This actually uses the dirty bitmap in the block layer, and converts
mirroring to use an HBitmapIter.
Reviewed-by: Laszlo Ersek <ler...@redhat.com> (except block/mirror.c parts)
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
Makefile.objs | 2 +-
block.c | 94 ++++++++++------------------------------------------------
block.h | 6 ++--
block/mirror.c | 12 ++++++--
block_int.h | 4 +--
trace-events | 1 +
6 files changed, 33 insertions(+), 86 deletions(-)
diff --git a/Makefile.objs b/Makefile.objs
index 3c7abca..9dc96c3 100644
--- a/Makefile.objs
+++ b/Makefile.objs
@@ -46,7 +46,7 @@ coroutine-obj-$(CONFIG_WIN32) += coroutine-win32.o
# block-obj-y is code used by both qemu system emulation and qemu-img
block-obj-y = iov.o cache-utils.o qemu-option.o module.o async.o
-block-obj-y += nbd.o block.o blockjob.o aes.o qemu-config.o
+block-obj-y += nbd.o block.o blockjob.o aes.o qemu-config.o hbitmap.o
block-obj-y += thread-pool.o qemu-progress.o qemu-sockets.o uri.o notify.o
block-obj-y += $(coroutine-obj-y) $(qobject-obj-y) $(version-obj-y)
block-obj-$(CONFIG_POSIX) += event_notifier-posix.o aio-posix.o
diff --git a/block.c b/block.c
index c05875f..f033c1e 100644
--- a/block.c
+++ b/block.c
@@ -1273,7 +1273,6 @@ 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 */
@@ -2022,36 +2021,6 @@ 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.
@@ -4254,18 +4223,15 @@ 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;
}
}
@@ -4273,67 +4239,37 @@ 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.h b/block.h
index 722c620..6a84350 100644
--- a/block.h
+++ b/block.h
@@ -350,13 +350,15 @@ int bdrv_img_create(const char *filename, const char *fmt,
void bdrv_set_buffer_alignment(BlockDriverState *bs, int align);
void *qemu_blockalign(BlockDriverState *bs, size_t size);
-#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/block/mirror.c b/block/mirror.c
index d6618a4..30bb267 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/block_int.h b/block_int.h
index 9deedb8..364ab2d 100644
--- a/block_int.h
+++ b/block_int.h
@@ -32,6 +32,7 @@
#include "qapi-types.h"
#include "qerror.h"
#include "monitor.h"
+#include "hbitmap.h"
#define BLOCK_FLAG_ENCRYPT 1
#define BLOCK_FLAG_COMPAT6 4
@@ -269,8 +270,7 @@ 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 93e8901..b868ac6 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"
--
1.8.0.1
