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  1. Aug 10, 2013
  3. Aug 09, 2013
  5. Aug 07, 2013
  7. Aug 05, 2013
    • fan.du's avatar
      sctp: Pack dst_cookie into 1st cacheline hole for 64bit host · 5a139296
      fan.du authored 
      

As dst_cookie is used in fast path sctp_transport_dst_check.

Before:
struct sctp_transport {
	struct list_head           transports;           /*     0    16 */
	atomic_t                   refcnt;               /*    16     4 */
	__u32                      dead:1;               /*    20:31  4 */
	__u32                      rto_pending:1;        /*    20:30  4 */
	__u32                      hb_sent:1;            /*    20:29  4 */
	__u32                      pmtu_pending:1;       /*    20:28  4 */

	/* XXX 28 bits hole, try to pack */

	__u32                      sack_generation;      /*    24     4 */

	/* XXX 4 bytes hole, try to pack */

	struct flowi               fl;                   /*    32    64 */
	/* --- cacheline 1 boundary (64 bytes) was 32 bytes ago --- */
	union sctp_addr            ipaddr;               /*    96    28 */

After:
struct sctp_transport {
	struct list_head           transports;           /*     0    16 */
	atomic_t                   refcnt;               /*    16     4 */
	__u32                      dead:1;               /*    20:31  4 */
	__u32                      rto_pending:1;        /*    20:30  4 */
	__u32                      hb_sent:1;            /*    20:29  4 */
	__u32                      pmtu_pending:1;       /*    20:28  4 */

	/* XXX 28 bits hole, try to pack */

	__u32                      sack_generation;      /*    24     4 */
	u32                        dst_cookie;           /*    28     4 */
	struct flowi               fl;                   /*    32    64 */
	/* --- cacheline 1 boundary (64 bytes) was 32 bytes ago --- */
	union sctp_addr            ipaddr;               /*    96    28 */

Signed-off-by: default avatarFan Du <fan.du@windriver.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      5a139296
  9. Aug 03, 2013
  11. Aug 02, 2013
  13. Aug 01, 2013
    • Cong Wang's avatar
      net: rename CONFIG_NET_LL_RX_POLL to CONFIG_NET_RX_BUSY_POLL · e0d1095a
      Cong Wang authored 
      

Eliezer renames several *ll_poll to *busy_poll, but forgets
CONFIG_NET_LL_RX_POLL, so in case of confusion, rename it too.

Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: default avatarCong Wang <amwang@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e0d1095a
    • Cong Wang's avatar
      net: fix a compile error when CONFIG_NET_LL_RX_POLL is not set · dfcefb0b
      Cong Wang authored 
      

When CONFIG_NET_LL_RX_POLL is not set, I got:

net/socket.c: In function ‘sock_poll’:
net/socket.c:1165:4: error: implicit declaration of function ‘sk_busy_loop’ [-Werror=implicit-function-declaration]

Fix this by adding a nop when !CONFIG_NET_LL_RX_POLL.

Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: default avatarCong Wang <amwang@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      dfcefb0b
    • Michal Kubeček's avatar
      ipv6: prevent fib6_run_gc() contention · 2ac3ac8f
      Michal Kubeček authored 
      

On a high-traffic router with many processors and many IPv6 dst
entries, soft lockup in fib6_run_gc() can occur when number of
entries reaches gc_thresh.

This happens because fib6_run_gc() uses fib6_gc_lock to allow
only one thread to run the garbage collector but ip6_dst_gc()
doesn't update net->ipv6.ip6_rt_last_gc until fib6_run_gc()
returns. On a system with many entries, this can take some time
so that in the meantime, other threads pass the tests in
ip6_dst_gc() (ip6_rt_last_gc is still not updated) and wait for
the lock. They then have to run the garbage collector one after
another which blocks them for quite long.

Resolve this by replacing special value ~0UL of expire parameter
to fib6_run_gc() by explicit "force" parameter to choose between
spin_lock_bh() and spin_trylock_bh() and call fib6_run_gc() with
force=false if gc_thresh is reached but not max_size.

Signed-off-by: default avatarMichal Kubecek <mkubecek@suse.cz>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2ac3ac8f
    • Joe Perches's avatar
      cls_cgroup.h netprio_cgroup.h: Remove extern from function prototypes · 37830721
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      37830721
    • Joe Perches's avatar
      checksum: Remove extern from function prototypes · 4fc70747
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4fc70747
    • Joe Perches's avatar
      cfg80211.h/mac80211.h: Remove extern from function prototypes · 10dd9b7c
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      10dd9b7c
    • Joe Perches's avatar
      ax25.h: Remove extern from function prototypes · c1d8f804
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c1d8f804
    • Joe Perches's avatar
      arp/neighbour.h: Remove extern from function prototypes · 90972b22
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      90972b22
    • Joe Perches's avatar
      af_rxrpc.h: Remove extern from function prototypes · cd2cf63a
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      cd2cf63a
    • Joe Perches's avatar
      af_unix.h: Remove extern from function prototypes · b60a8280
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b60a8280
    • Joe Perches's avatar
      addrconf.h: Remove extern function prototypes · e8e54d3c
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      e8e54d3c
    • Stefan Tomanek's avatar
      fib_rules: add .suppress operation · 7764a45a
      Stefan Tomanek authored 
      

This change adds a new operation to the fib_rules_ops struct; it allows the
suppression of routing decisions if certain criteria are not met by its
results.

The first implemented constraint is a minimum prefix length added to the
structures of routing rules. If a rule is added with a minimum prefix length
>0, only routes meeting this threshold will be considered. Any other (more
general) routing table entries will be ignored.

When configuring a system with multiple network uplinks and default routes, it
is often convinient to reference the main routing table multiple times - but
omitting the default route. Using this patch and a modified "ip" utility, this
can be achieved by using the following command sequence:

  $ ip route add table secuplink default via 10.42.23.1

  $ ip rule add pref 100            table main prefixlength 1
  $ ip rule add pref 150 fwmark 0xA table secuplink

With this setup, packets marked 0xA will be processed by the additional routing
table "secuplink", but only if no suitable route in the main routing table can
be found. By using a minimal prefixlength of 1, the default route (/0) of the
table "main" is hidden to packets processed by rule 100; packets traveling to
destinations with more specific routing entries are processed as usual.

Signed-off-by: default avatarStefan Tomanek <stefan.tomanek@wertarbyte.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7764a45a
    • Joe Perches's avatar
      net: Remove extern from include/net/ scheduling prototypes · 5c15257f
      Joe Perches authored 
      

There are a mix of function prototypes with and without extern
in the kernel sources.  Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler.  Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Reflow modified prototypes to 80 columns.

Signed-off-by: default avatarJoe Perches <joe@perches.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      5c15257f
  15. Jul 31, 2013
  17. Jul 30, 2013
  19. Jul 28, 2013
  21. Jul 25, 2013
    • Eric Dumazet's avatar
      tcp: TCP_NOTSENT_LOWAT socket option · c9bee3b7
      Eric Dumazet authored 
      

Idea of this patch is to add optional limitation of number of
unsent bytes in TCP sockets, to reduce usage of kernel memory.

TCP receiver might announce a big window, and TCP sender autotuning
might allow a large amount of bytes in write queue, but this has little
performance impact if a large part of this buffering is wasted :

Write queue needs to be large only to deal with large BDP, not
necessarily to cope with scheduling delays (incoming ACKS make room
for the application to queue more bytes)

For most workloads, using a value of 128 KB or less is OK to give
applications enough time to react to POLLOUT events in time
(or being awaken in a blocking sendmsg())

This patch adds two ways to set the limit :

1) Per socket option TCP_NOTSENT_LOWAT

2) A sysctl (/proc/sys/net/ipv4/tcp_notsent_lowat) for sockets
not using TCP_NOTSENT_LOWAT socket option (or setting a zero value)
Default value being UINT_MAX (0xFFFFFFFF), meaning this has no effect.

This changes poll()/select()/epoll() to report POLLOUT
only if number of unsent bytes is below tp->nosent_lowat

Note this might increase number of sendmsg()/sendfile() calls
when using non blocking sockets,
and increase number of context switches for blocking sockets.

Note this is not related to SO_SNDLOWAT (as SO_SNDLOWAT is
defined as :
 Specify the minimum number of bytes in the buffer until
 the socket layer will pass the data to the protocol)

Tested:

netperf sessions, and watching /proc/net/protocols "memory" column for TCP

With 200 concurrent netperf -t TCP_STREAM sessions, amount of kernel memory
used by TCP buffers shrinks by ~55 % (20567 pages instead of 45458)

lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat
lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols
TCPv6     1880      2   45458   no     208   yes  ipv6        y  y  y  y  y  y  y  y  y  y  y  y  y  n  y  y  y  y  y
TCP       1696    508   45458   no     208   yes  kernel      y  y  y  y  y  y  y  y  y  y  y  y  y  n  y  y  y  y  y

lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat
lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols
TCPv6     1880      2   20567   no     208   yes  ipv6        y  y  y  y  y  y  y  y  y  y  y  y  y  n  y  y  y  y  y
TCP       1696    508   20567   no     208   yes  kernel      y  y  y  y  y  y  y  y  y  y  y  y  y  n  y  y  y  y  y

Using 128KB has no bad effect on the throughput or cpu usage
of a single flow, although there is an increase of context switches.

A bonus is that we hold socket lock for a shorter amount
of time and should improve latencies of ACK processing.

lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat
lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3
OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf.
Local       Remote      Local  Elapsed Throughput Throughput  Local Local  Remote Remote Local   Remote  Service
Send Socket Recv Socket Send   Time               Units       CPU   CPU    CPU    CPU    Service Service Demand
Size        Size        Size   (sec)                          Util  Util   Util   Util   Demand  Demand  Units
Final       Final                                             %     Method %      Method
1651584     6291456     16384  20.00   17447.90   10^6bits/s  3.13  S      -1.00  U      0.353   -1.000  usec/KB

 Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3':

           412,514 context-switches

     200.034645535 seconds time elapsed

lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat
lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3
OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf.
Local       Remote      Local  Elapsed Throughput Throughput  Local Local  Remote Remote Local   Remote  Service
Send Socket Recv Socket Send   Time               Units       CPU   CPU    CPU    CPU    Service Service Demand
Size        Size        Size   (sec)                          Util  Util   Util   Util   Demand  Demand  Units
Final       Final                                             %     Method %      Method
1593240     6291456     16384  20.00   17321.16   10^6bits/s  3.35  S      -1.00  U      0.381   -1.000  usec/KB

 Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3':

         2,675,818 context-switches

     200.029651391 seconds time elapsed

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-By: default avatarYuchung Cheng <ycheng@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c9bee3b7
    • Eric Dumazet's avatar
      net: add sk_stream_is_writeable() helper · 64dc6130
      Eric Dumazet authored 
      

Several call sites use the hardcoded following condition :

sk_stream_wspace(sk) >= sk_stream_min_wspace(sk)

Lets use a helper because TCP_NOTSENT_LOWAT support will change this
condition for TCP sockets.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Acked-by: default avatarNeal Cardwell <ncardwell@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      64dc6130
    • Daniel Borkmann's avatar
      net: sctp: trivial: update mailing list address · 91705c61
      Daniel Borkmann authored 
      

The SCTP mailing list address to send patches or questions
to is linux-sctp@vger.kernel.org and not
lksctp-developers@lists.sourceforge.net anymore. Therefore,
update all occurences.

Signed-off-by: default avatarDaniel Borkmann <dborkman@redhat.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Acked-by: default avatarVlad Yasevich <vyasevich@gmail.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      91705c61
  23. Jul 23, 2013
  25. Jul 22, 2013