The commit is pushed to "branch-rh7-3.10.0-693.17.1.vz7.43.x-ovz" and will 
appear at
after rh7-3.10.0-693.17.1.vz7.43.4
commit 497a0449ec62f49bc2f29f2e1a90154c6b536fa3
Author: Shaohua Li <>
Date:   Wed Feb 14 13:17:33 2018 +0300

    ms/net: don't wait for order-3 page allocation
    We saw excessive direct memory compaction triggered by skb_page_frag_refill.
    This causes performance issues and add latency. Commit 5640f7685831e0
    introduces the order-3 allocation. According to the changelog, the order-3
    allocation isn't a must-have but to improve performance. But direct memory
    compaction has high overhead. The benefit of order-3 allocation can't
    compensate the overhead of direct memory compaction.
    This patch makes the order-3 page allocation atomic. If there is no memory
    pressure and memory isn't fragmented, the alloction will still success, so 
    don't sacrifice the order-3 benefit here. If the atomic allocation fails,
    direct memory compaction will not be triggered, skb_page_frag_refill will
    fallback to order-0 immediately, hence the direct memory compaction 
overhead is
    avoided. In the allocation failure case, kswapd is waken up and doing
    compaction, so chances are allocation could success next time.
    alloc_skb_with_frags is the same.
    The mellanox driver does similar thing, if this is accepted, we must fix
    the driver too.
    V3: fix the same issue in alloc_skb_with_frags as pointed out by Eric
    V2: make the changelog clearer
    Cc: Eric Dumazet <>
    Cc: Chris Mason <>
    Cc: Debabrata Banerjee <>
    Signed-off-by: Shaohua Li <>
    Acked-by: Eric Dumazet <>
    Signed-off-by: David S. Miller <>
    (cherry picked from commit fb05e7a89f500cfc06ae277bdc911b281928995d)
    Signed-off-by: Andrey Ryabinin <>
 net/core/skbuff.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 4147d7219589..dca9d1d9676b 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -4360,7 +4360,7 @@ struct sk_buff *alloc_skb_with_frags(unsigned long 
                while (order) {
                        if (npages >= 1 << order) {
-                               page = alloc_pages(gfp_mask |
+                               page = alloc_pages((gfp_mask & ~__GFP_WAIT) |
                                                   __GFP_COMP |
                                                   __GFP_NOWARN |
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