Commit a755fb5f authored by paul luse's avatar paul luse Committed by Darek Stojaczyk
Browse files

lib/reduce: use global zero buffer instead of zeroing scratch buffer 



Eliminates need for memset on parts of our scratch buffer

Signed-off-by: default avatarpaul luse <paul.e.luse@intel.com>
Change-Id: I00b7213d3c15562ceeda4d7a3ac2bb7cfd41bf66
Reviewed-on: https://review.gerrithub.io/c/spdk/spdk/+/460010


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarDarek Stojaczyk <dariusz.stojaczyk@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
parent 074fa326

lib/reduce/reduce.c

+40 −5
Original line number Diff line number Diff line
@@ -163,6 +163,8 @@ struct spdk_reduce_vol { 


static void _start_readv_request(struct spdk_reduce_vol_request *req);

static void _start_writev_request(struct spdk_reduce_vol_request *req);

static uint8_t *g_zero_buf;

static int g_vol_count = 0;



/*

 * Allocate extra metadata chunks and corresponding backing io units to account for
@@ -397,6 +399,26 @@ _init_load_cleanup(struct spdk_reduce_vol *vol, struct reduce_init_load_ctx *ctx 
	}

}



static int

_alloc_zero_buff(struct spdk_reduce_vol *vol)

{

	int rc = 0;



	/* The zero buffer is shared between all volumnes and just used

	 * for reads so allocate one global instance here if not already

	 * allocated when another vol init'd or loaded.

	 */

	if (g_vol_count++ == 0) {

		g_zero_buf = spdk_zmalloc(vol->params.chunk_size,

					  64, NULL, SPDK_ENV_LCORE_ID_ANY,

					  SPDK_MALLOC_DMA);

		if (g_zero_buf == NULL) {

			rc = -ENOMEM;

		}

	}

	return rc;

}



static void

_init_write_super_cpl(void *cb_arg, int reduce_errno)

{
@@ -410,6 +432,13 @@ _init_write_super_cpl(void *cb_arg, int reduce_errno) 
		return;

	}



	rc = _alloc_zero_buff(init_ctx->vol);

	if (rc != 0) {

		init_ctx->cb_fn(init_ctx->cb_arg, NULL, rc);

		_init_load_cleanup(init_ctx->vol, init_ctx);

		return;

	}



	init_ctx->cb_fn(init_ctx->cb_arg, init_ctx->vol, reduce_errno);

	/* Only clean up the ctx - the vol has been passed to the application

	 *  for use now that initialization was successful.
@@ -693,6 +722,11 @@ _load_read_super_and_path_cpl(void *cb_arg, int reduce_errno) 
		}

	}



	rc = _alloc_zero_buff(vol);

	if (rc) {

		goto error;

	}



	load_ctx->cb_fn(load_ctx->cb_arg, vol, 0);

	/* Only clean up the ctx - the vol has been passed to the application

	 *  for use now that volume load was successful.
@@ -781,6 +815,9 @@ spdk_reduce_vol_unload(struct spdk_reduce_vol *vol, 
		return;

	}



	if (--g_vol_count == 0) {

		spdk_free(g_zero_buf);

	}

	_init_load_cleanup(vol, NULL);

	cb_fn(cb_arg, 0);

}
@@ -1398,12 +1435,11 @@ _start_writev_request(struct spdk_reduce_vol_request *req) 
	lb_per_chunk = vol->logical_blocks_per_chunk;

	req->decomp_iovcnt = 0;



	/* Note: we must zero out parts of req->decomp_buf not specified by this write operation. */

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

	chunk_offset = req->offset % lb_per_chunk;

	if (chunk_offset != 0) {

		memset(req->decomp_buf, 0, chunk_offset * lbsize);

		ttl_len += chunk_offset * lbsize;

		req->decomp_iov[0].iov_base = req->decomp_buf;

		req->decomp_iov[0].iov_base = g_zero_buf;

		req->decomp_iov[0].iov_len = ttl_len;

		req->decomp_iovcnt = 1;

	}
@@ -1419,8 +1455,7 @@ _start_writev_request(struct spdk_reduce_vol_request *req) 
	chunk_offset += req->length;

	if (chunk_offset != lb_per_chunk) {

		remainder = (lb_per_chunk - chunk_offset) * lbsize;

		memset(req->decomp_buf + ttl_len, 0, remainder);

		req->decomp_iov[req->decomp_iovcnt].iov_base = req->decomp_buf + ttl_len;

		req->decomp_iov[req->decomp_iovcnt].iov_base = g_zero_buf;

		req->decomp_iov[req->decomp_iovcnt].iov_len = remainder;

		ttl_len += req->decomp_iov[req->decomp_iovcnt].iov_len;

		req->decomp_iovcnt++;