Re: [Qemu-devel] [PATCH v2 00/13] Dirty bitmap changes for migration/persistence work

[Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>]

An idea/question.

What about make some const dirty bitmap finctions really const?

bdrv_dirty_bitmap_name(BdrvDirtyBitmap *bitmap)   -> 
bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap)
bdrv_dirty_bitmap_size(BdrvDirtyBitmap *bitmap)     -> 
bdrv_dirty_bitmap_size(const BdrvDirtyBitmap *bitmap)

etc..

I don't know, may be it is not Qemu style or there are some other 
restrictions, but in common case strict definitions are better.. In my 
persistent series I've included a fix for this "[PATCH 01/17] block: fix 
bdrv_dirty_bitmap_granularity()", necessary for my other functions with 
const BdrvDirtyBitmap *bitmap.

I can add such fixes into my series (but these series are better place, 
I think), or, if it is bad for Qemu, I'll remove all such const's from 
my series.


On 20.01.2016 09:11, Fam Zheng wrote:
> v2: Various changes addressing John's and Vladimir's comments:
>
>      [02/13] typedefs: Add BdrvDirtyBitmap
>              Skip HBitmapIter because we'll hide it soon. [John]
>              
>      [03/13] block: Move block dirty bitmap code to separate files
>      [04/13] block: Remove unused typedef of BlockDriverDirtyHandler
>      [05/13] block: Hide HBitmap in block dirty bitmap interface
>              Add assert in bdrv_dirty_bitmap_truncate(). [John]
>              Add John's rev-by.
>
>      [06/13] HBitmap: Introduce "meta" bitmap to track bit changes
>              Caller of hbitmap_create_meta() frees it with hbitmap_free_meta().
>              [John, Vladimir]
>
>      [07/13] tests: Add test code for meta bitmap
>              Add John's rev-by.
>
>      [08/13] block: Support meta dirty bitmap
>              Release the meta dirty bitmap in bdrv_release_dirty_bitmap().
>
>      [09/13] block: Add two dirty bitmap getters
>      [10/13] block: Assert that bdrv_release_dirty_bitmap succeeded
>              Add John's rev-by.
>
>      [11/13] hbitmap: serialization
>              Fix comment for hbitmap_serialization_granularity() and
>              hbitmap_deserialize_part(). [John]
>              Document @finish in hbitmap_deserialize_zeroes more clearly.
>              Fixed granularity in hbitmap_serialization_granularity().
>              [Vladimir]
>              Tweak the assertion in serialization_chunk. [Vladimir]
>              cpu_to_leXXs -> leXX_to_cpus in hbitmap_deserialize_part.
>              [Vladimir]
>              Fix typo in serialization_chunk() comments. [John]
>
>      [12/13] block: BdrvDirtyBitmap serialization interface
>      [13/13] tests: Add test code for hbitmap serialization
>
>
> Two major features are added to block dirty bitmap (and underlying HBitmap) in
> this series: meta bitmap and serialization, together with all other supportive
> patches.
>
> Both operations are common in dirty bitmap migration and persistence: they need
> to find whether and which part of the dirty bitmap in question has changed with
> meta dirty bitmap, and they need to write it to the target with serialization.
>
>
> Fam Zheng (11):
>    backup: Use Bitmap to replace "s->bitmap"
>    typedefs: Add BdrvDirtyBitmap
>    block: Move block dirty bitmap code to separate files
>    block: Remove unused typedef of BlockDriverDirtyHandler
>    block: Hide HBitmap in block dirty bitmap interface
>    HBitmap: Introduce "meta" bitmap to track bit changes
>    tests: Add test code for meta bitmap
>    block: Support meta dirty bitmap
>    block: Add two dirty bitmap getters
>    block: Assert that bdrv_release_dirty_bitmap succeeded
>    tests: Add test code for hbitmap serialization
>
> Vladimir Sementsov-Ogievskiy (2):
>    hbitmap: serialization
>    block: BdrvDirtyBitmap serialization interface
>
>   block.c                      | 339 -----------------------------
>   block/Makefile.objs          |   2 +-
>   block/backup.c               |  25 ++-
>   block/dirty-bitmap.c         | 492 +++++++++++++++++++++++++++++++++++++++++++
>   block/mirror.c               |  14 +-
>   include/block/block.h        |  40 +---
>   include/block/dirty-bitmap.h |  71 +++++++
>   include/qemu/hbitmap.h       |  95 +++++++++
>   include/qemu/typedefs.h      |   2 +
>   tests/test-hbitmap.c         | 255 ++++++++++++++++++++++
>   util/hbitmap.c               | 201 ++++++++++++++++--
>   11 files changed, 1126 insertions(+), 410 deletions(-)
>   create mode 100644 block/dirty-bitmap.c
>   create mode 100644 include/block/dirty-bitmap.h
>


-- 
Best regards,
Vladimir
* now, @virtuozzo.com instead of @parallels.com. Sorry for this inconvenience.