Am 12.04.2014 um 20:57 hat Max Reitz geschrieben:
> Implement progress output for the commit command by querying the
> progress of the block job.
>
> Signed-off-by: Max Reitz <mre...@redhat.com>
> ---
> qemu-img-cmds.hx | 4 ++--
> qemu-img.c | 44 ++++++++++++++++++++++++++++++++++++++++++--
> qemu-img.texi | 2 +-
> 3 files changed, 45 insertions(+), 5 deletions(-)
>
> diff --git a/qemu-img-cmds.hx b/qemu-img-cmds.hx
> index d029609..8bc55cd 100644
> --- a/qemu-img-cmds.hx
> +++ b/qemu-img-cmds.hx
> @@ -22,9 +22,9 @@ STEXI
> ETEXI
>
> DEF("commit", img_commit,
> - "commit [-q] [-f fmt] [-t cache] filename")
> + "commit [-q] [-f fmt] [-t cache] [-p] filename")
> STEXI
> -@item commit [-q] [-f @var{fmt}] [-t @var{cache}] @var{filename}
> +@item commit [-q] [-f @var{fmt}] [-t @var{cache}] [-p] @var{filename}
> ETEXI
>
> DEF("compare", img_compare,
> diff --git a/qemu-img.c b/qemu-img.c
> index 9fe6384..50d7519 100644
> --- a/qemu-img.c
> +++ b/qemu-img.c
> @@ -686,6 +686,9 @@ fail:
> struct CommonBlockJobCBInfo {
> Error **errp;
> bool done;
> + /* If the blockjob works on several sectors at once, this field has to
> + * contain that granularity in bytes */
> + uint64_t granularity;
> };
>
> static void common_block_job_cb(void *opaque, int ret)
> @@ -702,12 +705,34 @@ static void common_block_job_cb(void *opaque, int ret)
> static void run_block_job(BlockJob *job, struct CommonBlockJobCBInfo *cbi)
> {
> BlockJobInfo *info;
> + uint64_t mod_offset = 0;
>
> do {
> qemu_aio_wait();
>
> info = block_job_query(job);
>
> + if (info->offset) {
> + if (!mod_offset) {
> + /* Some block jobs (at least "commit") will only work on a
> + * subset of the image file and therefore basically skip many
> + * sectors at the start (processing them apparently
> + * instantaneously). These sectors should be ignored when
> + * calculating the progress.
> + * If the blockjob processes several sectors at once, the
> first
> + * progress report is likely to come after one such sector
> group
> + * (whose size is cbi->granularity), therefore subtract it
> from
> + * the current offset in order to obtain a more probable
> + * starting offset. */
> + mod_offset = info->offset > cbi->granularity
> + ? info->offset - cbi->granularity
> + : 0;
granularity != buf_size. And you still can't distinguish whether the
first chunk was skipped or copied.
In the v2 review I suggested changing mirror_run() to update
s->common.len. There you wouldn't have to make any assumptions, but
would know exactly where the bitmap initialisation is done. And it would
improve traditional block job progress output, too.
Am I missing anything that makes this approach harder than it seems?
Kevin
