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: Wei Wang <wei.w.wang@intel.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Xiao Guangrong <xiaoguangrong@tencent.com>
Message-Id: <20180330075128.26919-2-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
Xiao Guangrong 2018-03-30 15:51:19 +08:00 committed by Dr. David Alan Gilbert
parent 65ace06045
commit 263a289ae6

View File

@ -1137,7 +1137,7 @@ static int ram_save_compressed_page(RAMState *rs, PageSearchStatus *pss,
int pages = -1; int pages = -1;
uint64_t bytes_xmit = 0; uint64_t bytes_xmit = 0;
uint8_t *p; uint8_t *p;
int ret, blen; int ret;
RAMBlock *block = pss->block; RAMBlock *block = pss->block;
ram_addr_t offset = pss->page << TARGET_PAGE_BITS; 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) { if (block != rs->last_sent_block) {
flush_compressed_data(rs); flush_compressed_data(rs);
pages = save_zero_page(rs, block, offset); 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) { if (pages > 0) {
ram_release_pages(block->idstr, offset, pages); 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 { } else {
pages = save_zero_page(rs, block, offset); pages = save_zero_page(rs, block, offset);