1. 03 Sep, 2012 1 commit
    • Pablo Neira Ayuso's avatar
      netfilter: xt_socket: fix compilation warnings with gcc 4.7 · 6703aa74
      Pablo Neira Ayuso authored
      
      
      This patch fixes compilation warnings in xt_socket with gcc-4.7.
      
      In file included from net/netfilter/xt_socket.c:22:0:
      net/netfilter/xt_socket.c: In function ‘socket_mt6_v1’:
      include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:265:16: note: ‘sport’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:265:9: note: ‘dport’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:264:27: note: ‘saddr’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:264:19: note: ‘daddr’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      net/netfilter/xt_socket.c: In function ‘socket_match.isra.4’:
      include/net/netfilter/nf_tproxy_core.h:75:2: warning: ‘protocol’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:113:5: note: ‘protocol’ was declared here
      In file included from include/net/tcp.h:37:0,
                       from net/netfilter/xt_socket.c:17:
      include/net/inet_hashtables.h:356:45: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:112:16: note: ‘sport’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:106:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:112:9: note: ‘dport’ was declared here
      In file included from include/net/tcp.h:37:0,
                       from net/netfilter/xt_socket.c:17:
      include/net/inet_hashtables.h:356:15: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:111:16: note: ‘saddr’ was declared here
      In file included from include/net/tcp.h:37:0,
                       from net/netfilter/xt_socket.c:17:
      include/net/inet_hashtables.h:356:15: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:111:9: note: ‘daddr’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      net/netfilter/xt_socket.c: In function ‘socket_mt6_v1’:
      include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘sport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:268:16: note: ‘sport’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:175:23: warning: ‘dport’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:268:9: note: ‘dport’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘saddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:267:27: note: ‘saddr’ was declared here
      In file included from net/netfilter/xt_socket.c:22:0:
      include/net/netfilter/nf_tproxy_core.h:175:6: warning: ‘daddr’ may be used uninitialized in this function [-Wmaybe-uninitialized]
      net/netfilter/xt_socket.c:267:19: note: ‘daddr’ was declared here
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      6703aa74
  2. 29 Aug, 2012 18 commits
  3. 26 Aug, 2012 1 commit
  4. 22 Aug, 2012 13 commits
    • Pavel Emelyanov's avatar
      packet: Protect packet sk list with mutex (v2) · 0fa7fa98
      Pavel Emelyanov authored
      Change since v1:
      
      * Fixed inuse counters access spotted by Eric
      
      In patch eea68e2f
      
       (packet: Report socket mclist info via diag module) I've
      introduced a "scheduling in atomic" problem in packet diag module -- the
      socket list is traversed under rcu_read_lock() while performed under it sk
      mclist access requires rtnl lock (i.e. -- mutex) to be taken.
      
      [152363.820563] BUG: scheduling while atomic: crtools/12517/0x10000002
      [152363.820573] 4 locks held by crtools/12517:
      [152363.820581]  #0:  (sock_diag_mutex){+.+.+.}, at: [<ffffffff81a2dcb5>] sock_diag_rcv+0x1f/0x3e
      [152363.820613]  #1:  (sock_diag_table_mutex){+.+.+.}, at: [<ffffffff81a2de70>] sock_diag_rcv_msg+0xdb/0x11a
      [152363.820644]  #2:  (nlk->cb_mutex){+.+.+.}, at: [<ffffffff81a67d01>] netlink_dump+0x23/0x1ab
      [152363.820693]  #3:  (rcu_read_lock){.+.+..}, at: [<ffffffff81b6a049>] packet_diag_dump+0x0/0x1af
      
      Similar thing was then re-introduced by further packet diag patches (fanount
      mutex and pgvec mutex for rings) :(
      
      Apart from being terribly sorry for the above, I propose to change the packet
      sk list protection from spinlock to mutex. This lock currently protects two
      modifications:
      
      * sklist
      * prot inuse counters
      
      The sklist modifications can be just reprotected with mutex since they already
      occur in a sleeping context. The inuse counters modifications are trickier -- the
      __this_cpu_-s are used inside, thus requiring the caller to handle the potential
      issues with contexts himself. Since packet sockets' counters are modified in two
      places only (packet_create and packet_release) we only need to protect the context
      from being preempted. BH disabling is not required in this case.
      Signed-off-by: default avatarPavel Emelyanov <xemul@parallels.com>
      Acked-by: default avatarEric Dumazet <edumazet@google.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0fa7fa98
    • Allan, Bruce W's avatar
      mdio: translation of MMD EEE registers to/from ethtool settings · b32607dd
      Allan, Bruce W authored
      
      
      The helper functions which translate IEEE MDIO Manageable Device (MMD)
      Energy-Efficient Ethernet (EEE) registers 3.20, 7.60 and 7.61 to and from
      the comparable ethtool supported/advertised settings will be needed by
      drivers other than those in PHYLIB (e.g. e1000e in a follow-on patch).
      
      In the same fashion as similar translation functions in linux/mii.h, move
      these functions from the PHYLIB core to the linux/mdio.h header file so the
      code will not have to be duplicated in each driver needing MMD-to-ethtool
      (and vice-versa) translations.  The function and some variable names have
      been renamed to be more descriptive.
      
      Not tested on the only hardware that currently calls the related functions,
      stmmac, because I don't have access to any.  Has been compile tested and
      the translations have been tested on a locally modified version of e1000e.
      Signed-off-by: default avatarBruce Allan <bruce.w.allan@intel.com>
      Cc: Giuseppe Cavallaro <peppe.cavallaro@st.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b32607dd
    • danborkmann@iogearbox.net's avatar
      af_packet: use define instead of constant · 9e67030a
      danborkmann@iogearbox.net authored
      
      
      Instead of using a hard-coded value for the status variable, it would make
      the code more readable to use its destined define from linux/if_packet.h.
      
      Signed-off-by: daniel.borkmann@tik.ee.ethz.ch
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      9e67030a
    • Ying Xue's avatar
      rds: Don't disable BH on BH context · bfdc587c
      Ying Xue authored
      
      
      Since we have already in BH context when *_write_space(),
      *_data_ready() as well as *_state_change() are called, it's
      unnecessary to disable BH.
      Signed-off-by: default avatarYing Xue <ying.xue@windriver.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bfdc587c
    • John Eaglesham's avatar
      bonding: support for IPv6 transmit hashing · 6b923cb7
      John Eaglesham authored
      
      
      Currently the "bonding" driver does not support load balancing outgoing
      traffic in LACP mode for IPv6 traffic. IPv4 (and TCP or UDP over IPv4)
      are currently supported; this patch adds transmit hashing for IPv6 (and
      TCP or UDP over IPv6), bringing IPv6 up to par with IPv4 support in the
      bonding driver. In addition, bounds checking has been added to all
      transmit hashing functions.
      
      The algorithm chosen (xor'ing the bottom three quads of the source and
      destination addresses together, then xor'ing each byte of that result into
      the bottom byte, finally xor'ing with the last bytes of the MAC addresses)
      was selected after testing almost 400,000 unique IPv6 addresses harvested
      from server logs. This algorithm had the most even distribution for both
      big- and little-endian architectures while still using few instructions. Its
      behavior also attempts to closely match that of the IPv4 algorithm.
      
      The IPv6 flow label was intentionally not included in the hash as it appears
      to be unset in the vast majority of IPv6 traffic sampled, and the current
      algorithm not using the flow label already offers a very even distribution.
      
      Fragmented IPv6 packets are handled the same way as fragmented IPv4 packets,
      ie, they are not balanced based on layer 4 information. Additionally,
      IPv6 packets with intermediate headers are not balanced based on layer
      4 information. In practice these intermediate headers are not common and
      this should not cause any problems, and the alternative (a packet-parsing
      loop and look-up table) seemed slow and complicated for little gain.
      Tested-by: default avatarJohn Eaglesham <linux@8192.net>
      Signed-off-by: default avatarJohn Eaglesham <linux@8192.net>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      6b923cb7
    • Eric Dumazet's avatar
      ipv6: gre: fix ip6gre_err() · b87fb39e
      Eric Dumazet authored
      
      
      ip6gre_err() miscomputes grehlen (sizeof(ipv6h) is 4 or 8,
      not 40 as expected), and should take into account 'offset' parameter.
      
      Also uses pskb_may_pull() to cope with some fragged skbs
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Dmitry Kozlov <xeb@mail.ru>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b87fb39e
    • Eric Dumazet's avatar
      xfrm: fix RCU bugs · ef8531b6
      Eric Dumazet authored
      This patch reverts commit 56892261 (xfrm: Use rcu_dereference_bh to
      deference pointer protected by rcu_read_lock_bh), and fixes bugs
      introduced in commit 418a99ac
      
       ( Replace rwlock on xfrm_policy_afinfo
      with rcu )
      
      1) We properly use RCU variant in this file, not a mix of RCU/RCU_BH
      
      2) We must defer some writes after the synchronize_rcu() call or a reader
       can crash dereferencing NULL pointer.
      
      3) Now we use the xfrm_policy_afinfo_lock spinlock only from process
      context, we no longer need to block BH in xfrm_policy_register_afinfo()
      and xfrm_policy_unregister_afinfo()
      
      4) Can use RCU_INIT_POINTER() instead of rcu_assign_pointer() in
      xfrm_policy_unregister_afinfo()
      
      5) Remove a forward inline declaration (xfrm_policy_put_afinfo()),
        and also move xfrm_policy_get_afinfo() declaration.
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Fan Du <fan.du@windriver.com>
      Cc: Priyanka Jain <Priyanka.Jain@freescale.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      ef8531b6
    • Eric Dumazet's avatar
      net: remove delay at device dismantle · 0115e8e3
      Eric Dumazet authored
      
      
      I noticed extra one second delay in device dismantle, tracked down to
      a call to dst_dev_event() while some call_rcu() are still in RCU queues.
      
      These call_rcu() were posted by rt_free(struct rtable *rt) calls.
      
      We then wait a little (but one second) in netdev_wait_allrefs() before
      kicking again NETDEV_UNREGISTER.
      
      As the call_rcu() are now completed, dst_dev_event() can do the needed
      device swap on busy dst.
      
      To solve this problem, add a new NETDEV_UNREGISTER_FINAL, called
      after a rcu_barrier(), but outside of RTNL lock.
      
      Use NETDEV_UNREGISTER_FINAL with care !
      
      Change dst_dev_event() handler to react to NETDEV_UNREGISTER_FINAL
      
      Also remove NETDEV_UNREGISTER_BATCH, as its not used anymore after
      IP cache removal.
      
      With help from Gao feng
      Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
      Cc: Tom Herbert <therbert@google.com>
      Cc: Mahesh Bandewar <maheshb@google.com>
      Cc: "Eric W. Biederman" <ebiederm@xmission.com>
      Cc: Gao feng <gaofeng@cn.fujitsu.com>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      0115e8e3
    • David S. Miller's avatar
      Merge git://1984.lsi.us.es/nf-next · bf277b0c
      David S. Miller authored
      
      
      Pablo Neira Ayuso says:
      
      ====================
      This is the first batch of Netfilter and IPVS updates for your
      net-next tree. Mostly cleanups for the Netfilter side. They are:
      
      * Remove unnecessary RTNL locking now that we have support
        for namespace in nf_conntrack, from Patrick McHardy.
      
      * Cleanup to eliminate unnecessary goto in the initialization
        path of several Netfilter tables, from Jean Sacren.
      
      * Another cleanup from Wu Fengguang, this time to PTR_RET instead
        of if IS_ERR then return PTR_ERR.
      
      * Use list_for_each_entry_continue_rcu in nf_iterate, from
        Michael Wang.
      
      * Add pmtu_disc sysctl option to disable PMTU in their tunneling
        transmitter, from Julian Anastasov.
      
      * Generalize application protocol registration in IPVS and modify
        IPVS FTP helper to use it, from Julian Anastasov.
      
      * update Kconfig. The IPVS FTP helper depends on the Netfilter FTP
        helper for NAT support, from Julian Anastasov.
      
      * Add logic to update PMTU for IPIP packets in IPVS, again
        from Julian Anastasov.
      
      * A couple of sparse warning fixes for IPVS and Netfilter from
        Claudiu Ghioc and Patrick McHardy respectively.
      
      Patrick's IPv6 NAT changes will follow after this batch, I need
      to flush this batch first before refreshing my tree.
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bf277b0c
    • David S. Miller's avatar
      Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/net-next · bba6ec7e
      David S. Miller authored
      
      
      Jeff Kirsher says:
      
      ====================
      This series contains updates to ethtool.h, e1000, e1000e, and igb to
      implement MDI/MDIx control.
      ====================
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bba6ec7e
    • David S. Miller's avatar
    • Jean Sacren's avatar
      netfilter: remove unnecessary goto statement for error recovery · 90efbed1
      Jean Sacren authored
      
      
      Usually it's a good practice to use goto statement for error recovery
      when initializing the module. This approach could be an overkill if:
      
       1) there is only one fail case;
       2) success and failure use the same return statement.
      
      For a cleaner approach, remove the unnecessary goto statement and
      directly implement error recovery.
      Signed-off-by: default avatarJean Sacren <sakiwit@gmail.com>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      90efbed1
    • Michael Wang's avatar
      netfilter: replace list_for_each_continue_rcu with new interface · 6705e867
      Michael Wang authored
      
      
      This patch replaces list_for_each_continue_rcu() with
      list_for_each_entry_continue_rcu() to allow removing
      list_for_each_continue_rcu().
      Signed-off-by: default avatarMichael Wang <wangyun@linux.vnet.ibm.com>
      Reviewed-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
      Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
      6705e867
  5. 21 Aug, 2012 7 commits
    • Linus Torvalds's avatar
      Merge branch 'akpm' (Andrew's patch-bomb) · 23dcfa61
      Linus Torvalds authored
      Merge fixes from Andrew Morton.
      
      Random drivers and some VM fixes.
      
      * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (17 commits)
        mm: compaction: Abort async compaction if locks are contended or taking too long
        mm: have order > 0 compaction start near a pageblock with free pages
        rapidio/tsi721: fix unused variable compiler warning
        rapidio/tsi721: fix inbound doorbell interrupt handling
        drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode
        mm: correct page->pfmemalloc to fix deactivate_slab regression
        drivers/rtc/rtc-pcf2123.c: initialize dynamic sysfs attributes
        mm/compaction.c: fix deferring compaction mistake
        drivers/misc/sgi-xp/xpc_uv.c: SGI XPC fails to load when cpu 0 is out of IRQ resources
        string: do not export memweight() to userspace
        hugetlb: update hugetlbpage.txt
        checkpatch: add control statement test to SINGLE_STATEMENT_DO_WHILE_MACRO
        mm: hugetlbfs: correctly populate shared pmd
        cciss: fix incorrect scsi status reporting
        Documentation: update mount option in filesystem/vfat.txt
        mm: change nr_ptes BUG_ON to WARN_ON
        cs5535-clockevt: typo, it's MFGPT, not MFPGT
      23dcfa61
    • Linus Torvalds's avatar
      Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media · a484147a
      Linus Torvalds authored
      Pull media fixes from Mauro Carvalho Chehab:
       "For bug fixes, at soc_camera, si470x, uvcvideo, iguanaworks IR driver,
        radio_shark Kbuild fixes, and at the V4L2 core (radio fixes)."
      
      * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
        [media] media: soc_camera: don't clear pix->sizeimage in JPEG mode
        [media] media: mx2_camera: Fix clock handling for i.MX27
        [media] video: mx2_camera: Use clk_prepare_enable/clk_disable_unprepare
        [media] video: mx1_camera: Use clk_prepare_enable/clk_disable_unprepare
        [media] media: mx3_camera: buf_init() add buffer state check
        [media] radio-shark2: Only compile led support when CONFIG_LED_CLASS is set
        [media] radio-shark: Only compile led support when CONFIG_LED_CLASS is set
        [media] radio-shark*: Call cancel_work_sync from disconnect rather then release
        [media] radio-shark*: Remove work-around for dangling pointer in usb intfdata
        [media] Add USB dependency for IguanaWorks USB IR Transceiver
        [media] Add missing logging for rangelow/high of hwseek
        [media] VIDIOC_ENUM_FREQ_BANDS fix
        [media] mem2mem_testdev: fix querycap regression
        [media] si470x: v4l2-compliance fixes
        [media] DocBook: Remove a spurious character
        [media] uvcvideo: Reset the bytesused field when recycling an erroneous buffer
      a484147a
    • Linus Torvalds's avatar
      Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net · 8f8ba75e
      Linus Torvalds authored
      Pull networking update from David Miller:
       "A couple weeks of bug fixing in there.  The largest chunk is all the
        broken crap Amerigo Wang found in the netpoll layer."
      
       1) netpoll and it's users has several serious bugs:
          a) uses GFP_KERNEL with locks held
          b) interfaces requiring interrupts disabled are called with them
             enabled
          c) and vice versa
          d) VLAN tag demuxing, as per all other RX packet input paths, is not
             applied
      
          All from Amerigo Wang.
      
       2) Hopefully cure the ipv4 mapped ipv6 address TCP early demux bugs for
          good, from Neal Cardwell.
      
       3) Unlike AF_UNIX, AF_PACKET sockets don't set a default credentials
          when the user doesn't specify one explicitly during sendmsg().
          Instead we attach an empty (zero) SCM credential block which is
          definitely not what we want.  Fix from Eric Dumazet.
      
       4) IPv6 illegally invokes netdevice notifiers with RCU lock held, fix
          from Ben Hutchings.
      
       5) inet_csk_route_child_sock() checks wrong inet options pointer, fix
          from Christoph Paasch.
      
       6) When AF_PACKET is used for transmit, packet loopback doesn't behave
          properly when a socket fanout is enabled, from Eric Leblond.
      
       7) On bluetooth l2cap channel create failure, we leak the socket, from
          Jaganath Kanakkassery.
      
       8) Fix all the netprio file handling bugs found by Al Viro, from John
          Fastabend.
      
       9) Several error return and NULL deref bug fixes in networking drivers
          from Julia Lawall.
      
      10) A large smattering of struct padding et al.  kernel memory leaks to
          userspace found of Mathias Krause.
      
      11) Conntrack expections in netfilter can access an uninitialized timer,
          fix from Pablo Neira Ayuso.
      
      12) Several netfilter SIP tracker bug fixes from Patrick McHardy.
      
      13) IPSEC ipv6 routes are not initialized correctly all the time,
          resulting in an OOPS in inet_putpeer().  Also from Patrick McHardy.
      
      14) Bridging does rcu_dereference() outside of RCU protected area, from
          Stephen Hemminger.
      
      15) Fix routing cache removal performance regression when looking up
          output routes that have a local destination.  From Zheng Yan.
      
      * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (87 commits)
        af_netlink: force credentials passing [CVE-2012-3520]
        ipv4: fix ip header ident selection in __ip_make_skb()
        ipv4: Use newinet->inet_opt in inet_csk_route_child_sock()
        tcp: fix possible socket refcount problem
        net: tcp: move sk_rx_dst_set call after tcp_create_openreq_child()
        net/core/dev.c: fix kernel-doc warning
        netconsole: remove a redundant netconsole_target_put()
        net: ipv6: fix oops in inet_putpeer()
        net/stmmac: fix issue of clk_get for Loongson1B.
        caif: Do not dereference NULL in chnl_recv_cb()
        af_packet: don't emit packet on orig fanout group
        drivers/net/irda: fix error return code
        drivers/net/wan/dscc4.c: fix error return code
        drivers/net/wimax/i2400m/fw.c: fix error return code
        smsc75xx: add missing entry to MAINTAINERS
        net: qmi_wwan: new devices: UML290 and K5006-Z
        net: sh_eth: Add eth support for R8A7779 device
        netdev/phy: skip disabled mdio-mux nodes
        dt: introduce for_each_available_child_of_node, of_get_next_available_child
        net: netprio: fix cgrp create and write priomap race
        ...
      8f8ba75e
    • Mel Gorman's avatar
      mm: compaction: Abort async compaction if locks are contended or taking too long · c67fe375
      Mel Gorman authored
      Jim Schutt reported a problem that pointed at compaction contending
      heavily on locks.  The workload is straight-forward and in his own words;
      
      	The systems in question have 24 SAS drives spread across 3 HBAs,
      	running 24 Ceph OSD instances, one per drive.  FWIW these servers
      	are dual-socket Intel 5675 Xeons w/48 GB memory.  I've got ~160
      	Ceph Linux clients doing dd simultaneously to a Ceph file system
      	backed by 12 of these servers.
      
      Early in the test everything looks fine
      
        procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
         r  b       swpd       free       buff      cache   si   so    bi    bo   in   cs  us sy  id wa st
        31 15          0     287216        576   38606628    0    0     2  1158    2   14   1  3  95  0  0
        27 15          0     225288        576   38583384    0    0    18 2222016 203357 134876  11 56  17 15  0
        28 17          0     219256        576   38544736    0    0    11 2305932 203141 146296  11 49  23 17  0
         6 18          0     215596        576   38552872    0    0     7 2363207 215264 166502  12 45  22 20  0
        22 18          0     226984        576   38596404    0    0     3 2445741 223114 179527  12 43  23 22  0
      
      and then it goes to pot
      
        procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
         r  b       swpd       free       buff      cache   si   so    bi    bo   in   cs  us sy  id wa st
        163  8          0     464308        576   36791368    0    0    11 22210  866  536   3 13  79  4  0
        207 14          0     917752        576   36181928    0    0   712 1345376 134598 47367   7 90   1  2  0
        123 12          0     685516        576   36296148    0    0   429 1386615 158494 60077   8 84   5  3  0
        123 12          0     598572        576   36333728    0    0  1107 1233281 147542 62351   7 84   5  4  0
        622  7          0     660768        576   36118264    0    0   557 1345548 151394 59353   7 85   4  3  0
        223 11          0     283960        576   36463868    0    0    46 1107160 121846 33006   6 93   1  1  0
      
      Note that system CPU usage is very high blocks being written out has
      dropped by 42%. He analysed this with perf and found
      
        perf record -g -a sleep 10
        perf report --sort symbol --call-graph fractal,5
          34.63%  [k] _raw_spin_lock_irqsave
                  |
                  |--97.30%-- isolate_freepages
                  |          compaction_alloc
                  |          unmap_and_move
                  |          migrate_pages
                  |          compact_zone
                  |          compact_zone_order
                  |          try_to_compact_pages
                  |          __alloc_pages_direct_compact
                  |          __alloc_pages_slowpath
                  |          __alloc_pages_nodemask
                  |          alloc_pages_vma
                  |          do_huge_pmd_anonymous_page
                  |          handle_mm_fault
                  |          do_page_fault
                  |          page_fault
                  |          |
                  |          |--87.39%-- skb_copy_datagram_iovec
                  |          |          tcp_recvmsg
                  |          |          inet_recvmsg
                  |          |          sock_recvmsg
                  |          |          sys_recvfrom
                  |          |          system_call
                  |          |          __recv
                  |          |          |
                  |          |           --100.00%-- (nil)
                  |          |
                  |           --12.61%-- memcpy
                   --2.70%-- [...]
      
      There was other data but primarily it is all showing that compaction is
      contended heavily on the zone->lock and zone->lru_lock.
      
      commit [b2eef8c0
      
      : mm: compaction: minimise the time IRQs are disabled
      while isolating pages for migration] noted that it was possible for
      migration to hold the lru_lock for an excessive amount of time. Very
      broadly speaking this patch expands the concept.
      
      This patch introduces compact_checklock_irqsave() to check if a lock
      is contended or the process needs to be scheduled. If either condition
      is true then async compaction is aborted and the caller is informed.
      The page allocator will fail a THP allocation if compaction failed due
      to contention. This patch also introduces compact_trylock_irqsave()
      which will acquire the lock only if it is not contended and the process
      does not need to schedule.
      Reported-by: default avatarJim Schutt <jaschut@sandia.gov>
      Tested-by: default avatarJim Schutt <jaschut@sandia.gov>
      Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c67fe375
    • Mel Gorman's avatar
      mm: have order > 0 compaction start near a pageblock with free pages · de74f1cc
      Mel Gorman authored
      Commit 7db8889a
      
       ("mm: have order > 0 compaction start off where it
      left") introduced a caching mechanism to reduce the amount work the free
      page scanner does in compaction.  However, it has a problem.  Consider
      two process simultaneously scanning free pages
      
      					    			C
      	Process A		M     S     			F
      			|---------------------------------------|
      	Process B		M 	FS
      
      	C is zone->compact_cached_free_pfn
      	S is cc->start_pfree_pfn
      	M is cc->migrate_pfn
      	F is cc->free_pfn
      
      In this diagram, Process A has just reached its migrate scanner, wrapped
      around and updated compact_cached_free_pfn accordingly.
      
      Simultaneously, Process B finishes isolating in a block and updates
      compact_cached_free_pfn again to the location of its free scanner.
      
      Process A moves to "end_of_zone - one_pageblock" and runs this check
      
                      if (cc->order > 0 && (!cc->wrapped ||
                                            zone->compact_cached_free_pfn >
                                            cc->start_free_pfn))
                              pfn = min(pfn, zone->compact_cached_free_pfn);
      
      compact_cached_free_pfn is above where it started so the free scanner
      skips almost the entire space it should have scanned.  When there are
      multiple processes compacting it can end in a situation where the entire
      zone is not being scanned at all.  Further, it is possible for two
      processes to ping-pong update to compact_cached_free_pfn which is just
      random.
      
      Overall, the end result wrecks allocation success rates.
      
      There is not an obvious way around this problem without introducing new
      locking and state so this patch takes a different approach.
      
      First, it gets rid of the skip logic because it's not clear that it
      matters if two free scanners happen to be in the same block but with
      racing updates it's too easy for it to skip over blocks it should not.
      
      Second, it updates compact_cached_free_pfn in a more limited set of
      circumstances.
      
      If a scanner has wrapped, it updates compact_cached_free_pfn to the end
      	of the zone. When a wrapped scanner isolates a page, it updates
      	compact_cached_free_pfn to point to the highest pageblock it
      	can isolate pages from.
      
      If a scanner has not wrapped when it has finished isolated pages it
      	checks if compact_cached_free_pfn is pointing to the end of the
      	zone. If so, the value is updated to point to the highest
      	pageblock that pages were isolated from. This value will not
      	be updated again until a free page scanner wraps and resets
      	compact_cached_free_pfn.
      
      This is not optimal and it can still race but the compact_cached_free_pfn
      will be pointing to or very near a pageblock with free pages.
      Signed-off-by: default avatarMel Gorman <mgorman@suse.de>
      Reviewed-by: default avatarRik van Riel <riel@redhat.com>
      Reviewed-by: default avatarMinchan Kim <minchan@kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      de74f1cc
    • Alexandre Bounine's avatar
      rapidio/tsi721: fix unused variable compiler warning · 9a9a9a7a
      Alexandre Bounine authored
      
      
      Fix unused variable compiler warning when built with CONFIG_RAPIDIO_DEBUG
      option off.
      
      This patch is applicable to kernel versions starting from v3.2
      Signed-off-by: default avatarAlexandre Bounine <alexandre.bounine@idt.com>
      Cc: Matt Porter <mporter@kernel.crashing.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      9a9a9a7a
    • Alexandre Bounine's avatar
      rapidio/tsi721: fix inbound doorbell interrupt handling · 3670e7e1
      Alexandre Bounine authored
      
      
      Make sure that there is no doorbell messages left behind due to disabled
      interrupts during inbound doorbell processing.
      
      The most common case for this bug is loss of rionet JOIN messages in
      systems with three or more rionet participants and MSI or MSI-X enabled.
      As result, requests for packet transfers may finish with "destination
      unreachable" error message.
      
      This patch is applicable to kernel versions starting from v3.2.
      Signed-off-by: default avatarAlexandre Bounine <alexandre.bounine@idt.com>
      Cc: Matt Porter <mporter@kernel.crashing.org>
      Cc: <stable@vger.kernel.org>
      Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
      Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      3670e7e1