[Qemu-devel] [PATCH] xbzrle: don't check the value in the vm ram repeatedly

[arei.gonglei]

From: ChenLiang <address@hidden>

xbzrle_encode_buffer checks the value in the ram repeatedly.
It is risk if runs xbzrle_encode_buffer on changing data.
And it is not necessary.

Reported-by: Dr. David Alan Gilbert <address@hidden>
Signed-off-by: ChenLiang <address@hidden>
Signed-off-by: Gonglei <address@hidden>
---
 xbzrle.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/xbzrle.c b/xbzrle.c
index fbcb35d..e2c7595 100644
--- a/xbzrle.c
+++ b/xbzrle.c
@@ -82,6 +82,8 @@ int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t *new_buf, 
int slen,
         if (d + 2 > dlen) {
             return -1;
         }
+        i++;
+        nzrun_len++;
         /* not aligned to sizeof(long) */
         res = (slen - i) % sizeof(long);
         while (res && old_buf[i] != new_buf[i]) {
@@ -118,6 +120,8 @@ int xbzrle_encode_buffer(uint8_t *old_buf, uint8_t 
*new_buf, int slen,
         memcpy(dst + d, nzrun_start, nzrun_len);
         d += nzrun_len;
         nzrun_len = 0;
+        i++;
+        zrun_len++;
     }
 
     return d;
-- 
1.7.12.4