Commit 82c41671 authored by Björn Töpel's avatar Björn Töpel Committed by Alexei Starovoitov
Browse files

xdp: Simplify xdp_return_{frame, frame_rx_napi, buff} 



The xdp_return_{frame,frame_rx_napi,buff} function are never used,
except in xdp_convert_zc_to_xdp_frame(), by the MEM_TYPE_XSK_BUFF_POOL
memory type.

To simplify and reduce code, change so that
xdp_convert_zc_to_xdp_frame() calls xsk_buff_free() directly since the
type is know, and remove MEM_TYPE_XSK_BUFF_POOL from the switch
statement in __xdp_return() function.

Suggested-by: default avatarMaxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: default avatarBjörn Töpel <bjorn.topel@intel.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200520192103.355233-14-bjorn.topel@gmail.com
parent 0807892e

net/core/xdp.c

+9 −12
Original line number Diff line number Diff line
@@ -335,10 +335,11 @@ EXPORT_SYMBOL_GPL(xdp_rxq_info_reg_mem_model); 
 * scenarios (e.g. queue full), it is possible to return the xdp_frame

 * while still leveraging this protection.  The @napi_direct boolean

 * is used for those calls sites.  Thus, allowing for faster recycling

 * of xdp_frames/pages in those cases.

 * of xdp_frames/pages in those cases. This path is never used by the

 * MEM_TYPE_XSK_BUFF_POOL memory type, so it's explicitly not part of

 * the switch-statement.

 */

static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct,

			 struct xdp_buff *xdp)

static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct)

{

	struct xdp_mem_allocator *xa;

	struct page *page;
@@ -360,33 +361,29 @@ static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct, 
		page = virt_to_page(data); /* Assumes order0 page*/

		put_page(page);

		break;

	case MEM_TYPE_XSK_BUFF_POOL:

		/* NB! Only valid from an xdp_buff! */

		xsk_buff_free(xdp);

		break;

	default:

		/* Not possible, checked in xdp_rxq_info_reg_mem_model() */

		WARN(1, "Incorrect XDP memory type (%d) usage", mem->type);

		break;

	}

}



void xdp_return_frame(struct xdp_frame *xdpf)

{

	__xdp_return(xdpf->data, &xdpf->mem, false, NULL);

	__xdp_return(xdpf->data, &xdpf->mem, false);

}

EXPORT_SYMBOL_GPL(xdp_return_frame);



void xdp_return_frame_rx_napi(struct xdp_frame *xdpf)

{

	__xdp_return(xdpf->data, &xdpf->mem, true, NULL);

	__xdp_return(xdpf->data, &xdpf->mem, true);

}

EXPORT_SYMBOL_GPL(xdp_return_frame_rx_napi);



void xdp_return_buff(struct xdp_buff *xdp)

{

	__xdp_return(xdp->data, &xdp->rxq->mem, true, xdp);

	__xdp_return(xdp->data, &xdp->rxq->mem, true);

}

EXPORT_SYMBOL_GPL(xdp_return_buff);



/* Only called for MEM_TYPE_PAGE_POOL see xdp.h */

void __xdp_release_frame(void *data, struct xdp_mem_info *mem)
@@ -467,7 +464,7 @@ struct xdp_frame *xdp_convert_zc_to_xdp_frame(struct xdp_buff *xdp) 
	xdpf->metasize = metasize;

	xdpf->mem.type = MEM_TYPE_PAGE_ORDER0;



	xdp_return_buff(xdp);

	xsk_buff_free(xdp);

	return xdpf;

}

EXPORT_SYMBOL_GPL(xdp_convert_zc_to_xdp_frame);

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