This avoids usual memory_region_transaction_commit() which rebuilds
all FVs.
On POWER8 with 255 CPUs, 255 virtio-net, 40 PCI bridges guest this brings
down the boot time from 25s to 20s and reduces the amount of temporary FVs
allocated during machine constructon (~800000 -> ~640000) and amount of
temporary dispatch trees (~370000 -> ~300000), the total memory footprint
goes down (18G -> 17G).
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
memory.c | 18 +++++++++++++++---
1 file changed, 15 insertions(+), 3 deletions(-)
diff --git a/memory.c b/memory.c
index 25000d1035..d3b3581990 100644
--- a/memory.c
+++ b/memory.c
@@ -1020,6 +1020,20 @@ static void flatview_set_to_address_space(AddressSpace
*as)
}
}
+static void flatview_update_topology_single(AddressSpace *as)
+{
+ MemoryRegion *physmr = memory_region_get_flatview_root(as->root);
+ FlatView *new_view;
+
+ flatviews_init();
+ new_view = g_hash_table_lookup(flat_views, physmr);
+ if (!new_view) {
+ new_view = generate_memory_topology(physmr);
+ g_hash_table_insert(flat_views, physmr, new_view);
+ }
+ flatview_set_to_address_space(as);
+}
+
void memory_region_transaction_begin(void)
{
qemu_flush_coalesced_mmio_buffer();
@@ -2731,7 +2745,6 @@ void memory_region_invalidate_mmio_ptr(MemoryRegion *mr,
hwaddr offset,
void address_space_init(AddressSpace *as, MemoryRegion *root, const char *name)
{
memory_region_ref(root);
- memory_region_transaction_begin();
as->root = root;
as->current_map = NULL;
as->ioeventfd_nb = 0;
@@ -2739,8 +2752,7 @@ void address_space_init(AddressSpace *as, MemoryRegion
*root, const char *name)
QTAILQ_INIT(&as->listeners);
QTAILQ_INSERT_TAIL(&address_spaces, as, address_spaces_link);
as->name = g_strdup(name ? name : "anonymous");
- memory_region_update_pending |= root->enabled;
- memory_region_transaction_commit();
+ flatview_update_topology_single(as);
}
static void do_address_space_destroy(AddressSpace *as)
--
2.11.0
