migration: introduce control_save_page()

Abstract the common function control_save_page() to cleanup the code,
no logic is changed

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: <20180330075128.26919-6-xiaoguangrong@tencent.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
This commit is contained in:
Xiao Guangrong 2018-03-30 15:51:23 +08:00 committed by Dr. David Alan Gilbert
parent 34ab9e9743
commit 059ff0fb29

View file

@ -974,6 +974,44 @@ static void ram_release_pages(const char *rbname, uint64_t offset, int pages)
ram_discard_range(rbname, offset, pages << TARGET_PAGE_BITS);
}
/*
* @pages: the number of pages written by the control path,
* < 0 - error
* > 0 - number of pages written
*
* Return true if the pages has been saved, otherwise false is returned.
*/
static bool control_save_page(RAMState *rs, RAMBlock *block, ram_addr_t offset,
int *pages)
{
uint64_t bytes_xmit = 0;
int ret;
*pages = -1;
ret = ram_control_save_page(rs->f, block->offset, offset, TARGET_PAGE_SIZE,
&bytes_xmit);
if (ret == RAM_SAVE_CONTROL_NOT_SUPP) {
return false;
}
if (bytes_xmit) {
ram_counters.transferred += bytes_xmit;
*pages = 1;
}
if (ret == RAM_SAVE_CONTROL_DELAYED) {
return true;
}
if (bytes_xmit > 0) {
ram_counters.normal++;
} else if (bytes_xmit == 0) {
ram_counters.duplicate++;
}
return true;
}
/**
* ram_save_page: send the given page to the stream
*
@ -990,56 +1028,36 @@ static void ram_release_pages(const char *rbname, uint64_t offset, int pages)
static int ram_save_page(RAMState *rs, PageSearchStatus *pss, bool last_stage)
{
int pages = -1;
uint64_t bytes_xmit;
ram_addr_t current_addr;
uint8_t *p;
int ret;
bool send_async = true;
RAMBlock *block = pss->block;
ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
ram_addr_t current_addr = block->offset + offset;
p = block->host + offset;
trace_ram_save_page(block->idstr, (uint64_t)offset, p);
/* In doubt sent page as normal */
bytes_xmit = 0;
ret = ram_control_save_page(rs->f, block->offset,
offset, TARGET_PAGE_SIZE, &bytes_xmit);
if (bytes_xmit) {
ram_counters.transferred += bytes_xmit;
pages = 1;
if (control_save_page(rs, block, offset, &pages)) {
return pages;
}
XBZRLE_cache_lock();
current_addr = block->offset + offset;
if (ret != RAM_SAVE_CONTROL_NOT_SUPP) {
if (ret != RAM_SAVE_CONTROL_DELAYED) {
if (bytes_xmit > 0) {
ram_counters.normal++;
} else if (bytes_xmit == 0) {
ram_counters.duplicate++;
}
}
} else {
pages = save_zero_page(rs, block, offset);
if (pages > 0) {
/* Must let xbzrle know, otherwise a previous (now 0'd) cached
* page would be stale
pages = save_zero_page(rs, block, offset);
if (pages > 0) {
/* Must let xbzrle know, otherwise a previous (now 0'd) cached
* page would be stale
*/
xbzrle_cache_zero_page(rs, current_addr);
ram_release_pages(block->idstr, offset, pages);
} else if (!rs->ram_bulk_stage &&
!migration_in_postcopy() && migrate_use_xbzrle()) {
pages = save_xbzrle_page(rs, &p, current_addr, block,
offset, last_stage);
if (!last_stage) {
/* Can't send this cached data async, since the cache page
* might get updated before it gets to the wire
*/
xbzrle_cache_zero_page(rs, current_addr);
ram_release_pages(block->idstr, offset, pages);
} else if (!rs->ram_bulk_stage &&
!migration_in_postcopy() && migrate_use_xbzrle()) {
pages = save_xbzrle_page(rs, &p, current_addr, block,
offset, last_stage);
if (!last_stage) {
/* Can't send this cached data async, since the cache page
* might get updated before it gets to the wire
*/
send_async = false;
}
send_async = false;
}
}
@ -1174,63 +1192,49 @@ static int ram_save_compressed_page(RAMState *rs, PageSearchStatus *pss,
bool last_stage)
{
int pages = -1;
uint64_t bytes_xmit = 0;
uint8_t *p;
int ret;
RAMBlock *block = pss->block;
ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
p = block->host + offset;
ret = ram_control_save_page(rs->f, block->offset,
offset, TARGET_PAGE_SIZE, &bytes_xmit);
if (bytes_xmit) {
ram_counters.transferred += bytes_xmit;
pages = 1;
if (control_save_page(rs, block, offset, &pages)) {
return pages;
}
if (ret != RAM_SAVE_CONTROL_NOT_SUPP) {
if (ret != RAM_SAVE_CONTROL_DELAYED) {
if (bytes_xmit > 0) {
ram_counters.normal++;
} else if (bytes_xmit == 0) {
ram_counters.duplicate++;
}
/* When starting the process of a new block, the first page of
* the block should be sent out before other pages in the same
* block, and all the pages in last block should have been sent
* out, keeping this order is important, because the 'cont' flag
* is used to avoid resending the block name.
*/
if (block != rs->last_sent_block) {
flush_compressed_data(rs);
pages = save_zero_page(rs, block, offset);
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 {
/* When starting the process of a new block, the first page of
* the block should be sent out before other pages in the same
* block, and all the pages in last block should have been sent
* out, keeping this order is important, because the 'cont' flag
* is used to avoid resending the block name.
*/
if (block != rs->last_sent_block) {
flush_compressed_data(rs);
pages = save_zero_page(rs, block, offset);
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;
}
pages = save_zero_page(rs, block, offset);
if (pages == -1) {
pages = compress_page_with_multi_thread(rs, block, offset);
} else {
pages = save_zero_page(rs, block, offset);
if (pages == -1) {
pages = compress_page_with_multi_thread(rs, block, offset);
} else {
ram_release_pages(block->idstr, offset, pages);
}
ram_release_pages(block->idstr, offset, pages);
}
}