Change the method to calculate dirty-pages-rate

In function cpu_physical_memory_sync_dirty_bitmap, file
include/exec/ram_addr.h:

if (src[idx][offset]) {
    unsigned long bits = atomic_xchg(&src[idx][offset], 0);
    unsigned long new_dirty;
    new_dirty = ~dest[k];
    dest[k] |= bits;
    new_dirty &= bits;
    num_dirty += ctpopl(new_dirty);
}

After these codes executed, only the pages not dirtied in bitmap(dest),
but dirtied in dirty_memory[DIRTY_MEMORY_MIGRATION] will be calculated.
For example:
When ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION] = 0b00001111,
and atomic_rcu_read(&migration_bitmap_rcu)->bmap = 0b00000011,
the new_dirty will be 0b00001100, and this function will return 2 but not
4 which is expected.
the dirty pages in dirty_memory[DIRTY_MEMORY_MIGRATION] are all new,
so these should be calculated also.

Signed-off-by: Chao Fan <fanc.fnst@cn.fujitsu.com>
Signed-off-by: Li Zhijian <lizhijian@cn.fujitsu.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index cd432e73ae..b05dc84ab9 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -355,7 +355,8 @@ static inline void cpu_physical_memory_clear_dirty_range(ram_addr_t start,
 static inline
 uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
                                                ram_addr_t start,
-                                               ram_addr_t length)
+                                               ram_addr_t length,
+                                               int64_t *real_dirty_pages)
 {
     ram_addr_t addr;
     unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
@@ -379,6 +380,7 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
             if (src[idx][offset]) {
                 unsigned long bits = atomic_xchg(&src[idx][offset], 0);
                 unsigned long new_dirty;
+                *real_dirty_pages += ctpopl(bits);
                 new_dirty = ~dest[k];
                 dest[k] |= bits;
                 new_dirty &= bits;
@@ -398,6 +400,7 @@ uint64_t cpu_physical_memory_sync_dirty_bitmap(unsigned long *dest,
                         start + addr,
                         TARGET_PAGE_SIZE,
                         DIRTY_MEMORY_MIGRATION)) {
+                *real_dirty_pages += 1;
                 long k = (start + addr) >> TARGET_PAGE_BITS;
                 if (!test_and_set_bit(k, dest)) {
                     num_dirty++;