diff --git a/block/blklogwrites.c b/block/blklogwrites.c index 56154e7325..63bf6b34a9 100644 --- a/block/blklogwrites.c +++ b/block/blklogwrites.c @@ -55,6 +55,7 @@ typedef struct { uint32_t sectorbits; uint64_t cur_log_sector; uint64_t nr_entries; + uint64_t update_interval; } BDRVBlkLogWritesState; static QemuOptsList runtime_opts = { @@ -71,6 +72,11 @@ static QemuOptsList runtime_opts = { .type = QEMU_OPT_SIZE, .help = "Log sector size", }, + { + .name = "log-super-update-interval", + .type = QEMU_OPT_NUMBER, + .help = "Log superblock update interval (# of write requests)", + }, { /* end of list */ } }, }; @@ -234,6 +240,14 @@ static int blk_log_writes_open(BlockDriverState *bs, QDict *options, int flags, s->sectorsize = log_sector_size; s->sectorbits = blk_log_writes_log2(log_sector_size); + s->update_interval = qemu_opt_get_number(opts, "log-super-update-interval", + 4096); + if (!s->update_interval) { + ret = -EINVAL; + error_setg(errp, "Invalid log superblock update interval %"PRIu64, + s->update_interval); + goto fail_log; + } ret = 0; fail_log: @@ -360,8 +374,10 @@ static void coroutine_fn blk_log_writes_co_do_log(BlkLogWritesLogReq *lr) lr->zero_size, 0); } - /* Update super block on flush */ - if (lr->log_ret == 0 && lr->entry.flags & LOG_FLUSH_FLAG) { + /* Update super block on flush or every update interval */ + if (lr->log_ret == 0 && ((lr->entry.flags & LOG_FLUSH_FLAG) + || (s->nr_entries % s->update_interval == 0))) + { struct log_write_super super = { .magic = cpu_to_le64(WRITE_LOG_MAGIC), .version = cpu_to_le64(WRITE_LOG_VERSION), diff --git a/qapi/block-core.json b/qapi/block-core.json index d1753a2ae7..38b31250f9 100644 --- a/qapi/block-core.json +++ b/qapi/block-core.json @@ -3057,13 +3057,17 @@ # @log-sector-size: sector size used in logging writes to @file, determines # granularity of offsets and sizes of writes (default: 512) # +# @log-super-update-interval: interval of write requests after which the log +# super block is updated to disk (default: 4096) +# # Since: 3.0 ## { 'struct': 'BlockdevOptionsBlklogwrites', 'data': { 'file': 'BlockdevRef', 'log': 'BlockdevRef', '*log-sector-size': 'uint32', - '*log-append': 'bool' } } + '*log-append': 'bool', + '*log-super-update-interval': 'uint64' } } ## # @BlockdevOptionsBlkverify: