1. 21 Jul, 2015 21 commits
  2. 20 Jul, 2015 19 commits
    • Alexei Starovoitov's avatar
      test_bpf: add bpf_skb_vlan_push/pop() tests · 4d9c5c53
      Alexei Starovoitov authored
      improve accuracy of timing in test_bpf and add two stress tests:
      - {skb->data[0], get_smp_processor_id} repeated 2k times
      - {skb->data[0], vlan_push} x 68 followed by {skb->data[0], vlan_pop} x 68
      
      1st test is useful to test performance of JIT implementation of BPF_LD_ABS
      together with BPF_CALL instructions.
      2nd test is stressing skb_vlan_push/pop logic together with skb->data access
      via BPF_LD_ABS insn which checks that re-caching of skb->data is done correctly.
      
      In order to call bpf_skb_vlan_push() from test_bpf.ko have to add
      three export_symbol_gpl.
      Signed-off-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4d9c5c53
    • Alexei Starovoitov's avatar
      bpf: introduce bpf_skb_vlan_push/pop() helpers · 4e10df9a
      Alexei Starovoitov authored
      Allow eBPF programs attached to TC qdiscs call skb_vlan_push/pop via
      helper functions. These functions may change skb->data/hlen which are
      cached by some JITs to improve performance of ld_abs/ld_ind instructions.
      Therefore JITs need to recognize bpf_skb_vlan_push/pop() calls,
      re-compute header len and re-cache skb->data/hlen back into cpu registers.
      Note, skb->data/hlen are not directly accessible from the programs,
      so any changes to skb->data done either by these helpers or by other
      TC actions are safe.
      
      eBPF JIT supported by three architectures:
      - arm64 JIT is using bpf_load_pointer() without caching, so it's ok as-is.
      - x64 JIT re-caches skb->data/hlen unconditionally after vlan_push/pop calls
        (experiments showed that conditional re-caching is slower).
      - s390 JIT falls back to interpreter for now when bpf_skb_vlan_push() is present
        in the program (re-caching is tbd).
      
      These helpers allow more scalable handling of vlan from the programs.
      Instead of creating thousands of vlan netdevs on top of eth0 and attaching
      TC+ingress+bpf to all of them, the program can be attached to eth0 directly
      and manipulate vlans as necessary.
      Signed-off-by: default avatarAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4e10df9a
    • Jon Paul Maloy's avatar
      tipc: reduce locking scope during packet reception · d999297c
      Jon Paul Maloy authored
      We convert packet/message reception according to the same principle
      we have been using for message sending and timeout handling:
      
      We move the function tipc_rcv() to node.c, hence handling the initial
      packet reception at the link aggregation level. The function grabs
      the node lock, selects the receiving link, and accesses it via a new
      call tipc_link_rcv(). This function appends buffers to the input
      queue for delivery upwards, but it may also append outgoing packets
      to the xmit queue, just as we do during regular message sending. The
      latter will happen when buffers are forwarded from the link backlog,
      or when retransmission is requested.
      
      Upon return of this function, and after having released the node lock,
      tipc_rcv() delivers/tranmsits the contents of those queues, but it may
      also perform actions such as link activation or reset, as indicated by
      the return flags from the link.
      
      This reduces the number of cpu cycles spent inside the node spinlock,
      and reduces contention on that lock.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d999297c
    • Jon Paul Maloy's avatar
      tipc: introduce node contact FSM · 1a20cc25
      Jon Paul Maloy authored
      The logics for determining when a node is permitted to establish
      and maintain contact with its peer node becomes non-trivial in the
      presence of multiple parallel links that may come and go independently.
      
      A known failure scenario is that one endpoint registers both its links
      to the peer lost, cleans up it binding table, and prepares for a table
      update once contact is re-establihed, while the other endpoint may
      see its links reset and re-established one by one, hence seeing
      no need to re-synchronize the binding table. To avoid this, a node
      must not allow re-establishing contact until it has confirmation that
      even the peer has lost both links.
      
      Currently, the mechanism for handling this consists of setting and
      resetting two state flags from different locations in the code. This
      solution is hard to understand and maintain. A closer analysis even
      reveals that it is not completely safe.
      
      In this commit we do instead introduce an FSM that keeps track of
      the conditions for when the node can establish and maintain links.
      It has six states and four events, and is strictly based on explicit
      knowledge about the own node's and the peer node's contact states.
      Only events leading to state change are shown as edges in the figure
      below.
      
                                   +--------------+
                                   | SELF_UP/     |
                 +---------------->| PEER_COMING  |-----------------+
          SELF_  |                 +--------------+                 |PEER_
          ESTBL_ |                        |                         |ESTBL_
          CONTACT|      SELF_LOST_CONTACT |                         |CONTACT
                 |                        v                         |
                 |                 +--------------+                 |
                 |      PEER_      | SELF_DOWN/   |     SELF_       |
                 |      LOST_   +--| PEER_LEAVING |<--+ LOST_       v
      +-------------+   CONTACT |  +--------------+   | CONTACT  +-----------+
      | SELF_DOWN/  |<----------+                     +----------| SELF_UP/  |
      | PEER_DOWN   |<----------+                     +----------| PEER_UP   |
      +-------------+   SELF_   |  +--------------+   | PEER_    +-----------+
                 |      LOST_   +--| SELF_LEAVING/|<--+ LOST_       A
                 |      CONTACT    | PEER_DOWN    |     CONTACT     |
                 |                 +--------------+                 |
                 |                         A                        |
          PEER_  |       PEER_LOST_CONTACT |                        |SELF_
          ESTBL_ |                         |                        |ESTBL_
          CONTACT|                 +--------------+                 |CONTACT
                 +---------------->| PEER_UP/     |-----------------+
                                   | SELF_COMING  |
                                   +--------------+
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      1a20cc25
    • Jon Paul Maloy's avatar
      tipc: move link supervision timer to node level · 8a1577c9
      Jon Paul Maloy authored
      In our effort to move control of the links to the link aggregation
      layer, we move the perodic link supervision timer to struct tipc_node.
      The new timer is shared between all links belonging to the node, thus
      saving resources, while still kicking the FSM on both its pertaining
      links at each expiration.
      
      The current link timer and corresponding functions are removed.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8a1577c9
    • Jon Paul Maloy's avatar
      tipc: simplify link timer implementation · 333ef69e
      Jon Paul Maloy authored
      We create a second, simpler, link timer function, tipc_link_timeout().
      The new function  makes use of the new FSM function introduced in the
      previous commit, and just like it, takes a buffer queue as parameter.
      It returns an event bit field and potentially a link protocol packet
      to the caller.
      
      The existing timer function, link_timeout(), is still needed for a
      while, so we redesign it to become a wrapper around the new function.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      333ef69e
    • Jon Paul Maloy's avatar
      tipc: improve link FSM implementation · 6ab30f9c
      Jon Paul Maloy authored
      The link FSM implementation is currently unnecessarily complex.
      It sometimes checks for conditional state outside the FSM data
      before deciding next state, and often performs actions directly
      inside the FSM logics.
      
      In this commit, we create a second, simpler FSM implementation,
      that as far as possible acts only on states and events that it is
      strictly defined for, and postpone any actions until it is finished
      with its decisions. It also returns an event flag field and an a
      buffer queue which may potentially contain a protocol message to
      be sent by the caller.
      
      Unfortunately, we cannot yet make the FSM "clean", in the sense
      that its decisions are only based on FSM state and event, and that
      state changes happen only here. That will have to wait until the
      activate/reset logics has been cleaned up in a future commit.
      
      We also rename the link states as follows:
      
      WORKING_WORKING -> TIPC_LINK_WORKING
      WORKING_UNKNOWN -> TIPC_LINK_PROBING
      RESET_UNKNOWN   -> TIPC_LINK_RESETTING
      RESET_RESET     -> TIPC_LINK_ESTABLISHING
      
      The existing FSM function, link_state_event(), is still needed for
      a while, so we redesign it to make use of the new function.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6ab30f9c
    • Jon Paul Maloy's avatar
      tipc: introduce new link protocol msg create function · 426cc2b8
      Jon Paul Maloy authored
      As a preparation for later changes, we introduce a new function
      tipc_link_build_proto_msg(). Instead of actually sending the created
      protocol message, it only creates it and adds it to the head of a
      skb queue provided by the caller.
      
      Since we still need the existing function tipc_link_protocol_xmit()
      for a while, we redesign it to make use of the new function.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      426cc2b8
    • Jon Paul Maloy's avatar
      tipc: clean up definitions and usage of link flags · d3504c34
      Jon Paul Maloy authored
      The status flag LINK_STOPPED is not needed any more, since the
      mechanism for delayed deletion of links has been removed.
      Likewise, LINK_STARTED and LINK_START_EVT are unnecessary,
      because we can just as well start the link timer directly from
      inside tipc_link_create().
      
      We eliminate these flags in this commit.
      
      Instead of the above flags, we now introduce three new link modes,
      TIPC_LINK_OPEN, TIPC_LINK_BLOCKED and TIPC_LINK_TUNNEL. The values
      indicate whether, and in the case of TIPC_LINK_TUNNEL, which, messages
      the link is allowed to receive in this state. TIPC_LINK_BLOCKED also
      blocks timer-driven protocol messages to be sent out, and any change
      to the link FSM. Since the modes are mutually exclusive, we convert
      them to state values, and rename the 'flags' field in struct tipc_link
      to 'exec_mode'.
      
      Finally, we move the #defines for link FSM states and events from link.h
      into enums inside the file link.c, which is the real usage scope of
      these definitions.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d3504c34
    • Jon Paul Maloy's avatar
      tipc: make media xmit call outside node spinlock context · af9b028e
      Jon Paul Maloy authored
      Currently, message sending is performed through a deep call chain,
      where the node spinlock is grabbed and held during a significant
      part of the transmission time. This is clearly detrimental to
      overall throughput performance; it would be better if we could send
      the message after the spinlock has been released.
      
      In this commit, we do instead let the call revert on the stack after
      the buffer chain has been added to the transmission queue, whereafter
      clones of the buffers are transmitted to the device layer outside the
      spinlock scope.
      
      As a further step in our effort to separate the roles of the node
      and link entities we also move the function tipc_link_xmit() to
      node.c, and rename it to tipc_node_xmit().
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      af9b028e
    • Jon Paul Maloy's avatar
      tipc: change sk_buffer handling in tipc_link_xmit() · 22d85c79
      Jon Paul Maloy authored
      When the function tipc_link_xmit() is given a buffer list for
      transmission, it currently consumes the list both when transmission
      is successful and when it fails, except for the special case when
      it encounters link congestion.
      
      This behavior is inconsistent, and needs to be corrected if we want
      to avoid problems in later commits in this series.
      
      In this commit, we change this to let the function consume the list
      only when transmission is successful, and leave the list with the
      sender in all other cases. We also modifiy the socket code so that
      it adapts to this change, i.e., purges the list when a non-congestion
      error code is returned.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      22d85c79
    • Jon Paul Maloy's avatar
      tipc: use bearer index when looking up active links · 36e78a46
      Jon Paul Maloy authored
      struct tipc_node currently holds two arrays of link pointers; one,
      indexed by bearer identity, which contains all links irrespective of
      current state, and one two-slot array for the currently active link
      or links. The latter array contains direct pointers into the elements
      of the former. This has the effect that we cannot know the bearer id of
      a link when accessing it via the "active_links[]" array without actually
      dereferencing the pointer, something we want to avoid in some cases.
      
      In this commit, we do instead store the bearer identity in the
      "active_links" array, and use this as an index to find the right element
      in the overall link entry array. This change should be seen as a
      preparation for the later commits in this series.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      36e78a46
    • Jon Paul Maloy's avatar
      tipc: move link input queue to tipc_node · d39bbd44
      Jon Paul Maloy authored
      At present, the link input queue and the name distributor receive
      queues are fields aggregated in struct tipc_link. This is a hazard,
      because a link might be deleted while a receiving socket still keeps
      reference to one of the queues.
      
      This commit fixes this bug. However, rather than adding yet another
      reference counter to the critical data path, we move the two queues
      to safe ground inside struct tipc_node, which is already protected, and
      let the link code only handle references to the queues. This is also
      in line with planned later changes in this area.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d39bbd44
    • Jon Paul Maloy's avatar
      tipc: move link creation from neighbor discoverer to node · d3a43b90
      Jon Paul Maloy authored
      As a step towards turning links into node internal entities, we move the
      creation of links from the neighbor discovery logics to the node's link
      control logics.
      
      We also create an additional entry for the link's media address in the
      newly introduced struct tipc_link_entry, since this is where it is
      needed in the upcoming commits. The current copy in struct tipc_link
      is kept for now, but will be removed later.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      d3a43b90
    • Jon Paul Maloy's avatar
      tipc: introduce link entry structure to struct tipc_node · 9d13ec65
      Jon Paul Maloy authored
      struct 'tipc_node' currently contains two arrays for link attributes,
      one for the link pointers, and one for the usable link MTUs.
      
      We now group those into a new struct 'tipc_link_entry', and intoduce
      one single array consisting of such enties. Apart from being a cosmetic
      improvement, this is a starting point for the strict master-slave
      relation between node and link that we will introduce in the following
      commits.
      Reviewed-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarJon Maloy <jon.maloy@ericsson.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9d13ec65
    • Scott Feldman's avatar
      switchdev: add offload_fwd_mark generator helper · 1a3b2ec9
      Scott Feldman authored
      skb->offload_fwd_mark and dev->offload_fwd_mark are 32-bit and should be
      unique for device and may even be unique for a sub-set of ports within
      device, so add switchdev helper function to generate unique marks based on
      port's switch ID and group_ifindex.  group_ifindex would typically be the
      container dev's ifindex, such as the bridge's ifindex.
      
      The generator uses a global hash table to store offload_fwd_marks hashed by
      {switch ID, group_ifindex} key.
      Signed-off-by: default avatarScott Feldman <sfeldma@gmail.com>
      Acked-by: default avatarJiri Pirko <jiri@resnulli.us>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      1a3b2ec9
    • Scott Feldman's avatar
    • Scott Feldman's avatar
      net: don't reforward packets already forwarded by offload device · 0c4f691f
      Scott Feldman authored
      Just before queuing skb for xmit on port, check if skb has been marked by
      switchdev port driver as already fordwarded by device.  If so, drop skb.  A
      non-zero skb->offload_fwd_mark field is set by the switchdev port
      driver/device on ingress to indicate the skb has already been forwarded by
      the device to egress ports with matching dev->skb_mark.  The switchdev port
      driver would assign a non-zero dev->offload_skb_mark for each device port
      netdev during registration, for example.
      Signed-off-by: default avatarScott Feldman <sfeldma@gmail.com>
      Acked-by: default avatarJiri Pirko <jiri@resnulli.us>
      Acked-by: default avatarRoopa Prabhu <roopa@cumulusnetworks.com>
      Acked-by: default avatarNicolas Dichtel <nicolas.dichtel@6wind.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0c4f691f
    • Nikolay Aleksandrov's avatar
      bridge: mcast: fix br_multicast_dev_del warn when igmp snooping is not defined · a7ce45a7
      Nikolay Aleksandrov authored
      Fix:
      net/bridge/br_if.c: In function 'br_dev_delete':
      >> net/bridge/br_if.c:284:2: error: implicit declaration of function
      >> 'br_multicast_dev_del' [-Werror=implicit-function-declaration]
           br_multicast_dev_del(br);
           ^
         cc1: some warnings being treated as errors
      
      when igmp snooping is not defined.
      Signed-off-by: default avatarNikolay Aleksandrov <nikolay@cumulusnetworks.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      a7ce45a7