diff options
author | Jakub Kicinski <kuba@kernel.org> | 2022-09-29 04:51:27 +0300 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2022-09-29 04:51:28 +0300 |
commit | 578b054684e6ad46f6089b726c05054fc5e3cd74 (patch) | |
tree | b14a20279c36ca9fac082210cf5419e057075337 | |
parent | 929a6cdfaeac9de6a1004eb18999e1439527cfb4 (diff) | |
parent | e7d2b510165fff6bedc9cca88c071ad846850c74 (diff) | |
download | linux-578b054684e6ad46f6089b726c05054fc5e3cd74.tar.xz |
Merge branch 'shrink-struct-ubuf_info'
Pavel Begunkov says:
====================
shrink struct ubuf_info
struct ubuf_info is large but not all fields are needed for all
cases. We have limited space in io_uring for it and large ubuf_info
prevents some struct embedding, even though we use only a subset
of the fields. It's also not very clean trying to use this typeless
extra space.
Shrink struct ubuf_info to only necessary fields used in generic paths,
namely ->callback, ->refcnt and ->flags, which take only 16 bytes. And
make MSG_ZEROCOPY and some other users to embed it into a larger struct
ubuf_info_msgzc mimicking the former ubuf_info.
Note, xen/vhost may also have some cleaning on top by creating
new structs containing ubuf_info but with proper types.
====================
Link: https://lore.kernel.org/r/cover.1663892211.git.asml.silence@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-rw-r--r-- | drivers/net/xen-netback/common.h | 2 | ||||
-rw-r--r-- | drivers/net/xen-netback/interface.c | 4 | ||||
-rw-r--r-- | drivers/net/xen-netback/netback.c | 7 | ||||
-rw-r--r-- | drivers/vhost/net.c | 15 | ||||
-rw-r--r-- | include/linux/skbuff.h | 11 | ||||
-rw-r--r-- | net/core/skbuff.c | 38 | ||||
-rw-r--r-- | net/ipv4/ip_output.c | 2 | ||||
-rw-r--r-- | net/ipv4/tcp.c | 2 | ||||
-rw-r--r-- | net/ipv6/ip6_output.c | 2 |
9 files changed, 48 insertions, 35 deletions
diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h index 8174d7b2966c..1545cbee77a4 100644 --- a/drivers/net/xen-netback/common.h +++ b/drivers/net/xen-netback/common.h @@ -62,7 +62,7 @@ struct pending_tx_info { * ubuf_to_vif is a helper which finds the struct xenvif from a pointer * to this field. */ - struct ubuf_info callback_struct; + struct ubuf_info_msgzc callback_struct; }; #define XEN_NETIF_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, XEN_PAGE_SIZE) diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index fb32ae82d9b0..e579ecd40b74 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -591,8 +591,8 @@ int xenvif_init_queue(struct xenvif_queue *queue) } for (i = 0; i < MAX_PENDING_REQS; i++) { - queue->pending_tx_info[i].callback_struct = (struct ubuf_info) - { .callback = xenvif_zerocopy_callback, + queue->pending_tx_info[i].callback_struct = (struct ubuf_info_msgzc) + { { .callback = xenvif_zerocopy_callback }, { { .ctx = NULL, .desc = i } } }; queue->grant_tx_handle[i] = NETBACK_INVALID_HANDLE; diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c index a256695fc89e..3d2081bbbc86 100644 --- a/drivers/net/xen-netback/netback.c +++ b/drivers/net/xen-netback/netback.c @@ -133,7 +133,7 @@ static inline unsigned long idx_to_kaddr(struct xenvif_queue *queue, /* Find the containing VIF's structure from a pointer in pending_tx_info array */ -static inline struct xenvif_queue *ubuf_to_queue(const struct ubuf_info *ubuf) +static inline struct xenvif_queue *ubuf_to_queue(const struct ubuf_info_msgzc *ubuf) { u16 pending_idx = ubuf->desc; struct pending_tx_info *temp = @@ -1228,11 +1228,12 @@ static int xenvif_tx_submit(struct xenvif_queue *queue) return work_done; } -void xenvif_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *ubuf, +void xenvif_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *ubuf_base, bool zerocopy_success) { unsigned long flags; pending_ring_idx_t index; + struct ubuf_info_msgzc *ubuf = uarg_to_msgzc(ubuf_base); struct xenvif_queue *queue = ubuf_to_queue(ubuf); /* This is the only place where we grab this lock, to protect callbacks @@ -1241,7 +1242,7 @@ void xenvif_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *ubuf, spin_lock_irqsave(&queue->callback_lock, flags); do { u16 pending_idx = ubuf->desc; - ubuf = (struct ubuf_info *) ubuf->ctx; + ubuf = (struct ubuf_info_msgzc *) ubuf->ctx; BUG_ON(queue->dealloc_prod - queue->dealloc_cons >= MAX_PENDING_REQS); index = pending_index(queue->dealloc_prod); diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 68e4ecd1cc0e..d7a04d573988 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -118,7 +118,7 @@ struct vhost_net_virtqueue { /* Number of XDP frames batched */ int batched_xdp; /* an array of userspace buffers info */ - struct ubuf_info *ubuf_info; + struct ubuf_info_msgzc *ubuf_info; /* Reference counting for outstanding ubufs. * Protected by vq mutex. Writers must also take device mutex. */ struct vhost_net_ubuf_ref *ubufs; @@ -382,8 +382,9 @@ static void vhost_zerocopy_signal_used(struct vhost_net *net, } static void vhost_zerocopy_callback(struct sk_buff *skb, - struct ubuf_info *ubuf, bool success) + struct ubuf_info *ubuf_base, bool success) { + struct ubuf_info_msgzc *ubuf = uarg_to_msgzc(ubuf_base); struct vhost_net_ubuf_ref *ubufs = ubuf->ctx; struct vhost_virtqueue *vq = ubufs->vq; int cnt; @@ -871,7 +872,7 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) size_t len, total_len = 0; int err; struct vhost_net_ubuf_ref *ubufs; - struct ubuf_info *ubuf; + struct ubuf_info_msgzc *ubuf; bool zcopy_used; int sent_pkts = 0; @@ -907,14 +908,14 @@ static void handle_tx_zerocopy(struct vhost_net *net, struct socket *sock) ubuf = nvq->ubuf_info + nvq->upend_idx; vq->heads[nvq->upend_idx].id = cpu_to_vhost32(vq, head); vq->heads[nvq->upend_idx].len = VHOST_DMA_IN_PROGRESS; - ubuf->callback = vhost_zerocopy_callback; ubuf->ctx = nvq->ubufs; ubuf->desc = nvq->upend_idx; - ubuf->flags = SKBFL_ZEROCOPY_FRAG; - refcount_set(&ubuf->refcnt, 1); + ubuf->ubuf.callback = vhost_zerocopy_callback; + ubuf->ubuf.flags = SKBFL_ZEROCOPY_FRAG; + refcount_set(&ubuf->ubuf.refcnt, 1); msg.msg_control = &ctl; ctl.type = TUN_MSG_UBUF; - ctl.ptr = ubuf; + ctl.ptr = &ubuf->ubuf; msg.msg_controllen = sizeof(ctl); ubufs = nvq->ubufs; atomic_inc(&ubufs->refcount); diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index f15d5b62539b..920eb6413fee 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -533,6 +533,13 @@ enum { struct ubuf_info { void (*callback)(struct sk_buff *, struct ubuf_info *, bool zerocopy_success); + refcount_t refcnt; + u8 flags; +}; + +struct ubuf_info_msgzc { + struct ubuf_info ubuf; + union { struct { unsigned long desc; @@ -545,8 +552,6 @@ struct ubuf_info { u32 bytelen; }; }; - refcount_t refcnt; - u8 flags; struct mmpin { struct user_struct *user; @@ -555,6 +560,8 @@ struct ubuf_info { }; #define skb_uarg(SKB) ((struct ubuf_info *)(skb_shinfo(SKB)->destructor_arg)) +#define uarg_to_msgzc(ubuf_ptr) container_of((ubuf_ptr), struct ubuf_info_msgzc, \ + ubuf) int mm_account_pinned_pages(struct mmpin *mmp, size_t size); void mm_unaccount_pinned_pages(struct mmpin *mmp); diff --git a/net/core/skbuff.c b/net/core/skbuff.c index f1b8b20fc20b..bbcfb1c7f59e 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -1188,7 +1188,7 @@ EXPORT_SYMBOL_GPL(mm_unaccount_pinned_pages); static struct ubuf_info *msg_zerocopy_alloc(struct sock *sk, size_t size) { - struct ubuf_info *uarg; + struct ubuf_info_msgzc *uarg; struct sk_buff *skb; WARN_ON_ONCE(!in_task()); @@ -1206,19 +1206,19 @@ static struct ubuf_info *msg_zerocopy_alloc(struct sock *sk, size_t size) return NULL; } - uarg->callback = msg_zerocopy_callback; + uarg->ubuf.callback = msg_zerocopy_callback; uarg->id = ((u32)atomic_inc_return(&sk->sk_zckey)) - 1; uarg->len = 1; uarg->bytelen = size; uarg->zerocopy = 1; - uarg->flags = SKBFL_ZEROCOPY_FRAG | SKBFL_DONT_ORPHAN; - refcount_set(&uarg->refcnt, 1); + uarg->ubuf.flags = SKBFL_ZEROCOPY_FRAG | SKBFL_DONT_ORPHAN; + refcount_set(&uarg->ubuf.refcnt, 1); sock_hold(sk); - return uarg; + return &uarg->ubuf; } -static inline struct sk_buff *skb_from_uarg(struct ubuf_info *uarg) +static inline struct sk_buff *skb_from_uarg(struct ubuf_info_msgzc *uarg) { return container_of((void *)uarg, struct sk_buff, cb); } @@ -1227,6 +1227,7 @@ struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size, struct ubuf_info *uarg) { if (uarg) { + struct ubuf_info_msgzc *uarg_zc; const u32 byte_limit = 1 << 19; /* limit to a few TSO */ u32 bytelen, next; @@ -1242,8 +1243,9 @@ struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size, return NULL; } - bytelen = uarg->bytelen + size; - if (uarg->len == USHRT_MAX - 1 || bytelen > byte_limit) { + uarg_zc = uarg_to_msgzc(uarg); + bytelen = uarg_zc->bytelen + size; + if (uarg_zc->len == USHRT_MAX - 1 || bytelen > byte_limit) { /* TCP can create new skb to attach new uarg */ if (sk->sk_type == SOCK_STREAM) goto new_alloc; @@ -1251,11 +1253,11 @@ struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size, } next = (u32)atomic_read(&sk->sk_zckey); - if ((u32)(uarg->id + uarg->len) == next) { - if (mm_account_pinned_pages(&uarg->mmp, size)) + if ((u32)(uarg_zc->id + uarg_zc->len) == next) { + if (mm_account_pinned_pages(&uarg_zc->mmp, size)) return NULL; - uarg->len++; - uarg->bytelen = bytelen; + uarg_zc->len++; + uarg_zc->bytelen = bytelen; atomic_set(&sk->sk_zckey, ++next); /* no extra ref when appending to datagram (MSG_MORE) */ @@ -1291,7 +1293,7 @@ static bool skb_zerocopy_notify_extend(struct sk_buff *skb, u32 lo, u16 len) return true; } -static void __msg_zerocopy_callback(struct ubuf_info *uarg) +static void __msg_zerocopy_callback(struct ubuf_info_msgzc *uarg) { struct sk_buff *tail, *skb = skb_from_uarg(uarg); struct sock_exterr_skb *serr; @@ -1344,19 +1346,21 @@ release: void msg_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *uarg, bool success) { - uarg->zerocopy = uarg->zerocopy & success; + struct ubuf_info_msgzc *uarg_zc = uarg_to_msgzc(uarg); + + uarg_zc->zerocopy = uarg_zc->zerocopy & success; if (refcount_dec_and_test(&uarg->refcnt)) - __msg_zerocopy_callback(uarg); + __msg_zerocopy_callback(uarg_zc); } EXPORT_SYMBOL_GPL(msg_zerocopy_callback); void msg_zerocopy_put_abort(struct ubuf_info *uarg, bool have_uref) { - struct sock *sk = skb_from_uarg(uarg)->sk; + struct sock *sk = skb_from_uarg(uarg_to_msgzc(uarg))->sk; atomic_dec(&sk->sk_zckey); - uarg->len--; + uarg_to_msgzc(uarg)->len--; if (have_uref) msg_zerocopy_callback(NULL, uarg, true); diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c index 8201cd423ff9..1ae83ad629b2 100644 --- a/net/ipv4/ip_output.c +++ b/net/ipv4/ip_output.c @@ -1043,7 +1043,7 @@ static int __ip_append_data(struct sock *sk, paged = true; zc = true; } else { - uarg->zerocopy = 0; + uarg_to_msgzc(uarg)->zerocopy = 0; skb_zcopy_set(skb, uarg, &extra_uref); } } diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 5702ca9b952d..a109a4cb1e47 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1239,7 +1239,7 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) } zc = sk->sk_route_caps & NETIF_F_SG; if (!zc) - uarg->zerocopy = 0; + uarg_to_msgzc(uarg)->zerocopy = 0; } } diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index a60176e913a8..e19507614f64 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -1567,7 +1567,7 @@ emsgsize: paged = true; zc = true; } else { - uarg->zerocopy = 0; + uarg_to_msgzc(uarg)->zerocopy = 0; skb_zcopy_set(skb, uarg, &extra_uref); } } |