[Qemu-devel] [PATCH 13/22] exec: pass client mask to cpu_physical_memory_set_dirty_range

[Paolo Bonzini <pbonzini@redhat.com>]

This cuts in half the cost of bitmap operations (which will become more
expensive when made atomic) during migration on non-VRAM regions.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 exec.c                  | 23 +++++++++++++----------
 include/exec/ram_addr.h | 33 ++++++++++++++++-----------------
 memory.c                |  3 ++-
 3 files changed, 31 insertions(+), 28 deletions(-)

diff --git a/exec.c b/exec.c
index ab2468b..94b7644 100644
--- a/exec.c
+++ b/exec.c
@@ -1356,7 +1356,8 @@ int qemu_ram_resize(ram_addr_t base, ram_addr_t newsize, Error **errp)
 
     cpu_physical_memory_clear_dirty_range(block->offset, block->used_length);
     block->used_length = newsize;
-    cpu_physical_memory_set_dirty_range(block->offset, block->used_length);
+    cpu_physical_memory_set_dirty_range(block->offset, block->used_length,
+                                        DIRTY_CLIENT_ALL);
     memory_region_set_size(block->mr, newsize);
     if (block->resized) {
         block->resized(block->idstr, newsize, block->host);
@@ -1430,7 +1431,8 @@ static ram_addr_t ram_block_add(RAMBlock *new_block, Error **errp)
        }
     }
     cpu_physical_memory_set_dirty_range(new_block->offset,
-                                        new_block->used_length);
+                                        new_block->used_length,
+                                        DIRTY_CLIENT_ALL);
 
     if (new_block->host) {
         qemu_ram_setup_dump(new_block->host, new_block->max_length);
@@ -1820,7 +1822,12 @@ static void notdirty_mem_write(void *opaque, hwaddr ram_addr,
     default:
         abort();
     }
-    cpu_physical_memory_set_dirty_range_nocode(ram_addr, size);
+
+    /* Set both VGA and migration bits for simplicity and to remove
+     * the notdirty callback faster.
+     */
+    cpu_physical_memory_set_dirty_range(ram_addr, size,
+                                        DIRTY_CLIENT_NOCODE);
     tlb_set_dirty(env, current_cpu->mem_io_vaddr);
 }
 
@@ -2230,14 +2237,12 @@ static void invalidate_and_set_dirty(MemoryRegion *mr, hwaddr addr,
                                      hwaddr length)
 {
     if (cpu_physical_memory_range_includes_clean(addr, length)) {
-        dirty_log_mask = memory_region_is_logging(mr);
+        uint8_t dirty_log_mask = memory_region_is_logging(mr);
         if (dirty_log_mask & (1 << DIRTY_MEMORY_CODE)) {
             tb_invalidate_phys_range(addr, addr + length, 0);
             dirty_log_mask &= ~(1 << DIRTY_MEMORY_CODE);
         }
-        if (dirty_log_mask) {
-            cpu_physical_memory_set_dirty_range_nocode(addr, length);
-        }
+        cpu_physical_memory_set_dirty_range(addr, length, dirty_log_mask);
     } else {
         xen_modified_memory(addr, length);
     }
@@ -2865,9 +2870,7 @@ void stl_phys_notdirty(AddressSpace *as, hwaddr addr, uint32_t val)
             tb_invalidate_phys_page_range(addr1, addr1 + 4, 0);
             dirty_log_mask &= ~(1 << DIRTY_MEMORY_CODE);
         }
-        if (dirty_log_mask) {
-            cpu_physical_memory_set_dirty_range_nocode(addr1, 4);
-        }
+        cpu_physical_memory_set_dirty_range(addr1, 4, dirty_log_mask);
     }
 }
 
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 7f6e928..6c3b74e 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -41,6 +41,9 @@ void qemu_ram_free_from_ptr(ram_addr_t addr);
 
 int qemu_ram_resize(ram_addr_t base, ram_addr_t newsize, Error **errp);
 
+#define DIRTY_CLIENT_ALL	((1 << DIRTY_MEMORY_NUM) - 1)
+#define DIRTY_CLIENT_NOCODE	(DIRTY_CLIENT_ALL & ~ (1 << DIRTY_MEMORY_CODE))
+
 static inline bool cpu_physical_memory_get_dirty(ram_addr_t start,
                                                  ram_addr_t length,
                                                  unsigned client)
@@ -103,28 +106,23 @@ static inline void cpu_physical_memory_set_dirty_flag(ram_addr_t addr,
     set_bit(addr >> TARGET_PAGE_BITS, ram_list.dirty_memory[client]);
 }
 
-static inline void cpu_physical_memory_set_dirty_range_nocode(ram_addr_t start,
-                                                              ram_addr_t length)
-{
-    unsigned long end, page;
-
-    end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
-    page = start >> TARGET_PAGE_BITS;
-    bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page);
-    bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page);
-    xen_modified_memory(start, length);
-}
-
 static inline void cpu_physical_memory_set_dirty_range(ram_addr_t start,
-                                                       ram_addr_t length)
+                                                       ram_addr_t length,
+                                                       uint8_t mask)
 {
     unsigned long end, page;
 
     end = TARGET_PAGE_ALIGN(start + length) >> TARGET_PAGE_BITS;
     page = start >> TARGET_PAGE_BITS;
-    bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page);
-    bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page);
-    bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_CODE], page, end - page);
+    if (likely(mask & DIRTY_MEMORY_MIGRATION)) {
+        bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION], page, end - page);
+    }
+    if (unlikely(mask & DIRTY_MEMORY_VGA)) {
+        bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_VGA], page, end - page);
+    }
+    if (unlikely(mask & DIRTY_MEMORY_CODE)) {
+        bitmap_set(ram_list.dirty_memory[DIRTY_MEMORY_CODE], page, end - page);
+    }
     xen_modified_memory(start, length);
 }
 
@@ -172,7 +170,8 @@ static inline void cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
                     addr = page_number * TARGET_PAGE_SIZE;
                     ram_addr = start + addr;
                     cpu_physical_memory_set_dirty_range(ram_addr,
-                                       TARGET_PAGE_SIZE * hpratio);
+                                       TARGET_PAGE_SIZE * hpratio,
+                                       DIRTY_CLIENT_ALL);
                 } while (c != 0);
             }
         }
diff --git a/memory.c b/memory.c
index 76da05b..6061b27 100644
--- a/memory.c
+++ b/memory.c
@@ -1380,7 +1380,8 @@ void memory_region_set_dirty(MemoryRegion *mr, hwaddr addr,
                              hwaddr size)
 {
     assert(mr->terminates);
-    cpu_physical_memory_set_dirty_range(mr->ram_addr + addr, size);
+    cpu_physical_memory_set_dirty_range(mr->ram_addr + addr, size,
+                                        memory_region_is_logging(mr));
 }
 
 bool memory_region_test_and_clear_dirty(MemoryRegion *mr, hwaddr addr,
-- 
2.3.3