into SVM's RAM. Here
+    * we use the same name 'ram_bitmap' as for migration.
+    */
+    if (ram_bytes_total()) {
+        RAMBlock *block;
+
+        RAMBLOCK_FOREACH_MIGRATABLE(block) {
+            unsigned long pages = block->max_length >> TARGET_PAGE_BITS;
+
+            block->bmap = bitmap_new(pages);
+            bitmap_set(block->bmap, 0, pages);
+        }
+    }
+    ram_state = g_new0(RAMState, 1);
+    ram_state->migration_dirty_pages = 0;
+
     return 0;
 
 out_locked:
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
         if (block->colo_cache) {
             qemu_anon_ram_free(block->colo_cache, block->used_length);
             block->colo_cache = NULL;
@@ -3658,14 +3686,23 @@  void colo_release_ram_cache(void)
 {
     RAMBlock *block;
 
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
+        g_free(block->bmap);
+        block->bmap = NULL;
+    }
+
     rcu_read_lock();
-    QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+
+    RAMBLOCK_FOREACH_MIGRATABLE(block) {
         if (block->colo_cache) {
             qemu_anon_ram_free(block->colo_cache, block->used_length);
             block->colo_cache = NULL;
         }
     }
+
     rcu_read_unlock();
+    g_free(ram_state);
+    ram_state = NULL;
 }
 
 /**