From 2d81e67f5393f129860977a0e3b9bf9d0332ee45 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Sat, 21 Jul 2012 10:54:24 +1000 Subject: [PATCH] netvm: propagate page->pfmemalloc from skb_alloc_page to skb The skb->pfmemalloc flag gets set to true iff during the slab allocation of data in __alloc_skb that the the PFMEMALLOC reserves were used. If page splitting is used, it is possible that pages will be allocated from the PFMEMALLOC reserve without propagating this information to the skb. This patch propagates page->pfmemalloc from pages allocated for fragments to the skb. It works by reintroducing and expanding the skb_alloc_page() API to take an skb. If the page was allocated from pfmemalloc reserves, it is automatically copied. If the driver allocates the page before the skb, it should call skb_propagate_pfmemalloc() after the skb is allocated to ensure the flag is copied properly. Failure to do so is not critical. The resulting driver may perform slower if it is used for swap-over-NBD or swap-over-NFS but it should not result in failure. [davem@davemloft.net: API rename and consistency] Signed-off-by: Mel Gorman Acked-by: David S. Miller Cc: Neil Brown Cc: Peter Zijlstra Cc: Mike Christie Cc: Eric B Munson Cc: Eric Dumazet Cc: Sebastian Andrzej Siewior Cc: Mel Gorman Cc: Christoph Lameter Signed-off-by: Andrew Morton --- drivers/net/ethernet/chelsio/cxgb4/sge.c | 2 +- drivers/net/ethernet/chelsio/cxgb4vf/sge.c | 2 +- drivers/net/ethernet/intel/igb/igb_main.c | 2 +- drivers/net/ethernet/intel/ixgbe/ixgbe_main.c | 4 +- .../net/ethernet/intel/ixgbevf/ixgbevf_main.c | 1 + drivers/net/usb/cdc-phonet.c | 2 +- drivers/usb/gadget/f_phonet.c | 2 +- include/linux/skbuff.h | 55 +++++++++++++++++++ 8 files changed, 63 insertions(+), 7 deletions(-) diff --git a/drivers/net/ethernet/chelsio/cxgb4/sge.c b/drivers/net/ethernet/chelsio/cxgb4/sge.c index 8596acaa402b..d49933ed551f 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4/sge.c @@ -528,7 +528,7 @@ static unsigned int refill_fl(struct adapter *adap, struct sge_fl *q, int n, #endif while (n--) { - pg = alloc_page(gfp); + pg = __skb_alloc_page(gfp, NULL); if (unlikely(!pg)) { q->alloc_failed++; break; diff --git a/drivers/net/ethernet/chelsio/cxgb4vf/sge.c b/drivers/net/ethernet/chelsio/cxgb4vf/sge.c index f2d1ecdcaf98..8877fbfefb63 100644 --- a/drivers/net/ethernet/chelsio/cxgb4vf/sge.c +++ b/drivers/net/ethernet/chelsio/cxgb4vf/sge.c @@ -653,7 +653,7 @@ static unsigned int refill_fl(struct adapter *adapter, struct sge_fl *fl, alloc_small_pages: while (n--) { - page = alloc_page(gfp | __GFP_NOWARN | __GFP_COLD); + page = __skb_alloc_page(gfp | __GFP_NOWARN, NULL); if (unlikely(!page)) { fl->alloc_failed++; break; diff --git a/drivers/net/ethernet/intel/igb/igb_main.c b/drivers/net/ethernet/intel/igb/igb_main.c index 1050411e7ca3..b7c2d5050572 100644 --- a/drivers/net/ethernet/intel/igb/igb_main.c +++ b/drivers/net/ethernet/intel/igb/igb_main.c @@ -6235,7 +6235,7 @@ static bool igb_alloc_mapped_page(struct igb_ring *rx_ring, return true; if (!page) { - page = alloc_page(GFP_ATOMIC | __GFP_COLD); + page = __skb_alloc_page(GFP_ATOMIC, bi->skb); bi->page = page; if (unlikely(!page)) { rx_ring->rx_stats.alloc_failed++; diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c index 3b6784cf134a..97084d6e04d4 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c @@ -1140,8 +1140,8 @@ static bool ixgbe_alloc_mapped_page(struct ixgbe_ring *rx_ring, /* alloc new page for storage */ if (likely(!page)) { - page = alloc_pages(GFP_ATOMIC | __GFP_COLD | __GFP_COMP, - ixgbe_rx_pg_order(rx_ring)); + page = __skb_alloc_pages(GFP_ATOMIC | __GFP_COLD | __GFP_COMP, + bi->skb, ixgbe_rx_pg_order(rx_ring)); if (unlikely(!page)) { rx_ring->rx_stats.alloc_rx_page_failed++; return false; diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c index 3f9841d619ad..cd7dff624ab2 100644 --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c @@ -353,6 +353,7 @@ static void ixgbevf_alloc_rx_buffers(struct ixgbevf_adapter *adapter, goto no_buffers; } + skb_propagate_pfmemalloc(bi->page, skb); bi->skb = skb; } if (!bi->dma) { diff --git a/drivers/net/usb/cdc-phonet.c b/drivers/net/usb/cdc-phonet.c index 187c144c5e5b..64610048ce87 100644 --- a/drivers/net/usb/cdc-phonet.c +++ b/drivers/net/usb/cdc-phonet.c @@ -130,7 +130,7 @@ static int rx_submit(struct usbpn_dev *pnd, struct urb *req, gfp_t gfp_flags) struct page *page; int err; - page = alloc_page(gfp_flags); + page = __skb_alloc_page(gfp_flags | __GFP_NOMEMALLOC, NULL); if (!page) return -ENOMEM; diff --git a/drivers/usb/gadget/f_phonet.c b/drivers/usb/gadget/f_phonet.c index 965a6293206a..8ee9268fe253 100644 --- a/drivers/usb/gadget/f_phonet.c +++ b/drivers/usb/gadget/f_phonet.c @@ -301,7 +301,7 @@ pn_rx_submit(struct f_phonet *fp, struct usb_request *req, gfp_t gfp_flags) struct page *page; int err; - page = alloc_page(gfp_flags); + page = __skb_alloc_page(gfp_flags | __GFP_NOMEMALLOC, NULL); if (!page) return -ENOMEM; diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index b814bb8fd5ab..7632c87da2c9 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -1774,6 +1774,61 @@ static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev, return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC); } +/* + * __skb_alloc_page - allocate pages for ps-rx on a skb and preserve pfmemalloc data + * @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX + * @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used + * @order: size of the allocation + * + * Allocate a new page. + * + * %NULL is returned if there is no free memory. +*/ +static inline struct page *__skb_alloc_pages(gfp_t gfp_mask, + struct sk_buff *skb, + unsigned int order) +{ + struct page *page; + + gfp_mask |= __GFP_COLD; + + if (!(gfp_mask & __GFP_NOMEMALLOC)) + gfp_mask |= __GFP_MEMALLOC; + + page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, order); + if (skb && page && page->pfmemalloc) + skb->pfmemalloc = true; + + return page; +} + +/** + * __skb_alloc_page - allocate a page for ps-rx for a given skb and preserve pfmemalloc data + * @gfp_mask: alloc_pages_node mask. Set __GFP_NOMEMALLOC if not for network packet RX + * @skb: skb to set pfmemalloc on if __GFP_MEMALLOC is used + * + * Allocate a new page. + * + * %NULL is returned if there is no free memory. + */ +static inline struct page *__skb_alloc_page(gfp_t gfp_mask, + struct sk_buff *skb) +{ + return __skb_alloc_pages(gfp_mask, skb, 0); +} + +/** + * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page + * @page: The page that was allocated from skb_alloc_page + * @skb: The skb that may need pfmemalloc set + */ +static inline void skb_propagate_pfmemalloc(struct page *page, + struct sk_buff *skb) +{ + if (page && page->pfmemalloc) + skb->pfmemalloc = true; +} + /** * skb_frag_page - retrieve the page refered to by a paged fragment * @frag: the paged fragment -- 2.39.5