#include "qemu/bitmap.h"
#include "qemu/timer.h"
#include "qemu/main-loop.h"
+#include "xbzrle.h"
#include "migration/migration.h"
-#include "migration/postcopy-ram.h"
+#include "migration/qemu-file.h"
+#include "migration/vmstate.h"
+#include "postcopy-ram.h"
#include "exec/address-spaces.h"
#include "migration/page_cache.h"
#include "qemu/error-report.h"
#include "qemu/rcu_queue.h"
#include "migration/colo.h"
-static int dirty_rate_high_cnt;
-
-static uint64_t bitmap_sync_count;
-
/***********************************************************/
/* ram save/restore */
+/* RAM_SAVE_FLAG_ZERO used to be named RAM_SAVE_FLAG_COMPRESS, it
+ * worked for pages that where filled with the same char. We switched
+ * it to only search for the zero value. And to avoid confusion with
+ * RAM_SSAVE_FLAG_COMPRESS_PAGE just rename it.
+ */
+
#define RAM_SAVE_FLAG_FULL 0x01 /* Obsolete, not used anymore */
-#define RAM_SAVE_FLAG_COMPRESS 0x02
+#define RAM_SAVE_FLAG_ZERO 0x02
#define RAM_SAVE_FLAG_MEM_SIZE 0x04
#define RAM_SAVE_FLAG_PAGE 0x08
#define RAM_SAVE_FLAG_EOS 0x10
qemu_mutex_unlock(&XBZRLE.lock);
}
-/*
- * called from qmp_migrate_set_cache_size in main thread, possibly while
- * a migration is in progress.
- * A running migration maybe using the cache and might finish during this
- * call, hence changes to the cache are protected by XBZRLE.lock().
+/**
+ * xbzrle_cache_resize: resize the xbzrle cache
+ *
+ * This function is called from qmp_migrate_set_cache_size in main
+ * thread, possibly while a migration is in progress. A running
+ * migration may be using the cache and might finish during this call,
+ * hence changes to the cache are protected by XBZRLE.lock().
+ *
+ * Returns the new_size or negative in case of error.
+ *
+ * @new_size: new cache size
*/
int64_t xbzrle_cache_resize(int64_t new_size)
{
return ret;
}
-/* accounting for migration statistics */
-typedef struct AccountingInfo {
- uint64_t dup_pages;
- uint64_t skipped_pages;
+/*
+ * An outstanding page request, on the source, having been received
+ * and queued
+ */
+struct RAMSrcPageRequest {
+ RAMBlock *rb;
+ hwaddr offset;
+ hwaddr len;
+
+ QSIMPLEQ_ENTRY(RAMSrcPageRequest) next_req;
+};
+
+/* State of RAM for migration */
+struct RAMState {
+ /* QEMUFile used for this migration */
+ QEMUFile *f;
+ /* Last block that we have visited searching for dirty pages */
+ RAMBlock *last_seen_block;
+ /* Last block from where we have sent data */
+ RAMBlock *last_sent_block;
+ /* Last dirty target page we have sent */
+ ram_addr_t last_page;
+ /* last ram version we have seen */
+ uint32_t last_version;
+ /* We are in the first round */
+ bool ram_bulk_stage;
+ /* How many times we have dirty too many pages */
+ int dirty_rate_high_cnt;
+ /* How many times we have synchronized the bitmap */
+ uint64_t bitmap_sync_count;
+ /* these variables are used for bitmap sync */
+ /* last time we did a full bitmap_sync */
+ int64_t time_last_bitmap_sync;
+ /* bytes transferred at start_time */
+ uint64_t bytes_xfer_prev;
+ /* number of dirty pages since start_time */
+ uint64_t num_dirty_pages_period;
+ /* xbzrle misses since the beginning of the period */
+ uint64_t xbzrle_cache_miss_prev;
+ /* number of iterations at the beginning of period */
+ uint64_t iterations_prev;
+ /* Accounting fields */
+ /* number of zero pages. It used to be pages filled by the same char. */
+ uint64_t zero_pages;
+ /* number of normal transferred pages */
uint64_t norm_pages;
+ /* Iterations since start */
uint64_t iterations;
+ /* xbzrle transmitted bytes. Notice that this is with
+ * compression, they can't be calculated from the pages */
uint64_t xbzrle_bytes;
+ /* xbzrle transmmited pages */
uint64_t xbzrle_pages;
+ /* xbzrle number of cache miss */
uint64_t xbzrle_cache_miss;
+ /* xbzrle miss rate */
double xbzrle_cache_miss_rate;
+ /* xbzrle number of overflows */
uint64_t xbzrle_overflows;
-} AccountingInfo;
+ /* number of dirty bits in the bitmap */
+ uint64_t migration_dirty_pages;
+ /* total number of bytes transferred */
+ uint64_t bytes_transferred;
+ /* number of dirtied pages in the last second */
+ uint64_t dirty_pages_rate;
+ /* Count of requests incoming from destination */
+ uint64_t postcopy_requests;
+ /* protects modification of the bitmap */
+ QemuMutex bitmap_mutex;
+ /* The RAMBlock used in the last src_page_requests */
+ RAMBlock *last_req_rb;
+ /* Queue of outstanding page requests from the destination */
+ QemuMutex src_page_req_mutex;
+ QSIMPLEQ_HEAD(src_page_requests, RAMSrcPageRequest) src_page_requests;
+};
+typedef struct RAMState RAMState;
-static AccountingInfo acct_info;
+static RAMState ram_state;
-static void acct_clear(void)
+uint64_t dup_mig_pages_transferred(void)
{
- memset(&acct_info, 0, sizeof(acct_info));
+ return ram_state.zero_pages;
}
-uint64_t dup_mig_bytes_transferred(void)
+uint64_t norm_mig_pages_transferred(void)
{
- return acct_info.dup_pages * TARGET_PAGE_SIZE;
+ return ram_state.norm_pages;
}
-uint64_t dup_mig_pages_transferred(void)
+uint64_t xbzrle_mig_bytes_transferred(void)
{
- return acct_info.dup_pages;
+ return ram_state.xbzrle_bytes;
}
-uint64_t skipped_mig_bytes_transferred(void)
+uint64_t xbzrle_mig_pages_transferred(void)
{
- return acct_info.skipped_pages * TARGET_PAGE_SIZE;
+ return ram_state.xbzrle_pages;
}
-uint64_t skipped_mig_pages_transferred(void)
+uint64_t xbzrle_mig_pages_cache_miss(void)
{
- return acct_info.skipped_pages;
+ return ram_state.xbzrle_cache_miss;
}
-uint64_t norm_mig_bytes_transferred(void)
+double xbzrle_mig_cache_miss_rate(void)
{
- return acct_info.norm_pages * TARGET_PAGE_SIZE;
+ return ram_state.xbzrle_cache_miss_rate;
}
-uint64_t norm_mig_pages_transferred(void)
+uint64_t xbzrle_mig_pages_overflow(void)
{
- return acct_info.norm_pages;
+ return ram_state.xbzrle_overflows;
}
-uint64_t xbzrle_mig_bytes_transferred(void)
+uint64_t ram_bytes_transferred(void)
{
- return acct_info.xbzrle_bytes;
+ return ram_state.bytes_transferred;
}
-uint64_t xbzrle_mig_pages_transferred(void)
+uint64_t ram_bytes_remaining(void)
{
- return acct_info.xbzrle_pages;
+ return ram_state.migration_dirty_pages * TARGET_PAGE_SIZE;
}
-uint64_t xbzrle_mig_pages_cache_miss(void)
+uint64_t ram_dirty_sync_count(void)
{
- return acct_info.xbzrle_cache_miss;
+ return ram_state.bitmap_sync_count;
}
-double xbzrle_mig_cache_miss_rate(void)
+uint64_t ram_dirty_pages_rate(void)
{
- return acct_info.xbzrle_cache_miss_rate;
+ return ram_state.dirty_pages_rate;
}
-uint64_t xbzrle_mig_pages_overflow(void)
+uint64_t ram_postcopy_requests(void)
{
- return acct_info.xbzrle_overflows;
+ return ram_state.postcopy_requests;
}
-/* This is the last block that we have visited serching for dirty pages
- */
-static RAMBlock *last_seen_block;
-/* This is the last block from where we have sent data */
-static RAMBlock *last_sent_block;
-static ram_addr_t last_offset;
-static QemuMutex migration_bitmap_mutex;
-static uint64_t migration_dirty_pages;
-static uint32_t last_version;
-static bool ram_bulk_stage;
-
/* used by the search for pages to send */
struct PageSearchStatus {
/* Current block being searched */
RAMBlock *block;
- /* Current offset to search from */
- ram_addr_t offset;
+ /* Current page to search from */
+ unsigned long page;
/* Set once we wrap around */
bool complete_round;
};
typedef struct PageSearchStatus PageSearchStatus;
-static struct BitmapRcu {
- struct rcu_head rcu;
- /* Main migration bitmap */
- unsigned long *bmap;
- /* bitmap of pages that haven't been sent even once
- * only maintained and used in postcopy at the moment
- * where it's used to send the dirtymap at the start
- * of the postcopy phase
- */
- unsigned long *unsentmap;
-} *migration_bitmap_rcu;
-
struct CompressParam {
bool done;
bool quit;
/* The empty QEMUFileOps will be used by file in CompressParam */
static const QEMUFileOps empty_ops = { };
-static bool compression_switch;
static DecompressParam *decomp_param;
static QemuThread *decompress_threads;
static QemuMutex decomp_done_lock;
int idx, thread_count;
thread_count = migrate_compress_threads();
+
for (idx = 0; idx < thread_count; idx++) {
qemu_mutex_lock(&comp_param[idx].mutex);
comp_param[idx].quit = true;
if (!migrate_use_compression()) {
return;
}
- compression_switch = true;
thread_count = migrate_compress_threads();
compress_threads = g_new0(QemuThread, thread_count);
comp_param = g_new0(CompressParam, thread_count);
}
/**
- * save_page_header: Write page header to wire
+ * save_page_header: write page header to wire
*
* If this is the 1st block, it also writes the block identification
*
- * Returns: Number of bytes written
+ * Returns the number of bytes written
*
* @f: QEMUFile where to send the data
* @block: block that contains the page we want to send
* @offset: offset inside the block for the page
* in the lower bits, it contains flags
*/
-static size_t save_page_header(QEMUFile *f, RAMBlock *block, ram_addr_t offset)
+static size_t save_page_header(RAMState *rs, QEMUFile *f, RAMBlock *block,
+ ram_addr_t offset)
{
size_t size, len;
+ if (block == rs->last_sent_block) {
+ offset |= RAM_SAVE_FLAG_CONTINUE;
+ }
qemu_put_be64(f, offset);
size = 8;
qemu_put_byte(f, len);
qemu_put_buffer(f, (uint8_t *)block->idstr, len);
size += 1 + len;
+ rs->last_sent_block = block;
}
return size;
}
-/* Reduce amount of guest cpu execution to hopefully slow down memory writes.
- * If guest dirty memory rate is reduced below the rate at which we can
- * transfer pages to the destination then we should be able to complete
- * migration. Some workloads dirty memory way too fast and will not effectively
- * converge, even with auto-converge.
+/**
+ * mig_throttle_guest_down: throotle down the guest
+ *
+ * Reduce amount of guest cpu execution to hopefully slow down memory
+ * writes. If guest dirty memory rate is reduced below the rate at
+ * which we can transfer pages to the destination then we should be
+ * able to complete migration. Some workloads dirty memory way too
+ * fast and will not effectively converge, even with auto-converge.
*/
static void mig_throttle_guest_down(void)
{
}
}
-/* Update the xbzrle cache to reflect a page that's been sent as all 0.
+/**
+ * xbzrle_cache_zero_page: insert a zero page in the XBZRLE cache
+ *
+ * @rs: current RAM state
+ * @current_addr: address for the zero page
+ *
+ * Update the xbzrle cache to reflect a page that's been sent as all 0.
* The important thing is that a stale (not-yet-0'd) page be replaced
* by the new data.
* As a bonus, if the page wasn't in the cache it gets added so that
- * when a small write is made into the 0'd page it gets XBZRLE sent
+ * when a small write is made into the 0'd page it gets XBZRLE sent.
*/
-static void xbzrle_cache_zero_page(ram_addr_t current_addr)
+static void xbzrle_cache_zero_page(RAMState *rs, ram_addr_t current_addr)
{
- if (ram_bulk_stage || !migrate_use_xbzrle()) {
+ if (rs->ram_bulk_stage || !migrate_use_xbzrle()) {
return;
}
/* We don't care if this fails to allocate a new cache page
* as long as it updated an old one */
cache_insert(XBZRLE.cache, current_addr, ZERO_TARGET_PAGE,
- bitmap_sync_count);
+ rs->bitmap_sync_count);
}
#define ENCODING_FLAG_XBZRLE 0x1
* 0 means that page is identical to the one already sent
* -1 means that xbzrle would be longer than normal
*
- * @f: QEMUFile where to send the data
- * @current_data:
- * @current_addr:
+ * @rs: current RAM state
+ * @current_data: pointer to the address of the page contents
+ * @current_addr: addr of the page
* @block: block that contains the page we want to send
* @offset: offset inside the block for the page
* @last_stage: if we are at the completion stage
- * @bytes_transferred: increase it with the number of transferred bytes
*/
-static int save_xbzrle_page(QEMUFile *f, uint8_t **current_data,
+static int save_xbzrle_page(RAMState *rs, uint8_t **current_data,
ram_addr_t current_addr, RAMBlock *block,
- ram_addr_t offset, bool last_stage,
- uint64_t *bytes_transferred)
+ ram_addr_t offset, bool last_stage)
{
int encoded_len = 0, bytes_xbzrle;
uint8_t *prev_cached_page;
- if (!cache_is_cached(XBZRLE.cache, current_addr, bitmap_sync_count)) {
- acct_info.xbzrle_cache_miss++;
+ if (!cache_is_cached(XBZRLE.cache, current_addr, rs->bitmap_sync_count)) {
+ rs->xbzrle_cache_miss++;
if (!last_stage) {
if (cache_insert(XBZRLE.cache, current_addr, *current_data,
- bitmap_sync_count) == -1) {
+ rs->bitmap_sync_count) == -1) {
return -1;
} else {
/* update *current_data when the page has been
return 0;
} else if (encoded_len == -1) {
trace_save_xbzrle_page_overflow();
- acct_info.xbzrle_overflows++;
+ rs->xbzrle_overflows++;
/* update data in the cache */
if (!last_stage) {
memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE);
}
/* Send XBZRLE based compressed page */
- bytes_xbzrle = save_page_header(f, block, offset | RAM_SAVE_FLAG_XBZRLE);
- qemu_put_byte(f, ENCODING_FLAG_XBZRLE);
- qemu_put_be16(f, encoded_len);
- qemu_put_buffer(f, XBZRLE.encoded_buf, encoded_len);
+ bytes_xbzrle = save_page_header(rs, rs->f, block,
+ offset | RAM_SAVE_FLAG_XBZRLE);
+ qemu_put_byte(rs->f, ENCODING_FLAG_XBZRLE);
+ qemu_put_be16(rs->f, encoded_len);
+ qemu_put_buffer(rs->f, XBZRLE.encoded_buf, encoded_len);
bytes_xbzrle += encoded_len + 1 + 2;
- acct_info.xbzrle_pages++;
- acct_info.xbzrle_bytes += bytes_xbzrle;
- *bytes_transferred += bytes_xbzrle;
+ rs->xbzrle_pages++;
+ rs->xbzrle_bytes += bytes_xbzrle;
+ rs->bytes_transferred += bytes_xbzrle;
return 1;
}
-/* Called with rcu_read_lock() to protect migration_bitmap
- * rb: The RAMBlock to search for dirty pages in
- * start: Start address (typically so we can continue from previous page)
- * ram_addr_abs: Pointer into which to store the address of the dirty page
- * within the global ram_addr space
+/**
+ * migration_bitmap_find_dirty: find the next dirty page from start
*
- * Returns: byte offset within memory region of the start of a dirty page
+ * Called with rcu_read_lock() to protect migration_bitmap
+ *
+ * Returns the byte offset within memory region of the start of a dirty page
+ *
+ * @rs: current RAM state
+ * @rb: RAMBlock where to search for dirty pages
+ * @start: page where we start the search
*/
static inline
-ram_addr_t migration_bitmap_find_dirty(RAMBlock *rb,
- ram_addr_t start,
- ram_addr_t *ram_addr_abs)
+unsigned long migration_bitmap_find_dirty(RAMState *rs, RAMBlock *rb,
+ unsigned long start)
{
- unsigned long base = rb->offset >> TARGET_PAGE_BITS;
- unsigned long nr = base + (start >> TARGET_PAGE_BITS);
- uint64_t rb_size = rb->used_length;
- unsigned long size = base + (rb_size >> TARGET_PAGE_BITS);
- unsigned long *bitmap;
-
+ unsigned long size = rb->used_length >> TARGET_PAGE_BITS;
+ unsigned long *bitmap = rb->bmap;
unsigned long next;
- bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- if (ram_bulk_stage && nr > base) {
- next = nr + 1;
+ if (rs->ram_bulk_stage && start > 0) {
+ next = start + 1;
} else {
- next = find_next_bit(bitmap, size, nr);
+ next = find_next_bit(bitmap, size, start);
}
- *ram_addr_abs = next << TARGET_PAGE_BITS;
- return (next - base) << TARGET_PAGE_BITS;
+ return next;
}
-static inline bool migration_bitmap_clear_dirty(ram_addr_t addr)
+static inline bool migration_bitmap_clear_dirty(RAMState *rs,
+ RAMBlock *rb,
+ unsigned long page)
{
bool ret;
- int nr = addr >> TARGET_PAGE_BITS;
- unsigned long *bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- ret = test_and_clear_bit(nr, bitmap);
+ ret = test_and_clear_bit(page, rb->bmap);
if (ret) {
- migration_dirty_pages--;
+ rs->migration_dirty_pages--;
}
return ret;
}
-static void migration_bitmap_sync_range(ram_addr_t start, ram_addr_t length)
-{
- unsigned long *bitmap;
- bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- migration_dirty_pages +=
- cpu_physical_memory_sync_dirty_bitmap(bitmap, start, length);
-}
-
-/* Fix me: there are too many global variables used in migration process. */
-static int64_t start_time;
-static int64_t bytes_xfer_prev;
-static int64_t num_dirty_pages_period;
-static uint64_t xbzrle_cache_miss_prev;
-static uint64_t iterations_prev;
-
-static void migration_bitmap_sync_init(void)
+static void migration_bitmap_sync_range(RAMState *rs, RAMBlock *rb,
+ ram_addr_t start, ram_addr_t length)
{
- start_time = 0;
- bytes_xfer_prev = 0;
- num_dirty_pages_period = 0;
- xbzrle_cache_miss_prev = 0;
- iterations_prev = 0;
+ rs->migration_dirty_pages +=
+ cpu_physical_memory_sync_dirty_bitmap(rb, start, length,
+ &rs->num_dirty_pages_period);
}
-/* Returns a summary bitmap of the page sizes of all RAMBlocks;
- * for VMs with just normal pages this is equivalent to the
- * host page size. If it's got some huge pages then it's the OR
- * of all the different page sizes.
+/**
+ * ram_pagesize_summary: calculate all the pagesizes of a VM
+ *
+ * Returns a summary bitmap of the page sizes of all RAMBlocks
+ *
+ * For VMs with just normal pages this is equivalent to the host page
+ * size. If it's got some huge pages then it's the OR of all the
+ * different page sizes.
*/
uint64_t ram_pagesize_summary(void)
{
RAMBlock *block;
uint64_t summary = 0;
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ RAMBLOCK_FOREACH(block) {
summary |= block->page_size;
}
return summary;
}
-static void migration_bitmap_sync(void)
+static void migration_bitmap_sync(RAMState *rs)
{
RAMBlock *block;
- uint64_t num_dirty_pages_init = migration_dirty_pages;
- MigrationState *s = migrate_get_current();
int64_t end_time;
- int64_t bytes_xfer_now;
-
- bitmap_sync_count++;
+ uint64_t bytes_xfer_now;
- if (!bytes_xfer_prev) {
- bytes_xfer_prev = ram_bytes_transferred();
- }
+ rs->bitmap_sync_count++;
- if (!start_time) {
- start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
+ if (!rs->time_last_bitmap_sync) {
+ rs->time_last_bitmap_sync = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
}
trace_migration_bitmap_sync_start();
memory_global_dirty_log_sync();
- qemu_mutex_lock(&migration_bitmap_mutex);
+ qemu_mutex_lock(&rs->bitmap_mutex);
rcu_read_lock();
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
- migration_bitmap_sync_range(block->offset, block->used_length);
+ RAMBLOCK_FOREACH(block) {
+ migration_bitmap_sync_range(rs, block, 0, block->used_length);
}
rcu_read_unlock();
- qemu_mutex_unlock(&migration_bitmap_mutex);
+ qemu_mutex_unlock(&rs->bitmap_mutex);
+
+ trace_migration_bitmap_sync_end(rs->num_dirty_pages_period);
- trace_migration_bitmap_sync_end(migration_dirty_pages
- - num_dirty_pages_init);
- num_dirty_pages_period += migration_dirty_pages - num_dirty_pages_init;
end_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME);
/* more than 1 second = 1000 millisecons */
- if (end_time > start_time + 1000) {
+ if (end_time > rs->time_last_bitmap_sync + 1000) {
+ /* calculate period counters */
+ rs->dirty_pages_rate = rs->num_dirty_pages_period * 1000
+ / (end_time - rs->time_last_bitmap_sync);
+ bytes_xfer_now = ram_bytes_transferred();
+
if (migrate_auto_converge()) {
/* The following detection logic can be refined later. For now:
Check to see if the dirtied bytes is 50% more than the approx.
amount of bytes that just got transferred since the last time we
were in this routine. If that happens twice, start or increase
throttling */
- bytes_xfer_now = ram_bytes_transferred();
- if (s->dirty_pages_rate &&
- (num_dirty_pages_period * TARGET_PAGE_SIZE >
- (bytes_xfer_now - bytes_xfer_prev)/2) &&
- (dirty_rate_high_cnt++ >= 2)) {
+ if ((rs->num_dirty_pages_period * TARGET_PAGE_SIZE >
+ (bytes_xfer_now - rs->bytes_xfer_prev) / 2) &&
+ (++rs->dirty_rate_high_cnt >= 2)) {
trace_migration_throttle();
- dirty_rate_high_cnt = 0;
+ rs->dirty_rate_high_cnt = 0;
mig_throttle_guest_down();
- }
- bytes_xfer_prev = bytes_xfer_now;
+ }
}
if (migrate_use_xbzrle()) {
- if (iterations_prev != acct_info.iterations) {
- acct_info.xbzrle_cache_miss_rate =
- (double)(acct_info.xbzrle_cache_miss -
- xbzrle_cache_miss_prev) /
- (acct_info.iterations - iterations_prev);
+ if (rs->iterations_prev != rs->iterations) {
+ rs->xbzrle_cache_miss_rate =
+ (double)(rs->xbzrle_cache_miss -
+ rs->xbzrle_cache_miss_prev) /
+ (rs->iterations - rs->iterations_prev);
}
- iterations_prev = acct_info.iterations;
- xbzrle_cache_miss_prev = acct_info.xbzrle_cache_miss;
+ rs->iterations_prev = rs->iterations;
+ rs->xbzrle_cache_miss_prev = rs->xbzrle_cache_miss;
}
- s->dirty_pages_rate = num_dirty_pages_period * 1000
- / (end_time - start_time);
- s->dirty_bytes_rate = s->dirty_pages_rate * TARGET_PAGE_SIZE;
- start_time = end_time;
- num_dirty_pages_period = 0;
+
+ /* reset period counters */
+ rs->time_last_bitmap_sync = end_time;
+ rs->num_dirty_pages_period = 0;
+ rs->bytes_xfer_prev = bytes_xfer_now;
}
- s->dirty_sync_count = bitmap_sync_count;
if (migrate_use_events()) {
- qapi_event_send_migration_pass(bitmap_sync_count, NULL);
+ qapi_event_send_migration_pass(rs->bitmap_sync_count, NULL);
}
}
/**
- * save_zero_page: Send the zero page to the stream
+ * save_zero_page: send the zero page to the stream
*
- * Returns: Number of pages written.
+ * Returns the number of pages written.
*
- * @f: QEMUFile where to send the data
+ * @rs: current RAM state
* @block: block that contains the page we want to send
* @offset: offset inside the block for the page
* @p: pointer to the page
- * @bytes_transferred: increase it with the number of transferred bytes
*/
-static int save_zero_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset,
- uint8_t *p, uint64_t *bytes_transferred)
+static int save_zero_page(RAMState *rs, RAMBlock *block, ram_addr_t offset,
+ uint8_t *p)
{
int pages = -1;
if (is_zero_range(p, TARGET_PAGE_SIZE)) {
- acct_info.dup_pages++;
- *bytes_transferred += save_page_header(f, block,
- offset | RAM_SAVE_FLAG_COMPRESS);
- qemu_put_byte(f, 0);
- *bytes_transferred += 1;
+ rs->zero_pages++;
+ rs->bytes_transferred +=
+ save_page_header(rs, rs->f, block, offset | RAM_SAVE_FLAG_ZERO);
+ qemu_put_byte(rs->f, 0);
+ rs->bytes_transferred += 1;
pages = 1;
}
return pages;
}
-static void ram_release_pages(MigrationState *ms, const char *block_name,
- uint64_t offset, int pages)
+static void ram_release_pages(const char *rbname, uint64_t offset, int pages)
{
- if (!migrate_release_ram() || !migration_in_postcopy(ms)) {
+ if (!migrate_release_ram() || !migration_in_postcopy()) {
return;
}
- ram_discard_range(NULL, block_name, offset, pages << TARGET_PAGE_BITS);
+ ram_discard_range(rbname, offset, pages << TARGET_PAGE_BITS);
}
/**
- * ram_save_page: Send the given page to the stream
+ * ram_save_page: send the given page to the stream
*
- * Returns: Number of pages written.
+ * Returns the number of pages written.
* < 0 - error
* >=0 - Number of pages written - this might legally be 0
* if xbzrle noticed the page was the same.
*
- * @ms: The current migration state.
- * @f: QEMUFile where to send the data
+ * @rs: current RAM state
* @block: block that contains the page we want to send
* @offset: offset inside the block for the page
* @last_stage: if we are at the completion stage
- * @bytes_transferred: increase it with the number of transferred bytes
*/
-static int ram_save_page(MigrationState *ms, QEMUFile *f, PageSearchStatus *pss,
- bool last_stage, uint64_t *bytes_transferred)
+static int ram_save_page(RAMState *rs, PageSearchStatus *pss, bool last_stage)
{
int pages = -1;
uint64_t bytes_xmit;
int ret;
bool send_async = true;
RAMBlock *block = pss->block;
- ram_addr_t offset = pss->offset;
+ ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
p = block->host + offset;
+ trace_ram_save_page(block->idstr, (uint64_t)offset, p);
/* In doubt sent page as normal */
bytes_xmit = 0;
- ret = ram_control_save_page(f, block->offset,
+ ret = ram_control_save_page(rs->f, block->offset,
offset, TARGET_PAGE_SIZE, &bytes_xmit);
if (bytes_xmit) {
- *bytes_transferred += bytes_xmit;
+ rs->bytes_transferred += bytes_xmit;
pages = 1;
}
current_addr = block->offset + offset;
- if (block == last_sent_block) {
- offset |= RAM_SAVE_FLAG_CONTINUE;
- }
if (ret != RAM_SAVE_CONTROL_NOT_SUPP) {
if (ret != RAM_SAVE_CONTROL_DELAYED) {
if (bytes_xmit > 0) {
- acct_info.norm_pages++;
+ rs->norm_pages++;
} else if (bytes_xmit == 0) {
- acct_info.dup_pages++;
+ rs->zero_pages++;
}
}
} else {
- pages = save_zero_page(f, block, offset, p, bytes_transferred);
+ pages = save_zero_page(rs, block, offset, p);
if (pages > 0) {
/* Must let xbzrle know, otherwise a previous (now 0'd) cached
* page would be stale
*/
- xbzrle_cache_zero_page(current_addr);
- ram_release_pages(ms, block->idstr, pss->offset, pages);
- } else if (!ram_bulk_stage &&
- !migration_in_postcopy(ms) && migrate_use_xbzrle()) {
- pages = save_xbzrle_page(f, &p, current_addr, block,
- offset, last_stage, bytes_transferred);
+ xbzrle_cache_zero_page(rs, current_addr);
+ ram_release_pages(block->idstr, offset, pages);
+ } else if (!rs->ram_bulk_stage &&
+ !migration_in_postcopy() && migrate_use_xbzrle()) {
+ pages = save_xbzrle_page(rs, &p, current_addr, block,
+ offset, last_stage);
if (!last_stage) {
/* Can't send this cached data async, since the cache page
* might get updated before it gets to the wire
/* XBZRLE overflow or normal page */
if (pages == -1) {
- *bytes_transferred += save_page_header(f, block,
- offset | RAM_SAVE_FLAG_PAGE);
+ rs->bytes_transferred += save_page_header(rs, rs->f, block,
+ offset | RAM_SAVE_FLAG_PAGE);
if (send_async) {
- qemu_put_buffer_async(f, p, TARGET_PAGE_SIZE,
+ qemu_put_buffer_async(rs->f, p, TARGET_PAGE_SIZE,
migrate_release_ram() &
- migration_in_postcopy(ms));
+ migration_in_postcopy());
} else {
- qemu_put_buffer(f, p, TARGET_PAGE_SIZE);
+ qemu_put_buffer(rs->f, p, TARGET_PAGE_SIZE);
}
- *bytes_transferred += TARGET_PAGE_SIZE;
+ rs->bytes_transferred += TARGET_PAGE_SIZE;
pages = 1;
- acct_info.norm_pages++;
+ rs->norm_pages++;
}
XBZRLE_cache_unlock();
static int do_compress_ram_page(QEMUFile *f, RAMBlock *block,
ram_addr_t offset)
{
+ RAMState *rs = &ram_state;
int bytes_sent, blen;
uint8_t *p = block->host + (offset & TARGET_PAGE_MASK);
- bytes_sent = save_page_header(f, block, offset |
+ bytes_sent = save_page_header(rs, f, block, offset |
RAM_SAVE_FLAG_COMPRESS_PAGE);
blen = qemu_put_compression_data(f, p, TARGET_PAGE_SIZE,
migrate_compress_level());
error_report("compressed data failed!");
} else {
bytes_sent += blen;
- ram_release_pages(migrate_get_current(), block->idstr,
- offset & TARGET_PAGE_MASK, 1);
+ ram_release_pages(block->idstr, offset & TARGET_PAGE_MASK, 1);
}
return bytes_sent;
}
-static uint64_t bytes_transferred;
-
-static void flush_compressed_data(QEMUFile *f)
+static void flush_compressed_data(RAMState *rs)
{
int idx, len, thread_count;
for (idx = 0; idx < thread_count; idx++) {
qemu_mutex_lock(&comp_param[idx].mutex);
if (!comp_param[idx].quit) {
- len = qemu_put_qemu_file(f, comp_param[idx].file);
- bytes_transferred += len;
+ len = qemu_put_qemu_file(rs->f, comp_param[idx].file);
+ rs->bytes_transferred += len;
}
qemu_mutex_unlock(&comp_param[idx].mutex);
}
param->offset = offset;
}
-static int compress_page_with_multi_thread(QEMUFile *f, RAMBlock *block,
- ram_addr_t offset,
- uint64_t *bytes_transferred)
+static int compress_page_with_multi_thread(RAMState *rs, RAMBlock *block,
+ ram_addr_t offset)
{
int idx, thread_count, bytes_xmit = -1, pages = -1;
for (idx = 0; idx < thread_count; idx++) {
if (comp_param[idx].done) {
comp_param[idx].done = false;
- bytes_xmit = qemu_put_qemu_file(f, comp_param[idx].file);
+ bytes_xmit = qemu_put_qemu_file(rs->f, comp_param[idx].file);
qemu_mutex_lock(&comp_param[idx].mutex);
set_compress_params(&comp_param[idx], block, offset);
qemu_cond_signal(&comp_param[idx].cond);
qemu_mutex_unlock(&comp_param[idx].mutex);
pages = 1;
- acct_info.norm_pages++;
- *bytes_transferred += bytes_xmit;
+ rs->norm_pages++;
+ rs->bytes_transferred += bytes_xmit;
break;
}
}
/**
* ram_save_compressed_page: compress the given page and send it to the stream
*
- * Returns: Number of pages written.
+ * Returns the number of pages written.
*
- * @ms: The current migration state.
- * @f: QEMUFile where to send the data
+ * @rs: current RAM state
* @block: block that contains the page we want to send
* @offset: offset inside the block for the page
* @last_stage: if we are at the completion stage
- * @bytes_transferred: increase it with the number of transferred bytes
*/
-static int ram_save_compressed_page(MigrationState *ms, QEMUFile *f,
- PageSearchStatus *pss, bool last_stage,
- uint64_t *bytes_transferred)
+static int ram_save_compressed_page(RAMState *rs, PageSearchStatus *pss,
+ bool last_stage)
{
int pages = -1;
uint64_t bytes_xmit = 0;
uint8_t *p;
int ret, blen;
RAMBlock *block = pss->block;
- ram_addr_t offset = pss->offset;
+ ram_addr_t offset = pss->page << TARGET_PAGE_BITS;
p = block->host + offset;
- ret = ram_control_save_page(f, block->offset,
+ ret = ram_control_save_page(rs->f, block->offset,
offset, TARGET_PAGE_SIZE, &bytes_xmit);
if (bytes_xmit) {
- *bytes_transferred += bytes_xmit;
+ rs->bytes_transferred += bytes_xmit;
pages = 1;
}
if (ret != RAM_SAVE_CONTROL_NOT_SUPP) {
if (ret != RAM_SAVE_CONTROL_DELAYED) {
if (bytes_xmit > 0) {
- acct_info.norm_pages++;
+ rs->norm_pages++;
} else if (bytes_xmit == 0) {
- acct_info.dup_pages++;
+ rs->zero_pages++;
}
}
} else {
* out, keeping this order is important, because the 'cont' flag
* is used to avoid resending the block name.
*/
- if (block != last_sent_block) {
- flush_compressed_data(f);
- pages = save_zero_page(f, block, offset, p, bytes_transferred);
+ if (block != rs->last_sent_block) {
+ flush_compressed_data(rs);
+ pages = save_zero_page(rs, block, offset, p);
if (pages == -1) {
/* Make sure the first page is sent out before other pages */
- bytes_xmit = save_page_header(f, block, offset |
+ bytes_xmit = save_page_header(rs, rs->f, block, offset |
RAM_SAVE_FLAG_COMPRESS_PAGE);
- blen = qemu_put_compression_data(f, p, TARGET_PAGE_SIZE,
+ blen = qemu_put_compression_data(rs->f, p, TARGET_PAGE_SIZE,
migrate_compress_level());
if (blen > 0) {
- *bytes_transferred += bytes_xmit + blen;
- acct_info.norm_pages++;
+ rs->bytes_transferred += bytes_xmit + blen;
+ rs->norm_pages++;
pages = 1;
} else {
- qemu_file_set_error(f, blen);
+ qemu_file_set_error(rs->f, blen);
error_report("compressed data failed!");
}
}
if (pages > 0) {
- ram_release_pages(ms, block->idstr, pss->offset, pages);
+ ram_release_pages(block->idstr, offset, pages);
}
} else {
- offset |= RAM_SAVE_FLAG_CONTINUE;
- pages = save_zero_page(f, block, offset, p, bytes_transferred);
+ pages = save_zero_page(rs, block, offset, p);
if (pages == -1) {
- pages = compress_page_with_multi_thread(f, block, offset,
- bytes_transferred);
+ pages = compress_page_with_multi_thread(rs, block, offset);
} else {
- ram_release_pages(ms, block->idstr, pss->offset, pages);
+ ram_release_pages(block->idstr, offset, pages);
}
}
}
return pages;
}
-/*
- * Find the next dirty page and update any state associated with
- * the search process.
+/**
+ * find_dirty_block: find the next dirty page and update any state
+ * associated with the search process.
*
- * Returns: True if a page is found
+ * Returns if a page is found
*
- * @f: Current migration stream.
- * @pss: Data about the state of the current dirty page scan.
- * @*again: Set to false if the search has scanned the whole of RAM
- * *ram_addr_abs: Pointer into which to store the address of the dirty page
- * within the global ram_addr space
+ * @rs: current RAM state
+ * @pss: data about the state of the current dirty page scan
+ * @again: set to false if the search has scanned the whole of RAM
*/
-static bool find_dirty_block(QEMUFile *f, PageSearchStatus *pss,
- bool *again, ram_addr_t *ram_addr_abs)
+static bool find_dirty_block(RAMState *rs, PageSearchStatus *pss, bool *again)
{
- pss->offset = migration_bitmap_find_dirty(pss->block, pss->offset,
- ram_addr_abs);
- if (pss->complete_round && pss->block == last_seen_block &&
- pss->offset >= last_offset) {
+ pss->page = migration_bitmap_find_dirty(rs, pss->block, pss->page);
+ if (pss->complete_round && pss->block == rs->last_seen_block &&
+ pss->page >= rs->last_page) {
/*
* We've been once around the RAM and haven't found anything.
* Give up.
*again = false;
return false;
}
- if (pss->offset >= pss->block->used_length) {
+ if ((pss->page << TARGET_PAGE_BITS) >= pss->block->used_length) {
/* Didn't find anything in this RAM Block */
- pss->offset = 0;
+ pss->page = 0;
pss->block = QLIST_NEXT_RCU(pss->block, next);
if (!pss->block) {
/* Hit the end of the list */
pss->block = QLIST_FIRST_RCU(&ram_list.blocks);
/* Flag that we've looped */
pss->complete_round = true;
- ram_bulk_stage = false;
+ rs->ram_bulk_stage = false;
if (migrate_use_xbzrle()) {
/* If xbzrle is on, stop using the data compression at this
* point. In theory, xbzrle can do better than compression.
*/
- flush_compressed_data(f);
- compression_switch = false;
+ flush_compressed_data(rs);
}
}
/* Didn't find anything this time, but try again on the new block */
}
}
-/*
+/**
+ * unqueue_page: gets a page of the queue
+ *
* Helper for 'get_queued_page' - gets a page off the queue
- * ms: MigrationState in
- * *offset: Used to return the offset within the RAMBlock
- * ram_addr_abs: global offset in the dirty/sent bitmaps
*
- * Returns: block (or NULL if none available)
+ * Returns the block of the page (or NULL if none available)
+ *
+ * @rs: current RAM state
+ * @offset: used to return the offset within the RAMBlock
*/
-static RAMBlock *unqueue_page(MigrationState *ms, ram_addr_t *offset,
- ram_addr_t *ram_addr_abs)
+static RAMBlock *unqueue_page(RAMState *rs, ram_addr_t *offset)
{
RAMBlock *block = NULL;
- qemu_mutex_lock(&ms->src_page_req_mutex);
- if (!QSIMPLEQ_EMPTY(&ms->src_page_requests)) {
- struct MigrationSrcPageRequest *entry =
- QSIMPLEQ_FIRST(&ms->src_page_requests);
+ qemu_mutex_lock(&rs->src_page_req_mutex);
+ if (!QSIMPLEQ_EMPTY(&rs->src_page_requests)) {
+ struct RAMSrcPageRequest *entry =
+ QSIMPLEQ_FIRST(&rs->src_page_requests);
block = entry->rb;
*offset = entry->offset;
- *ram_addr_abs = (entry->offset + entry->rb->offset) &
- TARGET_PAGE_MASK;
if (entry->len > TARGET_PAGE_SIZE) {
entry->len -= TARGET_PAGE_SIZE;
entry->offset += TARGET_PAGE_SIZE;
} else {
memory_region_unref(block->mr);
- QSIMPLEQ_REMOVE_HEAD(&ms->src_page_requests, next_req);
+ QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req);
g_free(entry);
}
}
- qemu_mutex_unlock(&ms->src_page_req_mutex);
+ qemu_mutex_unlock(&rs->src_page_req_mutex);
return block;
}
-/*
- * Unqueue a page from the queue fed by postcopy page requests; skips pages
- * that are already sent (!dirty)
+/**
+ * get_queued_page: unqueue a page from the postocpy requests
*
- * ms: MigrationState in
- * pss: PageSearchStatus structure updated with found block/offset
- * ram_addr_abs: global offset in the dirty/sent bitmaps
+ * Skips pages that are already sent (!dirty)
*
- * Returns: true if a queued page is found
+ * Returns if a queued page is found
+ *
+ * @rs: current RAM state
+ * @pss: data about the state of the current dirty page scan
*/
-static bool get_queued_page(MigrationState *ms, PageSearchStatus *pss,
- ram_addr_t *ram_addr_abs)
+static bool get_queued_page(RAMState *rs, PageSearchStatus *pss)
{
RAMBlock *block;
ram_addr_t offset;
bool dirty;
do {
- block = unqueue_page(ms, &offset, ram_addr_abs);
+ block = unqueue_page(rs, &offset);
/*
* We're sending this page, and since it's postcopy nothing else
* will dirty it, and we must make sure it doesn't get sent again
* search already sent it.
*/
if (block) {
- unsigned long *bitmap;
- bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- dirty = test_bit(*ram_addr_abs >> TARGET_PAGE_BITS, bitmap);
+ unsigned long page;
+
+ page = offset >> TARGET_PAGE_BITS;
+ dirty = test_bit(page, block->bmap);
if (!dirty) {
- trace_get_queued_page_not_dirty(
- block->idstr, (uint64_t)offset,
- (uint64_t)*ram_addr_abs,
- test_bit(*ram_addr_abs >> TARGET_PAGE_BITS,
- atomic_rcu_read(&migration_bitmap_rcu)->unsentmap));
+ trace_get_queued_page_not_dirty(block->idstr, (uint64_t)offset,
+ page, test_bit(page, block->unsentmap));
} else {
- trace_get_queued_page(block->idstr,
- (uint64_t)offset,
- (uint64_t)*ram_addr_abs);
+ trace_get_queued_page(block->idstr, (uint64_t)offset, page);
}
}
* in (migration_bitmap_find_and_reset_dirty) that every page is
* dirty, that's no longer true.
*/
- ram_bulk_stage = false;
+ rs->ram_bulk_stage = false;
/*
* We want the background search to continue from the queued page
* it just requested.
*/
pss->block = block;
- pss->offset = offset;
+ pss->page = offset >> TARGET_PAGE_BITS;
}
return !!block;
}
/**
- * flush_page_queue: Flush any remaining pages in the ram request queue
- * it should be empty at the end anyway, but in error cases there may be
- * some left.
+ * migration_page_queue_free: drop any remaining pages in the ram
+ * request queue
+ *
+ * It should be empty at the end anyway, but in error cases there may
+ * be some left. in case that there is any page left, we drop it.
*
- * ms: MigrationState
*/
-void flush_page_queue(MigrationState *ms)
+void migration_page_queue_free(void)
{
- struct MigrationSrcPageRequest *mspr, *next_mspr;
+ struct RAMSrcPageRequest *mspr, *next_mspr;
+ RAMState *rs = &ram_state;
/* This queue generally should be empty - but in the case of a failed
* migration might have some droppings in.
*/
rcu_read_lock();
- QSIMPLEQ_FOREACH_SAFE(mspr, &ms->src_page_requests, next_req, next_mspr) {
+ QSIMPLEQ_FOREACH_SAFE(mspr, &rs->src_page_requests, next_req, next_mspr) {
memory_region_unref(mspr->rb->mr);
- QSIMPLEQ_REMOVE_HEAD(&ms->src_page_requests, next_req);
+ QSIMPLEQ_REMOVE_HEAD(&rs->src_page_requests, next_req);
g_free(mspr);
}
rcu_read_unlock();
}
/**
- * Queue the pages for transmission, e.g. a request from postcopy destination
- * ms: MigrationStatus in which the queue is held
- * rbname: The RAMBlock the request is for - may be NULL (to mean reuse last)
- * start: Offset from the start of the RAMBlock
- * len: Length (in bytes) to send
- * Return: 0 on success
+ * ram_save_queue_pages: queue the page for transmission
+ *
+ * A request from postcopy destination for example.
+ *
+ * Returns zero on success or negative on error
+ *
+ * @rbname: Name of the RAMBLock of the request. NULL means the
+ * same that last one.
+ * @start: starting address from the start of the RAMBlock
+ * @len: length (in bytes) to send
*/
-int ram_save_queue_pages(MigrationState *ms, const char *rbname,
- ram_addr_t start, ram_addr_t len)
+int ram_save_queue_pages(const char *rbname, ram_addr_t start, ram_addr_t len)
{
RAMBlock *ramblock;
+ RAMState *rs = &ram_state;
- ms->postcopy_requests++;
+ rs->postcopy_requests++;
rcu_read_lock();
if (!rbname) {
/* Reuse last RAMBlock */
- ramblock = ms->last_req_rb;
+ ramblock = rs->last_req_rb;
if (!ramblock) {
/*
error_report("ram_save_queue_pages no block '%s'", rbname);
goto err;
}
- ms->last_req_rb = ramblock;
+ rs->last_req_rb = ramblock;
}
trace_ram_save_queue_pages(ramblock->idstr, start, len);
if (start+len > ramblock->used_length) {
goto err;
}
- struct MigrationSrcPageRequest *new_entry =
- g_malloc0(sizeof(struct MigrationSrcPageRequest));
+ struct RAMSrcPageRequest *new_entry =
+ g_malloc0(sizeof(struct RAMSrcPageRequest));
new_entry->rb = ramblock;
new_entry->offset = start;
new_entry->len = len;
memory_region_ref(ramblock->mr);
- qemu_mutex_lock(&ms->src_page_req_mutex);
- QSIMPLEQ_INSERT_TAIL(&ms->src_page_requests, new_entry, next_req);
- qemu_mutex_unlock(&ms->src_page_req_mutex);
+ qemu_mutex_lock(&rs->src_page_req_mutex);
+ QSIMPLEQ_INSERT_TAIL(&rs->src_page_requests, new_entry, next_req);
+ qemu_mutex_unlock(&rs->src_page_req_mutex);
rcu_read_unlock();
return 0;
}
/**
- * ram_save_target_page: Save one target page
+ * ram_save_target_page: save one target page
*
+ * Returns the number of pages written
*
- * @f: QEMUFile where to send the data
- * @block: pointer to block that contains the page we want to send
- * @offset: offset inside the block for the page;
+ * @rs: current RAM state
+ * @ms: current migration state
+ * @pss: data about the page we want to send
* @last_stage: if we are at the completion stage
- * @bytes_transferred: increase it with the number of transferred bytes
- * @dirty_ram_abs: Address of the start of the dirty page in ram_addr_t space
- *
- * Returns: Number of pages written.
*/
-static int ram_save_target_page(MigrationState *ms, QEMUFile *f,
- PageSearchStatus *pss,
- bool last_stage,
- uint64_t *bytes_transferred,
- ram_addr_t dirty_ram_abs)
+static int ram_save_target_page(RAMState *rs, PageSearchStatus *pss,
+ bool last_stage)
{
int res = 0;
/* Check the pages is dirty and if it is send it */
- if (migration_bitmap_clear_dirty(dirty_ram_abs)) {
- unsigned long *unsentmap;
- if (compression_switch && migrate_use_compression()) {
- res = ram_save_compressed_page(ms, f, pss,
- last_stage,
- bytes_transferred);
+ if (migration_bitmap_clear_dirty(rs, pss->block, pss->page)) {
+ /*
+ * If xbzrle is on, stop using the data compression after first
+ * round of migration even if compression is enabled. In theory,
+ * xbzrle can do better than compression.
+ */
+ if (migrate_use_compression() &&
+ (rs->ram_bulk_stage || !migrate_use_xbzrle())) {
+ res = ram_save_compressed_page(rs, pss, last_stage);
} else {
- res = ram_save_page(ms, f, pss, last_stage,
- bytes_transferred);
+ res = ram_save_page(rs, pss, last_stage);
}
if (res < 0) {
return res;
}
- unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap;
- if (unsentmap) {
- clear_bit(dirty_ram_abs >> TARGET_PAGE_BITS, unsentmap);
- }
- /* Only update last_sent_block if a block was actually sent; xbzrle
- * might have decided the page was identical so didn't bother writing
- * to the stream.
- */
- if (res > 0) {
- last_sent_block = pss->block;
+ if (pss->block->unsentmap) {
+ clear_bit(pss->page, pss->block->unsentmap);
}
}
}
/**
- * ram_save_host_page: Starting at *offset send pages up to the end
- * of the current host page. It's valid for the initial
- * offset to point into the middle of a host page
- * in which case the remainder of the hostpage is sent.
- * Only dirty target pages are sent.
- * Note that the host page size may be a huge page for this
- * block.
+ * ram_save_host_page: save a whole host page
*
- * Returns: Number of pages written.
+ * Starting at *offset send pages up to the end of the current host
+ * page. It's valid for the initial offset to point into the middle of
+ * a host page in which case the remainder of the hostpage is sent.
+ * Only dirty target pages are sent. Note that the host page size may
+ * be a huge page for this block.
+ * The saving stops at the boundary of the used_length of the block
+ * if the RAMBlock isn't a multiple of the host page size.
*
- * @f: QEMUFile where to send the data
- * @block: pointer to block that contains the page we want to send
- * @offset: offset inside the block for the page; updated to last target page
- * sent
+ * Returns the number of pages written or negative on error
+ *
+ * @rs: current RAM state
+ * @ms: current migration state
+ * @pss: data about the page we want to send
* @last_stage: if we are at the completion stage
- * @bytes_transferred: increase it with the number of transferred bytes
- * @dirty_ram_abs: Address of the start of the dirty page in ram_addr_t space
*/
-static int ram_save_host_page(MigrationState *ms, QEMUFile *f,
- PageSearchStatus *pss,
- bool last_stage,
- uint64_t *bytes_transferred,
- ram_addr_t dirty_ram_abs)
+static int ram_save_host_page(RAMState *rs, PageSearchStatus *pss,
+ bool last_stage)
{
int tmppages, pages = 0;
- size_t pagesize = qemu_ram_pagesize(pss->block);
+ size_t pagesize_bits =
+ qemu_ram_pagesize(pss->block) >> TARGET_PAGE_BITS;
do {
- tmppages = ram_save_target_page(ms, f, pss, last_stage,
- bytes_transferred, dirty_ram_abs);
+ tmppages = ram_save_target_page(rs, pss, last_stage);
if (tmppages < 0) {
return tmppages;
}
pages += tmppages;
- pss->offset += TARGET_PAGE_SIZE;
- dirty_ram_abs += TARGET_PAGE_SIZE;
- } while (pss->offset & (pagesize - 1));
+ pss->page++;
+ } while ((pss->page & (pagesize_bits - 1)) &&
+ offset_in_ramblock(pss->block, pss->page << TARGET_PAGE_BITS));
/* The offset we leave with is the last one we looked at */
- pss->offset -= TARGET_PAGE_SIZE;
+ pss->page--;
return pages;
}
/**
- * ram_find_and_save_block: Finds a dirty page and sends it to f
+ * ram_find_and_save_block: finds a dirty page and sends it to f
*
* Called within an RCU critical section.
*
- * Returns: The number of pages written
- * 0 means no dirty pages
+ * Returns the number of pages written where zero means no dirty pages
*
- * @f: QEMUFile where to send the data
+ * @rs: current RAM state
* @last_stage: if we are at the completion stage
- * @bytes_transferred: increase it with the number of transferred bytes
*
* On systems where host-page-size > target-page-size it will send all the
* pages in a host page that are dirty.
*/
-static int ram_find_and_save_block(QEMUFile *f, bool last_stage,
- uint64_t *bytes_transferred)
+static int ram_find_and_save_block(RAMState *rs, bool last_stage)
{
PageSearchStatus pss;
- MigrationState *ms = migrate_get_current();
int pages = 0;
bool again, found;
- ram_addr_t dirty_ram_abs; /* Address of the start of the dirty page in
- ram_addr_t space */
/* No dirty page as there is zero RAM */
if (!ram_bytes_total()) {
return pages;
}
- pss.block = last_seen_block;
- pss.offset = last_offset;
+ pss.block = rs->last_seen_block;
+ pss.page = rs->last_page;
pss.complete_round = false;
if (!pss.block) {
do {
again = true;
- found = get_queued_page(ms, &pss, &dirty_ram_abs);
+ found = get_queued_page(rs, &pss);
if (!found) {
/* priority queue empty, so just search for something dirty */
- found = find_dirty_block(f, &pss, &again, &dirty_ram_abs);
+ found = find_dirty_block(rs, &pss, &again);
}
if (found) {
- pages = ram_save_host_page(ms, f, &pss,
- last_stage, bytes_transferred,
- dirty_ram_abs);
+ pages = ram_save_host_page(rs, &pss, last_stage);
}
} while (!pages && again);
- last_seen_block = pss.block;
- last_offset = pss.offset;
+ rs->last_seen_block = pss.block;
+ rs->last_page = pss.page;
return pages;
}
void acct_update_position(QEMUFile *f, size_t size, bool zero)
{
uint64_t pages = size / TARGET_PAGE_SIZE;
+ RAMState *rs = &ram_state;
+
if (zero) {
- acct_info.dup_pages += pages;
+ rs->zero_pages += pages;
} else {
- acct_info.norm_pages += pages;
- bytes_transferred += size;
+ rs->norm_pages += pages;
+ rs->bytes_transferred += size;
qemu_update_position(f, size);
}
}
-static ram_addr_t ram_save_remaining(void)
-{
- return migration_dirty_pages;
-}
-
-uint64_t ram_bytes_remaining(void)
-{
- return ram_save_remaining() * TARGET_PAGE_SIZE;
-}
-
-uint64_t ram_bytes_transferred(void)
-{
- return bytes_transferred;
-}
-
uint64_t ram_bytes_total(void)
{
RAMBlock *block;
uint64_t total = 0;
rcu_read_lock();
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next)
+ RAMBLOCK_FOREACH(block) {
total += block->used_length;
+ }
rcu_read_unlock();
return total;
}
xbzrle_decoded_buf = NULL;
}
-static void migration_bitmap_free(struct BitmapRcu *bmap)
-{
- g_free(bmap->bmap);
- g_free(bmap->unsentmap);
- g_free(bmap);
-}
-
static void ram_migration_cleanup(void *opaque)
{
+ RAMBlock *block;
+
/* caller have hold iothread lock or is in a bh, so there is
* no writing race against this migration_bitmap
*/
- struct BitmapRcu *bitmap = migration_bitmap_rcu;
- atomic_rcu_set(&migration_bitmap_rcu, NULL);
- if (bitmap) {
- memory_global_dirty_log_stop();
- call_rcu(bitmap, migration_bitmap_free, rcu);
+ memory_global_dirty_log_stop();
+
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ g_free(block->bmap);
+ block->bmap = NULL;
+ g_free(block->unsentmap);
+ block->unsentmap = NULL;
}
XBZRLE_cache_lock();
XBZRLE_cache_unlock();
}
-static void reset_ram_globals(void)
+static void ram_state_reset(RAMState *rs)
{
- last_seen_block = NULL;
- last_sent_block = NULL;
- last_offset = 0;
- last_version = ram_list.version;
- ram_bulk_stage = true;
+ rs->last_seen_block = NULL;
+ rs->last_sent_block = NULL;
+ rs->last_page = 0;
+ rs->last_version = ram_list.version;
+ rs->ram_bulk_stage = true;
}
#define MAX_WAIT 50 /* ms, half buffered_file limit */
-void migration_bitmap_extend(ram_addr_t old, ram_addr_t new)
-{
- /* called in qemu main thread, so there is
- * no writing race against this migration_bitmap
- */
- if (migration_bitmap_rcu) {
- struct BitmapRcu *old_bitmap = migration_bitmap_rcu, *bitmap;
- bitmap = g_new(struct BitmapRcu, 1);
- bitmap->bmap = bitmap_new(new);
-
- /* prevent migration_bitmap content from being set bit
- * by migration_bitmap_sync_range() at the same time.
- * it is safe to migration if migration_bitmap is cleared bit
- * at the same time.
- */
- qemu_mutex_lock(&migration_bitmap_mutex);
- bitmap_copy(bitmap->bmap, old_bitmap->bmap, old);
- bitmap_set(bitmap->bmap, old, new - old);
-
- /* We don't have a way to safely extend the sentmap
- * with RCU; so mark it as missing, entry to postcopy
- * will fail.
- */
- bitmap->unsentmap = NULL;
-
- atomic_rcu_set(&migration_bitmap_rcu, bitmap);
- qemu_mutex_unlock(&migration_bitmap_mutex);
- migration_dirty_pages += new - old;
- call_rcu(old_bitmap, migration_bitmap_free, rcu);
- }
-}
-
/*
* 'expected' is the value you expect the bitmap mostly to be full
* of; it won't bother printing lines that are all this value.
* If 'todump' is null the migration bitmap is dumped.
*/
-void ram_debug_dump_bitmap(unsigned long *todump, bool expected)
+void ram_debug_dump_bitmap(unsigned long *todump, bool expected,
+ unsigned long pages)
{
- int64_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS;
-
int64_t cur;
int64_t linelen = 128;
char linebuf[129];
- if (!todump) {
- todump = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- }
-
- for (cur = 0; cur < ram_pages; cur += linelen) {
+ for (cur = 0; cur < pages; cur += linelen) {
int64_t curb;
bool found = false;
/*
* Last line; catch the case where the line length
* is longer than remaining ram
*/
- if (cur + linelen > ram_pages) {
- linelen = ram_pages - cur;
+ if (cur + linelen > pages) {
+ linelen = pages - cur;
}
for (curb = 0; curb < linelen; curb++) {
bool thisbit = test_bit(cur + curb, todump);
void ram_postcopy_migrated_memory_release(MigrationState *ms)
{
struct RAMBlock *block;
- unsigned long *bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
- unsigned long first = block->offset >> TARGET_PAGE_BITS;
- unsigned long range = first + (block->used_length >> TARGET_PAGE_BITS);
- unsigned long run_start = find_next_zero_bit(bitmap, range, first);
+ RAMBLOCK_FOREACH(block) {
+ unsigned long *bitmap = block->bmap;
+ unsigned long range = block->used_length >> TARGET_PAGE_BITS;
+ unsigned long run_start = find_next_zero_bit(bitmap, range, 0);
while (run_start < range) {
unsigned long run_end = find_next_bit(bitmap, range, run_start + 1);
- ram_discard_range(NULL, block->idstr, run_start << TARGET_PAGE_BITS,
+ ram_discard_range(block->idstr, run_start << TARGET_PAGE_BITS,
(run_end - run_start) << TARGET_PAGE_BITS);
run_start = find_next_zero_bit(bitmap, range, run_end + 1);
}
}
}
-/*
+/**
+ * postcopy_send_discard_bm_ram: discard a RAMBlock
+ *
+ * Returns zero on success
+ *
* Callback from postcopy_each_ram_send_discard for each RAMBlock
* Note: At this point the 'unsentmap' is the processed bitmap combined
* with the dirtymap; so a '1' means it's either dirty or unsent.
- * start,length: Indexes into the bitmap for the first bit
- * representing the named block and length in target-pages
+ *
+ * @ms: current migration state
+ * @pds: state for postcopy
+ * @start: RAMBlock starting page
+ * @length: RAMBlock size
*/
static int postcopy_send_discard_bm_ram(MigrationState *ms,
PostcopyDiscardState *pds,
- unsigned long start,
- unsigned long length)
+ RAMBlock *block)
{
- unsigned long end = start + length; /* one after the end */
+ unsigned long end = block->used_length >> TARGET_PAGE_BITS;
unsigned long current;
- unsigned long *unsentmap;
+ unsigned long *unsentmap = block->unsentmap;
- unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap;
- for (current = start; current < end; ) {
+ for (current = 0; current < end; ) {
unsigned long one = find_next_bit(unsentmap, end, current);
if (one <= end) {
return 0;
}
-/*
+/**
+ * postcopy_each_ram_send_discard: discard all RAMBlocks
+ *
+ * Returns 0 for success or negative for error
+ *
* Utility for the outgoing postcopy code.
* Calls postcopy_send_discard_bm_ram for each RAMBlock
* passing it bitmap indexes and name.
- * Returns: 0 on success
* (qemu_ram_foreach_block ends up passing unscaled lengths
* which would mean postcopy code would have to deal with target page)
+ *
+ * @ms: current migration state
*/
static int postcopy_each_ram_send_discard(MigrationState *ms)
{
struct RAMBlock *block;
int ret;
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
- unsigned long first = block->offset >> TARGET_PAGE_BITS;
- PostcopyDiscardState *pds = postcopy_discard_send_init(ms,
- first,
- block->idstr);
+ RAMBLOCK_FOREACH(block) {
+ PostcopyDiscardState *pds =
+ postcopy_discard_send_init(ms, block->idstr);
/*
* Postcopy sends chunks of bitmap over the wire, but it
* just needs indexes at this point, avoids it having
* target page specific code.
*/
- ret = postcopy_send_discard_bm_ram(ms, pds, first,
- block->used_length >> TARGET_PAGE_BITS);
+ ret = postcopy_send_discard_bm_ram(ms, pds, block);
postcopy_discard_send_finish(ms, pds);
if (ret) {
return ret;
return 0;
}
-/*
- * Helper for postcopy_chunk_hostpages; it's called twice to cleanup
- * the two bitmaps, that are similar, but one is inverted.
+/**
+ * postcopy_chunk_hostpages_pass: canocalize bitmap in hostpages
+ *
+ * Helper for postcopy_chunk_hostpages; it's called twice to
+ * canonicalize the two bitmaps, that are similar, but one is
+ * inverted.
*
- * We search for runs of target-pages that don't start or end on a
- * host page boundary;
- * unsent_pass=true: Cleans up partially unsent host pages by searching
- * the unsentmap
- * unsent_pass=false: Cleans up partially dirty host pages by searching
- * the main migration bitmap
+ * Postcopy requires that all target pages in a hostpage are dirty or
+ * clean, not a mix. This function canonicalizes the bitmaps.
*
+ * @ms: current migration state
+ * @unsent_pass: if true we need to canonicalize partially unsent host pages
+ * otherwise we need to canonicalize partially dirty host pages
+ * @block: block that contains the page we want to canonicalize
+ * @pds: state for postcopy
*/
static void postcopy_chunk_hostpages_pass(MigrationState *ms, bool unsent_pass,
RAMBlock *block,
PostcopyDiscardState *pds)
{
- unsigned long *bitmap;
- unsigned long *unsentmap;
+ RAMState *rs = &ram_state;
+ unsigned long *bitmap = block->bmap;
+ unsigned long *unsentmap = block->unsentmap;
unsigned int host_ratio = block->page_size / TARGET_PAGE_SIZE;
- unsigned long first = block->offset >> TARGET_PAGE_BITS;
- unsigned long len = block->used_length >> TARGET_PAGE_BITS;
- unsigned long last = first + (len - 1);
+ unsigned long pages = block->used_length >> TARGET_PAGE_BITS;
unsigned long run_start;
if (block->page_size == TARGET_PAGE_SIZE) {
return;
}
- bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap;
-
if (unsent_pass) {
/* Find a sent page */
- run_start = find_next_zero_bit(unsentmap, last + 1, first);
+ run_start = find_next_zero_bit(unsentmap, pages, 0);
} else {
/* Find a dirty page */
- run_start = find_next_bit(bitmap, last + 1, first);
+ run_start = find_next_bit(bitmap, pages, 0);
}
- while (run_start <= last) {
+ while (run_start < pages) {
bool do_fixup = false;
unsigned long fixup_start_addr;
unsigned long host_offset;
/* Find the end of this run */
unsigned long run_end;
if (unsent_pass) {
- run_end = find_next_bit(unsentmap, last + 1, run_start + 1);
+ run_end = find_next_bit(unsentmap, pages, run_start + 1);
} else {
- run_end = find_next_zero_bit(bitmap, last + 1, run_start + 1);
+ run_end = find_next_zero_bit(bitmap, pages, run_start + 1);
}
/*
* If the end isn't at the start of a host page, then the
* Remark them as dirty, updating the count for any pages
* that weren't previously dirty.
*/
- migration_dirty_pages += !test_and_set_bit(page, bitmap);
+ rs->migration_dirty_pages += !test_and_set_bit(page, bitmap);
}
}
if (unsent_pass) {
/* Find the next sent page for the next iteration */
- run_start = find_next_zero_bit(unsentmap, last + 1,
- run_start);
+ run_start = find_next_zero_bit(unsentmap, pages, run_start);
} else {
/* Find the next dirty page for the next iteration */
- run_start = find_next_bit(bitmap, last + 1, run_start);
+ run_start = find_next_bit(bitmap, pages, run_start);
}
}
}
-/*
+/**
+ * postcopy_chuck_hostpages: discrad any partially sent host page
+ *
* Utility for the outgoing postcopy code.
*
* Discard any partially sent host-page size chunks, mark any partially
* dirty host-page size chunks as all dirty. In this case the host-page
* is the host-page for the particular RAMBlock, i.e. it might be a huge page
*
- * Returns: 0 on success
+ * Returns zero on success
+ *
+ * @ms: current migration state
+ * @block: block we want to work with
*/
-static int postcopy_chunk_hostpages(MigrationState *ms)
+static int postcopy_chunk_hostpages(MigrationState *ms, RAMBlock *block)
{
- struct RAMBlock *block;
-
- /* Easiest way to make sure we don't resume in the middle of a host-page */
- last_seen_block = NULL;
- last_sent_block = NULL;
- last_offset = 0;
-
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
- unsigned long first = block->offset >> TARGET_PAGE_BITS;
-
- PostcopyDiscardState *pds =
- postcopy_discard_send_init(ms, first, block->idstr);
+ PostcopyDiscardState *pds =
+ postcopy_discard_send_init(ms, block->idstr);
- /* First pass: Discard all partially sent host pages */
- postcopy_chunk_hostpages_pass(ms, true, block, pds);
- /*
- * Second pass: Ensure that all partially dirty host pages are made
- * fully dirty.
- */
- postcopy_chunk_hostpages_pass(ms, false, block, pds);
-
- postcopy_discard_send_finish(ms, pds);
- } /* ram_list loop */
+ /* First pass: Discard all partially sent host pages */
+ postcopy_chunk_hostpages_pass(ms, true, block, pds);
+ /*
+ * Second pass: Ensure that all partially dirty host pages are made
+ * fully dirty.
+ */
+ postcopy_chunk_hostpages_pass(ms, false, block, pds);
+ postcopy_discard_send_finish(ms, pds);
return 0;
}
-/*
+/**
+ * ram_postcopy_send_discard_bitmap: transmit the discard bitmap
+ *
+ * Returns zero on success
+ *
* Transmit the set of pages to be discarded after precopy to the target
* these are pages that:
* a) Have been previously transmitted but are now dirty again
* any pages on the destination that have been mapped by background
* tasks get discarded (transparent huge pages is the specific concern)
* Hopefully this is pretty sparse
+ *
+ * @ms: current migration state
*/
int ram_postcopy_send_discard_bitmap(MigrationState *ms)
{
+ RAMState *rs = &ram_state;
+ RAMBlock *block;
int ret;
- unsigned long *bitmap, *unsentmap;
rcu_read_lock();
/* This should be our last sync, the src is now paused */
- migration_bitmap_sync();
-
- unsentmap = atomic_rcu_read(&migration_bitmap_rcu)->unsentmap;
- if (!unsentmap) {
- /* We don't have a safe way to resize the sentmap, so
- * if the bitmap was resized it will be NULL at this
- * point.
- */
- error_report("migration ram resized during precopy phase");
- rcu_read_unlock();
- return -EINVAL;
- }
+ migration_bitmap_sync(rs);
- /* Deal with TPS != HPS and huge pages */
- ret = postcopy_chunk_hostpages(ms);
- if (ret) {
- rcu_read_unlock();
- return ret;
- }
-
- /*
- * Update the unsentmap to be unsentmap = unsentmap | dirty
- */
- bitmap = atomic_rcu_read(&migration_bitmap_rcu)->bmap;
- bitmap_or(unsentmap, unsentmap, bitmap,
- last_ram_offset() >> TARGET_PAGE_BITS);
+ /* Easiest way to make sure we don't resume in the middle of a host-page */
+ rs->last_seen_block = NULL;
+ rs->last_sent_block = NULL;
+ rs->last_page = 0;
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ unsigned long pages = block->used_length >> TARGET_PAGE_BITS;
+ unsigned long *bitmap = block->bmap;
+ unsigned long *unsentmap = block->unsentmap;
+
+ if (!unsentmap) {
+ /* We don't have a safe way to resize the sentmap, so
+ * if the bitmap was resized it will be NULL at this
+ * point.
+ */
+ error_report("migration ram resized during precopy phase");
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+ /* Deal with TPS != HPS and huge pages */
+ ret = postcopy_chunk_hostpages(ms, block);
+ if (ret) {
+ rcu_read_unlock();
+ return ret;
+ }
- trace_ram_postcopy_send_discard_bitmap();
+ /*
+ * Update the unsentmap to be unsentmap = unsentmap | dirty
+ */
+ bitmap_or(unsentmap, unsentmap, bitmap, pages);
#ifdef DEBUG_POSTCOPY
- ram_debug_dump_bitmap(unsentmap, true);
+ ram_debug_dump_bitmap(unsentmap, true, pages);
#endif
+ }
+ trace_ram_postcopy_send_discard_bitmap();
ret = postcopy_each_ram_send_discard(ms);
rcu_read_unlock();
return ret;
}
-/*
- * At the start of the postcopy phase of migration, any now-dirty
- * precopied pages are discarded.
+/**
+ * ram_discard_range: discard dirtied pages at the beginning of postcopy
*
- * start, length describe a byte address range within the RAMBlock
+ * Returns zero on success
*
- * Returns 0 on success.
+ * @rbname: name of the RAMBlock of the request. NULL means the
+ * same that last one.
+ * @start: RAMBlock starting page
+ * @length: RAMBlock size
*/
-int ram_discard_range(MigrationIncomingState *mis,
- const char *block_name,
- uint64_t start, size_t length)
+int ram_discard_range(const char *rbname, uint64_t start, size_t length)
{
int ret = -1;
- trace_ram_discard_range(block_name, start, length);
+ trace_ram_discard_range(rbname, start, length);
rcu_read_lock();
- RAMBlock *rb = qemu_ram_block_by_name(block_name);
+ RAMBlock *rb = qemu_ram_block_by_name(rbname);
if (!rb) {
- error_report("ram_discard_range: Failed to find block '%s'",
- block_name);
+ error_report("ram_discard_range: Failed to find block '%s'", rbname);
goto err;
}
return ret;
}
-static int ram_save_init_globals(void)
+static int ram_state_init(RAMState *rs)
{
- int64_t ram_bitmap_pages; /* Size of bitmap in pages, including gaps */
-
- dirty_rate_high_cnt = 0;
- bitmap_sync_count = 0;
- migration_bitmap_sync_init();
- qemu_mutex_init(&migration_bitmap_mutex);
+ memset(rs, 0, sizeof(*rs));
+ qemu_mutex_init(&rs->bitmap_mutex);
+ qemu_mutex_init(&rs->src_page_req_mutex);
+ QSIMPLEQ_INIT(&rs->src_page_requests);
if (migrate_use_xbzrle()) {
XBZRLE_cache_lock();
XBZRLE.encoded_buf = NULL;
return -1;
}
-
- acct_clear();
}
/* For memory_global_dirty_log_start below. */
qemu_mutex_lock_ramlist();
rcu_read_lock();
- bytes_transferred = 0;
- reset_ram_globals();
+ ram_state_reset(rs);
- migration_bitmap_rcu = g_new0(struct BitmapRcu, 1);
/* Skip setting bitmap if there is no RAM */
if (ram_bytes_total()) {
- ram_bitmap_pages = last_ram_offset() >> TARGET_PAGE_BITS;
- migration_bitmap_rcu->bmap = bitmap_new(ram_bitmap_pages);
- bitmap_set(migration_bitmap_rcu->bmap, 0, ram_bitmap_pages);
+ RAMBlock *block;
- if (migrate_postcopy_ram()) {
- migration_bitmap_rcu->unsentmap = bitmap_new(ram_bitmap_pages);
- bitmap_set(migration_bitmap_rcu->unsentmap, 0, ram_bitmap_pages);
+ QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ unsigned long pages = block->max_length >> TARGET_PAGE_BITS;
+
+ block->bmap = bitmap_new(pages);
+ bitmap_set(block->bmap, 0, pages);
+ if (migrate_postcopy_ram()) {
+ block->unsentmap = bitmap_new(pages);
+ bitmap_set(block->unsentmap, 0, pages);
+ }
}
}
* Count the total number of pages used by ram blocks not including any
* gaps due to alignment or unplugs.
*/
- migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS;
+ rs->migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS;
memory_global_dirty_log_start();
- migration_bitmap_sync();
+ migration_bitmap_sync(rs);
qemu_mutex_unlock_ramlist();
qemu_mutex_unlock_iothread();
rcu_read_unlock();
return 0;
}
-/* Each of ram_save_setup, ram_save_iterate and ram_save_complete has
+/*
+ * Each of ram_save_setup, ram_save_iterate and ram_save_complete has
* long-running RCU critical section. When rcu-reclaims in the code
* start to become numerous it will be necessary to reduce the
* granularity of these critical sections.
*/
+/**
+ * ram_save_setup: Setup RAM for migration
+ *
+ * Returns zero to indicate success and negative for error
+ *
+ * @f: QEMUFile where to send the data
+ * @opaque: RAMState pointer
+ */
static int ram_save_setup(QEMUFile *f, void *opaque)
{
+ RAMState *rs = opaque;
RAMBlock *block;
/* migration has already setup the bitmap, reuse it. */
if (!migration_in_colo_state()) {
- if (ram_save_init_globals() < 0) {
+ if (ram_state_init(rs) < 0) {
return -1;
}
}
+ rs->f = f;
rcu_read_lock();
qemu_put_be64(f, ram_bytes_total() | RAM_SAVE_FLAG_MEM_SIZE);
- QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
+ RAMBLOCK_FOREACH(block) {
qemu_put_byte(f, strlen(block->idstr));
qemu_put_buffer(f, (uint8_t *)block->idstr, strlen(block->idstr));
qemu_put_be64(f, block->used_length);
return 0;
}
+/**
+ * ram_save_iterate: iterative stage for migration
+ *
+ * Returns zero to indicate success and negative for error
+ *
+ * @f: QEMUFile where to send the data
+ * @opaque: RAMState pointer
+ */
static int ram_save_iterate(QEMUFile *f, void *opaque)
{
+ RAMState *rs = opaque;
int ret;
int i;
int64_t t0;
int done = 0;
rcu_read_lock();
- if (ram_list.version != last_version) {
- reset_ram_globals();
+ if (ram_list.version != rs->last_version) {
+ ram_state_reset(rs);
}
/* Read version before ram_list.blocks */
while ((ret = qemu_file_rate_limit(f)) == 0) {
int pages;
- pages = ram_find_and_save_block(f, false, &bytes_transferred);
+ pages = ram_find_and_save_block(rs, false);
/* no more pages to sent */
if (pages == 0) {
done = 1;
break;
}
- acct_info.iterations++;
+ rs->iterations++;
/* we want to check in the 1st loop, just in case it was the 1st time
and we had to sync the dirty bitmap.
}
i++;
}
- flush_compressed_data(f);
+ flush_compressed_data(rs);
rcu_read_unlock();
/*
ram_control_after_iterate(f, RAM_CONTROL_ROUND);
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
- bytes_transferred += 8;
+ rs->bytes_transferred += 8;
ret = qemu_file_get_error(f);
if (ret < 0) {
return done;
}
-/* Called with iothread lock */
+/**
+ * ram_save_complete: function called to send the remaining amount of ram
+ *
+ * Returns zero to indicate success
+ *
+ * Called with iothread lock
+ *
+ * @f: QEMUFile where to send the data
+ * @opaque: RAMState pointer
+ */
static int ram_save_complete(QEMUFile *f, void *opaque)
{
+ RAMState *rs = opaque;
+
rcu_read_lock();
- if (!migration_in_postcopy(migrate_get_current())) {
- migration_bitmap_sync();
+ if (!migration_in_postcopy()) {
+ migration_bitmap_sync(rs);
}
ram_control_before_iterate(f, RAM_CONTROL_FINISH);
while (true) {
int pages;
- pages = ram_find_and_save_block(f, !migration_in_colo_state(),
- &bytes_transferred);
+ pages = ram_find_and_save_block(rs, !migration_in_colo_state());
/* no more blocks to sent */
if (pages == 0) {
break;
}
}
- flush_compressed_data(f);
+ flush_compressed_data(rs);
ram_control_after_iterate(f, RAM_CONTROL_FINISH);
rcu_read_unlock();
uint64_t *non_postcopiable_pending,
uint64_t *postcopiable_pending)
{
+ RAMState *rs = opaque;
uint64_t remaining_size;
- remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE;
+ remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE;
- if (!migration_in_postcopy(migrate_get_current()) &&
+ if (!migration_in_postcopy() &&
remaining_size < max_size) {
qemu_mutex_lock_iothread();
rcu_read_lock();
- migration_bitmap_sync();
+ migration_bitmap_sync(rs);
rcu_read_unlock();
qemu_mutex_unlock_iothread();
- remaining_size = ram_save_remaining() * TARGET_PAGE_SIZE;
+ remaining_size = rs->migration_dirty_pages * TARGET_PAGE_SIZE;
}
/* We can do postcopy, and all the data is postcopiable */
return 0;
}
-/* Must be called from within a rcu critical section.
+/**
+ * ram_block_from_stream: read a RAMBlock id from the migration stream
+ *
+ * Must be called from within a rcu critical section.
+ *
* Returns a pointer from within the RCU-protected ram_list.
- */
-/*
- * Read a RAMBlock ID from the stream f.
*
- * f: Stream to read from
- * flags: Page flags (mostly to see if it's a continuation of previous block)
+ * @f: QEMUFile where to read the data from
+ * @flags: Page flags (mostly to see if it's a continuation of previous block)
*/
-static inline RAMBlock *ram_block_from_stream(QEMUFile *f,
- int flags)
+static inline RAMBlock *ram_block_from_stream(QEMUFile *f, int flags)
{
static RAMBlock *block = NULL;
char id[256];
return block->host + offset;
}
-/*
+/**
+ * ram_handle_compressed: handle the zero page case
+ *
* If a page (or a whole RDMA chunk) has been
* determined to be zero, then zap it.
+ *
+ * @host: host address for the zero page
+ * @ch: what the page is filled from. We only support zero
+ * @size: size of the zero page
*/
void ram_handle_compressed(void *host, uint8_t ch, uint64_t size)
{
qemu_mutex_unlock(&decomp_done_lock);
}
-/*
- * Allocate data structures etc needed by incoming migration with postcopy-ram
- * postcopy-ram's similarly names postcopy_ram_incoming_init does the work
+/**
+ * ram_postcopy_incoming_init: allocate postcopy data structures
+ *
+ * Returns 0 for success and negative if there was one error
+ *
+ * @mis: current migration incoming state
+ *
+ * Allocate data structures etc needed by incoming migration with
+ * postcopy-ram. postcopy-ram's similarly names
+ * postcopy_ram_incoming_init does the work.
*/
int ram_postcopy_incoming_init(MigrationIncomingState *mis)
{
- size_t ram_pages = last_ram_offset() >> TARGET_PAGE_BITS;
+ unsigned long ram_pages = last_ram_page();
return postcopy_ram_incoming_init(mis, ram_pages);
}
-/*
+/**
+ * ram_load_postcopy: load a page in postcopy case
+ *
+ * Returns 0 for success or -errno in case of error
+ *
* Called in postcopy mode by ram_load().
* rcu_read_lock is taken prior to this being called.
+ *
+ * @f: QEMUFile where to send the data
*/
static int ram_load_postcopy(QEMUFile *f)
{
trace_ram_load_postcopy_loop((uint64_t)addr, flags);
place_needed = false;
- if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE)) {
+ if (flags & (RAM_SAVE_FLAG_ZERO | RAM_SAVE_FLAG_PAGE)) {
block = ram_block_from_stream(f, flags);
host = host_from_ram_block_offset(block, addr);
last_host = host;
switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
- case RAM_SAVE_FLAG_COMPRESS:
+ case RAM_SAVE_FLAG_ZERO:
ch = qemu_get_byte(f);
memset(page_buffer, ch, TARGET_PAGE_SIZE);
if (ch) {
flags = addr & ~TARGET_PAGE_MASK;
addr &= TARGET_PAGE_MASK;
- if (flags & (RAM_SAVE_FLAG_COMPRESS | RAM_SAVE_FLAG_PAGE |
+ 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);
ret = -EINVAL;
break;
}
+ trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host);
}
switch (flags & ~RAM_SAVE_FLAG_CONTINUE) {
}
break;
- case RAM_SAVE_FLAG_COMPRESS:
+ case RAM_SAVE_FLAG_ZERO:
ch = qemu_get_byte(f);
ram_handle_compressed(host, ch, TARGET_PAGE_SIZE);
break;
void ram_mig_init(void)
{
qemu_mutex_init(&XBZRLE.lock);
- register_savevm_live(NULL, "ram", 0, 4, &savevm_ram_handlers, NULL);
+ register_savevm_live(NULL, "ram", 0, 4, &savevm_ram_handlers, &ram_state);
}
projects / qemu.git / blobdiff