Implement the core logic of the multiple thread compression. At this point, multiple thread compression can't co-work with xbzrle yet.
Signed-off-by: Liang Li <liang.z...@intel.com> Signed-off-by: Yang Zhang <yang.z.zh...@intel.com> --- arch_init.c | 193 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 185 insertions(+), 8 deletions(-) diff --git a/arch_init.c b/arch_init.c index fe062db..17b7f15 100644 --- a/arch_init.c +++ b/arch_init.c @@ -363,18 +363,44 @@ static QemuMutex *comp_done_lock; static QemuCond *comp_done_cond; /* The empty QEMUFileOps will be used by file in CompressParam */ static const QEMUFileOps empty_ops = { }; + +/* one_byte_count is used to count the bytes that is added to + * bytes_transferred but not actually transferred, at the proper + * time, we should sub one_byte_count from bytes_transferred to + * make bytes_transferred accurate. + */ +static int one_byte_count; static bool quit_comp_thread; static bool quit_decomp_thread; static DecompressParam *decomp_param; static QemuThread *decompress_threads; static uint8_t *compressed_data_buf; +static int do_compress_ram_page(CompressParam *param); + static void *do_data_compress(void *opaque) { - while (!quit_comp_thread) { - - /* To be done */ + CompressParam *param = opaque; + while (!quit_comp_thread) { + qemu_mutex_lock(¶m->mutex); + /* Re-check the quit_comp_thread in case of + * terminate_compression_threads is called just before + * qemu_mutex_lock(¶m->mutex) and after + * while(!quit_comp_thread), re-check it here can make + * sure the compression thread terminate as expected. + */ + while (!param->busy && !quit_comp_thread) { + qemu_cond_wait(¶m->cond, ¶m->mutex); + } + qemu_mutex_unlock(¶m->mutex); + if (!quit_comp_thread) { + do_compress_ram_page(param); + } + qemu_mutex_lock(comp_done_lock); + param->busy = false; + qemu_cond_signal(comp_done_cond); + qemu_mutex_unlock(comp_done_lock); } return NULL; @@ -382,9 +408,15 @@ static void *do_data_compress(void *opaque) static inline void terminate_compression_threads(void) { - quit_comp_thread = true; + int idx, thread_count; - /* To be done */ + thread_count = migrate_compress_threads(); + quit_comp_thread = true; + for (idx = 0; idx < thread_count; idx++) { + qemu_mutex_lock(&comp_param[idx].mutex); + qemu_cond_signal(&comp_param[idx].cond); + qemu_mutex_unlock(&comp_param[idx].mutex); + } } void migrate_compress_threads_join(MigrationState *s) @@ -770,12 +802,157 @@ static int ram_save_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset, return bytes_sent; } +static int do_compress_ram_page(CompressParam *param) +{ + int bytes_sent, cont; + int blen; + uint8_t *p; + RAMBlock *block = param->block; + ram_addr_t offset = param->offset; + + cont = (block == last_sent_block) ? RAM_SAVE_FLAG_CONTINUE : 0; + p = memory_region_get_ram_ptr(block->mr) + offset; + + bytes_sent = save_block_hdr(param->file, block, offset, cont, + RAM_SAVE_FLAG_COMPRESS_PAGE); + blen = qemu_put_compression_data(param->file, p, TARGET_PAGE_SIZE, + migrate_compress_level()); + bytes_sent += blen; + atomic_inc(&acct_info.norm_pages); + + return bytes_sent; +} + +static inline void start_compression(CompressParam *param) +{ + qemu_mutex_lock(¶m->mutex); + param->busy = true; + qemu_cond_signal(¶m->cond); + qemu_mutex_unlock(¶m->mutex); +} + + +static uint64_t bytes_transferred; + +static void flush_compressed_data(QEMUFile *f) +{ + int idx, len, thread_count; + + if (!migrate_use_compression()) { + return; + } + thread_count = migrate_compress_threads(); + for (idx = 0; idx < thread_count; idx++) { + if (comp_param[idx].busy) { + qemu_mutex_lock(comp_done_lock); + while (comp_param[idx].busy && !quit_comp_thread) { + qemu_cond_wait(comp_done_cond, comp_done_lock); + } + qemu_mutex_unlock(comp_done_lock); + } + len = qemu_put_qemu_file(f, comp_param[idx].file); + bytes_transferred += len; + } + if ((one_byte_count > 0) && (bytes_transferred > one_byte_count)) { + bytes_transferred -= one_byte_count; + one_byte_count = 0; + } +} + +static inline void set_compress_params(CompressParam *param, RAMBlock *block, + ram_addr_t offset) +{ + param->block = block; + param->offset = offset; +} + +static int compress_page_with_multi_thread(QEMUFile *f, RAMBlock *block, + ram_addr_t offset) +{ + int idx, thread_count, bytes_sent = 0; + + thread_count = migrate_compress_threads(); + qemu_mutex_lock(comp_done_lock); + while (true) { + for (idx = 0; idx < thread_count; idx++) { + if (!comp_param[idx].busy) { + bytes_sent = qemu_put_qemu_file(f, comp_param[idx].file); + set_compress_params(&comp_param[idx], block, offset); + start_compression(&comp_param[idx]); + if (bytes_sent == 0) { + /* set bytes_sent to 1 in this case to prevent migration + * from terminating, this 1 byte will be added to + * bytes_transferred later, minus 1 to keep the + * bytes_transferred accurate */ + bytes_sent = 1; + if (bytes_transferred <= 0) { + one_byte_count++; + } else { + bytes_transferred -= 1; + } + } + break; + } + } + if (bytes_sent > 0) { + break; + } else { + qemu_cond_wait(comp_done_cond, comp_done_lock); + } + } + qemu_mutex_unlock(comp_done_lock); + + return bytes_sent; +} + static int ram_save_compressed_page(QEMUFile *f, RAMBlock *block, ram_addr_t offset, bool last_stage) { int bytes_sent = -1; + MemoryRegion *mr = block->mr; + uint8_t *p; + int ret; + int cont; - /* To be done*/ + p = memory_region_get_ram_ptr(mr) + offset; + cont = (block == last_sent_block) ? RAM_SAVE_FLAG_CONTINUE : 0; + ret = ram_control_save_page(f, block->offset, + offset, TARGET_PAGE_SIZE, &bytes_sent); + if (ret != RAM_SAVE_CONTROL_NOT_SUPP) { + if (ret != RAM_SAVE_CONTROL_DELAYED) { + if (bytes_sent > 0) { + acct_info.norm_pages++; + } else if (bytes_sent == 0) { + acct_info.dup_pages++; + } + } + } else { + /* When starting the process of a new block, the first page of + * the block should be sent out before other pages in the same + * block, and all the pages in last block should have been sent + * 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); + bytes_sent = save_zero_page(f, block, offset, p, cont); + if (bytes_sent == -1) { + set_compress_params(&comp_param[0], block, offset); + /* Use the qemu thread to compress the data to make sure the + * first page is sent out before other pages + */ + bytes_sent = do_compress_ram_page(&comp_param[0]); + if (bytes_sent > 0) { + qemu_put_qemu_file(f, comp_param[0].file); + } + } + } else { + bytes_sent = save_zero_page(f, block, offset, p, cont); + if (bytes_sent == -1) { + bytes_sent = compress_page_with_multi_thread(f, block, offset); + } + } + } return bytes_sent; } @@ -834,8 +1011,6 @@ static int ram_find_and_save_block(QEMUFile *f, bool last_stage) return bytes_sent; } -static uint64_t bytes_transferred; - void acct_update_position(QEMUFile *f, size_t size, bool zero) { uint64_t pages = size / TARGET_PAGE_SIZE; @@ -1043,6 +1218,7 @@ static int ram_save_iterate(QEMUFile *f, void *opaque) i++; } + flush_compressed_data(f); qemu_mutex_unlock_ramlist(); /* @@ -1089,6 +1265,7 @@ static int ram_save_complete(QEMUFile *f, void *opaque) bytes_transferred += bytes_sent; } + flush_compressed_data(f); ram_control_after_iterate(f, RAM_CONTROL_FINISH); migration_end(); -- 1.9.1