[Qemu-trivial] [PATCH-trivial] arch_init.c: Always be sure that 'encoded_buf' and 'current_buf' are lock protected

[Chen Gang <gang.chen.5i5j@gmail.com>]

'encoded_buf' and 'current_buf' are lock protected during using in
save_xbzrle_page() in ram_save_page(), and during freeing in
migration_end().

So recommend to let them lock protected during starting, just like we
have done to 'cache'.


Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
---
 arch_init.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch_init.c b/arch_init.c
index 23044c1..784922c 100644
--- a/arch_init.c
+++ b/arch_init.c
@@ -783,12 +783,12 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
             error_report("Error creating cache");
             return -1;
         }
-        XBZRLE_cache_unlock();

         /* We prefer not to abort if there is no memory */
         XBZRLE.encoded_buf = g_try_malloc0(TARGET_PAGE_SIZE);
         if (!XBZRLE.encoded_buf) {
             error_report("Error allocating encoded_buf");
+            XBZRLE_cache_unlock();
             return -1;
         }

@@ -797,8 +797,10 @@ static int ram_save_setup(QEMUFile *f, void *opaque)
             error_report("Error allocating current_buf");
             g_free(XBZRLE.encoded_buf);
             XBZRLE.encoded_buf = NULL;
+            XBZRLE_cache_unlock();
             return -1;
         }
+        XBZRLE_cache_unlock();

         acct_clear();
     }
-- 
1.7.11.7