exec: Change RAMBlockIterFunc definition

Currently, qemu_ram_foreach_* calls RAMBlockIterFunc with many
block-specific arguments. But often iter func needs RAMBlock*.
This refactoring is needed for fast access to RAMBlock flags from
qemu_ram_foreach_block's callback. The only way to achieve this now
is to call qemu_ram_block_from_host (which also enumerates blocks).

So, this patch reduces complexity of
qemu_ram_foreach_block() -> cb() -> qemu_ram_block_from_host()
from O(n^2) to O(n).

Fix RAMBlockIterFunc definition and add some functions to read
RAMBlock* fields witch were passed.

Signed-off-by: Yury Kotov <yury-kotov@yandex-team.ru>
Message-Id: <20190215174548.2630-2-yury-kotov@yandex-team.ru>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/migration/rdma.c b/migration/rdma.c
index d5251cd820..b0115e4de5 100644
--- a/migration/rdma.c
+++ b/migration/rdma.c
@@ -624,9 +624,12 @@ static int rdma_add_block(RDMAContext *rdma, const char *block_name,
  * in advanced before the migration starts. This tells us where the RAM blocks
  * are so that we can register them individually.
  */
-static int qemu_rdma_init_one_block(const char *block_name, void *host_addr,
-    ram_addr_t block_offset, ram_addr_t length, void *opaque)
+static int qemu_rdma_init_one_block(RAMBlock *rb, void *opaque)
 {
+    const char *block_name = qemu_ram_get_idstr(rb);
+    void *host_addr = qemu_ram_get_host_addr(rb);
+    ram_addr_t block_offset = qemu_ram_get_offset(rb);
+    ram_addr_t length = qemu_ram_get_used_length(rb);
     return rdma_add_block(opaque, block_name, host_addr, block_offset, length);
 }