Re: [Qemu-devel] [PATCH 11/11] Restart optimization on stage3 update version

[Vinod, Chegu]

 

 

-----Original Message-----
From: Orit Wasserman [mailto:address@hidden

 

From: Juan Quintela <address@hidden>

 

Signed-off-by: Juan Quintela <address@hidden>

---

arch_init.c |   24 +++++++++++++++---------

1 files changed, 15 insertions(+), 9 deletions(-)

 

diff --git a/arch_init.c b/arch_init.c

index f484bd5..f555c27 100644

--- a/arch_init.c

+++ b/arch_init.c

@@ -279,7 +279,7 @@ static void save_block_hdr(QEMUFile *f, RAMBlock *block, ram_addr_t offset,

 static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,

                             ram_addr_t current_addr, RAMBlock *block,

-                            ram_addr_t offset, int cont)

+                            ram_addr_t offset, int cont, bool

+ last_stage)

{

     int encoded_len = 0, bytes_sent = -1;

     XBZRLEHeader hdr = {

@@ -289,8 +289,10 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,

     uint8_t *prev_cached_page;

     if (!cache_is_cached(XBZRLE.cache, current_addr)) {

-        cache_insert(XBZRLE.cache, current_addr,

-                     g_memdup(current_data, TARGET_PAGE_SIZE));

+        if (!last_stage) {

+            cache_insert(XBZRLE.cache, current_addr,

+                         g_memdup(current_data, TARGET_PAGE_SIZE));

+        }

         acct_info.xbzrle_cache_miss++;

         return -1;

     }

@@ -317,7 +319,9 @@ static int save_xbzrle_page(QEMUFile *f, uint8_t *current_data,

     /* we need to update the data in the cache, in order to get the same data

        we cached we decode the encoded page on the cached data */

 

Nit :  Are the above comments still valid…given that there is no decoding happening here ?

 

-    memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);

+    if (!last_stage) {

+        memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);

+    }

     hdr.xh_len = encoded_len;

     hdr.xh_flags |= ENCODING_FLAG_XBZRLE; @@ -345,7 +349,7 @@ static ram_addr_t last_offset;

  *           n: the amount of bytes written in other case

  */

-static int ram_save_block(QEMUFile *f)

+static int ram_save_block(QEMUFile *f, bool last_stage)

{

     RAMBlock *block = last_block;

     ram_addr_t offset = last_offset;

@@ -376,8 +380,10 @@ static int ram_save_block(QEMUFile *f)

             } else if (migrate_use_xbzrle()) {

                 current_addr = block->offset + offset;

                 bytes_sent = save_xbzrle_page(f, p, current_addr, block,

-                                              offset, cont);

-                p = get_cached_data(XBZRLE.cache, current_addr);

+                                              offset, cont, last_stage);

+                if (!last_stage) {

+                    p = get_cached_data(XBZRLE.cache, current_addr);

+                }

             }

             /* either we didn't send yet (we may have had XBZRLE overflow) */ @@ -549,7 +555,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque)

     while ((ret = qemu_file_rate_limit(f)) == 0) {

         int bytes_sent;

-        bytes_sent = ram_save_block(f);

+        bytes_sent = ram_save_block(f, false);

         /* no more blocks to sent */

         if (bytes_sent < 0) {

             break;

@@ -611,7 +617,7 @@ static int ram_save_complete(QEMUFile *f, void *opaque)

     while (true) {

         int bytes_sent;

-        bytes_sent = ram_save_block(f);

+        bytes_sent = ram_save_block(f, true);

         /* no more blocks to sent */

         if (bytes_sent < 0) {

             break;

--

1.7.7.6