migration: introduce save_zero_page_to_file

It will be used by the compression threads

Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
This commit is contained in:
Xiao Guangrong 2018-08-21 16:10:22 +08:00 committed by Juan Quintela
parent 980a19a929
commit 6c97ec5f5a

View File

@ -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)