[RFC,V4] qemu-img: make convert async

Message ID	1487347224-8667-1-git-send-email-pl@kamp.de (mailing list archive)
State	New, archived
Headers	show Return-Path: <qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org> avast: 1.2.2/17010300. spamassassin: 3.4.1. Clear:RC:1(195.62.97.28):. Processed in 0.082046 secs); 17 Feb 2017 16:00:27 -0000 From: Peter Lieven <pl@kamp.de> To: qemu-devel@nongnu.org Date: Fri, 17 Feb 2017 17:00:24 +0100 Message-Id: <1487347224-8667-1-git-send-email-pl@kamp.de> Subject: [Qemu-devel] [RFC PATCH V4] qemu-img: make convert async Precedence: list Cc: kwolf@redhat.com, famz@redhat.com, qemu-block@nongnu.org, Peter Lieven <pl@kamp.de>, mreitz@redhat.com Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" <qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org>

diff --git a/qemu-img.c b/qemu-img.c index cff22e3..6bac980 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1448,6 +1448,8 @@ enum ImgConvertBlockStatus { BLK_BACKING_FILE, }; +#define MAX_COROUTINES 16 + typedef struct ImgConvertState { BlockBackend **src; int64_t *src_sectors; @@ -1455,15 +1457,25 @@ typedef struct ImgConvertState { int64_t src_cur_offset; int64_t total_sectors; int64_t allocated_sectors; + int64_t allocated_done; + int64_t sector_num; + int64_t wr_offs; enum ImgConvertBlockStatus status; int64_t sector_next_status; BlockBackend *target; bool has_zero_init; bool compressed; bool target_has_backing; + bool wr_in_order; int min_sparse; size_t cluster_sectors; size_t buf_sectors; + int num_coroutines; + int running_coroutines; + Coroutine *co[MAX_COROUTINES]; + int64_t wait_sector_num[MAX_COROUTINES]; + CoMutex lock; + int ret; } ImgConvertState; static void convert_select_part(ImgConvertState *s, int64_t sector_num) @@ -1544,11 +1556,12 @@ static int convert_iteration_sectors(ImgConvertState *s, int64_t sector_num) return n; } -static int convert_read(ImgConvertState *s, int64_t sector_num, int nb_sectors, - uint8_t *buf) +static int convert_co_read(ImgConvertState *s, int64_t sector_num, + int nb_sectors, uint8_t *buf) { - int n; - int ret; + int n, ret; + QEMUIOVector qiov; + struct iovec iov; assert(nb_sectors <= s->buf_sectors); while (nb_sectors > 0) { @@ -1563,9 +1576,13 @@ static int convert_read(ImgConvertState *s, int64_t sector_num, int nb_sectors, bs_sectors = s->src_sectors[s->src_cur]; n = MIN(nb_sectors, bs_sectors - (sector_num - s->src_cur_offset)); - ret = blk_pread(blk, - (sector_num - s->src_cur_offset) << BDRV_SECTOR_BITS, - buf, n << BDRV_SECTOR_BITS); + iov.iov_base = buf; + iov.iov_len = n << BDRV_SECTOR_BITS; + qemu_iovec_init_external(&qiov, &iov, 1); + + ret = blk_co_preadv( + blk, (sector_num - s->src_cur_offset) << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, &qiov, 0); if (ret < 0) { return ret; } @@ -1578,15 +1595,18 @@ static int convert_read(ImgConvertState *s, int64_t sector_num, int nb_sectors, return 0; } -static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, - const uint8_t *buf) + +static int convert_co_write(ImgConvertState *s, int64_t sector_num, + int nb_sectors, uint8_t *buf, + enum ImgConvertBlockStatus status) { int ret; + QEMUIOVector qiov; + struct iovec iov; while (nb_sectors > 0) { int n = nb_sectors; - - switch (s->status) { + switch (status) { case BLK_BACKING_FILE: /* If we have a backing file, leave clusters unallocated that are * unallocated in the source image, so that the backing file is @@ -1607,9 +1627,13 @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, break; } - ret = blk_pwrite_compressed(s->target, - sector_num << BDRV_SECTOR_BITS, - buf, n << BDRV_SECTOR_BITS); + iov.iov_base = buf; + iov.iov_len = n << BDRV_SECTOR_BITS; + qemu_iovec_init_external(&qiov, &iov, 1); + + ret = blk_co_pwritev(s->target, sector_num << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, &qiov, + BDRV_REQ_WRITE_COMPRESSED); if (ret < 0) { return ret; } @@ -1622,8 +1646,12 @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, if (!s->min_sparse || is_allocated_sectors_min(buf, n, &n, s->min_sparse)) { - ret = blk_pwrite(s->target, sector_num << BDRV_SECTOR_BITS, - buf, n << BDRV_SECTOR_BITS, 0); + iov.iov_base = buf; + iov.iov_len = n << BDRV_SECTOR_BITS; + qemu_iovec_init_external(&qiov, &iov, 1); + + ret = blk_co_pwritev(s->target, sector_num << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, &qiov, 0); if (ret < 0) { return ret; } @@ -1635,8 +1663,9 @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, if (s->has_zero_init) { break; } - ret = blk_pwrite_zeroes(s->target, sector_num << BDRV_SECTOR_BITS, - n << BDRV_SECTOR_BITS, 0); + ret = blk_co_pwrite_zeroes(s->target, + sector_num << BDRV_SECTOR_BITS, + n << BDRV_SECTOR_BITS, 0); if (ret < 0) { return ret; } @@ -1651,12 +1680,117 @@ static int convert_write(ImgConvertState *s, int64_t sector_num, int nb_sectors, return 0; } -static int convert_do_copy(ImgConvertState *s) +static void convert_co_do_copy(void *opaque) { + ImgConvertState *s = opaque; uint8_t *buf = NULL; - int64_t sector_num, allocated_done; - int ret; - int n; + int ret, i; + int index = -1; + + for (i = 0; i < s->num_coroutines; i++) { + if (s->co[i] == qemu_coroutine_self()) { + index = i; + break; + } + } + assert(index >= 0); + + s->running_coroutines++; + buf = blk_blockalign(s->target, s->buf_sectors * BDRV_SECTOR_SIZE); + + while (1) { + int n; + int64_t sector_num; + enum ImgConvertBlockStatus status; + + qemu_co_mutex_lock(&s->lock); + if (s->ret != -EINPROGRESS || s->sector_num >= s->total_sectors) { + qemu_co_mutex_unlock(&s->lock); + goto out; + } + n = convert_iteration_sectors(s, s->sector_num); + if (n < 0) { + qemu_co_mutex_unlock(&s->lock); + s->ret = n; + goto out; + } + /* safe current sector and allocation status to local variables */ + sector_num = s->sector_num; + status = s->status; + if (!s->min_sparse && s->status == BLK_ZERO) { + n = MIN(n, s->buf_sectors); + } + /* increment global sector counter so that other coroutines can + * already continue reading beyond this request */ + s->sector_num += n; + qemu_co_mutex_unlock(&s->lock); + + if (status == BLK_DATA || (!s->min_sparse && s->status == BLK_ZERO)) { + s->allocated_done += n; + qemu_progress_print(100.0 * s->allocated_done / + s->allocated_sectors, 0); + } + + if (status == BLK_DATA) { + ret = convert_co_read(s, sector_num, n, buf); + if (ret < 0) { + error_report("error while reading sector %" PRId64 + ": %s", sector_num, strerror(-ret)); + s->ret = ret; + goto out; + } + } else if (!s->min_sparse && s->status == BLK_ZERO) { + status = BLK_DATA; + memset(buf, 0x00, n * BDRV_SECTOR_SIZE); + } + + if (s->wr_in_order) { + /* keep writes in order */ + while (s->wr_offs != sector_num) { + if (s->ret != -EINPROGRESS) { + goto out; + } + s->wait_sector_num[index] = sector_num; + qemu_coroutine_yield(); + } + s->wait_sector_num[index] = -1; + } + + ret = convert_co_write(s, sector_num, n, buf, status); + if (ret < 0) { + error_report("error while writing sector %" PRId64 + ": %s", sector_num, strerror(-ret)); + s->ret = ret; + goto out; + } + + if (s->wr_in_order) { + /* reenter the coroutine that might have waited + * for this write to complete */ + s->wr_offs = sector_num + n; + for (i = 0; i < s->num_coroutines; i++) { + if (s->co[i] && s->wait_sector_num[i] == s->wr_offs) { + qemu_coroutine_enter(s->co[i]); + break; + } + } + } + } + +out: + qemu_vfree(buf); + s->co[index] = NULL; + s->running_coroutines--; + if (!s->running_coroutines && s->ret == -EINPROGRESS) { + /* the convert job finished successfully */ + s->ret = 0; + } +} + +static int convert_do_copy(ImgConvertState *s) +{ + int ret, i, n; + int64_t sector_num = 0; /* Check whether we have zero initialisation or can get it efficiently */ s->has_zero_init = s->min_sparse && !s->target_has_backing @@ -1677,21 +1811,15 @@ static int convert_do_copy(ImgConvertState *s) if (s->compressed) { if (s->cluster_sectors <= 0 || s->cluster_sectors > s->buf_sectors) { error_report("invalid cluster size"); - ret = -EINVAL; - goto fail; + return -EINVAL; } s->buf_sectors = s->cluster_sectors; } - buf = blk_blockalign(s->target, s->buf_sectors * BDRV_SECTOR_SIZE); - /* Calculate allocated sectors for progress */ - s->allocated_sectors = 0; - sector_num = 0; while (sector_num < s->total_sectors) { n = convert_iteration_sectors(s, sector_num); if (n < 0) { - ret = n; - goto fail; + return n; } if (s->status == BLK_DATA || (!s->min_sparse && s->status == BLK_ZERO)) { @@ -1704,58 +1832,28 @@ static int convert_do_copy(ImgConvertState *s) s->src_cur = 0; s->src_cur_offset = 0; s->sector_next_status = 0; + s->ret = -EINPROGRESS; - sector_num = 0; - allocated_done = 0; - - while (sector_num < s->total_sectors) { - n = convert_iteration_sectors(s, sector_num); - if (n < 0) { - ret = n; - goto fail; - } - if (s->status == BLK_DATA || (!s->min_sparse && s->status == BLK_ZERO)) - { - allocated_done += n; - qemu_progress_print(100.0 * allocated_done / s->allocated_sectors, - 0); - } - - if (s->status == BLK_DATA) { - ret = convert_read(s, sector_num, n, buf); - if (ret < 0) { - error_report("error while reading sector %" PRId64 - ": %s", sector_num, strerror(-ret)); - goto fail; - } - } else if (!s->min_sparse && s->status == BLK_ZERO) { - n = MIN(n, s->buf_sectors); - memset(buf, 0, n * BDRV_SECTOR_SIZE); - s->status = BLK_DATA; - } - - ret = convert_write(s, sector_num, n, buf); - if (ret < 0) { - error_report("error while writing sector %" PRId64 - ": %s", sector_num, strerror(-ret)); - goto fail; - } + qemu_co_mutex_init(&s->lock); + for (i = 0; i < s->num_coroutines; i++) { + s->co[i] = qemu_coroutine_create(convert_co_do_copy, s); + s->wait_sector_num[i] = -1; + qemu_coroutine_enter(s->co[i]); + } - sector_num += n; + while (s->ret == -EINPROGRESS) { + main_loop_wait(false); } - if (s->compressed) { + if (s->compressed && !s->ret) { /* signal EOF to align */ ret = blk_pwrite_compressed(s->target, 0, NULL, 0); if (ret < 0) { - goto fail; + return ret; } } - ret = 0; -fail: - qemu_vfree(buf); - return ret; + return s->ret; } static int img_convert(int argc, char **argv) @@ -1783,6 +1881,8 @@ static int img_convert(int argc, char **argv) QemuOpts *sn_opts = NULL; ImgConvertState state; bool image_opts = false; + bool wr_in_order = true; + int num_coroutines = 8; fmt = NULL; out_fmt = "raw"; @@ -1798,7 +1898,7 @@ static int img_convert(int argc, char **argv) {"image-opts", no_argument, 0, OPTION_IMAGE_OPTS}, {0, 0, 0, 0} }; - c = getopt_long(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qn", + c = getopt_long(argc, argv, "hf:O:B:ce6o:s:l:S:pt:T:qnm:W", long_options, NULL); if (c == -1) { break; @@ -1890,6 +1990,18 @@ static int img_convert(int argc, char **argv) case 'n': skip_create = 1; break; + case 'm': + num_coroutines = atoi(optarg); + if (num_coroutines > MAX_COROUTINES) { + error_report("Maximum allowed number of coroutines is %d", + MAX_COROUTINES); + ret = -1; + goto fail_getopt; + } + break; + case 'W': + wr_in_order = false; + break; case OPTION_OBJECT: opts = qemu_opts_parse_noisily(&qemu_object_opts, optarg, true); @@ -2149,6 +2261,8 @@ static int img_convert(int argc, char **argv) .min_sparse = min_sparse, .cluster_sectors = cluster_sectors, .buf_sectors = bufsectors, + .wr_in_order = wr_in_order, + .num_coroutines = num_coroutines, }; ret = convert_do_copy(&state);

[RFC,V4] qemu-img: make convert async

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