Complete the work started with commit
6602a4baf4 ('net: Make userland include
of netlink.h more sane').
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
<linux/types.h> defines __kernel_pid_t for userland; pid_t is
defined elsewhere (and potentially differently).
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
<linux/if_ppox.h> uses ETH_ALEN, defined in <linux/if_ether.h>.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch series 109f6e39..7361c36c back in 2.6.36 added functionality to
allow credentials to work across pid namespaces for packets sent via
UNIX sockets. However, the atomic reference counts on pid and
credentials caused plenty of cache bouncing when there are numerous
threads of the same pid sharing a UNIX socket. This patch mitigates the
problem by eliminating extraneous reference counts on pid and
credentials on both send and receive path of UNIX sockets. I found a 2x
improvement in hackbench's threaded case.
On the receive path in unix_dgram_recvmsg, currently there is an
increment of reference count on pid and credentials in scm_set_cred.
Then there are two decrement of the reference counts. Once in scm_recv
and once when skb_free_datagram call skb->destructor function
unix_destruct_scm. One pair of increment and decrement of ref count on
pid and credentials can be eliminated from the receive path. Until we
destroy the skb, we already set a reference when we created the skb on
the send side.
On the send path, there are two increments of ref count on pid and
credentials, once in scm_send and once in unix_scm_to_skb. Then there
is a decrement of the reference counts in scm_destroy's call to
scm_destroy_cred at the end of unix_dgram_sendmsg functions. One pair
of increment and decrement of the reference counts can be removed so we
only need to increment the ref counts once.
By incorporating these changes, for hackbench running on a 4 socket
NHM-EX machine with 40 cores, the execution of hackbench on
50 groups of 20 threads sped up by factor of 2.
Hackbench command used for testing:
./hackbench 50 thread 2000
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With this patch a HEARTBEAT chunk is bundled into the ASCONF-ACK
for ADD IP ADDRESS, confirming the new destination as quickly as
possible.
Signed-off-by: Michio Honda <micchie@sfc.wide.ad.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements Proportional Rate Reduction (PRR) for TCP.
PRR is an algorithm that determines TCP's sending rate in fast
recovery. PRR avoids excessive window reductions and aims for
the actual congestion window size at the end of recovery to be as
close as possible to the window determined by the congestion control
algorithm. PRR also improves accuracy of the amount of data sent
during loss recovery.
The patch implements the recommended flavor of PRR called PRR-SSRB
(Proportional rate reduction with slow start reduction bound) and
replaces the existing rate halving algorithm. PRR improves upon the
existing Linux fast recovery under a number of conditions including:
1) burst losses where the losses implicitly reduce the amount of
outstanding data (pipe) below the ssthresh value selected by the
congestion control algorithm and,
2) losses near the end of short flows where application runs out of
data to send.
As an example, with the existing rate halving implementation a single
loss event can cause a connection carrying short Web transactions to
go into the slow start mode after the recovery. This is because during
recovery Linux pulls the congestion window down to packets_in_flight+1
on every ACK. A short Web response often runs out of new data to send
and its pipe reduces to zero by the end of recovery when all its packets
are drained from the network. Subsequent HTTP responses using the same
connection will have to slow start to raise cwnd to ssthresh. PRR on
the other hand aims for the cwnd to be as close as possible to ssthresh
by the end of recovery.
A description of PRR and a discussion of its performance can be found at
the following links:
- IETF Draft:
http://tools.ietf.org/html/draft-mathis-tcpm-proportional-rate-reduction-01
- IETF Slides:
http://www.ietf.org/proceedings/80/slides/tcpm-6.pdfhttp://tools.ietf.org/agenda/81/slides/tcpm-2.pdf
- Paper to appear in Internet Measurements Conference (IMC) 2011:
Improving TCP Loss Recovery
Nandita Dukkipati, Matt Mathis, Yuchung Cheng
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use IFF_UNICAST_FTL to find out if driver handles unicast address
filtering. In case it does not, promisc mode is entered.
Patch also fixes following drivers:
stmmac, niu: support uc filtering and yet it propagated
ndo_set_multicast_list
bna, benet, pxa168_eth, ks8851, ks8851_mll, ksz884x : has set
ndo_set_rx_mode but do not support uc filtering
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The l4_rxhash flag was added to the skb structure to indicate
that the rxhash value was computed over the 4 tuple for the
packet which includes the port information in the encapsulated
transport packet. This is used by the stack to preserve the
rxhash value in __skb_rx_tunnel.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many implementations ignore the value of max_frames and do not
treat usecs == 0 as special. Document this as deprecated.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also explicitly state how to disable interrupt coalescing.
Remove the now-redundant text from field descriptions.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current descriptions state that these fields specify 'How many
packets to delay ... after a packet ...' which implies that the
hardware should wait for (max_coalesced_frames + 1) completions before
generating an interrupt. It is also stated that setting both this
field and the corresponding 'coalesce_usecs' field to 0 is invalid.
Together, this implies that the hardware must always be configured
to delay a completion IRQ for at least 1 usec or 1 more completion.
I believe that the addition of 1 is not intended, and David Miller
confirms that the original implementation (in tg3) does not do this.
Clarify the descriptions of these fields to avoid this interpretation.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reorders and duplicates some wording, but should make no
substantive changes.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since sungem_phy is used by multiple, unrelated, drivers make it
build as a real module under drivers/net.
depmod will pick up the symbol dependency and make sure sungem_phy.ko
gets loaded any time sungem.ko or spider_net.ko is loaded.
Tested-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes build failures of the spider_net driver because it tries
to use a convoluted path to include this header.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current transport mechanism for af_iucv is the z/VM offered
communications facility IUCV. To provide equivalent support when
running Linux in an LPAR, HiperSockets transport is added to the
AF_IUCV address family. It requires explicit binding of an AF_IUCV
socket to a HiperSockets device. A new packet_type ETH_P_AF_IUCV
is announced. An af_iucv specific transport header is defined
preceding the skb data. A small protocol is implemented for
connecting and for flow control/congestion management.
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Reviewed-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new ethertype for af_iucv over s/390 HiperSockets transport. Since
HiperSockets is not a real ethernet hw this is not an officially registered ID.
Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
