diff mbox series

[bpf-next,01/10] xsk: improve xdp_do_redirect() error codes

Message ID 20220405110631.404427-2-maciej.fijalkowski@intel.com (mailing list archive)
State Changes Requested
Delegated to: BPF
Headers show
Series xsk: stop softirq processing on full XSK Rx queue | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR pending PR summary
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Series has a cover letter
netdev/patch_count success Link
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 2 this patch: 2
netdev/cc_maintainers warning 11 maintainers not CCed: songliubraving@fb.com davem@davemloft.net andrii@kernel.org kuba@kernel.org pabeni@redhat.com kafai@fb.com jonathan.lemon@gmail.com hawk@kernel.org yhs@fb.com john.fastabend@gmail.com kpsingh@kernel.org
netdev/build_clang success Errors and warnings before: 9 this patch: 9
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 2 this patch: 2
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 16 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Maciej Fijalkowski April 5, 2022, 11:06 a.m. UTC 
From: Björn Töpel <bjorn@kernel.org>

The error codes returned by xdp_do_redirect() when redirecting a frame
to an AF_XDP socket has not been very useful. A driver could not
distinguish between different errors. Prior this change the following
codes where used:

Socket not bound or incorrect queue/netdev: EINVAL
XDP frame/AF_XDP buffer size mismatch: ENOSPC
Could not allocate buffer (copy mode): ENOSPC
AF_XDP Rx buffer full: ENOSPC

After this change:

Socket not bound or incorrect queue/netdev: EINVAL
XDP frame/AF_XDP buffer size mismatch: ENOSPC
Could not allocate buffer (copy mode): ENOMEM
AF_XDP Rx buffer full: ENOBUFS

An AF_XDP zero-copy driver can now potentially determine if the
failure was due to a full Rx buffer, and if so stop processing more
frames, yielding to the userland AF_XDP application.

Signed-off-by: Björn Töpel <bjorn@kernel.org>
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
---
 net/xdp/xsk.c       | 2 +-
 net/xdp/xsk_queue.h | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

Comments

Jesper Dangaard Brouer April 5, 2022, 12:18 p.m. UTC | #1 
On 05/04/2022 13.06, Maciej Fijalkowski wrote:
> From: Björn Töpel<bjorn@kernel.org>
> 
> The error codes returned by xdp_do_redirect() when redirecting a frame
> to an AF_XDP socket has not been very useful. A driver could not
> distinguish between different errors. Prior this change the following
> codes where used:
> 
> Socket not bound or incorrect queue/netdev: EINVAL
> XDP frame/AF_XDP buffer size mismatch: ENOSPC
> Could not allocate buffer (copy mode): ENOSPC
> AF_XDP Rx buffer full: ENOSPC
> 
> After this change:
> 
> Socket not bound or incorrect queue/netdev: EINVAL
> XDP frame/AF_XDP buffer size mismatch: ENOSPC
> Could not allocate buffer (copy mode): ENOMEM
> AF_XDP Rx buffer full: ENOBUFS
> 
> An AF_XDP zero-copy driver can now potentially determine if the
> failure was due to a full Rx buffer, and if so stop processing more
> frames, yielding to the userland AF_XDP application.
> 
> Signed-off-by: Björn Töpel<bjorn@kernel.org>
> Signed-off-by: Maciej Fijalkowski<maciej.fijalkowski@intel.com>

Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>

Thanks for picking this work up again! :-)
--Jesper
diff mbox series

Patch

diff --git a/net/xdp/xsk.c b/net/xdp/xsk.c
index 2c34caee0fd1..f75e121073e7 100644
--- a/net/xdp/xsk.c
+++ b/net/xdp/xsk.c
@@ -184,7 +184,7 @@  static int __xsk_rcv(struct xdp_sock *xs, struct xdp_buff *xdp)
 	xsk_xdp = xsk_buff_alloc(xs->pool);
 	if (!xsk_xdp) {
 		xs->rx_dropped++;
-		return -ENOSPC;
+		return -ENOMEM;
 	}
 
 	xsk_copy_xdp(xsk_xdp, xdp, len);
diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h
index 801cda5d1938..644479e65578 100644
--- a/net/xdp/xsk_queue.h
+++ b/net/xdp/xsk_queue.h
@@ -382,7 +382,7 @@  static inline int xskq_prod_reserve_desc(struct xsk_queue *q,
 	u32 idx;
 
 	if (xskq_prod_is_full(q))
-		return -ENOSPC;
+		return -ENOBUFS;
 
 	/* A, matches D */
 	idx = q->cached_prod++ & q->ring_mask;