From e4654d2d9406016d6e4e296ba8db3d118caf9ff6 Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Wed, 13 Nov 2013 18:29:43 +0800 Subject: block: per caller dirty bitmap Previously a BlockDriverState has only one dirty bitmap, so only one caller (e.g. a block job) can keep track of writing. This changes the dirty bitmap to a list and creates a BdrvDirtyBitmap for each caller, the lifecycle is managed with these new functions: bdrv_create_dirty_bitmap bdrv_release_dirty_bitmap Where BdrvDirtyBitmap is a linked list wrapper structure of HBitmap. In place of bdrv_set_dirty_tracking, a BdrvDirtyBitmap pointer argument is added to these functions, since each caller has its own dirty bitmap: bdrv_get_dirty bdrv_dirty_iter_init bdrv_get_dirty_count bdrv_set_dirty and bdrv_reset_dirty prototypes are unchanged but will internally walk the list of all dirty bitmaps and set them one by one. Signed-off-by: Fam Zheng Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block/mirror.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) (limited to 'block/mirror.c') diff --git a/block/mirror.c b/block/mirror.c index 7b95acf88c..6dc27ad35d 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -39,6 +39,7 @@ typedef struct MirrorBlockJob { int64_t granularity; size_t buf_size; unsigned long *cow_bitmap; + BdrvDirtyBitmap *dirty_bitmap; HBitmapIter hbi; uint8_t *buf; QSIMPLEQ_HEAD(, MirrorBuffer) buf_free; @@ -145,9 +146,10 @@ static void coroutine_fn mirror_iteration(MirrorBlockJob *s) s->sector_num = hbitmap_iter_next(&s->hbi); if (s->sector_num < 0) { - bdrv_dirty_iter_init(source, &s->hbi); + bdrv_dirty_iter_init(source, s->dirty_bitmap, &s->hbi); s->sector_num = hbitmap_iter_next(&s->hbi); - trace_mirror_restart_iter(s, bdrv_get_dirty_count(source)); + trace_mirror_restart_iter(s, + bdrv_get_dirty_count(source, s->dirty_bitmap)); assert(s->sector_num >= 0); } @@ -183,7 +185,7 @@ static void coroutine_fn mirror_iteration(MirrorBlockJob *s) do { int added_sectors, added_chunks; - if (!bdrv_get_dirty(source, next_sector) || + if (!bdrv_get_dirty(source, s->dirty_bitmap, next_sector) || test_bit(next_chunk, s->in_flight_bitmap)) { assert(nb_sectors > 0); break; @@ -249,7 +251,8 @@ static void coroutine_fn mirror_iteration(MirrorBlockJob *s) /* Advance the HBitmapIter in parallel, so that we do not examine * the same sector twice. */ - if (next_sector > hbitmap_next_sector && bdrv_get_dirty(source, next_sector)) { + if (next_sector > hbitmap_next_sector + && bdrv_get_dirty(source, s->dirty_bitmap, next_sector)) { hbitmap_next_sector = hbitmap_iter_next(&s->hbi); } @@ -355,7 +358,7 @@ static void coroutine_fn mirror_run(void *opaque) } } - bdrv_dirty_iter_init(bs, &s->hbi); + bdrv_dirty_iter_init(bs, s->dirty_bitmap, &s->hbi); last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME); for (;;) { uint64_t delay_ns; @@ -367,7 +370,7 @@ static void coroutine_fn mirror_run(void *opaque) goto immediate_exit; } - cnt = bdrv_get_dirty_count(bs); + cnt = bdrv_get_dirty_count(bs, s->dirty_bitmap); /* Note that even when no rate limit is applied we need to yield * periodically with no pending I/O so that qemu_aio_flush() returns. @@ -409,7 +412,7 @@ static void coroutine_fn mirror_run(void *opaque) should_complete = s->should_complete || block_job_is_cancelled(&s->common); - cnt = bdrv_get_dirty_count(bs); + cnt = bdrv_get_dirty_count(bs, s->dirty_bitmap); } } @@ -424,7 +427,7 @@ static void coroutine_fn mirror_run(void *opaque) */ trace_mirror_before_drain(s, cnt); bdrv_drain_all(); - cnt = bdrv_get_dirty_count(bs); + cnt = bdrv_get_dirty_count(bs, s->dirty_bitmap); } ret = 0; @@ -471,7 +474,7 @@ immediate_exit: qemu_vfree(s->buf); g_free(s->cow_bitmap); g_free(s->in_flight_bitmap); - bdrv_set_dirty_tracking(bs, 0); + bdrv_release_dirty_bitmap(bs, s->dirty_bitmap); bdrv_iostatus_disable(s->target); if (s->should_complete && ret == 0) { if (bdrv_get_flags(s->target) != bdrv_get_flags(s->common.bs)) { @@ -575,7 +578,7 @@ void mirror_start(BlockDriverState *bs, BlockDriverState *target, s->granularity = granularity; s->buf_size = MAX(buf_size, granularity); - bdrv_set_dirty_tracking(bs, granularity); + s->dirty_bitmap = bdrv_create_dirty_bitmap(bs, granularity); bdrv_set_enable_write_cache(s->target, true); bdrv_set_on_error(s->target, on_target_error, on_target_error); bdrv_iostatus_enable(s->target); -- cgit v1.2.1