qapi: backup: add perf.use-copy-range parameter

Experiments show, that copy_range is not always making things faster.
So, to make experimentation simpler, let's add a parameter. Some more
perf parameters will be added soon, so here is a new struct.

For now, add new backup qmp parameter with x- prefix for the following
reasons:

 - We are going to add more performance parameters, some will be
   related to the whole block-copy process, some only to background
   copying in backup (ignored for copy-before-write operations).
 - On the other hand, we are going to use block-copy interface in other
   block jobs, which will need performance options as well.. And it
   should be the same structure or at least somehow related.

So, there are too much unclean things about how the interface and now
we need the new options mostly for testing. Let's keep them
experimental for a while.

In do_backup_common() new x-perf parameter handled in a way to
make further options addition simpler.

We add use-copy-range with default=true, and we'll change the default
in further patch, after moving backup to use block-copy.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20210116214705.822267-2-vsementsov@virtuozzo.com>
[mreitz: s/5\.2/6.0/]
Signed-off-by: Max Reitz <mreitz@redhat.com>
This commit is contained in:
Vladimir Sementsov-Ogievskiy 2021-01-17 00:46:43 +03:00 committed by Max Reitz
parent f4be822519
commit 86c6a3b690
9 changed files with 41 additions and 6 deletions

View file

@ -22,7 +22,7 @@ typedef void (*ProgressBytesCallbackFunc)(int64_t bytes, void *opaque);
typedef struct BlockCopyState BlockCopyState;
BlockCopyState *block_copy_state_new(BdrvChild *source, BdrvChild *target,
int64_t cluster_size,
int64_t cluster_size, bool use_copy_range,
BdrvRequestFlags write_flags,
Error **errp);

View file

@ -1266,6 +1266,8 @@ void mirror_start(const char *job_id, BlockDriverState *bs,
* @sync_mode: What parts of the disk image should be copied to the destination.
* @sync_bitmap: The dirty bitmap if sync_mode is 'bitmap' or 'incremental'
* @bitmap_mode: The bitmap synchronization policy to use.
* @perf: Performance options. All actual fields assumed to be present,
* all ".has_*" fields are ignored.
* @on_source_error: The action to take upon error reading from the source.
* @on_target_error: The action to take upon error writing to the target.
* @creation_flags: Flags that control the behavior of the Job lifetime.
@ -1284,6 +1286,7 @@ BlockJob *backup_job_create(const char *job_id, BlockDriverState *bs,
BitmapSyncMode bitmap_mode,
bool compress,
const char *filter_node_name,
BackupPerf *perf,
BlockdevOnError on_source_error,
BlockdevOnError on_target_error,
int creation_flags,