1. 17 Mar, 2014 15 commits
    • David S. Miller's avatar
      Merge branch 'netpoll-next' · 7c169445
      David S. Miller authored
      Eric W. Biederman says:
      
      ====================
      netpoll: Cleanup received packet processing
      
      This is the long-winded, careful, and polite version of removing the netpoll
      receive packet processing.
      
      First I untangle the code in small steps.  Then I modify the code to not
      force reception and dropping of packets when we are transmiting a packet
      with netpoll.  Finally I move all of the packet reception under
      CONFIG_NETPOLL_TRAP and delete CONFIG_NETPOLL_TRAP.
      
      If someone wants to do a stable backport of these patches, it would
      require backporting the first 18 patches that handle the budget == 0 in
      the networking drivers, and the first 6 of these patches.
      
      If anyone wants to resurrect netpoll packet reception someday it should
      just be a matter of reverting the last patch.
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7c169445
    • Eric W. Biederman's avatar
      netpoll: Remove dead packet receive code (CONFIG_NETPOLL_TRAP) · 9c62a68d
      Eric W. Biederman authored
      The netpoll packet receive code only becomes active if the netpoll
      rx_skb_hook is implemented, and there is not a single implementation
      of the netpoll rx_skb_hook in the kernel.
      
      All of the out of tree implementations I have found all call
      netpoll_poll which was removed from the kernel in 2011, so this
      change should not add any additional breakage.
      
      There are problems with the netpoll packet receive code.  __netpoll_rx
      does not call dev_kfree_skb_irq or dev_kfree_skb_any in hard irq
      context.  netpoll_neigh_reply leaks every skb it receives.  Reception
      of packets does not work successfully on stacked devices (aka bonding,
      team, bridge, and vlans).
      
      Given that the netpoll packet receive code is buggy, there are no
      out of tree users that will be merged soon, and the code has
      not been used for in tree for a decade let's just remove it.
      
      Reverting this commit can server as a starting point for anyone
      who wants to resurrect netpoll packet reception support.
      Acked-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9c62a68d
    • Eric W. Biederman's avatar
      netpoll: Move all receive processing under CONFIG_NETPOLL_TRAP · e1bd4d3d
      Eric W. Biederman authored
      Make rx_skb_hook, and rx in struct netpoll depend on
      CONFIG_NETPOLL_TRAP Make rx_lock, rx_np, and neigh_tx in struct
      netpoll_info depend on CONFIG_NETPOLL_TRAP
      
      Make the functions netpoll_rx_on, netpoll_rx, and netpoll_receive_skb
      no-ops when CONFIG_NETPOLL_TRAP is not set.
      
      Only build netpoll_neigh_reply, checksum_udp service_neigh_queue,
      pkt_is_ns, and __netpoll_rx when CONFIG_NETPOLL_TRAP is defined.
      
      Add helper functions netpoll_trap_setup, netpoll_trap_setup_info,
      netpoll_trap_cleanup, and netpoll_trap_cleanup_info that initialize
      and cleanup the struct netpoll and struct netpoll_info receive
      specific fields when CONFIG_NETPOLL_TRAP is enabled and do nothing
      otherwise.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e1bd4d3d
    • Eric W. Biederman's avatar
      netpoll: Consolidate neigh_tx processing in service_neigh_queue · 18b37535
      Eric W. Biederman authored
      Move the bond slave device neigh_tx handling into service_neigh_queue.
      
      In connection with neigh_tx processing remove unnecessary tests of
      a NULL netpoll_info.  As the netpoll_poll_dev has already used
      and thus verified the existince of the netpoll_info.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      18b37535
    • Eric W. Biederman's avatar
      netpoll: Move netpoll_trap under CONFIG_NETPOLL_TRAP · ad8d4752
      Eric W. Biederman authored
      Now that we no longer need to receive packets to safely drain the
      network drivers receive queue move netpoll_trap and netpoll_set_trap
      under CONFIG_NETPOLL_TRAP
      
      Making netpoll_trap and netpoll_set_trap noop inline functions
      when CONFIG_NETPOLL_TRAP is not set.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ad8d4752
    • Eric W. Biederman's avatar
      netpoll: Don't drop all received packets. · b6bacd55
      Eric W. Biederman authored
      Change the strategy of netpoll from dropping all packets received
      during netpoll_poll_dev to calling napi poll with a budget of 0
      (to avoid processing drivers rx queue), and to ignore packets received
      with netif_rx (those will safely be placed on the backlog queue).
      
      All of the netpoll supporting drivers have been reviewed to ensure
      either thay use netif_rx or that a budget of 0 is supported by their
      napi poll routine and that a budget of 0 will not process the drivers
      rx queues.
      
      Not dropping packets makes NETPOLL_RX_DROP unnecesary so it is removed.
      
      npinfo->rx_flags is removed  as rx_flags with just the NETPOLL_RX_ENABLED
      flag becomes just a redundant mirror of list_empty(&npinfo->rx_np).
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b6bacd55
    • Eric W. Biederman's avatar
      netpoll: Add netpoll_rx_processing · ff607631
      Eric W. Biederman authored
      Add a helper netpoll_rx_processing that reports when netpoll has
      receive side processing to perform.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ff607631
    • Eric W. Biederman's avatar
      netpoll: Warn if more packets are processed than are budgeted · e97dc3fc
      Eric W. Biederman authored
      There is already a warning for this case in the normal netpoll path,
      but put a copy here in case how netpoll calls the poll functions
      causes a differenet result.
      
      netpoll will shortly call the napi poll routine with a budget 0 to
      avoid any rx packets being processed.  As nothing does that today
      we may encounter drivers that have problems so a netpoll specific
      warning seems desirable.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e97dc3fc
    • Eric W. Biederman's avatar
      netpoll: Visit all napi handlers in poll_napi · eb8143b4
      Eric W. Biederman authored
      In poll_napi loop through all of the napi handlers even when the
      budget falls to 0 to ensure that we process all of the tx_queues, and
      so that we continue to call into drivers when our initial budget is 0.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      eb8143b4
    • Eric W. Biederman's avatar
      netpoll: Pass budget into poll_napi · 9852fbec
      Eric W. Biederman authored
      This moves the control logic to the top level in netpoll_poll_dev
      instead of having it dispersed throughout netpoll_poll_dev,
      poll_napi and poll_one_napi.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9852fbec
    • Eric W. Biederman's avatar
      netpoll: move setting of NETPOLL_RX_DROP into netpoll_poll_dev · b249b51b
      Eric W. Biederman authored
      Today netpoll depends on setting NETPOLL_RX_DROP before networking
      drivers receive packets in interrupt context so that the packets can
      be dropped.  Move this setting into netpoll_poll_dev from
      poll_one_napi so that if ndo_poll_controller happens to receive
      packets we will drop the packets on the floor instead of letting the
      packets bounce through the networking stack and potentially cause problems.
      Signed-off-by: default avatar"Eric W. Biederman" <ebiederm@xmission.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b249b51b
    • David S. Miller's avatar
      Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next · e86e180b
      David S. Miller authored
      Pablo Neira Ayuso says:
      
      ====================
      Netfilter/IPVS updates for net-next
      
      The following patchset contains Netfilter/IPVS updates for net-next,
      most relevantly they are:
      
      * cleanup to remove double semicolon from stephen hemminger.
      
      * calm down sparse warning in xt_ipcomp, from Fan Du.
      
      * nf_ct_labels support for nf_tables, from Florian Westphal.
      
      * new macros to simplify rcu dereferences in the scope of nfnetlink
        and nf_tables, from Patrick McHardy.
      
      * Accept queue and drop (including reason for drop) to verdict
        parsing in nf_tables, also from Patrick.
      
      * Remove unused random seed initialization in nfnetlink_log, from
        Florian Westphal.
      
      * Allow to attach user-specific information to nf_tables rules, useful
        to attach user comments to rule, from me.
      
      * Return errors in ipset according to the manpage documentation, from
        Jozsef Kadlecsik.
      
      * Fix coccinelle warnings related to incorrect bool type usage for ipset,
        from Fengguang Wu.
      
      * Add hash:ip,mark set type to ipset, from Vytas Dauksa.
      
      * Fix message for each spotted by ipset for each netns that is created,
        from Ilia Mirkin.
      
      * Add forceadd option to ipset, which evicts a random entry from the set
        if it becomes full, from Josh Hunt.
      
      * Minor IPVS cleanups and fixes from Andi Kleen and Tingwei Liu.
      
      * Improve conntrack scalability by removing a central spinlock, original
        work from Eric Dumazet. Jesper Dangaard Brouer took them over to address
        remaining issues. Several patches to prepare this change come in first
        place.
      
      * Rework nft_hash to resolve bugs (leaking chain, missing rcu synchronization
        on element removal, etc. from Patrick McHardy.
      
      * Restore context in the rule deletion path, as we now release rule objects
        synchronously, from Patrick McHardy. This gets back event notification for
        anonymous sets.
      
      * Fix NAT family validation in nft_nat, also from Patrick.
      
      * Improve scalability of xt_connlimit by using an array of spinlocks and
        by introducing a rb-tree of hashtables for faster lookup of accounted
        objects per network. This patch was preceded by several patches and
        refactorizations to accomodate this change including the use of kmem_cache,
        from Florian Westphal.
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e86e180b
    • Florian Westphal's avatar
      netfilter: connlimit: use rbtree for per-host conntrack obj storage · 7d084877
      Florian Westphal authored
      With current match design every invocation of the connlimit_match
      function means we have to perform (number_of_conntracks % 256) lookups
      in the conntrack table [ to perform GC/delete stale entries ].
      This is also the reason why ____nf_conntrack_find() in perf top has
      > 20% cpu time per core.
      
      This patch changes the storage to rbtree which cuts down the number of
      ct objects that need testing.
      
      When looking up a new tuple, we only test the connections of the host
      objects we visit while searching for the wanted host/network (or
      the leaf we need to insert at).
      
      The slot count is reduced to 32.  Increasing slot count doesn't
      speed up things much because of rbtree nature.
      
      before patch (50kpps rx, 10kpps tx):
      +  20.95%  ksoftirqd/0  [nf_conntrack] [k] ____nf_conntrack_find
      +  20.50%  ksoftirqd/1  [nf_conntrack] [k] ____nf_conntrack_find
      +  20.27%  ksoftirqd/2  [nf_conntrack] [k] ____nf_conntrack_find
      +   5.76%  ksoftirqd/1  [nf_conntrack] [k] hash_conntrack_raw
      +   5.39%  ksoftirqd/2  [nf_conntrack] [k] hash_conntrack_raw
      +   5.35%  ksoftirqd/0  [nf_conntrack] [k] hash_conntrack_raw
      
      after (90kpps, 51kpps tx):
      +  17.24%       swapper  [nf_conntrack]    [k] ____nf_conntrack_find
      +   6.60%   ksoftirqd/2  [nf_conntrack]    [k] ____nf_conntrack_find
      +   2.73%       swapper  [nf_conntrack]    [k] hash_conntrack_raw
      +   2.36%       swapper  [xt_connlimit]    [k] count_tree
      
      Obvious disadvantages to previous version are the increase in code
      complexity and the increased memory cost.
      
      Partially based on Eric Dumazets fq scheduler.
      Reviewed-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      7d084877
    • Florian Westphal's avatar
      netfilter: connlimit: make same_source_net signed · 50e0e9b1
      Florian Westphal authored
      currently returns 1 if they're the same.  Make it work like mem/strcmp
      so it can be used as rbtree search function.
      Reviewed-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      50e0e9b1
    • Florian Westphal's avatar
      netfilter: connlimit: use keyed locks · 1442e750
      Florian Westphal authored
      connlimit currently suffers from spinlock contention, example for
      4-core system with rps enabled:
      
      +  20.84%   ksoftirqd/2  [kernel.kallsyms] [k] _raw_spin_lock_bh
      +  20.76%   ksoftirqd/1  [kernel.kallsyms] [k] _raw_spin_lock_bh
      +  20.42%   ksoftirqd/0  [kernel.kallsyms] [k] _raw_spin_lock_bh
      +   6.07%   ksoftirqd/2  [nf_conntrack]    [k] ____nf_conntrack_find
      +   6.07%   ksoftirqd/1  [nf_conntrack]    [k] ____nf_conntrack_find
      +   5.97%   ksoftirqd/0  [nf_conntrack]    [k] ____nf_conntrack_find
      +   2.47%   ksoftirqd/2  [nf_conntrack]    [k] hash_conntrack_raw
      +   2.45%   ksoftirqd/0  [nf_conntrack]    [k] hash_conntrack_raw
      +   2.44%   ksoftirqd/1  [nf_conntrack]    [k] hash_conntrack_raw
      
      May allow parallel lookup/insert/delete if the entry is hashed to
      another slot.  With patch:
      
      +  20.95%  ksoftirqd/0  [nf_conntrack] [k] ____nf_conntrack_find
      +  20.50%  ksoftirqd/1  [nf_conntrack] [k] ____nf_conntrack_find
      +  20.27%  ksoftirqd/2  [nf_conntrack] [k] ____nf_conntrack_find
      +   5.76%  ksoftirqd/1  [nf_conntrack] [k] hash_conntrack_raw
      +   5.39%  ksoftirqd/2  [nf_conntrack] [k] hash_conntrack_raw
      +   5.35%  ksoftirqd/0  [nf_conntrack] [k] hash_conntrack_raw
      +   2.00%  ksoftirqd/1  [kernel.kallsyms] [k] __rcu_read_unlock
      
      Improved rx processing rate from ~35kpps to ~50 kpps.
      Reviewed-by: default avatarJesper Dangaard Brouer <brouer@redhat.com>
      Signed-off-by: default avatarFlorian Westphal <fw@strlen.de>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      1442e750
  2. 15 Mar, 2014 25 commits