| Message ID | 980ad3161b9a312510c9fff76fa74e675b8f9bf3.1631007211.git.lorenzo@kernel.org (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | mvneta: introduce XDP multi-buffer support | expand |
| Context | Check | Description |
|---|---|---|
| bpf/vmtest-bpf-next | pending | VM_Test |
| bpf/vmtest-bpf-next-PR | pending | PR summary |
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | fail | Series longer than 15 patches |
| netdev/tree_selection | success | Clearly marked for bpf-next |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 6 maintainers not CCed: andrii@kernel.org kafai@fb.com yhs@fb.com hawk@kernel.org kpsingh@kernel.org songliubraving@fb.com |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | fail | Errors and warnings before: 1019 this patch: 946 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 68 lines checked |
| netdev/build_allmodconfig_warn | fail | Errors and warnings before: 676 this patch: 1084 |
| netdev/header_inline | success | Link |
(Minor changes requested below) On 07/09/2021 14.35, Lorenzo Bianconi wrote: > Introduce flags field in xdp_frame and xdp_buffer data structures > to define additional buffer features. At the moment the only > supported buffer feature is multi-buffer bit (mb). Multi-buffer bit > is used to specify if this is a linear buffer (mb = 0) or a multi-buffer > frame (mb = 1). In the latter case the driver is expected to initialize > the skb_shared_info structure at the end of the first buffer to link > together subsequent buffers belonging to the same frame. > > Acked-by: John Fastabend <john.fastabend@gmail.com> > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > --- > include/net/xdp.h | 29 +++++++++++++++++++++++++++++ > 1 file changed, 29 insertions(+) > > diff --git a/include/net/xdp.h b/include/net/xdp.h > index ad5b02dcb6f4..ed5ea784fd45 100644 > --- a/include/net/xdp.h > +++ b/include/net/xdp.h > @@ -66,6 +66,10 @@ struct xdp_txq_info { > struct net_device *dev; > }; > > +enum xdp_buff_flags { > + XDP_FLAGS_MULTI_BUFF = BIT(0), /* non-linear xdp buff */ > +}; > + > struct xdp_buff { > void *data; > void *data_end; > @@ -74,13 +78,30 @@ struct xdp_buff { > struct xdp_rxq_info *rxq; > struct xdp_txq_info *txq; > u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/ > + u16 flags; /* supported values defined in xdp_flags */ ^^^^^^^^^ Variable/enum is named "xdp_buff_flags", but comment says "xdp_flags". I think we should change flags to use u32, because xdp_buff already contain 4 byte padding. (pahole output provided as help below) > }; > > +static __always_inline bool xdp_buff_is_mb(struct xdp_buff *xdp) > +{ > + return !!(xdp->flags & XDP_FLAGS_MULTI_BUFF); > +} > + > +static __always_inline void xdp_buff_set_mb(struct xdp_buff *xdp) > +{ > + xdp->flags |= XDP_FLAGS_MULTI_BUFF; > +} > + > +static __always_inline void xdp_buff_clear_mb(struct xdp_buff *xdp) > +{ > + xdp->flags &= ~XDP_FLAGS_MULTI_BUFF; > +} > + > static __always_inline void > xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq) > { > xdp->frame_sz = frame_sz; > xdp->rxq = rxq; > + xdp->flags = 0; > } > > static __always_inline void > @@ -122,8 +143,14 @@ struct xdp_frame { > */ > struct xdp_mem_info mem; > struct net_device *dev_rx; /* used by cpumap */ > + u16 flags; /* supported values defined in xdp_flags */ ^^^^^^^^^ Variable/enum is named "xdp_buff_flags", but comment says "xdp_flags". Here (for xdp_frame) I also think we should change flags to u32, because adding this u16 cause extra padding anyhow. (pahole output provided as help below). > }; > > +static __always_inline bool xdp_frame_is_mb(struct xdp_frame *frame) > +{ > + return !!(frame->flags & XDP_FLAGS_MULTI_BUFF); > +} > + > #define XDP_BULK_QUEUE_SIZE 16 > struct xdp_frame_bulk { > int count; > @@ -180,6 +207,7 @@ void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) > xdp->data_end = frame->data + frame->len; > xdp->data_meta = frame->data - frame->metasize; > xdp->frame_sz = frame->frame_sz; > + xdp->flags = frame->flags; > } > > static inline > @@ -206,6 +234,7 @@ int xdp_update_frame_from_buff(struct xdp_buff *xdp, > xdp_frame->headroom = headroom - sizeof(*xdp_frame); > xdp_frame->metasize = metasize; > xdp_frame->frame_sz = xdp->frame_sz; > + xdp_frame->flags = xdp->flags; > > return 0; > } > Details below... no need to read any further Investigating struct xdp_frame with pahole: $ pahole -C xdp_frame net/core/xdp.o struct xdp_frame { void * data; /* 0 8 */ u16 len; /* 8 2 */ u16 headroom; /* 10 2 */ u32 metasize:8; /* 12: 0 4 */ u32 frame_sz:24; /* 12: 8 4 */ struct xdp_mem_info mem; /* 16 8 */ struct net_device * dev_rx; /* 24 8 */ /* size: 32, cachelines: 1, members: 7 */ /* last cacheline: 32 bytes */ }; pahole -C xdp_frame net/core/xdp.o struct xdp_frame { void * data; /* 0 8 */ u16 len; /* 8 2 */ u16 headroom; /* 10 2 */ u32 metasize:8; /* 12: 0 4 */ u32 frame_sz:24; /* 12: 8 4 */ struct xdp_mem_info mem; /* 16 8 */ struct net_device * dev_rx; /* 24 8 */ u16 flags; /* 32 2 */ /* size: 40, cachelines: 1, members: 8 */ /* padding: 6 */ /* last cacheline: 40 bytes */ }; $ pahole -C xdp_frame net/core/xdp.o struct xdp_frame { void * data; /* 0 8 */ u16 len; /* 8 2 */ u16 headroom; /* 10 2 */ u32 metasize:8; /* 12: 0 4 */ u32 frame_sz:24; /* 12: 8 4 */ struct xdp_mem_info mem; /* 16 8 */ struct net_device * dev_rx; /* 24 8 */ u32 flags; /* 32 4 */ /* size: 40, cachelines: 1, members: 8 */ /* padding: 4 */ /* last cacheline: 40 bytes */ }; Details for struct xdp_buff, it already contains 4 bytes padding. $ pahole -C xdp_buff net/core/xdp.o struct xdp_buff { void * data; /* 0 8 */ void * data_end; /* 8 8 */ void * data_meta; /* 16 8 */ void * data_hard_start; /* 24 8 */ struct xdp_rxq_info * rxq; /* 32 8 */ struct xdp_txq_info * txq; /* 40 8 */ u32 frame_sz; /* 48 4 */ u16 flags; /* 52 2 */ /* size: 56, cachelines: 1, members: 8 */ /* padding: 2 */ /* last cacheline: 56 bytes */ };
> (Minor changes requested below) > > On 07/09/2021 14.35, Lorenzo Bianconi wrote: > > Introduce flags field in xdp_frame and xdp_buffer data structures > > to define additional buffer features. At the moment the only > > supported buffer feature is multi-buffer bit (mb). Multi-buffer bit > > is used to specify if this is a linear buffer (mb = 0) or a multi-buffer > > frame (mb = 1). In the latter case the driver is expected to initialize > > the skb_shared_info structure at the end of the first buffer to link > > together subsequent buffers belonging to the same frame. > > > > Acked-by: John Fastabend <john.fastabend@gmail.com> > > Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org> > > --- > > include/net/xdp.h | 29 +++++++++++++++++++++++++++++ > > 1 file changed, 29 insertions(+) > > > > diff --git a/include/net/xdp.h b/include/net/xdp.h > > index ad5b02dcb6f4..ed5ea784fd45 100644 > > --- a/include/net/xdp.h > > +++ b/include/net/xdp.h > > @@ -66,6 +66,10 @@ struct xdp_txq_info { > > struct net_device *dev; > > }; > > +enum xdp_buff_flags { > > + XDP_FLAGS_MULTI_BUFF = BIT(0), /* non-linear xdp buff */ > > +}; > > + > > struct xdp_buff { > > void *data; > > void *data_end; > > @@ -74,13 +78,30 @@ struct xdp_buff { > > struct xdp_rxq_info *rxq; > > struct xdp_txq_info *txq; > > u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/ > > + u16 flags; /* supported values defined in xdp_flags */ > ^^^^^^^^^ > Variable/enum is named "xdp_buff_flags", but comment says "xdp_flags". ack, I will fix it in v14 > > I think we should change flags to use u32, because xdp_buff already contain > 4 byte padding. (pahole output provided as help below) ack, I will fix it in v14 > > > }; > > +static __always_inline bool xdp_buff_is_mb(struct xdp_buff *xdp) > > +{ > > + return !!(xdp->flags & XDP_FLAGS_MULTI_BUFF); > > +} > > + > > +static __always_inline void xdp_buff_set_mb(struct xdp_buff *xdp) > > +{ > > + xdp->flags |= XDP_FLAGS_MULTI_BUFF; > > +} > > + > > +static __always_inline void xdp_buff_clear_mb(struct xdp_buff *xdp) > > +{ > > + xdp->flags &= ~XDP_FLAGS_MULTI_BUFF; > > +} > > + > > static __always_inline void > > xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq) > > { > > xdp->frame_sz = frame_sz; > > xdp->rxq = rxq; > > + xdp->flags = 0; > > } > > static __always_inline void > > @@ -122,8 +143,14 @@ struct xdp_frame { > > */ > > struct xdp_mem_info mem; > > struct net_device *dev_rx; /* used by cpumap */ > > + u16 flags; /* supported values defined in xdp_flags */ > ^^^^^^^^^ > Variable/enum is named "xdp_buff_flags", but comment says "xdp_flags". > > Here (for xdp_frame) I also think we should change flags to u32, because > adding this u16 cause extra padding anyhow. (pahole output provided as help > below). ack, I will fix it in v14 > > > > }; > > +static __always_inline bool xdp_frame_is_mb(struct xdp_frame *frame) > > +{ > > + return !!(frame->flags & XDP_FLAGS_MULTI_BUFF); > > +} > > + > > #define XDP_BULK_QUEUE_SIZE 16 > > struct xdp_frame_bulk { > > int count; > > @@ -180,6 +207,7 @@ void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) > > xdp->data_end = frame->data + frame->len; > > xdp->data_meta = frame->data - frame->metasize; > > xdp->frame_sz = frame->frame_sz; > > + xdp->flags = frame->flags; > > } > > static inline > > @@ -206,6 +234,7 @@ int xdp_update_frame_from_buff(struct xdp_buff *xdp, > > xdp_frame->headroom = headroom - sizeof(*xdp_frame); > > xdp_frame->metasize = metasize; > > xdp_frame->frame_sz = xdp->frame_sz; > > + xdp_frame->flags = xdp->flags; > > return 0; > > } > > > > > > Details below... no need to read any further > > Investigating struct xdp_frame with pahole: > > $ pahole -C xdp_frame net/core/xdp.o > struct xdp_frame { > void * data; /* 0 8 */ > u16 len; /* 8 2 */ > u16 headroom; /* 10 2 */ > u32 metasize:8; /* 12: 0 4 */ > u32 frame_sz:24; /* 12: 8 4 */ > struct xdp_mem_info mem; /* 16 8 */ > struct net_device * dev_rx; /* 24 8 */ > > /* size: 32, cachelines: 1, members: 7 */ > /* last cacheline: 32 bytes */ > }; > > > pahole -C xdp_frame net/core/xdp.o > struct xdp_frame { > void * data; /* 0 8 */ > u16 len; /* 8 2 */ > u16 headroom; /* 10 2 */ > u32 metasize:8; /* 12: 0 4 */ > u32 frame_sz:24; /* 12: 8 4 */ > struct xdp_mem_info mem; /* 16 8 */ > struct net_device * dev_rx; /* 24 8 */ > u16 flags; /* 32 2 */ > > /* size: 40, cachelines: 1, members: 8 */ > /* padding: 6 */ > /* last cacheline: 40 bytes */ > }; > > > $ pahole -C xdp_frame net/core/xdp.o > struct xdp_frame { > void * data; /* 0 8 */ > u16 len; /* 8 2 */ > u16 headroom; /* 10 2 */ > u32 metasize:8; /* 12: 0 4 */ > u32 frame_sz:24; /* 12: 8 4 */ > struct xdp_mem_info mem; /* 16 8 */ > struct net_device * dev_rx; /* 24 8 */ > u32 flags; /* 32 4 */ > > /* size: 40, cachelines: 1, members: 8 */ > /* padding: 4 */ > /* last cacheline: 40 bytes */ > }; > > > Details for struct xdp_buff, it already contains 4 bytes padding. > > $ pahole -C xdp_buff net/core/xdp.o > struct xdp_buff { > void * data; /* 0 8 */ > void * data_end; /* 8 8 */ > void * data_meta; /* 16 8 */ > void * data_hard_start; /* 24 8 */ > struct xdp_rxq_info * rxq; /* 32 8 */ > struct xdp_txq_info * txq; /* 40 8 */ > u32 frame_sz; /* 48 4 */ > u16 flags; /* 52 2 */ > > /* size: 56, cachelines: 1, members: 8 */ > /* padding: 2 */ > /* last cacheline: 56 bytes */ > }; ack, right. Regards, Lorenzo >
diff --git a/include/net/xdp.h b/include/net/xdp.h index ad5b02dcb6f4..ed5ea784fd45 100644 --- a/include/net/xdp.h +++ b/include/net/xdp.h @@ -66,6 +66,10 @@ struct xdp_txq_info { struct net_device *dev; }; +enum xdp_buff_flags { + XDP_FLAGS_MULTI_BUFF = BIT(0), /* non-linear xdp buff */ +}; + struct xdp_buff { void *data; void *data_end; @@ -74,13 +78,30 @@ struct xdp_buff { struct xdp_rxq_info *rxq; struct xdp_txq_info *txq; u32 frame_sz; /* frame size to deduce data_hard_end/reserved tailroom*/ + u16 flags; /* supported values defined in xdp_flags */ }; +static __always_inline bool xdp_buff_is_mb(struct xdp_buff *xdp) +{ + return !!(xdp->flags & XDP_FLAGS_MULTI_BUFF); +} + +static __always_inline void xdp_buff_set_mb(struct xdp_buff *xdp) +{ + xdp->flags |= XDP_FLAGS_MULTI_BUFF; +} + +static __always_inline void xdp_buff_clear_mb(struct xdp_buff *xdp) +{ + xdp->flags &= ~XDP_FLAGS_MULTI_BUFF; +} + static __always_inline void xdp_init_buff(struct xdp_buff *xdp, u32 frame_sz, struct xdp_rxq_info *rxq) { xdp->frame_sz = frame_sz; xdp->rxq = rxq; + xdp->flags = 0; } static __always_inline void @@ -122,8 +143,14 @@ struct xdp_frame { */ struct xdp_mem_info mem; struct net_device *dev_rx; /* used by cpumap */ + u16 flags; /* supported values defined in xdp_flags */ }; +static __always_inline bool xdp_frame_is_mb(struct xdp_frame *frame) +{ + return !!(frame->flags & XDP_FLAGS_MULTI_BUFF); +} + #define XDP_BULK_QUEUE_SIZE 16 struct xdp_frame_bulk { int count; @@ -180,6 +207,7 @@ void xdp_convert_frame_to_buff(struct xdp_frame *frame, struct xdp_buff *xdp) xdp->data_end = frame->data + frame->len; xdp->data_meta = frame->data - frame->metasize; xdp->frame_sz = frame->frame_sz; + xdp->flags = frame->flags; } static inline @@ -206,6 +234,7 @@ int xdp_update_frame_from_buff(struct xdp_buff *xdp, xdp_frame->headroom = headroom - sizeof(*xdp_frame); xdp_frame->metasize = metasize; xdp_frame->frame_sz = xdp->frame_sz; + xdp_frame->flags = xdp->flags; return 0; }