Commit 5a04099b authored by Jim Harris's avatar Jim Harris
Browse files

reduce: save compressed data size in chunk map 



Upcoming patches will try to compress the data before
writing it to backing I/O units, and we'll need to save
the exact number of compressed bytes.

For now, since we're not actually compressing data yet,
just save the uncompressed data size to this field.  There
will be cases when we cannot realize any compression
savings and will just store the uncompressed data, so
handling this now is one less path we'll need to add later.

Signed-off-by: default avatarJim Harris <james.r.harris@intel.com>
Change-Id: I499a89590349e4816fe0fef77cc1bfabde6871bf

Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/449078


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarPaul Luse <paul.e.luse@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
parent 3c070c97

lib/reduce/reduce.c

+4 −0
Original line number Diff line number Diff line
@@ -82,6 +82,8 @@ struct spdk_reduce_pm_file { 
#define REDUCE_IO_WRITEV	2



struct spdk_reduce_chunk_map {

	uint32_t		compressed_size;

	uint32_t		reserved;

	uint64_t		io_unit_index[0];

};
@@ -958,6 +960,7 @@ _reduce_vol_write_chunk(struct spdk_reduce_vol_request *req, reduce_request_fn n 
	spdk_bit_array_set(vol->allocated_chunk_maps, req->chunk_map_index);



	req->chunk = _reduce_vol_get_chunk_map(vol, req->chunk_map_index);

	req->chunk->compressed_size = vol->params.chunk_size;



	for (i = 0; i < vol->backing_io_units_per_chunk; i++) {

		req->chunk->io_unit_index[i] = spdk_bit_array_find_first_clear(vol->allocated_backing_io_units, 0);
@@ -1043,6 +1046,7 @@ _reduce_vol_read_chunk(struct spdk_reduce_vol_request *req, reduce_request_fn ne 
	assert(req->chunk_map_index != UINT32_MAX);



	req->chunk = _reduce_vol_get_chunk_map(vol, req->chunk_map_index);

	assert(req->chunk->compressed_size == vol->params.chunk_size);

	_issue_backing_ops(req, vol, next_fn, false /* read */);

}