| Message ID | 1360944010-15336-7-git-send-email-wei.liu2@citrix.com |
|---|---|
| State | Not Applicable, archived |
| Delegated to: | David Miller |
| Headers | show |
On 2013-2-16 0:00, Wei Liu wrote: > Signed-off-by: Wei Liu<wei.liu2@citrix.com> > --- > drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- > 1 file changed, 174 insertions(+), 72 deletions(-) > > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > index 8bd75a1..de73a71 100644 > --- a/drivers/net/xen-netfront.c > +++ b/drivers/net/xen-netfront.c > @@ -67,9 +67,19 @@ struct netfront_cb { > > #define GRANT_INVALID_REF 0 > > -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) > -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) > -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) > +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER > +#define XENNET_MAX_RING_PAGES (1U<< XENNET_MAX_RING_PAGE_ORDER) > + > + > +#define NET_TX_RING_SIZE(_nr_pages) \ > + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) > +#define NET_RX_RING_SIZE(_nr_pages) \ > + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) > + > +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) > +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) > + > +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) Not using multi-page ring here? In xennet_create_dev, gnttab_alloc_grant_references allocates TX_MAX_TARGET number of grant reference for tx. In xennet_release_tx_bufs, NET_TX_RING_SIZE(np->tx_ring_pages) numbers of grants are processed. And NET_RX_RING_SIZE(np->tx_ring_pages) is totally different from TX_MAX_TARGET if np->rx_ring_pages is not 1. Although skb_entry_is_link helps to not release invalid grants, lots of null loop seems unnecessary. I think TX_MAX_TARGET should be changed into some variableconnected with np->tx_ring_pages. Or you intended to use one page ring here? > > struct netfront_stats { > u64 rx_packets; > @@ -80,6 +90,11 @@ struct netfront_stats { > }; > > struct netfront_info { > + /* Statistics */ > + struct netfront_stats __percpu *stats; > + > + unsigned long rx_gso_checksum_fixup; > + > struct list_head list; > struct net_device *netdev; > > @@ -90,7 +105,9 @@ struct netfront_info { > > spinlock_t tx_lock; > struct xen_netif_tx_front_ring tx; > - int tx_ring_ref; > + int tx_ring_ref[XENNET_MAX_RING_PAGES]; > + unsigned int tx_ring_page_order; > + unsigned int tx_ring_pages; > > /* > * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries > @@ -104,36 +121,33 @@ struct netfront_info { > union skb_entry { > struct sk_buff *skb; > unsigned long link; > - } tx_skbs[NET_TX_RING_SIZE]; > + } tx_skbs[XENNET_MAX_TX_RING_SIZE]; > grant_ref_t gref_tx_head; > - grant_ref_t grant_tx_ref[NET_TX_RING_SIZE]; > + grant_ref_t grant_tx_ref[XENNET_MAX_TX_RING_SIZE]; > unsigned tx_skb_freelist; > > spinlock_t rx_lock ____cacheline_aligned_in_smp; > struct xen_netif_rx_front_ring rx; > - int rx_ring_ref; > + int rx_ring_ref[XENNET_MAX_RING_PAGES]; > + unsigned int rx_ring_page_order; > + unsigned int rx_ring_pages; > > /* Receive-ring batched refills. */ > #define RX_MIN_TARGET 8 > #define RX_DFL_MIN_TARGET 64 > -#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256) > +#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE(1), 256) Not using multi-page ring here? (See comments of tx side above) Thanks Annie > unsigned rx_min_target, rx_max_target, rx_target; > struct sk_buff_head rx_batch; > > struct timer_list rx_refill_timer; > > - struct sk_buff *rx_skbs[NET_RX_RING_SIZE]; > + struct sk_buff *rx_skbs[XENNET_MAX_RX_RING_SIZE]; > grant_ref_t gref_rx_head; > - grant_ref_t grant_rx_ref[NET_RX_RING_SIZE]; > - > - unsigned long rx_pfn_array[NET_RX_RING_SIZE]; > - struct multicall_entry rx_mcl[NET_RX_RING_SIZE+1]; > - struct mmu_update rx_mmu[NET_RX_RING_SIZE]; > - > - /* Statistics */ > - struct netfront_stats __percpu *stats; > + grant_ref_t grant_rx_ref[XENNET_MAX_RX_RING_SIZE]; > > - unsigned long rx_gso_checksum_fixup; > + unsigned long rx_pfn_array[XENNET_MAX_RX_RING_SIZE]; > + struct multicall_entry rx_mcl[XENNET_MAX_RX_RING_SIZE+1]; > + struct mmu_update rx_mmu[XENNET_MAX_RX_RING_SIZE]; > }; > > struct netfront_rx_info { > @@ -171,15 +185,15 @@ static unsigned short get_id_from_freelist(unsigned *head, > return id; > } > > -static int xennet_rxidx(RING_IDX idx) > +static int xennet_rxidx(RING_IDX idx, struct netfront_info *info) > { > - return idx& (NET_RX_RING_SIZE - 1); > + return idx& (NET_RX_RING_SIZE(info->rx_ring_pages) - 1); > } > > static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np, > RING_IDX ri) > { > - int i = xennet_rxidx(ri); > + int i = xennet_rxidx(ri, np); > struct sk_buff *skb = np->rx_skbs[i]; > np->rx_skbs[i] = NULL; > return skb; > @@ -188,7 +202,7 @@ static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np, > static grant_ref_t xennet_get_rx_ref(struct netfront_info *np, > RING_IDX ri) > { > - int i = xennet_rxidx(ri); > + int i = xennet_rxidx(ri, np); > grant_ref_t ref = np->grant_rx_ref[i]; > np->grant_rx_ref[i] = GRANT_INVALID_REF; > return ref; > @@ -301,7 +315,7 @@ no_skb: > > skb->dev = dev; > > - id = xennet_rxidx(req_prod + i); > + id = xennet_rxidx(req_prod + i, np); > > BUG_ON(np->rx_skbs[id]); > np->rx_skbs[id] = skb; > @@ -653,7 +667,7 @@ static int xennet_close(struct net_device *dev) > static void xennet_move_rx_slot(struct netfront_info *np, struct sk_buff *skb, > grant_ref_t ref) > { > - int new = xennet_rxidx(np->rx.req_prod_pvt); > + int new = xennet_rxidx(np->rx.req_prod_pvt, np); > > BUG_ON(np->rx_skbs[new]); > np->rx_skbs[new] = skb; > @@ -1109,7 +1123,7 @@ static void xennet_release_tx_bufs(struct netfront_info *np) > struct sk_buff *skb; > int i; > > - for (i = 0; i< NET_TX_RING_SIZE; i++) { > + for (i = 0; i< NET_TX_RING_SIZE(np->tx_ring_pages); i++) { > /* Skip over entries which are actually freelist references */ > if (skb_entry_is_link(&np->tx_skbs[i])) > continue; > @@ -1143,7 +1157,7 @@ static void xennet_release_rx_bufs(struct netfront_info *np) > > spin_lock_bh(&np->rx_lock); > > - for (id = 0; id< NET_RX_RING_SIZE; id++) { > + for (id = 0; id< NET_RX_RING_SIZE(np->rx_ring_pages); id++) { > ref = np->grant_rx_ref[id]; > if (ref == GRANT_INVALID_REF) { > unused++; > @@ -1324,13 +1338,13 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev) > > /* Initialise tx_skbs as a free chain containing every entry. */ > np->tx_skb_freelist = 0; > - for (i = 0; i< NET_TX_RING_SIZE; i++) { > + for (i = 0; i< XENNET_MAX_TX_RING_SIZE; i++) { > skb_entry_set_link(&np->tx_skbs[i], i+1); > np->grant_tx_ref[i] = GRANT_INVALID_REF; > } > > /* Clear out rx_skbs */ > - for (i = 0; i< NET_RX_RING_SIZE; i++) { > + for (i = 0; i< XENNET_MAX_RX_RING_SIZE; i++) { > np->rx_skbs[i] = NULL; > np->grant_rx_ref[i] = GRANT_INVALID_REF; > } > @@ -1428,13 +1442,6 @@ static int netfront_probe(struct xenbus_device *dev, > return err; > } > > -static void xennet_end_access(int ref, void *page) > -{ > - /* This frees the page as a side-effect */ > - if (ref != GRANT_INVALID_REF) > - gnttab_end_foreign_access(ref, 0, (unsigned long)page); > -} > - > static void xennet_disconnect_backend(struct netfront_info *info) > { > /* Stop old i/f to prevent errors whilst we rebuild the state. */ > @@ -1448,12 +1455,12 @@ static void xennet_disconnect_backend(struct netfront_info *info) > unbind_from_irqhandler(info->netdev->irq, info->netdev); > info->evtchn = info->netdev->irq = 0; > > - /* End access and free the pages */ > - xennet_end_access(info->tx_ring_ref, info->tx.sring); > - xennet_end_access(info->rx_ring_ref, info->rx.sring); > + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring); > + free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order); > + > + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring); > + free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order); > > - info->tx_ring_ref = GRANT_INVALID_REF; > - info->rx_ring_ref = GRANT_INVALID_REF; > info->tx.sring = NULL; > info->rx.sring = NULL; > } > @@ -1501,11 +1508,14 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) > struct xen_netif_tx_sring *txs; > struct xen_netif_rx_sring *rxs; > int err; > - int grefs[1]; > struct net_device *netdev = info->netdev; > + unsigned int max_tx_ring_page_order, max_rx_ring_page_order; > + int i; > > - info->tx_ring_ref = GRANT_INVALID_REF; > - info->rx_ring_ref = GRANT_INVALID_REF; > + for (i = 0; i< XENNET_MAX_RING_PAGES; i++) { > + info->tx_ring_ref[i] = GRANT_INVALID_REF; > + info->rx_ring_ref[i] = GRANT_INVALID_REF; > + } > info->rx.sring = NULL; > info->tx.sring = NULL; > netdev->irq = 0; > @@ -1516,50 +1526,100 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) > goto fail; > } > > - txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); > + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, > + "max-tx-ring-page-order", "%u", > + &max_tx_ring_page_order); > + if (err< 0) { > + info->tx_ring_page_order = 0; > + dev_info(&dev->dev, "single tx ring\n"); > + } else { > + if (max_tx_ring_page_order> XENNET_MAX_RING_PAGE_ORDER) { > + dev_info(&dev->dev, > + "backend ring page order %d too large, clamp to %d\n", > + max_tx_ring_page_order, > + XENNET_MAX_RING_PAGE_ORDER); > + max_tx_ring_page_order = XENNET_MAX_RING_PAGE_ORDER; > + } > + info->tx_ring_page_order = max_tx_ring_page_order; > + dev_info(&dev->dev, "multi-page tx ring, order = %d\n", > + info->tx_ring_page_order); > + } > + info->tx_ring_pages = (1U<< info->tx_ring_page_order); > + > + txs = (struct xen_netif_tx_sring *) > + __get_free_pages(__GFP_ZERO | GFP_NOIO | __GFP_HIGH, > + info->tx_ring_page_order); > if (!txs) { > err = -ENOMEM; > xenbus_dev_fatal(dev, err, "allocating tx ring page"); > goto fail; > } > SHARED_RING_INIT(txs); > - FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE); > + FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE * info->tx_ring_pages); > + > + err = xenbus_grant_ring(dev, txs, info->tx_ring_pages, > + info->tx_ring_ref); > + if (err< 0) > + goto grant_tx_ring_fail; > > - err = xenbus_grant_ring(dev, txs, 1, grefs); > + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, > + "max-rx-ring-page-order", "%u", > + &max_rx_ring_page_order); > if (err< 0) { > - free_page((unsigned long)txs); > - goto fail; > + info->rx_ring_page_order = 0; > + dev_info(&dev->dev, "single rx ring\n"); > + } else { > + if (max_rx_ring_page_order> XENNET_MAX_RING_PAGE_ORDER) { > + dev_info(&dev->dev, > + "backend ring page order %d too large, clamp to %d\n", > + max_rx_ring_page_order, > + XENNET_MAX_RING_PAGE_ORDER); > + max_rx_ring_page_order = XENNET_MAX_RING_PAGE_ORDER; > + } > + info->rx_ring_page_order = max_rx_ring_page_order; > + dev_info(&dev->dev, "multi-page rx ring, order = %d\n", > + info->rx_ring_page_order); > } > + info->rx_ring_pages = (1U<< info->rx_ring_page_order); > > - info->tx_ring_ref = grefs[0]; > - rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); > + rxs = (struct xen_netif_rx_sring *) > + __get_free_pages(__GFP_ZERO | GFP_NOIO | __GFP_HIGH, > + info->rx_ring_page_order); > if (!rxs) { > err = -ENOMEM; > xenbus_dev_fatal(dev, err, "allocating rx ring page"); > - goto fail; > + goto alloc_rx_ring_fail; > } > SHARED_RING_INIT(rxs); > - FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE); > + FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE * info->rx_ring_pages); > > - err = xenbus_grant_ring(dev, rxs, 1, grefs); > - if (err< 0) { > - free_page((unsigned long)rxs); > - goto fail; > - } > - info->rx_ring_ref = grefs[0]; > + err = xenbus_grant_ring(dev, rxs, info->rx_ring_pages, > + info->rx_ring_ref); > + if (err< 0) > + goto grant_rx_ring_fail; > > err = xenbus_alloc_evtchn(dev,&info->evtchn); > if (err) > - goto fail; > + goto alloc_evtchn_fail; > > err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, > 0, netdev->name, netdev); > if (err< 0) > - goto fail; > + goto bind_fail; > netdev->irq = err; > return 0; > > - fail: > +bind_fail: > + xenbus_free_evtchn(dev, info->evtchn); > +alloc_evtchn_fail: > + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring); > +grant_rx_ring_fail: > + free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order); > +alloc_rx_ring_fail: > + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring); > +grant_tx_ring_fail: > + free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order); > +fail: > return err; > } > > @@ -1570,6 +1630,7 @@ static int talk_to_netback(struct xenbus_device *dev, > const char *message; > struct xenbus_transaction xbt; > int err; > + int i; > > /* Create shared ring, alloc event channel. */ > err = setup_netfront(dev, info); > @@ -1583,18 +1644,58 @@ again: > goto destroy_ring; > } > > - err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u", > - info->tx_ring_ref); > - if (err) { > - message = "writing tx ring-ref"; > - goto abort_transaction; > + if (info->tx_ring_page_order == 0) { > + err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u", > + info->tx_ring_ref[0]); > + if (err) { > + message = "writing tx ring-ref"; > + goto abort_transaction; > + } > + } else { > + err = xenbus_printf(xbt, dev->nodename, "tx-ring-order", "%u", > + info->tx_ring_page_order); > + if (err) { > + message = "writing tx-ring-order"; > + goto abort_transaction; > + } > + for (i = 0; i< info->tx_ring_pages; i++) { > + char name[sizeof("tx-ring-ref")+3]; > + snprintf(name, sizeof(name), "tx-ring-ref%u", i); > + err = xenbus_printf(xbt, dev->nodename, name, "%u", > + info->tx_ring_ref[i]); > + if (err) { > + message = "writing tx ring-ref"; > + goto abort_transaction; > + } > + } > } > - err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u", > - info->rx_ring_ref); > - if (err) { > - message = "writing rx ring-ref"; > - goto abort_transaction; > + > + if (info->rx_ring_page_order == 0) { > + err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u", > + info->rx_ring_ref[0]); > + if (err) { > + message = "writing rx ring-ref"; > + goto abort_transaction; > + } > + } else { > + err = xenbus_printf(xbt, dev->nodename, "rx-ring-order", "%u", > + info->rx_ring_page_order); > + if (err) { > + message = "writing rx-ring-order"; > + goto abort_transaction; > + } > + for (i = 0; i< info->rx_ring_pages; i++) { > + char name[sizeof("rx-ring-ref")+3]; > + snprintf(name, sizeof(name), "rx-ring-ref%u", i); > + err = xenbus_printf(xbt, dev->nodename, name, "%u", > + info->rx_ring_ref[i]); > + if (err) { > + message = "writing rx ring-ref"; > + goto abort_transaction; > + } > + } > } > + > err = xenbus_printf(xbt, dev->nodename, > "event-channel", "%u", info->evtchn); > if (err) { > @@ -1681,7 +1782,8 @@ static int xennet_connect(struct net_device *dev) > xennet_release_tx_bufs(np); > > /* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */ > - for (requeue_idx = 0, i = 0; i< NET_RX_RING_SIZE; i++) { > + for (requeue_idx = 0, i = 0; i< NET_RX_RING_SIZE(np->rx_ring_pages); > + i++) { > skb_frag_t *frag; > const struct page *page; > if (!np->rx_skbs[i]) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Tue, 2013-02-26 at 06:52 +0000, ANNIE LI wrote: > > On 2013-2-16 0:00, Wei Liu wrote: > > Signed-off-by: Wei Liu<wei.liu2@citrix.com> > > --- > > drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- > > 1 file changed, 174 insertions(+), 72 deletions(-) > > > > diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > > index 8bd75a1..de73a71 100644 > > --- a/drivers/net/xen-netfront.c > > +++ b/drivers/net/xen-netfront.c > > @@ -67,9 +67,19 @@ struct netfront_cb { > > > > #define GRANT_INVALID_REF 0 > > > > -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) > > -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) > > -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) > > +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER > > +#define XENNET_MAX_RING_PAGES (1U<< XENNET_MAX_RING_PAGE_ORDER) > > + > > + > > +#define NET_TX_RING_SIZE(_nr_pages) \ > > + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) > > +#define NET_RX_RING_SIZE(_nr_pages) \ > > + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) > > + > > +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) > > +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) > > + > > +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) > > Not using multi-page ring here? > In xennet_create_dev, gnttab_alloc_grant_references allocates > TX_MAX_TARGET number of grant reference for tx. In > xennet_release_tx_bufs, NET_TX_RING_SIZE(np->tx_ring_pages) numbers of > grants are processed. And NET_RX_RING_SIZE(np->tx_ring_pages) is totally > different from TX_MAX_TARGET if np->rx_ring_pages is not 1. Although > skb_entry_is_link helps to not release invalid grants, lots of null loop > seems unnecessary. I think TX_MAX_TARGET should be changed into some > variableconnected with np->tx_ring_pages. Or you intended to use one > page ring here? > Looking back my history, this limitation was introduced because if we have a multi-page backend and single page frontend, the backend skb processing could overlap. I agree with you that this limit should be variable, but as we still use M:N model, the safe option is to cap this limit to 1 page. Another option is to check validity of skbs before processing them. I will look into that as well. The same reason applies to the RX ring as well. Wei. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2013-2-26 20:35, Wei Liu wrote: > On Tue, 2013-02-26 at 06:52 +0000, ANNIE LI wrote: >> On 2013-2-16 0:00, Wei Liu wrote: >>> Signed-off-by: Wei Liu<wei.liu2@citrix.com> >>> --- >>> drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- >>> 1 file changed, 174 insertions(+), 72 deletions(-) >>> >>> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c >>> index 8bd75a1..de73a71 100644 >>> --- a/drivers/net/xen-netfront.c >>> +++ b/drivers/net/xen-netfront.c >>> @@ -67,9 +67,19 @@ struct netfront_cb { >>> >>> #define GRANT_INVALID_REF 0 >>> >>> -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) >>> -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) >>> -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) >>> +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER >>> +#define XENNET_MAX_RING_PAGES (1U<< XENNET_MAX_RING_PAGE_ORDER) >>> + >>> + >>> +#define NET_TX_RING_SIZE(_nr_pages) \ >>> + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) >>> +#define NET_RX_RING_SIZE(_nr_pages) \ >>> + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) >>> + >>> +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) >>> +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) >>> + >>> +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) >> Not using multi-page ring here? >> In xennet_create_dev, gnttab_alloc_grant_references allocates >> TX_MAX_TARGET number of grant reference for tx. In >> xennet_release_tx_bufs, NET_TX_RING_SIZE(np->tx_ring_pages) numbers of >> grants are processed. And NET_RX_RING_SIZE(np->tx_ring_pages) is totally >> different from TX_MAX_TARGET if np->rx_ring_pages is not 1. Although >> skb_entry_is_link helps to not release invalid grants, lots of null loop >> seems unnecessary. I think TX_MAX_TARGET should be changed into some >> variableconnected with np->tx_ring_pages. Or you intended to use one >> page ring here? >> > Looking back my history, this limitation was introduced because if we > have a multi-page backend and single page frontend, the backend skb > processing could overlap. I did not see the overlap you mentioned here in netback. Although netback supports multi-page, netback->vif still uses single page if the frontend only supports single page. Netfront and netback negotiate this through xenstore in your 5/8 patch. The requests and response should not have any overlap between netback and netfront. Am I missing something? > > I agree with you that this limit should be variable, but as we still use > M:N model, the safe option is to cap this limit to 1 page. Yes, M:N model is still used here. But the share ring should be same for netback->vif and netfront. Thanks Annie > > Another option is to check validity of skbs before processing them. I > will look into that as well. > > The same reason applies to the RX ring as well. > > > Wei. > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, 2013-02-27 at 07:39 +0000, ANNIE LI wrote: > > On 2013-2-26 20:35, Wei Liu wrote: > > On Tue, 2013-02-26 at 06:52 +0000, ANNIE LI wrote: > >> On 2013-2-16 0:00, Wei Liu wrote: > >>> Signed-off-by: Wei Liu<wei.liu2@citrix.com> > >>> --- > >>> drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- > >>> 1 file changed, 174 insertions(+), 72 deletions(-) > >>> > >>> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > >>> index 8bd75a1..de73a71 100644 > >>> --- a/drivers/net/xen-netfront.c > >>> +++ b/drivers/net/xen-netfront.c > >>> @@ -67,9 +67,19 @@ struct netfront_cb { > >>> > >>> #define GRANT_INVALID_REF 0 > >>> > >>> -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) > >>> -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) > >>> -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) > >>> +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER > >>> +#define XENNET_MAX_RING_PAGES (1U<< XENNET_MAX_RING_PAGE_ORDER) > >>> + > >>> + > >>> +#define NET_TX_RING_SIZE(_nr_pages) \ > >>> + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) > >>> +#define NET_RX_RING_SIZE(_nr_pages) \ > >>> + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) > >>> + > >>> +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) > >>> +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) > >>> + > >>> +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) > >> Not using multi-page ring here? > >> In xennet_create_dev, gnttab_alloc_grant_references allocates > >> TX_MAX_TARGET number of grant reference for tx. In > >> xennet_release_tx_bufs, NET_TX_RING_SIZE(np->tx_ring_pages) numbers of > >> grants are processed. And NET_RX_RING_SIZE(np->tx_ring_pages) is totally > >> different from TX_MAX_TARGET if np->rx_ring_pages is not 1. Although > >> skb_entry_is_link helps to not release invalid grants, lots of null loop > >> seems unnecessary. I think TX_MAX_TARGET should be changed into some > >> variableconnected with np->tx_ring_pages. Or you intended to use one > >> page ring here? > >> > > Looking back my history, this limitation was introduced because if we > > have a multi-page backend and single page frontend, the backend skb > > processing could overlap. > > I did not see the overlap you mentioned here in netback. Although > netback supports multi-page, netback->vif still uses single page if the > frontend only supports single page. Netfront and netback negotiate this > through xenstore in your 5/8 patch. The requests and response should not > have any overlap between netback and netfront. Am I missing something? > I tried to dig up mail archive just now and realized that the bug report was in private mail exchange with Konrad. I don't really remember the details now since it is more than one year old, but you can find trace in Konrad's tree, CS 5b4c3dd5b255. All I can remember is that this bug was triggered by mixed old/new frontend/backend. I think this cap can be removed if we make all buffers in netfront dynamically allocated. Wei. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2013-2-27 23:49, Wei Liu wrote: > On Wed, 2013-02-27 at 07:39 +0000, ANNIE LI wrote: >> On 2013-2-26 20:35, Wei Liu wrote: >>> On Tue, 2013-02-26 at 06:52 +0000, ANNIE LI wrote: >>>> On 2013-2-16 0:00, Wei Liu wrote: >>>>> Signed-off-by: Wei Liu<wei.liu2@citrix.com> >>>>> --- >>>>> drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- >>>>> 1 file changed, 174 insertions(+), 72 deletions(-) >>>>> >>>>> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c >>>>> index 8bd75a1..de73a71 100644 >>>>> --- a/drivers/net/xen-netfront.c >>>>> +++ b/drivers/net/xen-netfront.c >>>>> @@ -67,9 +67,19 @@ struct netfront_cb { >>>>> >>>>> #define GRANT_INVALID_REF 0 >>>>> >>>>> -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) >>>>> -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) >>>>> -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) >>>>> +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER >>>>> +#define XENNET_MAX_RING_PAGES (1U<< XENNET_MAX_RING_PAGE_ORDER) >>>>> + >>>>> + >>>>> +#define NET_TX_RING_SIZE(_nr_pages) \ >>>>> + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) >>>>> +#define NET_RX_RING_SIZE(_nr_pages) \ >>>>> + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) >>>>> + >>>>> +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) >>>>> +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) >>>>> + >>>>> +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) >>>> Not using multi-page ring here? >>>> In xennet_create_dev, gnttab_alloc_grant_references allocates >>>> TX_MAX_TARGET number of grant reference for tx. In >>>> xennet_release_tx_bufs, NET_TX_RING_SIZE(np->tx_ring_pages) numbers of >>>> grants are processed. And NET_RX_RING_SIZE(np->tx_ring_pages) is totally >>>> different from TX_MAX_TARGET if np->rx_ring_pages is not 1. Although >>>> skb_entry_is_link helps to not release invalid grants, lots of null loop >>>> seems unnecessary. I think TX_MAX_TARGET should be changed into some >>>> variableconnected with np->tx_ring_pages. Or you intended to use one >>>> page ring here? >>>> >>> Looking back my history, this limitation was introduced because if we >>> have a multi-page backend and single page frontend, the backend skb >>> processing could overlap. >> I did not see the overlap you mentioned here in netback. Although >> netback supports multi-page, netback->vif still uses single page if the >> frontend only supports single page. Netfront and netback negotiate this >> through xenstore in your 5/8 patch. The requests and response should not >> have any overlap between netback and netfront. Am I missing something? >> > I tried to dig up mail archive just now and realized that the bug report > was in private mail exchange with Konrad. > > I don't really remember the details now since it is more than one year > old, but you can find trace in Konrad's tree, CS 5b4c3dd5b255. All I can > remember is that this bug was triggered by mixed old/new > frontend/backend. I checked the code in Konrad's tree and am thinking this overlap issue you mentioned existing in original netback(without multi-ring) and newer netfront. Original netback does not support multi-ring, and your newer netfront before this bug fix used "#define TX_MAX_TARGET XENNET_MAX_TX_RING_SIZE" directly. So that would cause overlap when netfront allocating rx skbs. "#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256)" limits the netfront to single ring, it fixed the overlap issue, but not enough. > > I think this cap can be removed if we make all buffers in netfront > dynamically allocated. Yes, making TX_MAX_TARGET dynamically would fix this issue. Thanks Annie > > > Wei. > > -- > To unsubscribe from this list: send the line "unsubscribe netdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Feb 28, 2013 at 05:19:43AM +0000, ANNIE LI wrote: > > > On 2013-2-27 23:49, Wei Liu wrote: > > On Wed, 2013-02-27 at 07:39 +0000, ANNIE LI wrote: > >> On 2013-2-26 20:35, Wei Liu wrote: > >>> On Tue, 2013-02-26 at 06:52 +0000, ANNIE LI wrote: > >>>> On 2013-2-16 0:00, Wei Liu wrote: > >>>>> Signed-off-by: Wei Liu<wei.liu2@citrix.com> > >>>>> --- > >>>>> drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- > >>>>> 1 file changed, 174 insertions(+), 72 deletions(-) > >>>>> > >>>>> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c > >>>>> index 8bd75a1..de73a71 100644 > >>>>> --- a/drivers/net/xen-netfront.c > >>>>> +++ b/drivers/net/xen-netfront.c > >>>>> @@ -67,9 +67,19 @@ struct netfront_cb { > >>>>> > >>>>> #define GRANT_INVALID_REF 0 > >>>>> > >>>>> -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) > >>>>> -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) > >>>>> -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) > >>>>> +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER > >>>>> +#define XENNET_MAX_RING_PAGES (1U<< XENNET_MAX_RING_PAGE_ORDER) > >>>>> + > >>>>> + > >>>>> +#define NET_TX_RING_SIZE(_nr_pages) \ > >>>>> + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) > >>>>> +#define NET_RX_RING_SIZE(_nr_pages) \ > >>>>> + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) > >>>>> + > >>>>> +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) > >>>>> +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) > >>>>> + > >>>>> +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) > >>>> Not using multi-page ring here? > >>>> In xennet_create_dev, gnttab_alloc_grant_references allocates > >>>> TX_MAX_TARGET number of grant reference for tx. In > >>>> xennet_release_tx_bufs, NET_TX_RING_SIZE(np->tx_ring_pages) numbers of > >>>> grants are processed. And NET_RX_RING_SIZE(np->tx_ring_pages) is totally > >>>> different from TX_MAX_TARGET if np->rx_ring_pages is not 1. Although > >>>> skb_entry_is_link helps to not release invalid grants, lots of null loop > >>>> seems unnecessary. I think TX_MAX_TARGET should be changed into some > >>>> variableconnected with np->tx_ring_pages. Or you intended to use one > >>>> page ring here? > >>>> > >>> Looking back my history, this limitation was introduced because if we > >>> have a multi-page backend and single page frontend, the backend skb > >>> processing could overlap. > >> I did not see the overlap you mentioned here in netback. Although > >> netback supports multi-page, netback->vif still uses single page if the > >> frontend only supports single page. Netfront and netback negotiate this > >> through xenstore in your 5/8 patch. The requests and response should not > >> have any overlap between netback and netfront. Am I missing something? > >> > > I tried to dig up mail archive just now and realized that the bug report > > was in private mail exchange with Konrad. > > > > I don't really remember the details now since it is more than one year > > old, but you can find trace in Konrad's tree, CS 5b4c3dd5b255. All I can > > remember is that this bug was triggered by mixed old/new > > frontend/backend. > > I checked the code in Konrad's tree and am thinking this overlap issue > you mentioned existing in original netback(without multi-ring) and newer > netfront. Original netback does not support multi-ring, and your newer > netfront before this bug fix used "#define TX_MAX_TARGET > XENNET_MAX_TX_RING_SIZE" directly. So that would cause overlap when > netfront allocating rx skbs. > "#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256)" limits the > netfront to single ring, it fixed the overlap issue, but not enough. > Yes. I just saw a bug report from Xen-user list yesterday for the same issue in original netback (1 page ring), so the overlap issue is not introduced by multi-page ring implementation. If your team also sees that issue, do you have patch to fix that? Wei. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 2013-2-28 19:02, Wei Liu wrote: > On Thu, Feb 28, 2013 at 05:19:43AM +0000, ANNIE LI wrote: >> I checked the code in Konrad's tree and am thinking this overlap issue >> you mentioned existing in original netback(without multi-ring) and newer >> netfront. Original netback does not support multi-ring, and your newer >> netfront before this bug fix used "#define TX_MAX_TARGET >> XENNET_MAX_TX_RING_SIZE" directly. So that would cause overlap when >> netfront allocating rx skbs. >> "#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256)" limits the >> netfront to single ring, it fixed the overlap issue, but not enough. >> > Yes. I just saw a bug report from Xen-user list yesterday for the same > issue in original netback (1 page ring), so the overlap issue is not > introduced by multi-page ring implementation. If your team also sees that > issue, do you have patch to fix that? No. We thought your patch fixed it, and I did not check it further at that time. Are you sure they are same? What is the thread title in Xen-user? The overlap issue here exists in netfront when netfront allocates skb greedily. In Konrad's tree merged with your patch, netfront with "#define TX_MAX_TARGET XENNET_MAX_TX_RING_SIZE" should hit this overlap issue when it runs with single ring netback. Thanks Annie -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Feb 15, 2013 at 04:00:07PM +0000, Wei Liu wrote:
Please:
1) Explain the new PV protocol (you could just do a copy-n-paste
from what you had in the backend).
2).Also submit a patch to Xen hypervisor tree for the new XenBus
extension.
3). Explain in which scenarios this benefits the user.
4). Also provide a Documentation/ABI/stable/sysfs-bus-xen-frontend
to explain the new parameter.
> Signed-off-by: Wei Liu <wei.liu2@citrix.com>
> ---
> drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++-------------
> 1 file changed, 174 insertions(+), 72 deletions(-)
>
> diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
> index 8bd75a1..de73a71 100644
> --- a/drivers/net/xen-netfront.c
> +++ b/drivers/net/xen-netfront.c
> @@ -67,9 +67,19 @@ struct netfront_cb {
>
> #define GRANT_INVALID_REF 0
>
> -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE)
> -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE)
> -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256)
> +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER
> +#define XENNET_MAX_RING_PAGES (1U << XENNET_MAX_RING_PAGE_ORDER)
> +
> +
> +#define NET_TX_RING_SIZE(_nr_pages) \
> + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages))
> +#define NET_RX_RING_SIZE(_nr_pages) \
> + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages))
> +
> +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES)
> +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES)
> +
> +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256)
>
> struct netfront_stats {
> u64 rx_packets;
> @@ -80,6 +90,11 @@ struct netfront_stats {
> };
>
> struct netfront_info {
> + /* Statistics */
> + struct netfront_stats __percpu *stats;
> +
> + unsigned long rx_gso_checksum_fixup;
> +
> struct list_head list;
> struct net_device *netdev;
>
> @@ -90,7 +105,9 @@ struct netfront_info {
>
> spinlock_t tx_lock;
> struct xen_netif_tx_front_ring tx;
> - int tx_ring_ref;
> + int tx_ring_ref[XENNET_MAX_RING_PAGES];
> + unsigned int tx_ring_page_order;
> + unsigned int tx_ring_pages;
>
> /*
> * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries
> @@ -104,36 +121,33 @@ struct netfront_info {
> union skb_entry {
> struct sk_buff *skb;
> unsigned long link;
> - } tx_skbs[NET_TX_RING_SIZE];
> + } tx_skbs[XENNET_MAX_TX_RING_SIZE];
> grant_ref_t gref_tx_head;
> - grant_ref_t grant_tx_ref[NET_TX_RING_SIZE];
> + grant_ref_t grant_tx_ref[XENNET_MAX_TX_RING_SIZE];
> unsigned tx_skb_freelist;
>
> spinlock_t rx_lock ____cacheline_aligned_in_smp;
> struct xen_netif_rx_front_ring rx;
> - int rx_ring_ref;
> + int rx_ring_ref[XENNET_MAX_RING_PAGES];
> + unsigned int rx_ring_page_order;
> + unsigned int rx_ring_pages;
>
> /* Receive-ring batched refills. */
> #define RX_MIN_TARGET 8
> #define RX_DFL_MIN_TARGET 64
> -#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256)
> +#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE(1), 256)
> unsigned rx_min_target, rx_max_target, rx_target;
> struct sk_buff_head rx_batch;
>
> struct timer_list rx_refill_timer;
>
> - struct sk_buff *rx_skbs[NET_RX_RING_SIZE];
> + struct sk_buff *rx_skbs[XENNET_MAX_RX_RING_SIZE];
> grant_ref_t gref_rx_head;
> - grant_ref_t grant_rx_ref[NET_RX_RING_SIZE];
> -
> - unsigned long rx_pfn_array[NET_RX_RING_SIZE];
> - struct multicall_entry rx_mcl[NET_RX_RING_SIZE+1];
> - struct mmu_update rx_mmu[NET_RX_RING_SIZE];
> -
> - /* Statistics */
> - struct netfront_stats __percpu *stats;
> + grant_ref_t grant_rx_ref[XENNET_MAX_RX_RING_SIZE];
>
> - unsigned long rx_gso_checksum_fixup;
> + unsigned long rx_pfn_array[XENNET_MAX_RX_RING_SIZE];
> + struct multicall_entry rx_mcl[XENNET_MAX_RX_RING_SIZE+1];
> + struct mmu_update rx_mmu[XENNET_MAX_RX_RING_SIZE];
> };
>
> struct netfront_rx_info {
> @@ -171,15 +185,15 @@ static unsigned short get_id_from_freelist(unsigned *head,
> return id;
> }
>
> -static int xennet_rxidx(RING_IDX idx)
> +static int xennet_rxidx(RING_IDX idx, struct netfront_info *info)
> {
> - return idx & (NET_RX_RING_SIZE - 1);
> + return idx & (NET_RX_RING_SIZE(info->rx_ring_pages) - 1);
> }
>
> static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np,
> RING_IDX ri)
> {
> - int i = xennet_rxidx(ri);
> + int i = xennet_rxidx(ri, np);
> struct sk_buff *skb = np->rx_skbs[i];
> np->rx_skbs[i] = NULL;
> return skb;
> @@ -188,7 +202,7 @@ static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np,
> static grant_ref_t xennet_get_rx_ref(struct netfront_info *np,
> RING_IDX ri)
> {
> - int i = xennet_rxidx(ri);
> + int i = xennet_rxidx(ri, np);
> grant_ref_t ref = np->grant_rx_ref[i];
> np->grant_rx_ref[i] = GRANT_INVALID_REF;
> return ref;
> @@ -301,7 +315,7 @@ no_skb:
>
> skb->dev = dev;
>
> - id = xennet_rxidx(req_prod + i);
> + id = xennet_rxidx(req_prod + i, np);
>
> BUG_ON(np->rx_skbs[id]);
> np->rx_skbs[id] = skb;
> @@ -653,7 +667,7 @@ static int xennet_close(struct net_device *dev)
> static void xennet_move_rx_slot(struct netfront_info *np, struct sk_buff *skb,
> grant_ref_t ref)
> {
> - int new = xennet_rxidx(np->rx.req_prod_pvt);
> + int new = xennet_rxidx(np->rx.req_prod_pvt, np);
>
> BUG_ON(np->rx_skbs[new]);
> np->rx_skbs[new] = skb;
> @@ -1109,7 +1123,7 @@ static void xennet_release_tx_bufs(struct netfront_info *np)
> struct sk_buff *skb;
> int i;
>
> - for (i = 0; i < NET_TX_RING_SIZE; i++) {
> + for (i = 0; i < NET_TX_RING_SIZE(np->tx_ring_pages); i++) {
> /* Skip over entries which are actually freelist references */
> if (skb_entry_is_link(&np->tx_skbs[i]))
> continue;
> @@ -1143,7 +1157,7 @@ static void xennet_release_rx_bufs(struct netfront_info *np)
>
> spin_lock_bh(&np->rx_lock);
>
> - for (id = 0; id < NET_RX_RING_SIZE; id++) {
> + for (id = 0; id < NET_RX_RING_SIZE(np->rx_ring_pages); id++) {
> ref = np->grant_rx_ref[id];
> if (ref == GRANT_INVALID_REF) {
> unused++;
> @@ -1324,13 +1338,13 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev)
>
> /* Initialise tx_skbs as a free chain containing every entry. */
> np->tx_skb_freelist = 0;
> - for (i = 0; i < NET_TX_RING_SIZE; i++) {
> + for (i = 0; i < XENNET_MAX_TX_RING_SIZE; i++) {
> skb_entry_set_link(&np->tx_skbs[i], i+1);
> np->grant_tx_ref[i] = GRANT_INVALID_REF;
> }
>
> /* Clear out rx_skbs */
> - for (i = 0; i < NET_RX_RING_SIZE; i++) {
> + for (i = 0; i < XENNET_MAX_RX_RING_SIZE; i++) {
> np->rx_skbs[i] = NULL;
> np->grant_rx_ref[i] = GRANT_INVALID_REF;
> }
> @@ -1428,13 +1442,6 @@ static int netfront_probe(struct xenbus_device *dev,
> return err;
> }
>
> -static void xennet_end_access(int ref, void *page)
> -{
> - /* This frees the page as a side-effect */
> - if (ref != GRANT_INVALID_REF)
> - gnttab_end_foreign_access(ref, 0, (unsigned long)page);
> -}
> -
> static void xennet_disconnect_backend(struct netfront_info *info)
> {
> /* Stop old i/f to prevent errors whilst we rebuild the state. */
> @@ -1448,12 +1455,12 @@ static void xennet_disconnect_backend(struct netfront_info *info)
> unbind_from_irqhandler(info->netdev->irq, info->netdev);
> info->evtchn = info->netdev->irq = 0;
>
> - /* End access and free the pages */
> - xennet_end_access(info->tx_ring_ref, info->tx.sring);
> - xennet_end_access(info->rx_ring_ref, info->rx.sring);
> + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring);
> + free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order);
> +
> + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring);
> + free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order);
>
> - info->tx_ring_ref = GRANT_INVALID_REF;
> - info->rx_ring_ref = GRANT_INVALID_REF;
> info->tx.sring = NULL;
> info->rx.sring = NULL;
> }
> @@ -1501,11 +1508,14 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info)
> struct xen_netif_tx_sring *txs;
> struct xen_netif_rx_sring *rxs;
> int err;
> - int grefs[1];
> struct net_device *netdev = info->netdev;
> + unsigned int max_tx_ring_page_order, max_rx_ring_page_order;
> + int i;
>
> - info->tx_ring_ref = GRANT_INVALID_REF;
> - info->rx_ring_ref = GRANT_INVALID_REF;
> + for (i = 0; i < XENNET_MAX_RING_PAGES; i++) {
> + info->tx_ring_ref[i] = GRANT_INVALID_REF;
> + info->rx_ring_ref[i] = GRANT_INVALID_REF;
> + }
> info->rx.sring = NULL;
> info->tx.sring = NULL;
> netdev->irq = 0;
> @@ -1516,50 +1526,100 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info)
> goto fail;
> }
>
> - txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
> + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
> + "max-tx-ring-page-order", "%u",
> + &max_tx_ring_page_order);
> + if (err < 0) {
> + info->tx_ring_page_order = 0;
> + dev_info(&dev->dev, "single tx ring\n");
> + } else {
> + if (max_tx_ring_page_order > XENNET_MAX_RING_PAGE_ORDER) {
> + dev_info(&dev->dev,
> + "backend ring page order %d too large, clamp to %d\n",
> + max_tx_ring_page_order,
> + XENNET_MAX_RING_PAGE_ORDER);
> + max_tx_ring_page_order = XENNET_MAX_RING_PAGE_ORDER;
> + }
> + info->tx_ring_page_order = max_tx_ring_page_order;
> + dev_info(&dev->dev, "multi-page tx ring, order = %d\n",
> + info->tx_ring_page_order);
> + }
> + info->tx_ring_pages = (1U << info->tx_ring_page_order);
> +
> + txs = (struct xen_netif_tx_sring *)
> + __get_free_pages(__GFP_ZERO | GFP_NOIO | __GFP_HIGH,
> + info->tx_ring_page_order);
> if (!txs) {
> err = -ENOMEM;
> xenbus_dev_fatal(dev, err, "allocating tx ring page");
> goto fail;
> }
> SHARED_RING_INIT(txs);
> - FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE);
> + FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE * info->tx_ring_pages);
> +
> + err = xenbus_grant_ring(dev, txs, info->tx_ring_pages,
> + info->tx_ring_ref);
> + if (err < 0)
> + goto grant_tx_ring_fail;
>
> - err = xenbus_grant_ring(dev, txs, 1, grefs);
> + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend,
> + "max-rx-ring-page-order", "%u",
> + &max_rx_ring_page_order);
> if (err < 0) {
> - free_page((unsigned long)txs);
> - goto fail;
> + info->rx_ring_page_order = 0;
> + dev_info(&dev->dev, "single rx ring\n");
> + } else {
> + if (max_rx_ring_page_order > XENNET_MAX_RING_PAGE_ORDER) {
> + dev_info(&dev->dev,
> + "backend ring page order %d too large, clamp to %d\n",
> + max_rx_ring_page_order,
> + XENNET_MAX_RING_PAGE_ORDER);
> + max_rx_ring_page_order = XENNET_MAX_RING_PAGE_ORDER;
> + }
> + info->rx_ring_page_order = max_rx_ring_page_order;
> + dev_info(&dev->dev, "multi-page rx ring, order = %d\n",
> + info->rx_ring_page_order);
> }
> + info->rx_ring_pages = (1U << info->rx_ring_page_order);
>
> - info->tx_ring_ref = grefs[0];
> - rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH);
> + rxs = (struct xen_netif_rx_sring *)
> + __get_free_pages(__GFP_ZERO | GFP_NOIO | __GFP_HIGH,
> + info->rx_ring_page_order);
> if (!rxs) {
> err = -ENOMEM;
> xenbus_dev_fatal(dev, err, "allocating rx ring page");
> - goto fail;
> + goto alloc_rx_ring_fail;
> }
> SHARED_RING_INIT(rxs);
> - FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE);
> + FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE * info->rx_ring_pages);
>
> - err = xenbus_grant_ring(dev, rxs, 1, grefs);
> - if (err < 0) {
> - free_page((unsigned long)rxs);
> - goto fail;
> - }
> - info->rx_ring_ref = grefs[0];
> + err = xenbus_grant_ring(dev, rxs, info->rx_ring_pages,
> + info->rx_ring_ref);
> + if (err < 0)
> + goto grant_rx_ring_fail;
>
> err = xenbus_alloc_evtchn(dev, &info->evtchn);
> if (err)
> - goto fail;
> + goto alloc_evtchn_fail;
>
> err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt,
> 0, netdev->name, netdev);
> if (err < 0)
> - goto fail;
> + goto bind_fail;
> netdev->irq = err;
> return 0;
>
> - fail:
> +bind_fail:
> + xenbus_free_evtchn(dev, info->evtchn);
> +alloc_evtchn_fail:
> + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring);
> +grant_rx_ring_fail:
> + free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order);
> +alloc_rx_ring_fail:
> + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring);
> +grant_tx_ring_fail:
> + free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order);
> +fail:
> return err;
> }
>
> @@ -1570,6 +1630,7 @@ static int talk_to_netback(struct xenbus_device *dev,
> const char *message;
> struct xenbus_transaction xbt;
> int err;
> + int i;
>
> /* Create shared ring, alloc event channel. */
> err = setup_netfront(dev, info);
> @@ -1583,18 +1644,58 @@ again:
> goto destroy_ring;
> }
>
> - err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u",
> - info->tx_ring_ref);
> - if (err) {
> - message = "writing tx ring-ref";
> - goto abort_transaction;
> + if (info->tx_ring_page_order == 0) {
> + err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u",
> + info->tx_ring_ref[0]);
> + if (err) {
> + message = "writing tx ring-ref";
> + goto abort_transaction;
> + }
> + } else {
> + err = xenbus_printf(xbt, dev->nodename, "tx-ring-order", "%u",
> + info->tx_ring_page_order);
> + if (err) {
> + message = "writing tx-ring-order";
> + goto abort_transaction;
> + }
> + for (i = 0; i < info->tx_ring_pages; i++) {
> + char name[sizeof("tx-ring-ref")+3];
> + snprintf(name, sizeof(name), "tx-ring-ref%u", i);
> + err = xenbus_printf(xbt, dev->nodename, name, "%u",
> + info->tx_ring_ref[i]);
> + if (err) {
> + message = "writing tx ring-ref";
> + goto abort_transaction;
> + }
> + }
> }
> - err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u",
> - info->rx_ring_ref);
> - if (err) {
> - message = "writing rx ring-ref";
> - goto abort_transaction;
> +
> + if (info->rx_ring_page_order == 0) {
> + err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u",
> + info->rx_ring_ref[0]);
> + if (err) {
> + message = "writing rx ring-ref";
> + goto abort_transaction;
> + }
> + } else {
> + err = xenbus_printf(xbt, dev->nodename, "rx-ring-order", "%u",
> + info->rx_ring_page_order);
> + if (err) {
> + message = "writing rx-ring-order";
> + goto abort_transaction;
> + }
> + for (i = 0; i < info->rx_ring_pages; i++) {
> + char name[sizeof("rx-ring-ref")+3];
> + snprintf(name, sizeof(name), "rx-ring-ref%u", i);
> + err = xenbus_printf(xbt, dev->nodename, name, "%u",
> + info->rx_ring_ref[i]);
> + if (err) {
> + message = "writing rx ring-ref";
> + goto abort_transaction;
> + }
> + }
> }
> +
> err = xenbus_printf(xbt, dev->nodename,
> "event-channel", "%u", info->evtchn);
> if (err) {
> @@ -1681,7 +1782,8 @@ static int xennet_connect(struct net_device *dev)
> xennet_release_tx_bufs(np);
>
> /* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */
> - for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) {
> + for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE(np->rx_ring_pages);
> + i++) {
> skb_frag_t *frag;
> const struct page *page;
> if (!np->rx_skbs[i])
> --
> 1.7.10.4
>
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diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c index 8bd75a1..de73a71 100644 --- a/drivers/net/xen-netfront.c +++ b/drivers/net/xen-netfront.c @@ -67,9 +67,19 @@ struct netfront_cb { #define GRANT_INVALID_REF 0 -#define NET_TX_RING_SIZE __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE) -#define NET_RX_RING_SIZE __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE) -#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE, 256) +#define XENNET_MAX_RING_PAGE_ORDER XENBUS_MAX_RING_PAGE_ORDER +#define XENNET_MAX_RING_PAGES (1U << XENNET_MAX_RING_PAGE_ORDER) + + +#define NET_TX_RING_SIZE(_nr_pages) \ + __CONST_RING_SIZE(xen_netif_tx, PAGE_SIZE * (_nr_pages)) +#define NET_RX_RING_SIZE(_nr_pages) \ + __CONST_RING_SIZE(xen_netif_rx, PAGE_SIZE * (_nr_pages)) + +#define XENNET_MAX_TX_RING_SIZE NET_TX_RING_SIZE(XENNET_MAX_RING_PAGES) +#define XENNET_MAX_RX_RING_SIZE NET_RX_RING_SIZE(XENNET_MAX_RING_PAGES) + +#define TX_MAX_TARGET min_t(int, NET_TX_RING_SIZE(1), 256) struct netfront_stats { u64 rx_packets; @@ -80,6 +90,11 @@ struct netfront_stats { }; struct netfront_info { + /* Statistics */ + struct netfront_stats __percpu *stats; + + unsigned long rx_gso_checksum_fixup; + struct list_head list; struct net_device *netdev; @@ -90,7 +105,9 @@ struct netfront_info { spinlock_t tx_lock; struct xen_netif_tx_front_ring tx; - int tx_ring_ref; + int tx_ring_ref[XENNET_MAX_RING_PAGES]; + unsigned int tx_ring_page_order; + unsigned int tx_ring_pages; /* * {tx,rx}_skbs store outstanding skbuffs. Free tx_skb entries @@ -104,36 +121,33 @@ struct netfront_info { union skb_entry { struct sk_buff *skb; unsigned long link; - } tx_skbs[NET_TX_RING_SIZE]; + } tx_skbs[XENNET_MAX_TX_RING_SIZE]; grant_ref_t gref_tx_head; - grant_ref_t grant_tx_ref[NET_TX_RING_SIZE]; + grant_ref_t grant_tx_ref[XENNET_MAX_TX_RING_SIZE]; unsigned tx_skb_freelist; spinlock_t rx_lock ____cacheline_aligned_in_smp; struct xen_netif_rx_front_ring rx; - int rx_ring_ref; + int rx_ring_ref[XENNET_MAX_RING_PAGES]; + unsigned int rx_ring_page_order; + unsigned int rx_ring_pages; /* Receive-ring batched refills. */ #define RX_MIN_TARGET 8 #define RX_DFL_MIN_TARGET 64 -#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE, 256) +#define RX_MAX_TARGET min_t(int, NET_RX_RING_SIZE(1), 256) unsigned rx_min_target, rx_max_target, rx_target; struct sk_buff_head rx_batch; struct timer_list rx_refill_timer; - struct sk_buff *rx_skbs[NET_RX_RING_SIZE]; + struct sk_buff *rx_skbs[XENNET_MAX_RX_RING_SIZE]; grant_ref_t gref_rx_head; - grant_ref_t grant_rx_ref[NET_RX_RING_SIZE]; - - unsigned long rx_pfn_array[NET_RX_RING_SIZE]; - struct multicall_entry rx_mcl[NET_RX_RING_SIZE+1]; - struct mmu_update rx_mmu[NET_RX_RING_SIZE]; - - /* Statistics */ - struct netfront_stats __percpu *stats; + grant_ref_t grant_rx_ref[XENNET_MAX_RX_RING_SIZE]; - unsigned long rx_gso_checksum_fixup; + unsigned long rx_pfn_array[XENNET_MAX_RX_RING_SIZE]; + struct multicall_entry rx_mcl[XENNET_MAX_RX_RING_SIZE+1]; + struct mmu_update rx_mmu[XENNET_MAX_RX_RING_SIZE]; }; struct netfront_rx_info { @@ -171,15 +185,15 @@ static unsigned short get_id_from_freelist(unsigned *head, return id; } -static int xennet_rxidx(RING_IDX idx) +static int xennet_rxidx(RING_IDX idx, struct netfront_info *info) { - return idx & (NET_RX_RING_SIZE - 1); + return idx & (NET_RX_RING_SIZE(info->rx_ring_pages) - 1); } static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np, RING_IDX ri) { - int i = xennet_rxidx(ri); + int i = xennet_rxidx(ri, np); struct sk_buff *skb = np->rx_skbs[i]; np->rx_skbs[i] = NULL; return skb; @@ -188,7 +202,7 @@ static struct sk_buff *xennet_get_rx_skb(struct netfront_info *np, static grant_ref_t xennet_get_rx_ref(struct netfront_info *np, RING_IDX ri) { - int i = xennet_rxidx(ri); + int i = xennet_rxidx(ri, np); grant_ref_t ref = np->grant_rx_ref[i]; np->grant_rx_ref[i] = GRANT_INVALID_REF; return ref; @@ -301,7 +315,7 @@ no_skb: skb->dev = dev; - id = xennet_rxidx(req_prod + i); + id = xennet_rxidx(req_prod + i, np); BUG_ON(np->rx_skbs[id]); np->rx_skbs[id] = skb; @@ -653,7 +667,7 @@ static int xennet_close(struct net_device *dev) static void xennet_move_rx_slot(struct netfront_info *np, struct sk_buff *skb, grant_ref_t ref) { - int new = xennet_rxidx(np->rx.req_prod_pvt); + int new = xennet_rxidx(np->rx.req_prod_pvt, np); BUG_ON(np->rx_skbs[new]); np->rx_skbs[new] = skb; @@ -1109,7 +1123,7 @@ static void xennet_release_tx_bufs(struct netfront_info *np) struct sk_buff *skb; int i; - for (i = 0; i < NET_TX_RING_SIZE; i++) { + for (i = 0; i < NET_TX_RING_SIZE(np->tx_ring_pages); i++) { /* Skip over entries which are actually freelist references */ if (skb_entry_is_link(&np->tx_skbs[i])) continue; @@ -1143,7 +1157,7 @@ static void xennet_release_rx_bufs(struct netfront_info *np) spin_lock_bh(&np->rx_lock); - for (id = 0; id < NET_RX_RING_SIZE; id++) { + for (id = 0; id < NET_RX_RING_SIZE(np->rx_ring_pages); id++) { ref = np->grant_rx_ref[id]; if (ref == GRANT_INVALID_REF) { unused++; @@ -1324,13 +1338,13 @@ static struct net_device *xennet_create_dev(struct xenbus_device *dev) /* Initialise tx_skbs as a free chain containing every entry. */ np->tx_skb_freelist = 0; - for (i = 0; i < NET_TX_RING_SIZE; i++) { + for (i = 0; i < XENNET_MAX_TX_RING_SIZE; i++) { skb_entry_set_link(&np->tx_skbs[i], i+1); np->grant_tx_ref[i] = GRANT_INVALID_REF; } /* Clear out rx_skbs */ - for (i = 0; i < NET_RX_RING_SIZE; i++) { + for (i = 0; i < XENNET_MAX_RX_RING_SIZE; i++) { np->rx_skbs[i] = NULL; np->grant_rx_ref[i] = GRANT_INVALID_REF; } @@ -1428,13 +1442,6 @@ static int netfront_probe(struct xenbus_device *dev, return err; } -static void xennet_end_access(int ref, void *page) -{ - /* This frees the page as a side-effect */ - if (ref != GRANT_INVALID_REF) - gnttab_end_foreign_access(ref, 0, (unsigned long)page); -} - static void xennet_disconnect_backend(struct netfront_info *info) { /* Stop old i/f to prevent errors whilst we rebuild the state. */ @@ -1448,12 +1455,12 @@ static void xennet_disconnect_backend(struct netfront_info *info) unbind_from_irqhandler(info->netdev->irq, info->netdev); info->evtchn = info->netdev->irq = 0; - /* End access and free the pages */ - xennet_end_access(info->tx_ring_ref, info->tx.sring); - xennet_end_access(info->rx_ring_ref, info->rx.sring); + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring); + free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order); + + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring); + free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order); - info->tx_ring_ref = GRANT_INVALID_REF; - info->rx_ring_ref = GRANT_INVALID_REF; info->tx.sring = NULL; info->rx.sring = NULL; } @@ -1501,11 +1508,14 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) struct xen_netif_tx_sring *txs; struct xen_netif_rx_sring *rxs; int err; - int grefs[1]; struct net_device *netdev = info->netdev; + unsigned int max_tx_ring_page_order, max_rx_ring_page_order; + int i; - info->tx_ring_ref = GRANT_INVALID_REF; - info->rx_ring_ref = GRANT_INVALID_REF; + for (i = 0; i < XENNET_MAX_RING_PAGES; i++) { + info->tx_ring_ref[i] = GRANT_INVALID_REF; + info->rx_ring_ref[i] = GRANT_INVALID_REF; + } info->rx.sring = NULL; info->tx.sring = NULL; netdev->irq = 0; @@ -1516,50 +1526,100 @@ static int setup_netfront(struct xenbus_device *dev, struct netfront_info *info) goto fail; } - txs = (struct xen_netif_tx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, + "max-tx-ring-page-order", "%u", + &max_tx_ring_page_order); + if (err < 0) { + info->tx_ring_page_order = 0; + dev_info(&dev->dev, "single tx ring\n"); + } else { + if (max_tx_ring_page_order > XENNET_MAX_RING_PAGE_ORDER) { + dev_info(&dev->dev, + "backend ring page order %d too large, clamp to %d\n", + max_tx_ring_page_order, + XENNET_MAX_RING_PAGE_ORDER); + max_tx_ring_page_order = XENNET_MAX_RING_PAGE_ORDER; + } + info->tx_ring_page_order = max_tx_ring_page_order; + dev_info(&dev->dev, "multi-page tx ring, order = %d\n", + info->tx_ring_page_order); + } + info->tx_ring_pages = (1U << info->tx_ring_page_order); + + txs = (struct xen_netif_tx_sring *) + __get_free_pages(__GFP_ZERO | GFP_NOIO | __GFP_HIGH, + info->tx_ring_page_order); if (!txs) { err = -ENOMEM; xenbus_dev_fatal(dev, err, "allocating tx ring page"); goto fail; } SHARED_RING_INIT(txs); - FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE); + FRONT_RING_INIT(&info->tx, txs, PAGE_SIZE * info->tx_ring_pages); + + err = xenbus_grant_ring(dev, txs, info->tx_ring_pages, + info->tx_ring_ref); + if (err < 0) + goto grant_tx_ring_fail; - err = xenbus_grant_ring(dev, txs, 1, grefs); + err = xenbus_scanf(XBT_NIL, info->xbdev->otherend, + "max-rx-ring-page-order", "%u", + &max_rx_ring_page_order); if (err < 0) { - free_page((unsigned long)txs); - goto fail; + info->rx_ring_page_order = 0; + dev_info(&dev->dev, "single rx ring\n"); + } else { + if (max_rx_ring_page_order > XENNET_MAX_RING_PAGE_ORDER) { + dev_info(&dev->dev, + "backend ring page order %d too large, clamp to %d\n", + max_rx_ring_page_order, + XENNET_MAX_RING_PAGE_ORDER); + max_rx_ring_page_order = XENNET_MAX_RING_PAGE_ORDER; + } + info->rx_ring_page_order = max_rx_ring_page_order; + dev_info(&dev->dev, "multi-page rx ring, order = %d\n", + info->rx_ring_page_order); } + info->rx_ring_pages = (1U << info->rx_ring_page_order); - info->tx_ring_ref = grefs[0]; - rxs = (struct xen_netif_rx_sring *)get_zeroed_page(GFP_NOIO | __GFP_HIGH); + rxs = (struct xen_netif_rx_sring *) + __get_free_pages(__GFP_ZERO | GFP_NOIO | __GFP_HIGH, + info->rx_ring_page_order); if (!rxs) { err = -ENOMEM; xenbus_dev_fatal(dev, err, "allocating rx ring page"); - goto fail; + goto alloc_rx_ring_fail; } SHARED_RING_INIT(rxs); - FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE); + FRONT_RING_INIT(&info->rx, rxs, PAGE_SIZE * info->rx_ring_pages); - err = xenbus_grant_ring(dev, rxs, 1, grefs); - if (err < 0) { - free_page((unsigned long)rxs); - goto fail; - } - info->rx_ring_ref = grefs[0]; + err = xenbus_grant_ring(dev, rxs, info->rx_ring_pages, + info->rx_ring_ref); + if (err < 0) + goto grant_rx_ring_fail; err = xenbus_alloc_evtchn(dev, &info->evtchn); if (err) - goto fail; + goto alloc_evtchn_fail; err = bind_evtchn_to_irqhandler(info->evtchn, xennet_interrupt, 0, netdev->name, netdev); if (err < 0) - goto fail; + goto bind_fail; netdev->irq = err; return 0; - fail: +bind_fail: + xenbus_free_evtchn(dev, info->evtchn); +alloc_evtchn_fail: + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->rx.sring); +grant_rx_ring_fail: + free_pages((unsigned long)info->rx.sring, info->rx_ring_page_order); +alloc_rx_ring_fail: + xenbus_unmap_ring_vfree(info->xbdev, (void *)info->tx.sring); +grant_tx_ring_fail: + free_pages((unsigned long)info->tx.sring, info->tx_ring_page_order); +fail: return err; } @@ -1570,6 +1630,7 @@ static int talk_to_netback(struct xenbus_device *dev, const char *message; struct xenbus_transaction xbt; int err; + int i; /* Create shared ring, alloc event channel. */ err = setup_netfront(dev, info); @@ -1583,18 +1644,58 @@ again: goto destroy_ring; } - err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u", - info->tx_ring_ref); - if (err) { - message = "writing tx ring-ref"; - goto abort_transaction; + if (info->tx_ring_page_order == 0) { + err = xenbus_printf(xbt, dev->nodename, "tx-ring-ref", "%u", + info->tx_ring_ref[0]); + if (err) { + message = "writing tx ring-ref"; + goto abort_transaction; + } + } else { + err = xenbus_printf(xbt, dev->nodename, "tx-ring-order", "%u", + info->tx_ring_page_order); + if (err) { + message = "writing tx-ring-order"; + goto abort_transaction; + } + for (i = 0; i < info->tx_ring_pages; i++) { + char name[sizeof("tx-ring-ref")+3]; + snprintf(name, sizeof(name), "tx-ring-ref%u", i); + err = xenbus_printf(xbt, dev->nodename, name, "%u", + info->tx_ring_ref[i]); + if (err) { + message = "writing tx ring-ref"; + goto abort_transaction; + } + } } - err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u", - info->rx_ring_ref); - if (err) { - message = "writing rx ring-ref"; - goto abort_transaction; + + if (info->rx_ring_page_order == 0) { + err = xenbus_printf(xbt, dev->nodename, "rx-ring-ref", "%u", + info->rx_ring_ref[0]); + if (err) { + message = "writing rx ring-ref"; + goto abort_transaction; + } + } else { + err = xenbus_printf(xbt, dev->nodename, "rx-ring-order", "%u", + info->rx_ring_page_order); + if (err) { + message = "writing rx-ring-order"; + goto abort_transaction; + } + for (i = 0; i < info->rx_ring_pages; i++) { + char name[sizeof("rx-ring-ref")+3]; + snprintf(name, sizeof(name), "rx-ring-ref%u", i); + err = xenbus_printf(xbt, dev->nodename, name, "%u", + info->rx_ring_ref[i]); + if (err) { + message = "writing rx ring-ref"; + goto abort_transaction; + } + } } + err = xenbus_printf(xbt, dev->nodename, "event-channel", "%u", info->evtchn); if (err) { @@ -1681,7 +1782,8 @@ static int xennet_connect(struct net_device *dev) xennet_release_tx_bufs(np); /* Step 2: Rebuild the RX buffer freelist and the RX ring itself. */ - for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE; i++) { + for (requeue_idx = 0, i = 0; i < NET_RX_RING_SIZE(np->rx_ring_pages); + i++) { skb_frag_t *frag; const struct page *page; if (!np->rx_skbs[i])
Signed-off-by: Wei Liu <wei.liu2@citrix.com> --- drivers/net/xen-netfront.c | 246 +++++++++++++++++++++++++++++++------------- 1 file changed, 174 insertions(+), 72 deletions(-)