Commit 6c97ec5f authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Juan Quintela
Browse files

migration: introduce save_zero_page_to_file 



It will be used by the compression threads

Reviewed-by: default avatarPeter Xu <peterx@redhat.com>
Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: default avatarJuan Quintela <quintela@redhat.com>
Signed-off-by: default avatarJuan Quintela <quintela@redhat.com>
parent 980a19a9

migration/ram.c

+30 −10
Original line number Diff line number Diff line
@@ -1671,6 +1671,31 @@ static void migration_bitmap_sync(RAMState *rs) 
    }

}



/**

 * save_zero_page_to_file: send the zero page to the file

 *

 * Returns the size of data written to the file, 0 means the page is not

 * a zero page

 *

 * @rs: current RAM state

 * @file: the file where the data is saved

 * @block: block that contains the page we want to send

 * @offset: offset inside the block for the page

 */

static int save_zero_page_to_file(RAMState *rs, QEMUFile *file,

                                  RAMBlock *block, ram_addr_t offset)

{

    uint8_t *p = block->host + offset;

    int len = 0;



    if (is_zero_range(p, TARGET_PAGE_SIZE)) {

        len += save_page_header(rs, file, block, offset | RAM_SAVE_FLAG_ZERO);

        qemu_put_byte(file, 0);

        len += 1;

    }

    return len;

}



/**

 * save_zero_page: send the zero page to the stream

 *
@@ -1682,19 +1707,14 @@ static void migration_bitmap_sync(RAMState *rs) 
 */

static int save_zero_page(RAMState *rs, RAMBlock *block, ram_addr_t offset)

{

    uint8_t *p = block->host + offset;

    int pages = -1;

    int len = save_zero_page_to_file(rs, rs->f, block, offset);



    if (is_zero_range(p, TARGET_PAGE_SIZE)) {

    if (len) {

        ram_counters.duplicate++;

        ram_counters.transferred +=

            save_page_header(rs, rs->f, block, offset | RAM_SAVE_FLAG_ZERO);

        qemu_put_byte(rs->f, 0);

        ram_counters.transferred += 1;

        pages = 1;

        ram_counters.transferred += len;

        return 1;

    }



    return pages;

    return -1;

}



static void ram_release_pages(const char *rbname, uint64_t offset, int pages)