1. 27 1月, 2010 1 次提交
  2. 13 10月, 2009 1 次提交
    • N
      net: Generalize socket rx gap / receive queue overflow cmsg · 3b885787
      Neil Horman 提交于
      Create a new socket level option to report number of queue overflows
      
      Recently I augmented the AF_PACKET protocol to report the number of frames lost
      on the socket receive queue between any two enqueued frames.  This value was
      exported via a SOL_PACKET level cmsg.  AFter I completed that work it was
      requested that this feature be generalized so that any datagram oriented socket
      could make use of this option.  As such I've created this patch, It creates a
      new SOL_SOCKET level option called SO_RXQ_OVFL, which when enabled exports a
      SOL_SOCKET level cmsg that reports the nubmer of times the sk_receive_queue
      overflowed between any two given frames.  It also augments the AF_PACKET
      protocol to take advantage of this new feature (as it previously did not touch
      sk->sk_drops, which this patch uses to record the overflow count).  Tested
      successfully by me.
      
      Notes:
      
      1) Unlike my previous patch, this patch simply records the sk_drops value, which
      is not a number of drops between packets, but rather a total number of drops.
      Deltas must be computed in user space.
      
      2) While this patch currently works with datagram oriented protocols, it will
      also be accepted by non-datagram oriented protocols. I'm not sure if thats
      agreeable to everyone, but my argument in favor of doing so is that, for those
      protocols which aren't applicable to this option, sk_drops will always be zero,
      and reporting no drops on a receive queue that isn't used for those
      non-participating protocols seems reasonable to me.  This also saves us having
      to code in a per-protocol opt in mechanism.
      
      3) This applies cleanly to net-next assuming that commit
      97775007 (my af packet cmsg patch) is reverted
      Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3b885787
  3. 01 10月, 2009 1 次提交
  4. 10 7月, 2009 1 次提交
    • J
      net: adding memory barrier to the poll and receive callbacks · a57de0b4
      Jiri Olsa 提交于
      Adding memory barrier after the poll_wait function, paired with
      receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper
      to wrap the memory barrier.
      
      Without the memory barrier, following race can happen.
      The race fires, when following code paths meet, and the tp->rcv_nxt
      and __add_wait_queue updates stay in CPU caches.
      
      CPU1                         CPU2
      
      sys_select                   receive packet
        ...                        ...
        __add_wait_queue           update tp->rcv_nxt
        ...                        ...
        tp->rcv_nxt check          sock_def_readable
        ...                        {
        schedule                      ...
                                      if (sk->sk_sleep && waitqueue_active(sk->sk_sleep))
                                              wake_up_interruptible(sk->sk_sleep)
                                      ...
                                   }
      
      If there was no cache the code would work ok, since the wait_queue and
      rcv_nxt are opposit to each other.
      
      Meaning that once tp->rcv_nxt is updated by CPU2, the CPU1 either already
      passed the tp->rcv_nxt check and sleeps, or will get the new value for
      tp->rcv_nxt and will return with new data mask.
      In both cases the process (CPU1) is being added to the wait queue, so the
      waitqueue_active (CPU2) call cannot miss and will wake up CPU1.
      
      The bad case is when the __add_wait_queue changes done by CPU1 stay in its
      cache, and so does the tp->rcv_nxt update on CPU2 side.  The CPU1 will then
      endup calling schedule and sleep forever if there are no more data on the
      socket.
      
      Calls to poll_wait in following modules were ommited:
      	net/bluetooth/af_bluetooth.c
      	net/irda/af_irda.c
      	net/irda/irnet/irnet_ppp.c
      	net/mac80211/rc80211_pid_debugfs.c
      	net/phonet/socket.c
      	net/rds/af_rds.c
      	net/rfkill/core.c
      	net/sunrpc/cache.c
      	net/sunrpc/rpc_pipe.c
      	net/tipc/socket.c
      Signed-off-by: NJiri Olsa <jolsa@redhat.com>
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a57de0b4
  5. 18 6月, 2009 1 次提交
  6. 18 6月, 2008 1 次提交
  7. 29 1月, 2008 1 次提交
  8. 01 11月, 2007 1 次提交
  9. 11 10月, 2007 2 次提交
    • E
      [NET]: Make socket creation namespace safe. · 1b8d7ae4
      Eric W. Biederman 提交于
      This patch passes in the namespace a new socket should be created in
      and has the socket code do the appropriate reference counting.  By
      virtue of this all socket create methods are touched.  In addition
      the socket create methods are modified so that they will fail if
      you attempt to create a socket in a non-default network namespace.
      
      Failing if we attempt to create a socket outside of the default
      network namespace ensures that as we incrementally make the network stack
      network namespace aware we will not export functionality that someone
      has not audited and made certain is network namespace safe.
      Allowing us to partially enable network namespaces before all of the
      exotic protocols are supported.
      
      Any protocol layers I have missed will fail to compile because I now
      pass an extra parameter into the socket creation code.
      
      [ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1b8d7ae4
    • S
      [ATM]: Replace DPRINTK() with pr_debug(). · 52240062
      Stephen Hemminger 提交于
      Get rid of using DPRINTK macro in ATM and use pr_debug (in kernel.h).
      Using the standard macro is cleaner and forces code to check for bad arguments
      and formatting.
      
      Fixes from Thomas Graf.
      Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      52240062
  10. 11 2月, 2007 1 次提交
  11. 09 2月, 2007 1 次提交
  12. 01 7月, 2006 1 次提交
  13. 30 6月, 2006 1 次提交
  14. 21 3月, 2006 1 次提交
  15. 30 11月, 2005 4 次提交
  16. 04 10月, 2005 1 次提交
    • E
      [INET]: speedup inet (tcp/dccp) lookups · 81c3d547
      Eric Dumazet 提交于
      Arnaldo and I agreed it could be applied now, because I have other
      pending patches depending on this one (Thank you Arnaldo)
      
      (The other important patch moves skc_refcnt in a separate cache line,
      so that the SMP/NUMA performance doesnt suffer from cache line ping pongs)
      
      1) First some performance data :
      --------------------------------
      
      tcp_v4_rcv() wastes a *lot* of time in __inet_lookup_established()
      
      The most time critical code is :
      
      sk_for_each(sk, node, &head->chain) {
           if (INET_MATCH(sk, acookie, saddr, daddr, ports, dif))
               goto hit; /* You sunk my battleship! */
      }
      
      The sk_for_each() does use prefetch() hints but only the begining of
      "struct sock" is prefetched.
      
      As INET_MATCH first comparison uses inet_sk(__sk)->daddr, wich is far
      away from the begining of "struct sock", it has to bring into CPU
      cache cold cache line. Each iteration has to use at least 2 cache
      lines.
      
      This can be problematic if some chains are very long.
      
      2) The goal
      -----------
      
      The idea I had is to change things so that INET_MATCH() may return
      FALSE in 99% of cases only using the data already in the CPU cache,
      using one cache line per iteration.
      
      3) Description of the patch
      ---------------------------
      
      Adds a new 'unsigned int skc_hash' field in 'struct sock_common',
      filling a 32 bits hole on 64 bits platform.
      
      struct sock_common {
      	unsigned short		skc_family;
      	volatile unsigned char	skc_state;
      	unsigned char		skc_reuse;
      	int			skc_bound_dev_if;
      	struct hlist_node	skc_node;
      	struct hlist_node	skc_bind_node;
      	atomic_t		skc_refcnt;
      +	unsigned int		skc_hash;
      	struct proto		*skc_prot;
      };
      
      Store in this 32 bits field the full hash, not masked by (ehash_size -
      1) Using this full hash as the first comparison done in INET_MATCH
      permits us immediatly skip the element without touching a second cache
      line in case of a miss.
      
      Suppress the sk_hashent/tw_hashent fields since skc_hash (aliased to
      sk_hash and tw_hash) already contains the slot number if we mask with
      (ehash_size - 1)
      
      File include/net/inet_hashtables.h
      
      64 bits platforms :
      #define INET_MATCH(__sk, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
           (((__sk)->sk_hash == (__hash))
           ((*((__u64 *)&(inet_sk(__sk)->daddr)))== (__cookie))   &&  \
           ((*((__u32 *)&(inet_sk(__sk)->dport))) == (__ports))   &&  \
           (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
      
      32bits platforms:
      #define TCP_IPV4_MATCH(__sk, __hash, __cookie, __saddr, __daddr, __ports, __dif)\
           (((__sk)->sk_hash == (__hash))                 &&  \
           (inet_sk(__sk)->daddr          == (__saddr))   &&  \
           (inet_sk(__sk)->rcv_saddr      == (__daddr))   &&  \
           (!((__sk)->sk_bound_dev_if) || ((__sk)->sk_bound_dev_if == (__dif))))
      
      
      - Adds a prefetch(head->chain.first) in 
      __inet_lookup_established()/__tcp_v4_check_established() and 
      __inet6_lookup_established()/__tcp_v6_check_established() and 
      __dccp_v4_check_established() to bring into cache the first element of the 
      list, before the {read|write}_lock(&head->lock);
      Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
      Acked-by: NArnaldo Carvalho de Melo <acme@ghostprotocols.net>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      81c3d547
  17. 29 9月, 2005 1 次提交
  18. 01 5月, 2005 1 次提交
    • J
      [PATCH] misc verify_area cleanups · e49332bd
      Jesper Juhl 提交于
      There were still a few comments left refering to verify_area, and two
      functions, verify_area_skas & verify_area_tt that just wrap corresponding
      access_ok_skas & access_ok_tt functions, just like verify_area does for
      access_ok - deprecate those.
      
      There was also a few places that still used verify_area in commented-out
      code, fix those up to use access_ok.
      
      After applying this one there should not be anything left but finally
      removing verify_area completely, which will happen after a kernel release
      or two.
      Signed-off-by: NJesper Juhl <juhl-lkml@dif.dk>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      e49332bd
  19. 17 4月, 2005 1 次提交
    • L
      Linux-2.6.12-rc2 · 1da177e4
      Linus Torvalds 提交于
      Initial git repository build. I'm not bothering with the full history,
      even though we have it. We can create a separate "historical" git
      archive of that later if we want to, and in the meantime it's about
      3.2GB when imported into git - space that would just make the early
      git days unnecessarily complicated, when we don't have a lot of good
      infrastructure for it.
      
      Let it rip!
      1da177e4