Merge remote-tracking branch 'quintela/migration.next' into staging

# By Peter Lieven (9) and others
# Via Juan Quintela
* quintela/migration.next: (22 commits)
  Use qemu_put_buffer_async for guest memory pages
  Add qemu_put_buffer_async
  Use writev ops if available
  Store the data to send also in iovec
  Update bytes_xfer in qemu_put_byte
  Add socket_writev_buffer function
  Add QemuFileWritevBuffer QemuFileOps
  migration: use XBZRLE only after bulk stage
  migration: do not search dirty pages in bulk stage
  migration: do not sent zero pages in bulk stage
  migration: add an indicator for bulk state of ram migration
  migration: search for zero instead of dup pages
  bitops: unroll while loop in find_next_bit()
  buffer_is_zero: use vector optimizations if possible
  cutils: add a function to find non-zero content in a buffer
  move vector definitions to qemu-common.h
  savevm: Fix bugs in the VMSTATE_VBUFFER_MULTIPLY definition
  savevm: Add VMSTATE_STRUCT_VARRAY_POINTER_UINT32
  savevm: Add VMSTATE_FLOAT64 helpers
  savevm: Add VMSTATE_UINTTL_EQUAL helper
  ...

1 files changed, 17 insertions, 1 deletions

diff --git a/util/bitops.c b/util/bitops.c
index e72237ab2b..227c38b883 100644
--- a/util/bitops.c
+++ b/util/bitops.c
@@ -42,7 +42,23 @@ unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
         size -= BITS_PER_LONG;
         result += BITS_PER_LONG;
     }
-    while (size & ~(BITS_PER_LONG-1)) {
+    while (size >= 4*BITS_PER_LONG) {
+        unsigned long d1, d2, d3;
+        tmp = *p;
+        d1 = *(p+1);
+        d2 = *(p+2);
+        d3 = *(p+3);
+        if (tmp) {
+            goto found_middle;
+        }
+        if (d1 | d2 | d3) {
+            break;
+        }
+        p += 4;
+        result += 4*BITS_PER_LONG;
+        size -= 4*BITS_PER_LONG;
+    }
+    while (size >= BITS_PER_LONG) {
         if ((tmp = *(p++))) {
             goto found_middle;
         }