diff options
Diffstat (limited to 'migration/ram.c')
| -rw-r--r-- | migration/ram.c | 166 |
1 files changed, 164 insertions, 2 deletions
diff --git a/migration/ram.c b/migration/ram.c index bc38d98cc3..7e7deec4d8 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -3447,6 +3447,29 @@ static inline void *host_from_ram_block_offset(RAMBlock *block, return block->host + offset; } +static inline void *colo_cache_from_block_offset(RAMBlock *block, + ram_addr_t offset) +{ + if (!offset_in_ramblock(block, offset)) { + return NULL; + } + if (!block->colo_cache) { + error_report("%s: colo_cache is NULL in block :%s", + __func__, block->idstr); + return NULL; + } + + /* + * During colo checkpoint, we need bitmap of these migrated pages. + * It help us to decide which pages in ram cache should be flushed + * into VM's RAM later. + */ + if (!test_and_set_bit(offset >> TARGET_PAGE_BITS, block->bmap)) { + ram_state->migration_dirty_pages++; + } + return block->colo_cache + offset; +} + /** * ram_handle_compressed: handle the zero page case * @@ -3651,6 +3674,88 @@ static void decompress_data_with_multi_threads(QEMUFile *f, qemu_mutex_unlock(&decomp_done_lock); } +/* + * colo cache: this is for secondary VM, we cache the whole + * memory of the secondary VM, it is need to hold the global lock + * to call this helper. + */ +int colo_init_ram_cache(void) +{ + RAMBlock *block; + + rcu_read_lock(); + RAMBLOCK_FOREACH_MIGRATABLE(block) { + block->colo_cache = qemu_anon_ram_alloc(block->used_length, + NULL, + false); + if (!block->colo_cache) { + error_report("%s: Can't alloc memory for COLO cache of block %s," + "size 0x" RAM_ADDR_FMT, __func__, block->idstr, + block->used_length); + goto out_locked; + } + memcpy(block->colo_cache, block->host, block->used_length); + } + rcu_read_unlock(); + /* + * Record the dirty pages that sent by PVM, we use this dirty bitmap together + * with to decide which page in cache should be flushed into SVM's RAM. Here + * we use the same name 'ram_bitmap' as for migration. + */ + if (ram_bytes_total()) { + RAMBlock *block; + + RAMBLOCK_FOREACH_MIGRATABLE(block) { + unsigned long pages = block->max_length >> TARGET_PAGE_BITS; + + block->bmap = bitmap_new(pages); + bitmap_set(block->bmap, 0, pages); + } + } + ram_state = g_new0(RAMState, 1); + ram_state->migration_dirty_pages = 0; + memory_global_dirty_log_start(); + + return 0; + +out_locked: + + RAMBLOCK_FOREACH_MIGRATABLE(block) { + if (block->colo_cache) { + qemu_anon_ram_free(block->colo_cache, block->used_length); + block->colo_cache = NULL; + } + } + + rcu_read_unlock(); + return -errno; +} + +/* It is need to hold the global lock to call this helper */ +void colo_release_ram_cache(void) +{ + RAMBlock *block; + + memory_global_dirty_log_stop(); + RAMBLOCK_FOREACH_MIGRATABLE(block) { + g_free(block->bmap); + block->bmap = NULL; + } + + rcu_read_lock(); + + RAMBLOCK_FOREACH_MIGRATABLE(block) { + if (block->colo_cache) { + qemu_anon_ram_free(block->colo_cache, block->used_length); + block->colo_cache = NULL; + } + } + + rcu_read_unlock(); + g_free(ram_state); + ram_state = NULL; +} + /** * ram_load_setup: Setup RAM for migration incoming side * @@ -3667,6 +3772,7 @@ static int ram_load_setup(QEMUFile *f, void *opaque) xbzrle_load_setup(); ramblock_recv_map_init(); + return 0; } @@ -3687,6 +3793,7 @@ static int ram_load_cleanup(void *opaque) g_free(rb->receivedmap); rb->receivedmap = NULL; } + return 0; } @@ -3869,6 +3976,46 @@ static bool postcopy_is_running(void) return ps >= POSTCOPY_INCOMING_LISTENING && ps < POSTCOPY_INCOMING_END; } +/* + * Flush content of RAM cache into SVM's memory. + * Only flush the pages that be dirtied by PVM or SVM or both. + */ +static void colo_flush_ram_cache(void) +{ + RAMBlock *block = NULL; + void *dst_host; + void *src_host; + unsigned long offset = 0; + + memory_global_dirty_log_sync(); + rcu_read_lock(); + RAMBLOCK_FOREACH_MIGRATABLE(block) { + migration_bitmap_sync_range(ram_state, block, 0, block->used_length); + } + rcu_read_unlock(); + + trace_colo_flush_ram_cache_begin(ram_state->migration_dirty_pages); + rcu_read_lock(); + block = QLIST_FIRST_RCU(&ram_list.blocks); + + while (block) { + offset = migration_bitmap_find_dirty(ram_state, block, offset); + + if (offset << TARGET_PAGE_BITS >= block->used_length) { + offset = 0; + block = QLIST_NEXT_RCU(block, next); + } else { + migration_bitmap_clear_dirty(ram_state, block, offset); + dst_host = block->host + (offset << TARGET_PAGE_BITS); + src_host = block->colo_cache + (offset << TARGET_PAGE_BITS); + memcpy(dst_host, src_host, TARGET_PAGE_SIZE); + } + } + + rcu_read_unlock(); + trace_colo_flush_ram_cache_end(); +} + static int ram_load(QEMUFile *f, void *opaque, int version_id) { int flags = 0, ret = 0, invalid_flags = 0; @@ -3924,13 +4071,24 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) RAM_SAVE_FLAG_COMPRESS_PAGE | RAM_SAVE_FLAG_XBZRLE)) { RAMBlock *block = ram_block_from_stream(f, flags); - host = host_from_ram_block_offset(block, addr); + /* + * After going into COLO, we should load the Page into colo_cache. + */ + if (migration_incoming_in_colo_state()) { + host = colo_cache_from_block_offset(block, addr); + } else { + host = host_from_ram_block_offset(block, addr); + } if (!host) { error_report("Illegal RAM offset " RAM_ADDR_FMT, addr); ret = -EINVAL; break; } - ramblock_recv_bitmap_set(block, host); + + if (!migration_incoming_in_colo_state()) { + ramblock_recv_bitmap_set(block, host); + } + trace_ram_load_loop(block->idstr, (uint64_t)addr, flags, host); } @@ -4034,6 +4192,10 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) ret |= wait_for_decompress_done(); rcu_read_unlock(); trace_ram_load_complete(ret, seq_iter); + + if (!ret && migration_incoming_in_colo_state()) { + colo_flush_ram_cache(); + } return ret; } |