From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52165) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bHv6u-0001tl-IY for qemu-devel@nongnu.org; Tue, 28 Jun 2016 11:39:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bHv6q-0001pp-RF for qemu-devel@nongnu.org; Tue, 28 Jun 2016 11:39:35 -0400 References: <1464928382-9650-1-git-send-email-famz@redhat.com> <1464928382-9650-2-git-send-email-famz@redhat.com> <5772999A.4030603@virtuozzo.com> From: Vladimir Sementsov-Ogievskiy Message-ID: <57729A31.1060907@virtuozzo.com> Date: Tue, 28 Jun 2016 18:39:29 +0300 MIME-Version: 1.0 In-Reply-To: <5772999A.4030603@virtuozzo.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH v5 01/10] block: Hide HBitmap in block dirty bitmap interface List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Fam Zheng , qemu-devel@nongnu.org Cc: kwolf@redhat.com, jsnow@redhat.com, qemu-block@nongnu.org, mreitz@redhat.com On 28.06.2016 18:36, Vladimir Sementsov-Ogievskiy wrote: > On 03.06.2016 07:32, Fam Zheng wrote: >> HBitmap is an implementation detail of block dirty bitmap that should >> be hidden >> from users. Introduce a BdrvDirtyBitmapIter to encapsulate the >> underlying >> HBitmapIter. >> >> A small difference in the interface is, before, an HBitmapIter is >> initialized >> in place, now the new BdrvDirtyBitmapIter must be dynamically >> allocated because >> the structure definition is in block/dirty-bitmap.c. >> >> Two current users are converted too. >> >> Signed-off-by: Fam Zheng >> --- >> block/backup.c | 14 ++++++++------ >> block/dirty-bitmap.c | 39 >> +++++++++++++++++++++++++++++++++------ >> block/mirror.c | 24 +++++++++++++----------- >> include/block/dirty-bitmap.h | 7 +++++-- >> include/qemu/typedefs.h | 1 + >> 5 files changed, 60 insertions(+), 25 deletions(-) >> >> diff --git a/block/backup.c b/block/backup.c >> index feeb9f8..ac7ca45 100644 >> --- a/block/backup.c >> +++ b/block/backup.c >> @@ -317,14 +317,14 @@ static int coroutine_fn >> backup_run_incremental(BackupBlockJob *job) >> int64_t end; >> int64_t last_cluster = -1; >> int64_t sectors_per_cluster = cluster_size_sectors(job); >> - HBitmapIter hbi; >> + BdrvDirtyBitmapIter *dbi; >> granularity = bdrv_dirty_bitmap_granularity(job->sync_bitmap); >> clusters_per_iter = MAX((granularity / job->cluster_size), 1); >> - bdrv_dirty_iter_init(job->sync_bitmap, &hbi); >> + dbi = bdrv_dirty_iter_new(job->sync_bitmap, 0); >> /* Find the next dirty sector(s) */ >> - while ((sector = hbitmap_iter_next(&hbi)) != -1) { >> + while ((sector = bdrv_dirty_iter_next(dbi)) != -1) { >> cluster = sector / sectors_per_cluster; >> /* Fake progress updates for any clusters we skipped */ >> @@ -336,7 +336,7 @@ static int coroutine_fn >> backup_run_incremental(BackupBlockJob *job) >> for (end = cluster + clusters_per_iter; cluster < end; >> cluster++) { >> do { >> if (yield_and_check(job)) { >> - return ret; >> + goto out; >> } >> ret = backup_do_cow(job, cluster * >> sectors_per_cluster, >> sectors_per_cluster, >> &error_is_read, >> @@ -344,7 +344,7 @@ static int coroutine_fn >> backup_run_incremental(BackupBlockJob *job) >> if ((ret < 0) && >> backup_error_action(job, error_is_read, -ret) == >> BLOCK_ERROR_ACTION_REPORT) { >> - return ret; >> + goto out; >> } >> } while (ret < 0); >> } >> @@ -352,7 +352,7 @@ static int coroutine_fn >> backup_run_incremental(BackupBlockJob *job) >> /* If the bitmap granularity is smaller than the backup >> granularity, >> * we need to advance the iterator pointer to the next >> cluster. */ >> if (granularity < job->cluster_size) { >> - bdrv_set_dirty_iter(&hbi, cluster * sectors_per_cluster); >> + bdrv_set_dirty_iter(dbi, cluster * sectors_per_cluster); >> } >> last_cluster = cluster - 1; >> @@ -364,6 +364,8 @@ static int coroutine_fn >> backup_run_incremental(BackupBlockJob *job) >> job->common.offset += ((end - last_cluster - 1) * >> job->cluster_size); >> } >> +out: >> + bdrv_dirty_iter_free(dbi); >> return ret; >> } >> diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c >> index 4902ca5..ec073ee 100644 >> --- a/block/dirty-bitmap.c >> +++ b/block/dirty-bitmap.c >> @@ -42,9 +42,15 @@ struct BdrvDirtyBitmap { >> char *name; /* Optional non-empty unique ID */ >> int64_t size; /* Size of the bitmap (Number of >> sectors) */ >> bool disabled; /* Bitmap is read-only */ >> + int active_iterators; /* How many iterators are active */ >> QLIST_ENTRY(BdrvDirtyBitmap) list; >> }; >> +struct BdrvDirtyBitmapIter { >> + HBitmapIter hbi; >> + BdrvDirtyBitmap *bitmap; >> +}; >> + >> BdrvDirtyBitmap *bdrv_find_dirty_bitmap(BlockDriverState *bs, const >> char *name) >> { >> BdrvDirtyBitmap *bm; >> @@ -212,6 +218,7 @@ void bdrv_dirty_bitmap_truncate(BlockDriverState >> *bs) >> QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) { >> assert(!bdrv_dirty_bitmap_frozen(bitmap)); >> + assert(!bitmap->active_iterators); >> hbitmap_truncate(bitmap->bitmap, size); >> bitmap->size = size; >> } >> @@ -224,6 +231,7 @@ static void >> bdrv_do_release_matching_dirty_bitmap(BlockDriverState *bs, >> BdrvDirtyBitmap *bm, *next; >> QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) { >> if ((!bitmap || bm == bitmap) && (!only_named || bm->name)) { >> + assert(!bitmap->active_iterators); >> assert(!bdrv_dirty_bitmap_frozen(bm)); >> QLIST_REMOVE(bm, list); >> hbitmap_free(bm->bitmap); >> @@ -320,9 +328,29 @@ uint32_t >> bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap) >> return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap); >> } >> -void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, HBitmapIter *hbi) >> +BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap, >> + uint64_t first_sector) > > can you use const BdrvDirtyBitmap * pointer ? To allow iterating > through const bitmap, in store_to_file function foe ex. I see, no, because of 'bitmap->active_iterators++'... > >> { >> - hbitmap_iter_init(hbi, bitmap->bitmap, 0); >> + BdrvDirtyBitmapIter *iter = g_new(BdrvDirtyBitmapIter, 1); >> + hbitmap_iter_init(&iter->hbi, bitmap->bitmap, first_sector); >> + iter->bitmap = bitmap; >> + bitmap->active_iterators++; >> + return iter; >> +} >> + >> +void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter) >> +{ >> + if (!iter) { >> + return; >> + } >> + assert(iter->bitmap->active_iterators > 0); >> + iter->bitmap->active_iterators--; >> + g_free(iter); >> +} >> + >> +int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter) >> +{ >> + return hbitmap_iter_next(&iter->hbi); >> } >> void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap, >> @@ -373,12 +401,11 @@ void bdrv_set_dirty(BlockDriverState *bs, >> int64_t cur_sector, >> } >> /** >> - * Advance an HBitmapIter to an arbitrary offset. >> + * Advance a BdrvDirtyBitmapIter to an arbitrary offset. >> */ >> -void bdrv_set_dirty_iter(HBitmapIter *hbi, int64_t offset) >> +void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t sector_num) >> { >> - assert(hbi->hb); >> - hbitmap_iter_init(hbi, hbi->hb, offset); >> + hbitmap_iter_init(&iter->hbi, iter->hbi.hb, sector_num); >> } >> int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap) >> diff --git a/block/mirror.c b/block/mirror.c >> index 80fd3c7..1d90aa5 100644 >> --- a/block/mirror.c >> +++ b/block/mirror.c >> @@ -52,7 +52,7 @@ typedef struct MirrorBlockJob { >> int64_t bdev_length; >> unsigned long *cow_bitmap; >> BdrvDirtyBitmap *dirty_bitmap; >> - HBitmapIter hbi; >> + BdrvDirtyBitmapIter *dbi; >> uint8_t *buf; >> QSIMPLEQ_HEAD(, MirrorBuffer) buf_free; >> int buf_free_count; >> @@ -317,10 +317,10 @@ static uint64_t coroutine_fn >> mirror_iteration(MirrorBlockJob *s) >> int64_t end = s->bdev_length / BDRV_SECTOR_SIZE; >> int sectors_per_chunk = s->granularity >> BDRV_SECTOR_BITS; >> - sector_num = hbitmap_iter_next(&s->hbi); >> + sector_num = bdrv_dirty_iter_next(s->dbi); >> if (sector_num < 0) { >> - bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi); >> - sector_num = hbitmap_iter_next(&s->hbi); >> + bdrv_set_dirty_iter(s->dbi, 0); >> + sector_num = bdrv_dirty_iter_next(s->dbi); >> trace_mirror_restart_iter(s, >> bdrv_get_dirty_count(s->dirty_bitmap)); >> assert(sector_num >= 0); >> } >> @@ -334,7 +334,7 @@ static uint64_t coroutine_fn >> mirror_iteration(MirrorBlockJob *s) >> /* Find the number of consective dirty chunks following the >> first dirty >> * one, and wait for in flight requests in them. */ >> while (nb_chunks * sectors_per_chunk < (s->buf_size >> >> BDRV_SECTOR_BITS)) { >> - int64_t hbitmap_next; >> + int64_t next_dirty; >> int64_t next_sector = sector_num + nb_chunks * >> sectors_per_chunk; >> int64_t next_chunk = next_sector / sectors_per_chunk; >> if (next_sector >= end || >> @@ -345,13 +345,13 @@ static uint64_t coroutine_fn >> mirror_iteration(MirrorBlockJob *s) >> break; >> } >> - hbitmap_next = hbitmap_iter_next(&s->hbi); >> - if (hbitmap_next > next_sector || hbitmap_next < 0) { >> + next_dirty = bdrv_dirty_iter_next(s->dbi); >> + if (next_dirty > next_sector || next_dirty < 0) { >> /* The bitmap iterator's cache is stale, refresh it */ >> - bdrv_set_dirty_iter(&s->hbi, next_sector); >> - hbitmap_next = hbitmap_iter_next(&s->hbi); >> + bdrv_set_dirty_iter(s->dbi, next_sector); >> + next_dirty = bdrv_dirty_iter_next(s->dbi); >> } >> - assert(hbitmap_next == next_sector); >> + assert(next_dirty == next_sector); >> nb_chunks++; >> } >> @@ -601,7 +601,8 @@ static void coroutine_fn mirror_run(void *opaque) >> } >> } >> - bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi); >> + assert(!s->dbi); >> + s->dbi = bdrv_dirty_iter_new(s->dirty_bitmap, 0); >> for (;;) { >> uint64_t delay_ns = 0; >> int64_t cnt; >> @@ -712,6 +713,7 @@ immediate_exit: >> qemu_vfree(s->buf); >> g_free(s->cow_bitmap); >> g_free(s->in_flight_bitmap); >> + bdrv_dirty_iter_free(s->dbi); >> bdrv_release_dirty_bitmap(bs, s->dirty_bitmap); >> data = g_malloc(sizeof(*data)); >> diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h >> index 80afe60..2ea601b 100644 >> --- a/include/block/dirty-bitmap.h >> +++ b/include/block/dirty-bitmap.h >> @@ -36,8 +36,11 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap, >> int64_t cur_sector, int nr_sectors); >> void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap, >> int64_t cur_sector, int nr_sectors); >> -void bdrv_dirty_iter_init(BdrvDirtyBitmap *bitmap, struct >> HBitmapIter *hbi); >> -void bdrv_set_dirty_iter(struct HBitmapIter *hbi, int64_t offset); >> +BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap, >> + uint64_t first_sector); >> +void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter); >> +int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter); >> +void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t sector_num); >> int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap); >> void bdrv_dirty_bitmap_truncate(BlockDriverState *bs); >> diff --git a/include/qemu/typedefs.h b/include/qemu/typedefs.h >> index b113fcf..1b8c30a 100644 >> --- a/include/qemu/typedefs.h >> +++ b/include/qemu/typedefs.h >> @@ -11,6 +11,7 @@ typedef struct AioContext AioContext; >> typedef struct AllwinnerAHCIState AllwinnerAHCIState; >> typedef struct AudioState AudioState; >> typedef struct BdrvDirtyBitmap BdrvDirtyBitmap; >> +typedef struct BdrvDirtyBitmapIter BdrvDirtyBitmapIter; >> typedef struct BlockBackend BlockBackend; >> typedef struct BlockBackendRootState BlockBackendRootState; >> typedef struct BlockDriverState BlockDriverState; > > -- Best regards, Vladimir