This reverts commit ae2810c4bb3b383176e8e1b33931b16c01483aab.
This reverts the optimization introduced by the original patch as
it breaks dirty page tracking on systems where
getpagesize() != TARGET_PAGE_SIZE such as POWERPC64.
The cpu_physical_memory_set_dirty_lebitmap() is called from
the kvm_physical_sync_dirty_bitmap() with the bitmap returned by
the KVM's KVM_GET_DIRTY_LOG ioctl where 1 bit is per the system
page. However QEMU's ram_list.dirty_memory maps are allocated to store
1 bit per TARGET_PAGE_SIZE which is hardcoded to 4K.
Since 64K system page size is quite popular configuration on PPC64,
the original patch breaks migration.
Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
include/exec/ram_addr.h | 54 +++++++++++++++++--------------------------------
1 file changed, 18 insertions(+), 36 deletions(-)
diff --git a/include/exec/ram_addr.h b/include/exec/ram_addr.h
index 33c8acc..c6736ed 100644
--- a/include/exec/ram_addr.h
+++ b/include/exec/ram_addr.h
@@ -83,47 +83,29 @@ static inline void
cpu_physical_memory_set_dirty_lebitmap(unsigned long *bitmap,
ram_addr_t start,
ram_addr_t pages)
{
- unsigned long i, j;
+ unsigned int i, j;
unsigned long page_number, c;
hwaddr addr;
ram_addr_t ram_addr;
- unsigned long len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
+ unsigned int len = (pages + HOST_LONG_BITS - 1) / HOST_LONG_BITS;
unsigned long hpratio = getpagesize() / TARGET_PAGE_SIZE;
- unsigned long page = BIT_WORD(start >> TARGET_PAGE_BITS);
- /* start address is aligned at the start of a word? */
- if (((page * BITS_PER_LONG) << TARGET_PAGE_BITS) == start) {
- long k;
- long nr = BITS_TO_LONGS(pages);
-
- for (k = 0; k < nr; k++) {
- if (bitmap[k]) {
- unsigned long temp = leul_to_cpu(bitmap[k]);
-
- ram_list.dirty_memory[DIRTY_MEMORY_MIGRATION][page + k] |=
temp;
- ram_list.dirty_memory[DIRTY_MEMORY_VGA][page + k] |= temp;
- ram_list.dirty_memory[DIRTY_MEMORY_CODE][page + k] |= temp;
- }
- }
- xen_modified_memory(start, pages);
- } else {
- /*
- * bitmap-traveling is faster than memory-traveling (for addr...)
- * especially when most of the memory is not dirty.
- */
- for (i = 0; i < len; i++) {
- if (bitmap[i] != 0) {
- c = leul_to_cpu(bitmap[i]);
- do {
- j = ffsl(c) - 1;
- c &= ~(1ul << j);
- page_number = (i * HOST_LONG_BITS + j) * hpratio;
- addr = page_number * TARGET_PAGE_SIZE;
- ram_addr = start + addr;
- cpu_physical_memory_set_dirty_range(ram_addr,
- TARGET_PAGE_SIZE * hpratio);
- } while (c != 0);
- }
+ /*
+ * bitmap-traveling is faster than memory-traveling (for addr...)
+ * especially when most of the memory is not dirty.
+ */
+ for (i = 0; i < len; i++) {
+ if (bitmap[i] != 0) {
+ c = leul_to_cpu(bitmap[i]);
+ do {
+ j = ffsl(c) - 1;
+ c &= ~(1ul << j);
+ page_number = (i * HOST_LONG_BITS + j) * hpratio;
+ addr = page_number * TARGET_PAGE_SIZE;
+ ram_addr = start + addr;
+ cpu_physical_memory_set_dirty_range(ram_addr,
+ TARGET_PAGE_SIZE *
hpratio);
+ } while (c != 0);
}
}
}
--
1.8.4.rc4
