diff options
| -rw-r--r-- | kvm-all.c | 53 |
1 files changed, 37 insertions, 16 deletions
@@ -26,6 +26,7 @@ #include "hw/hw.h" #include "gdbstub.h" #include "kvm.h" +#include "bswap.h" /* KVM uses PAGE_SIZE in it's definition of COALESCED_MMIO_MAX */ #define PAGE_SIZE TARGET_PAGE_SIZE @@ -283,11 +284,41 @@ static int kvm_set_migration_log(int enable) return 0; } -static int test_le_bit(unsigned long nr, unsigned char *addr) +/* get kvm's dirty pages bitmap and update qemu's */ +static int kvm_get_dirty_pages_log_range(unsigned long start_addr, + unsigned long *bitmap, + unsigned long offset, + unsigned long mem_size) { - return (addr[nr >> 3] >> (nr & 7)) & 1; + unsigned int i, j; + unsigned long page_number, addr, addr1, c; + ram_addr_t ram_addr; + unsigned int len = ((mem_size / TARGET_PAGE_SIZE) + HOST_LONG_BITS - 1) / + HOST_LONG_BITS; + + /* + * 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; + addr1 = page_number * TARGET_PAGE_SIZE; + addr = offset + addr1; + ram_addr = cpu_get_physical_page_desc(addr); + cpu_physical_memory_set_dirty(ram_addr); + } while (c != 0); + } + } + return 0; } +#define ALIGN(x, y) (((x)+(y)-1) & ~((y)-1)) + /** * kvm_physical_sync_dirty_bitmap - Grab dirty bitmap from kernel space * This function updates qemu's dirty bitmap using cpu_physical_memory_set_dirty(). @@ -301,8 +332,6 @@ static int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr, { KVMState *s = kvm_state; unsigned long size, allocated_size = 0; - target_phys_addr_t phys_addr; - ram_addr_t addr; KVMDirtyLog d; KVMSlot *mem; int ret = 0; @@ -314,7 +343,7 @@ static int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr, break; } - size = ((mem->memory_size >> TARGET_PAGE_BITS) + 7) / 8; + size = ALIGN(((mem->memory_size) >> TARGET_PAGE_BITS), HOST_LONG_BITS) / 8; if (!d.dirty_bitmap) { d.dirty_bitmap = qemu_malloc(size); } else if (size > allocated_size) { @@ -331,17 +360,9 @@ static int kvm_physical_sync_dirty_bitmap(target_phys_addr_t start_addr, break; } - for (phys_addr = mem->start_addr, addr = mem->phys_offset; - phys_addr < mem->start_addr + mem->memory_size; - phys_addr += TARGET_PAGE_SIZE, addr += TARGET_PAGE_SIZE) { - unsigned char *bitmap = (unsigned char *)d.dirty_bitmap; - unsigned nr = (phys_addr - mem->start_addr) >> TARGET_PAGE_BITS; - - if (test_le_bit(nr, bitmap)) { - cpu_physical_memory_set_dirty(addr); - } - } - start_addr = phys_addr; + kvm_get_dirty_pages_log_range(mem->start_addr, d.dirty_bitmap, + mem->start_addr, mem->memory_size); + start_addr = mem->start_addr + mem->memory_size; } qemu_free(d.dirty_bitmap); |