diff options
author | Paolo Bonzini <pbonzini@redhat.com> | 2013-01-21 17:09:41 +0100 |
---|---|---|
committer | Kevin Wolf <kwolf@redhat.com> | 2013-01-25 18:18:33 +0100 |
commit | 8f0720ecbc3677e13fc7531588fc3831cc972ee4 (patch) | |
tree | e1ab1af2393c1a360b7cfbc34caf1d7f5091a742 | |
parent | e7c033c3fa22a1e42d9ba57fed6ddecfbce3a01c (diff) | |
download | hqemu-8f0720ecbc3677e13fc7531588fc3831cc972ee4.zip hqemu-8f0720ecbc3677e13fc7531588fc3831cc972ee4.tar.gz |
block: implement dirty bitmap using HBitmap
This actually uses the dirty bitmap in the block layer, and converts
mirroring to use an HBitmapIter.
Reviewed-by: Laszlo Ersek <lersek@redhat.com> (except block/mirror.c parts)
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
-rw-r--r-- | block.c | 96 | ||||
-rw-r--r-- | block/mirror.c | 12 | ||||
-rw-r--r-- | include/block/block.h | 6 | ||||
-rw-r--r-- | include/block/block_int.h | 4 | ||||
-rw-r--r-- | trace-events | 1 |
5 files changed, 33 insertions, 86 deletions
@@ -1286,7 +1286,6 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest, bs_dest->iostatus = bs_src->iostatus; /* dirty bitmap */ - bs_dest->dirty_count = bs_src->dirty_count; bs_dest->dirty_bitmap = bs_src->dirty_bitmap; /* job */ @@ -2035,36 +2034,6 @@ int bdrv_read_unthrottled(BlockDriverState *bs, int64_t sector_num, return ret; } -#define BITS_PER_LONG (sizeof(unsigned long) * 8) - -static void set_dirty_bitmap(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, int dirty) -{ - int64_t start, end; - unsigned long val, idx, bit; - - start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK; - end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK; - - for (; start <= end; start++) { - idx = start / BITS_PER_LONG; - bit = start % BITS_PER_LONG; - val = bs->dirty_bitmap[idx]; - if (dirty) { - if (!(val & (1UL << bit))) { - bs->dirty_count++; - val |= 1UL << bit; - } - } else { - if (val & (1UL << bit)) { - bs->dirty_count--; - val &= ~(1UL << bit); - } - } - bs->dirty_bitmap[idx] = val; - } -} - /* Return < 0 if error. Important errors are: -EIO generic I/O error (may happen for all errors) -ENOMEDIUM No media inserted. @@ -4173,7 +4142,7 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num, } if (bs->dirty_bitmap) { - set_dirty_bitmap(bs, sector_num, nb_sectors, 0); + bdrv_reset_dirty(bs, sector_num, nb_sectors); } if (bs->drv->bdrv_co_discard) { @@ -4335,18 +4304,15 @@ void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable) { int64_t bitmap_size; - bs->dirty_count = 0; if (enable) { if (!bs->dirty_bitmap) { - bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS) + - BDRV_SECTORS_PER_DIRTY_CHUNK * BITS_PER_LONG - 1; - bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * BITS_PER_LONG; - - bs->dirty_bitmap = g_new0(unsigned long, bitmap_size); + bitmap_size = (bdrv_getlength(bs) >> BDRV_SECTOR_BITS); + bs->dirty_bitmap = hbitmap_alloc(bitmap_size, + BDRV_LOG_SECTORS_PER_DIRTY_CHUNK); } } else { if (bs->dirty_bitmap) { - g_free(bs->dirty_bitmap); + hbitmap_free(bs->dirty_bitmap); bs->dirty_bitmap = NULL; } } @@ -4354,67 +4320,37 @@ void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable) int bdrv_get_dirty(BlockDriverState *bs, int64_t sector) { - int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK; - - if (bs->dirty_bitmap && - (sector << BDRV_SECTOR_BITS) < bdrv_getlength(bs)) { - return !!(bs->dirty_bitmap[chunk / BITS_PER_LONG] & - (1UL << (chunk % BITS_PER_LONG))); + if (bs->dirty_bitmap) { + return hbitmap_get(bs->dirty_bitmap, sector); } else { return 0; } } -int64_t bdrv_get_next_dirty(BlockDriverState *bs, int64_t sector) +void bdrv_dirty_iter_init(BlockDriverState *bs, HBitmapIter *hbi) { - int64_t chunk; - int bit, elem; - - /* Avoid an infinite loop. */ - assert(bs->dirty_count > 0); - - sector = (sector | (BDRV_SECTORS_PER_DIRTY_CHUNK - 1)) + 1; - chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK; - - QEMU_BUILD_BUG_ON(sizeof(bs->dirty_bitmap[0]) * 8 != BITS_PER_LONG); - elem = chunk / BITS_PER_LONG; - bit = chunk % BITS_PER_LONG; - for (;;) { - if (sector >= bs->total_sectors) { - sector = 0; - bit = elem = 0; - } - if (bit == 0 && bs->dirty_bitmap[elem] == 0) { - sector += BDRV_SECTORS_PER_DIRTY_CHUNK * BITS_PER_LONG; - elem++; - } else { - if (bs->dirty_bitmap[elem] & (1UL << bit)) { - return sector; - } - sector += BDRV_SECTORS_PER_DIRTY_CHUNK; - if (++bit == BITS_PER_LONG) { - bit = 0; - elem++; - } - } - } + hbitmap_iter_init(hbi, bs->dirty_bitmap, 0); } void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors) { - set_dirty_bitmap(bs, cur_sector, nr_sectors, 1); + hbitmap_set(bs->dirty_bitmap, cur_sector, nr_sectors); } void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors) { - set_dirty_bitmap(bs, cur_sector, nr_sectors, 0); + hbitmap_reset(bs->dirty_bitmap, cur_sector, nr_sectors); } int64_t bdrv_get_dirty_count(BlockDriverState *bs) { - return bs->dirty_count; + if (bs->dirty_bitmap) { + return hbitmap_count(bs->dirty_bitmap) >> BDRV_LOG_SECTORS_PER_DIRTY_CHUNK; + } else { + return 0; + } } void bdrv_set_in_use(BlockDriverState *bs, int in_use) diff --git a/block/mirror.c b/block/mirror.c index 6180aa3..20cb1e7 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -36,6 +36,7 @@ typedef struct MirrorBlockJob { bool synced; bool should_complete; int64_t sector_num; + HBitmapIter hbi; uint8_t *buf; } MirrorBlockJob; @@ -62,8 +63,15 @@ static int coroutine_fn mirror_iteration(MirrorBlockJob *s, int64_t end; struct iovec iov; + s->sector_num = hbitmap_iter_next(&s->hbi); + if (s->sector_num < 0) { + bdrv_dirty_iter_init(source, &s->hbi); + s->sector_num = hbitmap_iter_next(&s->hbi); + trace_mirror_restart_iter(s, bdrv_get_dirty_count(source)); + assert(s->sector_num >= 0); + } + end = s->common.len >> BDRV_SECTOR_BITS; - s->sector_num = bdrv_get_next_dirty(source, s->sector_num); nb_sectors = MIN(BDRV_SECTORS_PER_DIRTY_CHUNK, end - s->sector_num); bdrv_reset_dirty(source, s->sector_num, nb_sectors); @@ -136,7 +144,7 @@ static void coroutine_fn mirror_run(void *opaque) } } - s->sector_num = -1; + bdrv_dirty_iter_init(bs, &s->hbi); for (;;) { uint64_t delay_ns; int64_t cnt; diff --git a/include/block/block.h b/include/block/block.h index ffd1936..678fc60 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -351,13 +351,15 @@ void bdrv_set_buffer_alignment(BlockDriverState *bs, int align); void *qemu_blockalign(BlockDriverState *bs, size_t size); bool bdrv_qiov_is_aligned(BlockDriverState *bs, QEMUIOVector *qiov); -#define BDRV_SECTORS_PER_DIRTY_CHUNK 2048 +#define BDRV_SECTORS_PER_DIRTY_CHUNK (1 << BDRV_LOG_SECTORS_PER_DIRTY_CHUNK) +#define BDRV_LOG_SECTORS_PER_DIRTY_CHUNK 11 +struct HBitmapIter; void bdrv_set_dirty_tracking(BlockDriverState *bs, int enable); int bdrv_get_dirty(BlockDriverState *bs, int64_t sector); void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors); void bdrv_reset_dirty(BlockDriverState *bs, int64_t cur_sector, int nr_sectors); -int64_t bdrv_get_next_dirty(BlockDriverState *bs, int64_t sector); +void bdrv_dirty_iter_init(BlockDriverState *bs, struct HBitmapIter *hbi); int64_t bdrv_get_dirty_count(BlockDriverState *bs); void bdrv_enable_copy_on_read(BlockDriverState *bs); diff --git a/include/block/block_int.h b/include/block/block_int.h index f83ffb8..b81c061 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -32,6 +32,7 @@ #include "qapi-types.h" #include "qapi/qmp/qerror.h" #include "monitor/monitor.h" +#include "qemu/hbitmap.h" #define BLOCK_FLAG_ENCRYPT 1 #define BLOCK_FLAG_COMPAT6 4 @@ -275,8 +276,7 @@ struct BlockDriverState { bool iostatus_enabled; BlockDeviceIoStatus iostatus; char device_name[32]; - unsigned long *dirty_bitmap; - int64_t dirty_count; + HBitmap *dirty_bitmap; int in_use; /* users other than guest access, eg. block migration */ QTAILQ_ENTRY(BlockDriverState) list; diff --git a/trace-events b/trace-events index 732cb12..61ed349 100644 --- a/trace-events +++ b/trace-events @@ -79,6 +79,7 @@ commit_start(void *bs, void *base, void *top, void *s, void *co, void *opaque) " # block/mirror.c mirror_start(void *bs, void *s, void *co, void *opaque) "bs %p s %p co %p opaque %p" +mirror_restart_iter(void *s, int64_t cnt) "s %p dirty count %"PRId64 mirror_before_flush(void *s) "s %p" mirror_before_drain(void *s, int64_t cnt) "s %p dirty count %"PRId64 mirror_before_sleep(void *s, int64_t cnt, int synced) "s %p dirty count %"PRId64" synced %d" |