uint64_t num_packets;
/* pages sent through this channel */
uint64_t num_pages;
- /* syncs main thread and channels */
- QemuSemaphore sem_sync;
} MultiFDSendParams;
typedef struct {
QemuMutex mutex;
/* is this channel thread running */
bool running;
+ /* should this thread finish */
+ bool quit;
/* array of pages to receive */
MultiFDPages_t *pages;
/* packet allocated len */
struct {
MultiFDSendParams *params;
- /* number of created threads */
- int count;
/* array of pages to sent */
MultiFDPages_t *pages;
/* syncs main thread and channels */
* false.
*/
-static void multifd_send_pages(void)
+static int multifd_send_pages(RAMState *rs)
{
int i;
static int next_channel;
p = &multifd_send_state->params[i];
qemu_mutex_lock(&p->mutex);
+ if (p->quit) {
+ error_report("%s: channel %d has already quit!", __func__, i);
+ qemu_mutex_unlock(&p->mutex);
+ return -1;
+ }
if (!p->pending_job) {
p->pending_job++;
next_channel = (i + 1) % migrate_multifd_channels();
multifd_send_state->pages = p->pages;
p->pages = pages;
transferred = ((uint64_t) pages->used) * TARGET_PAGE_SIZE + p->packet_len;
+ qemu_file_update_transfer(rs->f, transferred);
ram_counters.multifd_bytes += transferred;
ram_counters.transferred += transferred;;
qemu_mutex_unlock(&p->mutex);
qemu_sem_post(&p->sem);
+
+ return 1;
}
-static void multifd_queue_page(RAMBlock *block, ram_addr_t offset)
+static int multifd_queue_page(RAMState *rs, RAMBlock *block, ram_addr_t offset)
{
MultiFDPages_t *pages = multifd_send_state->pages;
pages->used++;
if (pages->used < pages->allocated) {
- return;
+ return 1;
}
}
- multifd_send_pages();
+ if (multifd_send_pages(rs) < 0) {
+ return -1;
+ }
if (pages->block != block) {
- multifd_queue_page(block, offset);
+ return multifd_queue_page(rs, block, offset);
}
+
+ return 1;
}
static void multifd_send_terminate_threads(Error *err)
p->c = NULL;
qemu_mutex_destroy(&p->mutex);
qemu_sem_destroy(&p->sem);
- qemu_sem_destroy(&p->sem_sync);
g_free(p->name);
p->name = NULL;
multifd_pages_clear(p->pages);
multifd_send_state = NULL;
}
-static void multifd_send_sync_main(void)
+static void multifd_send_sync_main(RAMState *rs)
{
int i;
return;
}
if (multifd_send_state->pages->used) {
- multifd_send_pages();
+ if (multifd_send_pages(rs) < 0) {
+ error_report("%s: multifd_send_pages fail", __func__);
+ return;
+ }
}
for (i = 0; i < migrate_multifd_channels(); i++) {
MultiFDSendParams *p = &multifd_send_state->params[i];
qemu_mutex_lock(&p->mutex);
+ if (p->quit) {
+ error_report("%s: channel %d has already quit", __func__, i);
+ qemu_mutex_unlock(&p->mutex);
+ return;
+ }
+
p->packet_num = multifd_send_state->packet_num++;
p->flags |= MULTIFD_FLAG_SYNC;
p->pending_job++;
+ qemu_file_update_transfer(rs->f, p->packet_len);
+ ram_counters.multifd_bytes += p->packet_len;
+ ram_counters.transferred += p->packet_len;
qemu_mutex_unlock(&p->mutex);
qemu_sem_post(&p->sem);
}
{
MultiFDSendParams *p = opaque;
Error *local_err = NULL;
- int ret;
+ int ret = 0;
+ uint32_t flags = 0;
trace_multifd_send_thread_start(p->id);
rcu_register_thread();
if (p->pending_job) {
uint32_t used = p->pages->used;
uint64_t packet_num = p->packet_num;
- uint32_t flags = p->flags;
+ flags = p->flags;
p->next_packet_size = used * qemu_target_page_size();
multifd_send_fill_packet(p);
multifd_send_terminate_threads(local_err);
}
+ /*
+ * Error happen, I will exit, but I can't just leave, tell
+ * who pay attention to me.
+ */
+ if (ret != 0) {
+ if (flags & MULTIFD_FLAG_SYNC) {
+ qemu_sem_post(&multifd_send_state->sem_sync);
+ }
+ qemu_sem_post(&multifd_send_state->channels_ready);
+ }
+
qemu_mutex_lock(&p->mutex);
p->running = false;
qemu_mutex_unlock(&p->mutex);
p->running = true;
qemu_thread_create(&p->thread, p->name, multifd_send_thread, p,
QEMU_THREAD_JOINABLE);
-
- atomic_inc(&multifd_send_state->count);
}
}
thread_count = migrate_multifd_channels();
multifd_send_state = g_malloc0(sizeof(*multifd_send_state));
multifd_send_state->params = g_new0(MultiFDSendParams, thread_count);
- atomic_set(&multifd_send_state->count, 0);
multifd_send_state->pages = multifd_pages_init(page_count);
qemu_sem_init(&multifd_send_state->sem_sync, 0);
qemu_sem_init(&multifd_send_state->channels_ready, 0);
qemu_mutex_init(&p->mutex);
qemu_sem_init(&p->sem, 0);
- qemu_sem_init(&p->sem_sync, 0);
p->quit = false;
p->pending_job = 0;
p->id = i;
MultiFDRecvParams *p = &multifd_recv_state->params[i];
qemu_mutex_lock(&p->mutex);
+ p->quit = true;
/* We could arrive here for two reasons:
- normal quit, i.e. everything went fine, just finished
- error quit: We close the channels so the channel threads
MultiFDRecvParams *p = &multifd_recv_state->params[i];
if (p->running) {
+ p->quit = true;
+ /*
+ * multifd_recv_thread may hung at MULTIFD_FLAG_SYNC handle code,
+ * however try to wakeup it without harm in cleanup phase.
+ */
+ qemu_sem_post(&p->sem_sync);
qemu_thread_join(&p->thread);
}
object_unref(OBJECT(p->c));
trace_multifd_recv_sync_main_wait(p->id);
qemu_sem_wait(&multifd_recv_state->sem_sync);
+ }
+ for (i = 0; i < migrate_multifd_channels(); i++) {
+ MultiFDRecvParams *p = &multifd_recv_state->params[i];
+
qemu_mutex_lock(&p->mutex);
if (multifd_recv_state->packet_num < p->packet_num) {
multifd_recv_state->packet_num = p->packet_num;
}
qemu_mutex_unlock(&p->mutex);
- }
- for (i = 0; i < migrate_multifd_channels(); i++) {
- MultiFDRecvParams *p = &multifd_recv_state->params[i];
-
trace_multifd_recv_sync_main_signal(p->id);
qemu_sem_post(&p->sem_sync);
}
uint32_t used;
uint32_t flags;
+ if (p->quit) {
+ break;
+ }
+
ret = qio_channel_read_all_eof(p->c, (void *)p->packet,
p->packet_len, &local_err);
if (ret == 0) { /* EOF */
qemu_mutex_init(&p->mutex);
qemu_sem_init(&p->sem_sync, 0);
+ p->quit = false;
p->id = i;
p->pages = multifd_pages_init(page_count);
p->packet_len = sizeof(MultiFDPacket_t)
encoded_len = xbzrle_encode_buffer(prev_cached_page, XBZRLE.current_buf,
TARGET_PAGE_SIZE, XBZRLE.encoded_buf,
TARGET_PAGE_SIZE);
+
+ /*
+ * Update the cache contents, so that it corresponds to the data
+ * sent, in all cases except where we skip the page.
+ */
+ if (!last_stage && encoded_len != 0) {
+ memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);
+ /*
+ * In the case where we couldn't compress, ensure that the caller
+ * sends the data from the cache, since the guest might have
+ * changed the RAM since we copied it.
+ */
+ *current_data = prev_cached_page;
+ }
+
if (encoded_len == 0) {
trace_save_xbzrle_page_skipping();
return 0;
} else if (encoded_len == -1) {
trace_save_xbzrle_page_overflow();
xbzrle_counters.overflow++;
- /* update data in the cache */
- if (!last_stage) {
- memcpy(prev_cached_page, *current_data, TARGET_PAGE_SIZE);
- *current_data = prev_cached_page;
- }
return -1;
}
- /* we need to update the data in the cache, in order to get the same data */
- if (!last_stage) {
- memcpy(prev_cached_page, XBZRLE.current_buf, TARGET_PAGE_SIZE);
- }
-
/* Send XBZRLE based compressed page */
bytes_xbzrle = save_page_header(rs, rs->f, block,
offset | RAM_SAVE_FLAG_XBZRLE);
bool ret;
qemu_mutex_lock(&rs->bitmap_mutex);
+
+ /*
+ * Clear dirty bitmap if needed. This _must_ be called before we
+ * send any of the page in the chunk because we need to make sure
+ * we can capture further page content changes when we sync dirty
+ * log the next time. So as long as we are going to send any of
+ * the page in the chunk we clear the remote dirty bitmap for all.
+ * Clearing it earlier won't be a problem, but too late will.
+ */
+ if (rb->clear_bmap && clear_bmap_test_and_clear(rb, page)) {
+ uint8_t shift = rb->clear_bmap_shift;
+ hwaddr size = 1ULL << (TARGET_PAGE_BITS + shift);
+ hwaddr start = (page << TARGET_PAGE_BITS) & (-size);
+
+ /*
+ * CLEAR_BITMAP_SHIFT_MIN should always guarantee this... this
+ * can make things easier sometimes since then start address
+ * of the small chunk will always be 64 pages aligned so the
+ * bitmap will always be aligned to unsigned long. We should
+ * even be able to remove this restriction but I'm simply
+ * keeping it.
+ */
+ assert(shift >= 6);
+ trace_migration_bitmap_clear_dirty(rb->idstr, start, size, page);
+ memory_region_clear_dirty_bitmap(rb->mr, start, size);
+ }
+
ret = test_and_clear_bit(page, rb->bmap);
if (ret) {
return ret;
}
-static void migration_bitmap_sync_range(RAMState *rs, RAMBlock *rb,
- ram_addr_t length)
+/* Called with RCU critical section */
+static void ramblock_sync_dirty_bitmap(RAMState *rs, RAMBlock *rb)
{
rs->migration_dirty_pages +=
- cpu_physical_memory_sync_dirty_bitmap(rb, 0, length,
+ cpu_physical_memory_sync_dirty_bitmap(rb, 0, rb->used_length,
&rs->num_dirty_pages_period);
}
qemu_mutex_lock(&rs->bitmap_mutex);
rcu_read_lock();
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
- migration_bitmap_sync_range(rs, block, block->used_length);
+ ramblock_sync_dirty_bitmap(rs, block);
}
ram_counters.remaining = ram_bytes_remaining();
rcu_read_unlock();
static int ram_save_multifd_page(RAMState *rs, RAMBlock *block,
ram_addr_t offset)
{
- multifd_queue_page(block, offset);
+ if (multifd_queue_page(rs, block, offset) < 0) {
+ return -1;
+ }
ram_counters.normal++;
return 1;
}
/**
- * get_queued_page: unqueue a page from the postocpy requests
+ * get_queued_page: unqueue a page from the postcopy requests
*
* Skips pages that are already sent (!dirty)
*
*/
pss->block = block;
pss->page = offset >> TARGET_PAGE_BITS;
+
+ /*
+ * This unqueued page would break the "one round" check, even is
+ * really rare.
+ */
+ pss->complete_round = false;
}
return !!block;
memory_global_dirty_log_stop();
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
+ g_free(block->clear_bmap);
+ block->clear_bmap = NULL;
g_free(block->bmap);
block->bmap = NULL;
g_free(block->unsentmap);
* with the dirtymap; so a '1' means it's either dirty or unsent.
*
* @ms: current migration state
- * @pds: state for postcopy
- * @start: RAMBlock starting page
- * @length: RAMBlock size
+ * @block: RAMBlock to discard
*/
-static int postcopy_send_discard_bm_ram(MigrationState *ms,
- PostcopyDiscardState *pds,
- RAMBlock *block)
+static int postcopy_send_discard_bm_ram(MigrationState *ms, RAMBlock *block)
{
unsigned long end = block->used_length >> TARGET_PAGE_BITS;
unsigned long current;
for (current = 0; current < end; ) {
unsigned long one = find_next_bit(unsentmap, end, current);
+ unsigned long zero, discard_length;
- if (one <= end) {
- unsigned long zero = find_next_zero_bit(unsentmap, end, one + 1);
- unsigned long discard_length;
+ if (one >= end) {
+ break;
+ }
- if (zero >= end) {
- discard_length = end - one;
- } else {
- discard_length = zero - one;
- }
- if (discard_length) {
- postcopy_discard_send_range(ms, pds, one, discard_length);
- }
- current = one + discard_length;
+ zero = find_next_zero_bit(unsentmap, end, one + 1);
+
+ if (zero >= end) {
+ discard_length = end - one;
} else {
- current = one;
+ discard_length = zero - one;
}
+ postcopy_discard_send_range(ms, one, discard_length);
+ current = one + discard_length;
}
return 0;
int ret;
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
- PostcopyDiscardState *pds =
- postcopy_discard_send_init(ms, block->idstr);
+ 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, block);
- postcopy_discard_send_finish(ms, pds);
+ ret = postcopy_send_discard_bm_ram(ms, block);
+ postcopy_discard_send_finish(ms);
if (ret) {
return ret;
}
* @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)
+ RAMBlock *block)
{
RAMState *rs = ram_state;
unsigned long *bitmap = block->bmap;
}
while (run_start < pages) {
- bool do_fixup = false;
- unsigned long fixup_start_addr;
- unsigned long host_offset;
/*
* If the start of this run of pages is in the middle of a host
* page, then we need to fixup this host page.
*/
- host_offset = run_start % host_ratio;
- if (host_offset) {
- do_fixup = true;
- run_start -= host_offset;
- fixup_start_addr = run_start;
- /* For the next pass */
- run_start = run_start + host_ratio;
- } else {
+ if (QEMU_IS_ALIGNED(run_start, host_ratio)) {
/* Find the end of this run */
- unsigned long run_end;
if (unsent_pass) {
- run_end = find_next_bit(unsentmap, pages, run_start + 1);
+ run_start = find_next_bit(unsentmap, pages, run_start + 1);
} else {
- run_end = find_next_zero_bit(bitmap, pages, run_start + 1);
+ run_start = find_next_zero_bit(bitmap, pages, run_start + 1);
}
/*
* If the end isn't at the start of a host page, then the
* run doesn't finish at the end of a host page
* and we need to discard.
*/
- host_offset = run_end % host_ratio;
- if (host_offset) {
- do_fixup = true;
- fixup_start_addr = run_end - host_offset;
- /*
- * This host page has gone, the next loop iteration starts
- * from after the fixup
- */
- run_start = fixup_start_addr + host_ratio;
- } else {
- /*
- * No discards on this iteration, next loop starts from
- * next sent/dirty page
- */
- run_start = run_end + 1;
- }
}
- if (do_fixup) {
+ if (!QEMU_IS_ALIGNED(run_start, host_ratio)) {
unsigned long page;
+ unsigned long fixup_start_addr = QEMU_ALIGN_DOWN(run_start,
+ host_ratio);
+ run_start = QEMU_ALIGN_UP(run_start, host_ratio);
/* Tell the destination to discard this page */
if (unsent_pass || !test_bit(fixup_start_addr, unsentmap)) {
* (any partially sent pages were already discarded
* by the previous unsent_pass)
*/
- postcopy_discard_send_range(ms, pds, fixup_start_addr,
- host_ratio);
+ postcopy_discard_send_range(ms, fixup_start_addr, host_ratio);
}
/* Clean up the bitmap */
}
/**
- * postcopy_chuck_hostpages: discrad any partially sent host page
+ * postcopy_chunk_hostpages: discard any partially sent host page
*
* Utility for the outgoing postcopy code.
*
*/
static int postcopy_chunk_hostpages(MigrationState *ms, RAMBlock *block)
{
- PostcopyDiscardState *pds =
- postcopy_discard_send_init(ms, block->idstr);
+ postcopy_discard_send_init(ms, block->idstr);
/* First pass: Discard all partially sent host pages */
- postcopy_chunk_hostpages_pass(ms, true, block, pds);
+ postcopy_chunk_hostpages_pass(ms, true, block);
/*
* Second pass: Ensure that all partially dirty host pages are made
* fully dirty.
*/
- postcopy_chunk_hostpages_pass(ms, false, block, pds);
+ postcopy_chunk_hostpages_pass(ms, false, block);
- postcopy_discard_send_finish(ms, pds);
+ postcopy_discard_send_finish(ms);
return 0;
}
/*
* Count the total number of pages used by ram blocks not including any
* gaps due to alignment or unplugs.
+ * This must match with the initial values of dirty bitmap.
*/
(*rsp)->migration_dirty_pages = ram_bytes_total() >> TARGET_PAGE_BITS;
-
ram_state_reset(*rsp);
return 0;
static void ram_list_init_bitmaps(void)
{
+ MigrationState *ms = migrate_get_current();
RAMBlock *block;
unsigned long pages;
+ uint8_t shift;
/* Skip setting bitmap if there is no RAM */
if (ram_bytes_total()) {
+ shift = ms->clear_bitmap_shift;
+ if (shift > CLEAR_BITMAP_SHIFT_MAX) {
+ error_report("clear_bitmap_shift (%u) too big, using "
+ "max value (%u)", shift, CLEAR_BITMAP_SHIFT_MAX);
+ shift = CLEAR_BITMAP_SHIFT_MAX;
+ } else if (shift < CLEAR_BITMAP_SHIFT_MIN) {
+ error_report("clear_bitmap_shift (%u) too small, using "
+ "min value (%u)", shift, CLEAR_BITMAP_SHIFT_MIN);
+ shift = CLEAR_BITMAP_SHIFT_MIN;
+ }
+
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
pages = block->max_length >> TARGET_PAGE_BITS;
+ /*
+ * The initial dirty bitmap for migration must be set with all
+ * ones to make sure we'll migrate every guest RAM page to
+ * destination.
+ * Here we set RAMBlock.bmap all to 1 because when rebegin a
+ * new migration after a failed migration, ram_list.
+ * dirty_memory[DIRTY_MEMORY_MIGRATION] don't include the whole
+ * guest memory.
+ */
block->bmap = bitmap_new(pages);
bitmap_set(block->bmap, 0, pages);
+ block->clear_bmap_shift = shift;
+ block->clear_bmap = bitmap_new(clear_bmap_size(pages, shift));
if (migrate_postcopy_ram()) {
block->unsentmap = bitmap_new(pages);
bitmap_set(block->unsentmap, 0, pages);
}
if (migrate_ignore_shared()) {
qemu_put_be64(f, block->mr->addr);
- qemu_put_byte(f, ramblock_is_ignored(block) ? 1 : 0);
}
}
ram_control_before_iterate(f, RAM_CONTROL_SETUP);
ram_control_after_iterate(f, RAM_CONTROL_SETUP);
- multifd_send_sync_main();
+ multifd_send_sync_main(*rsp);
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
qemu_fflush(f);
*/
ram_control_after_iterate(f, RAM_CONTROL_ROUND);
- multifd_send_sync_main();
out:
+ multifd_send_sync_main(rs);
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
qemu_fflush(f);
ram_counters.transferred += 8;
rcu_read_unlock();
- multifd_send_sync_main();
+ multifd_send_sync_main(rs);
qemu_put_be64(f, RAM_SAVE_FLAG_EOS);
qemu_fflush(f);
memory_global_dirty_log_sync();
rcu_read_lock();
RAMBLOCK_FOREACH_NOT_IGNORED(block) {
- migration_bitmap_sync_range(ram_state, block, block->used_length);
+ ramblock_sync_dirty_bitmap(ram_state, block);
}
rcu_read_unlock();
trace_colo_flush_ram_cache_end();
}
-static int ram_load(QEMUFile *f, void *opaque, int version_id)
+/**
+ * ram_load_precopy: load pages in precopy case
+ *
+ * Returns 0 for success or -errno in case of error
+ *
+ * Called in precopy 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_precopy(QEMUFile *f)
{
- int flags = 0, ret = 0, invalid_flags = 0;
- static uint64_t seq_iter;
- int len = 0;
- /*
- * If system is running in postcopy mode, page inserts to host memory must
- * be atomic
- */
- bool postcopy_running = postcopy_is_running();
+ int flags = 0, ret = 0, invalid_flags = 0, len = 0;
/* ADVISE is earlier, it shows the source has the postcopy capability on */
bool postcopy_advised = postcopy_is_advised();
-
- seq_iter++;
-
- if (version_id != 4) {
- ret = -EINVAL;
- }
-
if (!migrate_use_compression()) {
invalid_flags |= RAM_SAVE_FLAG_COMPRESS_PAGE;
}
- /* This RCU critical section can be very long running.
- * When RCU reclaims in the code start to become numerous,
- * it will be necessary to reduce the granularity of this
- * critical section.
- */
- rcu_read_lock();
-
- if (postcopy_running) {
- ret = ram_load_postcopy(f);
- }
- while (!postcopy_running && !ret && !(flags & RAM_SAVE_FLAG_EOS)) {
+ while (!ret && !(flags & RAM_SAVE_FLAG_EOS)) {
ram_addr_t addr, total_ram_bytes;
void *host = NULL;
uint8_t ch;
}
if (migrate_ignore_shared()) {
hwaddr addr = qemu_get_be64(f);
- bool ignored = qemu_get_byte(f);
- if (ignored != ramblock_is_ignored(block)) {
- error_report("RAM block %s should %s be migrated",
- id, ignored ? "" : "not");
- ret = -EINVAL;
- }
if (ramblock_is_ignored(block) &&
block->mr->addr != addr) {
error_report("Mismatched GPAs for block %s "
}
}
+ return ret;
+}
+
+static int ram_load(QEMUFile *f, void *opaque, int version_id)
+{
+ int ret = 0;
+ static uint64_t seq_iter;
+ /*
+ * If system is running in postcopy mode, page inserts to host memory must
+ * be atomic
+ */
+ bool postcopy_running = postcopy_is_running();
+
+ seq_iter++;
+
+ if (version_id != 4) {
+ return -EINVAL;
+ }
+
+ /*
+ * This RCU critical section can be very long running.
+ * When RCU reclaims in the code start to become numerous,
+ * it will be necessary to reduce the granularity of this
+ * critical section.
+ */
+ rcu_read_lock();
+
+ if (postcopy_running) {
+ ret = ram_load_postcopy(f);
+ } else {
+ ret = ram_load_precopy(f);
+ }
+
ret |= wait_for_decompress_done();
rcu_read_unlock();
trace_ram_load_complete(ret, seq_iter);
projects / qemu.git / blobdiff