kernel/linux.git/include/linux/skbuff.h, branch v4.10.9

mm: rename __alloc_page_frag to page_frag_alloc and __free_page_frag to page_frag_free

2017-01-11T02:31:55+00:00

Patch series "Page fragment updates", v4. This patch series takes care of a few cleanups for the page fragments API. First we do some renames so that things are much more consistent. First we move the page_frag_ portion of the name to the front of the functions names. Secondly we split out the cache specific functions from the other page fragment functions by adding the word "cache" to the name. Finally I added a bit of documentation that will hopefully help to explain some of this. I plan to revisit this later as we get things more ironed out in the near future with the changes planned for the DMA setup to support eXpress Data Path. This patch (of 3): This patch renames the page frag functions to be more consistent with other APIs. Specifically we place the name page_frag first in the name and then have either an alloc or free call name that we append as the suffix. This makes it a bit clearer in terms of naming. In addition we drop the leading double underscores since we are technically no longer a backing interface and instead the front end that is called from the networking APIs. Link: http://lkml.kernel.org/r/20170104023854.13451.67390.stgit@localhost.localdomain Signed-off-by: Alexander Duyck Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

ktime: Cleanup ktime_set() usage

2016-12-25T16:21:22+00:00

ktime_set(S,N) was required for the timespec storage type and is still useful for situations where a Seconds and Nanoseconds part of a time value needs to be converted. For anything where the Seconds argument is 0, this is pointless and can be replaced with a simple assignment. Signed-off-by: Thomas Gleixner Cc: Peter Zijlstra

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2016-12-16T18:24:44+00:00

Pull vfs updates from Al Viro: - more ->d_init() stuff (work.dcache) - pathname resolution cleanups (work.namei) - a few missing iov_iter primitives - copy_from_iter_full() and friends. Either copy the full requested amount, advance the iterator and return true, or fail, return false and do _not_ advance the iterator. Quite a few open-coded callers converted (and became more readable and harder to fuck up that way) (work.iov_iter) - several assorted patches, the big one being logfs removal * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: logfs: remove from tree vfs: fix put_compat_statfs64() does not handle errors namei: fold should_follow_link() with the step into not-followed link namei: pass both WALK_GET and WALK_MORE to should_follow_link() namei: invert WALK_PUT logics namei: shift interpretation of LOOKUP_FOLLOW inside should_follow_link() namei: saner calling conventions for mountpoint_last() namei.c: get rid of user_path_parent() switch getfrag callbacks to ..._full() primitives make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only on success [iov_iter] new primitives - copy_from_iter_full() and friends don't open-code file_inode() ceph: switch to use of ->d_init() ceph: unify dentry_operations instances lustre: switch to use of ->d_init()

udp: copy skb->truesize in the first cache line

2016-12-10T03:12:21+00:00

In UDP RX handler, we currently clear skb->dev before skb is added to receive queue, because device pointer is no longer available once we exit from RCU section. Since this first cache line is always hot, lets reuse this space to store skb->truesize and thus avoid a cache line miss at udp_recvmsg()/udp_skb_destructor time while receive queue spinlock is held. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller

udp: under rx pressure, try to condense skbs

2016-12-08T18:25:07+00:00

Under UDP flood, many softirq producers try to add packets to UDP receive queue, and one user thread is burning one cpu trying to dequeue packets as fast as possible. Two parts of the per packet cost are : - copying payload from kernel space to user space, - freeing memory pieces associated with skb. If socket is under pressure, softirq handler(s) can try to pull in skb->head the payload of the packet if it fits. Meaning the softirq handler(s) can free/reuse the page fragment immediately, instead of letting udp_recvmsg() do this hundreds of usec later, possibly from another node. Additional gains : - We reduce skb->truesize and thus can store more packets per SO_RCVBUF - We avoid cache line misses at copyout() time and consume_skb() time, and avoid one put_page() with potential alien freeing on NUMA hosts. This comes at the cost of a copy, bounded to available tail room, which is usually small. (We might have to fix GRO_MAX_HEAD which looks bigger than necessary) This patch gave me about 5 % increase in throughput in my tests. skb_condense() helper could probably used in other contexts. Signed-off-by: Eric Dumazet Cc: Paolo Abeni Signed-off-by: David S. Miller

make skb_add_data,{_nocache}() and skb_copy_to_page_nocache() advance only on success

2016-12-05T19:34:30+00:00

Signed-off-by: Al Viro

net: fix bogus cast in skb_pagelen() and use unsigned variables

2016-11-20T03:11:25+00:00

1) cast to "int" is unnecessary: u8 will be promoted to int before decrementing, small positive numbers fit into "int", so their values won't be changed during promotion. Once everything is int including loop counters, signedness doesn't matter: 32-bit operations will stay 32-bit operations. But! Someone tried to make this loop smart by making everything of the same type apparently in an attempt to optimise it. Do the optimization, just differently. Do the cast where it matters. :^) 2) frag size is unsigned entity and sum of fragments sizes is also unsigned. Make everything unsigned, leave no MOVSX instruction behind. add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-4 (-4) function old new delta skb_cow_data 835 834 -1 ip_do_fragment 2549 2548 -1 ip6_fragment 3130 3128 -2 Total: Before=154865032, After=154865028, chg -0.00% Signed-off-by: Alexey Dobriyan Signed-off-by: David S. Miller

udp: do fwd memory scheduling on dequeue

2016-11-07T18:24:41+00:00

A new argument is added to __skb_recv_datagram to provide an explicit skb destructor, invoked under the receive queue lock. The UDP protocol uses such argument to perform memory reclaiming on dequeue, so that the UDP protocol does not set anymore skb->desctructor. Instead explicit memory reclaiming is performed at close() time and when skbs are removed from the receive queue. The in kernel UDP protocol users now need to call a skb_recv_udp() variant instead of skb_recv_datagram() to properly perform memory accounting on dequeue. Overall, this allows acquiring only once the receive queue lock on dequeue. Tested using pktgen with random src port, 64 bytes packet, wire-speed on a 10G link as sender and udp_sink as the receiver, using an l4 tuple rxhash to stress the contention, and one or more udp_sink instances with reuseport. nr sinks vanilla patched 1 440 560 3 2150 2300 6 3650 3800 9 4450 4600 12 6250 6450 v1 -> v2: - do rmem and allocated memory scheduling under the receive lock - do bulk scheduling in first_packet_length() and in udp_destruct_sock() - avoid the typdef for the dequeue callback Suggested-by: Eric Dumazet Acked-by: Hannes Frederic Sowa Signed-off-by: Paolo Abeni Acked-by: Eric Dumazet Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2016-10-30T16:42:58+00:00

Mostly simple overlapping changes. For example, David Ahern's adjacency list revamp in 'net-next' conflicted with an adjacency list traversal bug fix in 'net'. Signed-off-by: David S. Miller

flow_dissector: __skb_get_hash_symmetric arg can be const

2016-10-29T19:10:21+00:00

Signed-off-by: Florian Westphal Signed-off-by: David S. Miller