Commit 202fc01b authored by Alexey Kardashevskiy's avatar Alexey Kardashevskiy Committed by Paolo Bonzini
Browse files

memory: Create FlatView directly 



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: default avatarAlexey Kardashevskiy <aik@ozlabs.ru>
Message-Id: <20170921085110.25598-18-aik@ozlabs.ru>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent b516572f

memory.c

+13 −3
Original line number Diff line number Diff line
@@ -1010,6 +1010,17 @@ static void address_space_set_flatview(AddressSpace *as) 
    }

}



static void address_space_update_topology(AddressSpace *as)

{

    MemoryRegion *physmr = memory_region_get_flatview_root(as->root);



    flatviews_init();

    if (!g_hash_table_lookup(flat_views, physmr)) {

        generate_memory_topology(physmr);

    }

    address_space_set_flatview(as);

}



void memory_region_transaction_begin(void)

{

    qemu_flush_coalesced_mmio_buffer();
@@ -2721,7 +2732,6 @@ 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;
@@ -2729,8 +2739,8 @@ 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();

    address_space_update_topology(as);

    address_space_update_ioeventfds(as);

}



static void do_address_space_destroy(AddressSpace *as)