Commit 263a289a authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Dr. David Alan Gilbert
Browse files

migration: stop compressing page in migration thread 



As compression is a heavy work, do not do it in migration thread,
instead, we post it out as a normal page

Reviewed-by: default avatarWei Wang <wei.w.wang@intel.com>
Reviewed-by: default avatarPeter Xu <peterx@redhat.com>
Reviewed-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-2-xiaoguangrong@tencent.com>
Signed-off-by: default avatarDr. David Alan Gilbert <dgilbert@redhat.com>
parent 65ace060

migration/ram.c

+16 −16
Original line number Diff line number Diff line
@@ -1137,7 +1137,7 @@ static int ram_save_compressed_page(RAMState *rs, PageSearchStatus *pss, 
    int pages = -1;

    uint64_t bytes_xmit = 0;

    uint8_t *p;

    int ret, blen;

    int ret;

    RAMBlock *block = pss->block;

    ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
@@ -1167,23 +1167,23 @@ static int ram_save_compressed_page(RAMState *rs, PageSearchStatus *pss, 
        if (block != rs->last_sent_block) {

            flush_compressed_data(rs);

            pages = save_zero_page(rs, block, offset);

            if (pages == -1) {

                /* Make sure the first page is sent out before other pages */

                bytes_xmit = save_page_header(rs, rs->f, block, offset |

                                              RAM_SAVE_FLAG_COMPRESS_PAGE);

                blen = qemu_put_compression_data(rs->f, p, TARGET_PAGE_SIZE,

                                                 migrate_compress_level());

                if (blen > 0) {

                    ram_counters.transferred += bytes_xmit + blen;

                    ram_counters.normal++;

                    pages = 1;

                } else {

                    qemu_file_set_error(rs->f, blen);

                    error_report("compressed data failed!");

                }

            }

            if (pages > 0) {

                ram_release_pages(block->idstr, offset, pages);

            } else {

                /*

                 * Make sure the first page is sent out before other pages.

                 *

                 * we post it as normal page as compression will take much

                 * CPU resource.

                 */

                ram_counters.transferred += save_page_header(rs, rs->f, block,

                                                offset | RAM_SAVE_FLAG_PAGE);

                qemu_put_buffer_async(rs->f, p, TARGET_PAGE_SIZE,

                                      migrate_release_ram() &

                                      migration_in_postcopy());

                ram_counters.transferred += TARGET_PAGE_SIZE;

                ram_counters.normal++;

                pages = 1;

            }

        } else {

            pages = save_zero_page(rs, block, offset);