@@ -47,6 +47,8 @@ struct RAMBlock {
* of the postcopy phase
*/
unsigned long *unsentmap;
+ /* bitmap of already received pages in postcopy */
+ unsigned long *receivedmap;
};
static inline bool offset_in_ramblock(RAMBlock *b, ram_addr_t offset)
@@ -60,6 +62,14 @@ static inline void *ramblock_ptr(RAMBlock *block, ram_addr_t offset)
return (char *)block->host + offset;
}
+static inline unsigned long int ramblock_recv_bitmap_offset(void *host_addr,
+ RAMBlock *rb)
+{
+ uint64_t host_addr_offset =
+ (uint64_t)(uintptr_t)(host_addr - (void *)rb->host);
+ return host_addr_offset >> TARGET_PAGE_BITS;
+}
+
long qemu_getrampagesize(void);
unsigned long last_ram_page(void);
RAMBlock *qemu_ram_alloc_from_file(ram_addr_t size, MemoryRegion *mr,
@@ -363,6 +363,7 @@ void migration_fd_process_incoming(QEMUFile *f)
Coroutine *co = qemu_coroutine_create(process_incoming_migration_co, f);
qemu_file_set_blocking(f, false);
+ ramblock_recv_map_init();
qemu_coroutine_enter(co);
}
@@ -562,22 +562,27 @@ int postcopy_ram_enable_notify(MigrationIncomingState *mis)
}
static int qemu_ufd_copy_ioctl(int userfault_fd, void *host_addr,
- void *from_addr, uint64_t pagesize)
+ void *from_addr, uint64_t pagesize, RAMBlock *rb)
{
+ int ret;
if (from_addr) {
struct uffdio_copy copy_struct;
copy_struct.dst = (uint64_t)(uintptr_t)host_addr;
copy_struct.src = (uint64_t)(uintptr_t)from_addr;
copy_struct.len = pagesize;
copy_struct.mode = 0;
- return ioctl(userfault_fd, UFFDIO_COPY, ©_struct);
+ ret = ioctl(userfault_fd, UFFDIO_COPY, ©_struct);
} else {
struct uffdio_zeropage zero_struct;
zero_struct.range.start = (uint64_t)(uintptr_t)host_addr;
zero_struct.range.len = pagesize;
zero_struct.mode = 0;
- return ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
+ ret = ioctl(userfault_fd, UFFDIO_ZEROPAGE, &zero_struct);
+ }
+ if (!ret) {
+ ramblock_recv_bitmap_set(host_addr, rb);
}
+ return ret;
}
/*
@@ -594,7 +599,7 @@ int postcopy_place_page(MigrationIncomingState *mis, void *host, void *from,
* which would be slightly cheaper, but we'd have to be careful
* of the order of updating our page state.
*/
- if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize)) {
+ if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, from, pagesize, rb)) {
int e = errno;
error_report("%s: %s copy host: %p from: %p (size: %zd)",
__func__, strerror(e), host, from, pagesize);
@@ -616,7 +621,8 @@ int postcopy_place_page_zero(MigrationIncomingState *mis, void *host,
trace_postcopy_place_page_zero(host);
if (qemu_ram_pagesize(rb) == getpagesize()) {
- if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize())) {
+ if (qemu_ufd_copy_ioctl(mis->userfault_fd, host, NULL, getpagesize(),
+ rb)) {
int e = errno;
error_report("%s: %s zero host: %p",
__func__, strerror(e), host);
@@ -151,6 +151,32 @@ out:
return ret;
}
+void ramblock_recv_map_init(void)
+{
+ RAMBlock *rb;
+
+ RAMBLOCK_FOREACH(rb) {
+ assert(!rb->receivedmap);
+ rb->receivedmap = bitmap_new(rb->max_length >> TARGET_PAGE_BITS);
+ }
+}
+
+int ramblock_recv_bitmap_test(void *host_addr, RAMBlock *rb)
+{
+ return test_bit(ramblock_recv_bitmap_offset(host_addr, rb),
+ rb->receivedmap);
+}
+
+void ramblock_recv_bitmap_set(void *host_addr, RAMBlock *rb)
+{
+ set_bit_atomic(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
+}
+
+void ramblock_recv_bitmap_clear(void *host_addr, RAMBlock *rb)
+{
+ clear_bit(ramblock_recv_bitmap_offset(host_addr, rb), rb->receivedmap);
+}
+
/*
* An outstanding page request, on the source, having been received
* and queued
@@ -1797,6 +1823,8 @@ int ram_discard_range(const char *rbname, uint64_t start, size_t length)
goto err;
}
+ bitmap_clear(rb->receivedmap, start >> TARGET_PAGE_BITS,
+ length >> TARGET_PAGE_BITS);
ret = ram_block_discard_range(rb, start, length);
err:
@@ -2324,8 +2352,14 @@ static int ram_load_setup(QEMUFile *f, void *opaque)
static int ram_load_cleanup(void *opaque)
{
+ RAMBlock *rb;
xbzrle_load_cleanup();
compress_threads_load_cleanup();
+
+ RAMBLOCK_FOREACH(rb) {
+ g_free(rb->receivedmap);
+ rb->receivedmap = NULL;
+ }
return 0;
}
@@ -2513,6 +2547,7 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
ram_addr_t addr, total_ram_bytes;
void *host = NULL;
uint8_t ch;
+ RAMBlock *rb = NULL;
addr = qemu_get_be64(f);
flags = addr & ~TARGET_PAGE_MASK;
@@ -2520,15 +2555,16 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id)
if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE |
RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) {
- RAMBlock *block = ram_block_from_stream(f, flags);
+ rb = ram_block_from_stream(f, flags);
- host = host_from_ram_block_offset(block, addr);
+ host = host_from_ram_block_offset(rb, addr);
if (!host) {
error_report("Illegal RAM offset " RAM_ADDR_FMT, addr);
ret = -EINVAL;
break;
}
- trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host);
+ ramblock_recv_bitmap_set(host, rb);
+ trace_ram_load_loop(rb->idstr, (uint64_t)addr, flags, host);
}
switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
@@ -52,4 +52,10 @@ int ram_discard_range(const char *block_name, uint64_t start, size_t length);
int ram_postcopy_incoming_init(MigrationIncomingState *mis);
void ram_handle_compressed(void *host, uint8_t ch, uint64_t size);
+
+void ramblock_recv_map_init(void);
+int ramblock_recv_bitmap_test(void *host_addr, RAMBlock *rb);
+void ramblock_recv_bitmap_set(void *host_addr, RAMBlock *rb);
+void ramblock_recv_bitmap_clear(void *host_addr, RAMBlock *rb);
+
#endif
This patch adds ability to track down already received pages, it's necessary for calculation vCPU block time in postcopy migration feature, maybe for restore after postcopy migration failure. Also it's necessary to solve shared memory issue in postcopy livemigration. Information about received pages will be transferred to the software virtual bridge (e.g. OVS-VSWITCHD), to avoid fallocate (unmap) for already received pages. fallocate syscall is required for remmaped shared memory, due to remmaping itself blocks ioctl(UFFDIO_COPY, ioctl in this case will end with EEXIT error (struct page is exists after remmap). Bitmap is placed into RAMBlock as another postcopy/precopy related bitmaps. Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com> --- include/exec/ram_addr.h | 10 ++++++++++ migration/migration.c | 1 + migration/postcopy-ram.c | 16 +++++++++++----- migration/ram.c | 42 +++++++++++++++++++++++++++++++++++++++--- migration/ram.h | 6 ++++++ 5 files changed, 67 insertions(+), 8 deletions(-)