Commit c2d44122 authored by paul luse's avatar paul luse Committed by Darek Stojaczyk
Browse files

lib/reduce: close hole in compress optimization 



If a write operation comes in and is not a read-modify-write but
we don't end up compressing the data (because of either error or
we decide the compression ratio isn't good enough) then we not
only need to copy the data to the host buffers but we need to
zero any offset and/or remainder in the decomp scratch buffer.

Change-Id: Ifb2235507826f9ef1110dd9dbaf88045d8979e7c
Signed-off-by: default avatarpaul luse <paul.e.luse@intel.com>
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/463337


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
parent bc315dea

lib/reduce/reduce.c

+23 −2
Original line number Diff line number Diff line
@@ -118,6 +118,7 @@ struct spdk_reduce_vol_request { 
	uint8_t					*comp_buf;

	struct iovec				*comp_buf_iov;

	struct iovec				*iov;

	bool					rmw;

	struct spdk_reduce_vol			*vol;

	int					type;

	int					reduce_errno;
@@ -1045,7 +1046,7 @@ _reduce_vol_write_chunk(struct spdk_reduce_vol_request *req, reduce_request_fn n 
{

	struct spdk_reduce_vol *vol = req->vol;

	uint32_t i;

	uint64_t chunk_offset;

	uint64_t chunk_offset, remainder, total_len = 0;

	uint8_t *buf;

	int j;
@@ -1067,11 +1068,29 @@ _reduce_vol_write_chunk(struct spdk_reduce_vol_request *req, reduce_request_fn n 
	/* if the chunk is uncompressed we need to copy the data from the host buffers. */

	if (req->chunk_is_compressed == false) {

		chunk_offset = req->offset % vol->logical_blocks_per_chunk;

		buf = req->decomp_buf + chunk_offset * vol->params.logical_block_size;

		buf = req->decomp_buf;

		total_len = chunk_offset * vol->params.logical_block_size;



		/* zero any offset into chunk */

		if (req->rmw == false && chunk_offset) {

			memset(buf, 0, total_len);

		}

		buf += total_len;



		/* copy the data */

		for (j = 0; j < req->iovcnt; j++) {

			memcpy(buf, req->iov[j].iov_base, req->iov[j].iov_len);

			buf += req->iov[j].iov_len;

			total_len += req->iov[j].iov_len;

		}



		/* zero any remainder */

		remainder = vol->params.chunk_size - total_len;

		total_len += remainder;

		if (req->rmw == false && remainder) {

			memset(buf, 0, remainder);

		}

		assert(total_len == vol->params.chunk_size);

	}



	for (i = 0; i < req->num_io_units; i++) {
@@ -1454,6 +1473,7 @@ _start_writev_request(struct spdk_reduce_vol_request *req) 
			/* Read old chunk, then overwrite with data from this write

			 *  operation.

			 */

			req->rmw = true;

			_reduce_vol_read_chunk(req, _write_read_done);

			return;

		}
@@ -1461,6 +1481,7 @@ _start_writev_request(struct spdk_reduce_vol_request *req) 


	lbsize = vol->params.logical_block_size;

	req->decomp_iovcnt = 0;

	req->rmw = false;



	/* Note: point to our zero buf for offset into the chunk. */

	chunk_offset = req->offset % vol->logical_blocks_per_chunk;