From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:58283) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SfY81-0004wL-E8 for qemu-devel@nongnu.org; Fri, 15 Jun 2012 11:08:07 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1SfY7w-0005Fw-1P for qemu-devel@nongnu.org; Fri, 15 Jun 2012 11:08:01 -0400 Received: from mail-pz0-f45.google.com ([209.85.210.45]:49781) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1SfY7v-0004fx-O0 for qemu-devel@nongnu.org; Fri, 15 Jun 2012 11:07:55 -0400 Received: by mail-pz0-f45.google.com with SMTP id n2so3246681dad.4 for ; Fri, 15 Jun 2012 08:07:54 -0700 (PDT) Sender: Paolo Bonzini From: Paolo Bonzini Date: Fri, 15 Jun 2012 17:05:54 +0200 Message-Id: <1339772759-31004-32-git-send-email-pbonzini@redhat.com> In-Reply-To: <1339772759-31004-1-git-send-email-pbonzini@redhat.com> References: <1339772759-31004-1-git-send-email-pbonzini@redhat.com> Subject: [Qemu-devel] [RFC PATCH 31/36] block: implement dirty bitmap using HBitmap List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: kwolf@redhat.com, stefanha@linux.vnet.ibm.com, lcapitulino@redhat.com This actually uses the dirty bitmap in the block layer, and converts mirroring to use an HBitmapIter. Signed-off-by: Paolo Bonzini --- Makefile.objs | 2 +- block.c | 94 +++++++++----------------------------------------------- block.h | 6 ++-- block/mirror.c | 11 +++++-- block_int.h | 4 +-- 5 files changed, 31 insertions(+), 86 deletions(-) diff --git a/Makefile.objs b/Makefile.objs index cef9933..e5262ff 100644 --- a/Makefile.objs +++ b/Makefile.objs @@ -42,7 +42,7 @@ coroutine-obj-$(CONFIG_WIN32) += coroutine-win32.o block-obj-y = cutils.o cache-utils.o qemu-option.o module.o async.o block-obj-y += nbd.o block.o blockjob.o aio.o aes.o qemu-config.o -block-obj-y += qemu-progress.o qemu-sockets.o +block-obj-y += qemu-progress.o qemu-sockets.o hbitmap.o block-obj-y += $(coroutine-obj-y) $(qobject-obj-y) $(version-obj-y) block-obj-$(CONFIG_POSIX) += posix-aio-compat.o block-obj-$(CONFIG_LINUX_AIO) += linux-aio.o diff --git a/block.c b/block.c index 5b08c5b..a105f9e 100644 --- a/block.c +++ b/block.c @@ -1032,7 +1032,6 @@ 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 */ @@ -1661,36 +1660,6 @@ int bdrv_read(BlockDriverState *bs, int64_t sector_num, return bdrv_rw_co(bs, sector_num, buf, nb_sectors, false); } -#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. @@ -4063,18 +4032,15 @@ 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; } } @@ -4082,67 +4048,37 @@ 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 a4aea47..0d8f21c 100644 --- a/block.h +++ b/block.h @@ -353,13 +353,15 @@ 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 346a0eb..787b763 100644 --- a/block/mirror.c +++ b/block/mirror.c @@ -36,6 +36,7 @@ typedef struct MirrorBlockJob { bool synced; bool complete; int64_t sector_num; + HBitmapIter hbi; void *buf; } MirrorBlockJob; @@ -49,8 +50,14 @@ 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); + 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); trace_mirror_one_iteration(s, s->sector_num); bdrv_reset_dirty(source, s->sector_num, BDRV_SECTORS_PER_DIRTY_CHUNK); @@ -126,7 +133,7 @@ static void coroutine_fn mirror_run(void *opaque) block_job_completed(&s->common, ret); } - 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 599eb37..6d36fe7 100644 --- a/block_int.h +++ b/block_int.h @@ -30,6 +30,7 @@ #include "qemu-coroutine.h" #include "qemu-timer.h" #include "qapi-types.h" +#include "hbitmap.h" #include "monitor.h" #define BLOCK_FLAG_ENCRYPT 1 @@ -259,8 +260,7 @@ 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; -- 1.7.10.2