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  1. 26 Mar, 2008 17 commits
  3. 24 Mar, 2008 5 commits
  5. 23 Mar, 2008 5 commits
  7. 22 Mar, 2008 1 commit
    • Herbert Xu's avatar
      [TCP]: Let skbs grow over a page on fast peers · 69d15067
      Herbert Xu authored 
      While testing the virtio-net driver on KVM with TSO I noticed
that TSO performance with a 1500 MTU is significantly worse
compared to the performance of non-TSO with a 16436 MTU.  The
packet dump shows that most of the packets sent are smaller
than a page.

Looking at the code this actually is quite obvious as it always
stop extending the packet if it's the first packet yet to be
sent and if it's larger than the MSS.  Since each extension is
bound by the page size, this means that (given a 1500 MTU) we're
very unlikely to construct packets greater than a page, provided
that the receiver and the path is fast enough so that packets can
always be sent immediately.

The fix is also quite obvious.  The push calls inside the loop
is just an optimisation so that we don't end up doing all the
sending at the end of the loop.  Therefore there is no specific
reason why it has to do so at MSS boundaries.  For TSO, the
most natural extension of this optimisation is to do the pushing
once the skb exceeds the TSO size goal.

This is what the patch does and testing with KVM shows that the
TSO performance with a 1500 MTU easily surpasses that of a 16436
MTU and indeed the packet sizes sent are generally larger than
16436.

I don't see any obvious downsides for slower peers or connections,
but it would be prudent to test this extensively to ensure that
those cases don't regress.
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      69d15067
  9. 21 Mar, 2008 4 commits
  11. 20 Mar, 2008 8 commits
    • YOSHIFUJI Hideaki's avatar
      [IPV6] KCONFIG: Fix description about IPV6_TUNNEL. · 38fe999e
      YOSHIFUJI Hideaki authored 
      Based on notice from "Colin" <colins@sjtu.edu.cn>.
Signed-off-by: default avatarYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      38fe999e
    • Patrick McHardy's avatar
      [TCP]: Fix shrinking windows with window scaling · 607bfbf2
      Patrick McHardy authored 
      When selecting a new window, tcp_select_window() tries not to shrink
the offered window by using the maximum of the remaining offered window
size and the newly calculated window size. The newly calculated window
size is always a multiple of the window scaling factor, the remaining
window size however might not be since it depends on rcv_wup/rcv_nxt.
This means we're effectively shrinking the window when scaling it down.


The dump below shows the problem (scaling factor 2^7):

- Window size of 557 (71296) is advertised, up to 3111907257:

IP 172.2.2.3.33000 > 172.2.2.2.33000: . ack 3111835961 win 557 <...>

- New window size of 514 (65792) is advertised, up to 3111907217, 40 bytes
  below the last end:

IP 172.2.2.3.33000 > 172.2.2.2.33000: . 3113575668:3113577116(1448) ack 3111841425 win 514 <...>

The number 40 results from downscaling the remaining window:

3111907257 - 3111841425 = 65832
65832 / 2^7 = 514
65832 % 2^7 = 40

If the sender uses up the entire window before it is shrunk, this can have
chaotic effects on the connection. When sending ACKs, tcp_acceptable_seq()
will notice that the window has been shrunk since tcp_wnd_end() is before
tp->snd_nxt, which makes it choose tcp_wnd_end() as sequence number.
This will fail the receivers checks in tcp_sequence() however since it
is before it's tp->rcv_wup, making it respond with a dupack.

If both sides are in this condition, this leads to a constant flood of
ACKs until the connection times out.

Make sure the window is never shrunk by aligning the remaining window to
the window scaling factor.
Signed-off-by: default avatarPatrick McHardy <kaber@trash.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      607bfbf2
    • Jarek Poplawski's avatar
      netpoll: zap_completion_queue: adjust skb->users counter · 8a455b08
      Jarek Poplawski authored 
      zap_completion_queue() retrieves skbs from completion_queue where they have
zero skb->users counter.  Before dev_kfree_skb_any() it should be non-zero
yet, so it's increased now.
Reported-and-tested-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      8a455b08
    • Fabio Checconi's avatar
      bridge: use time_before() in br_fdb_cleanup() · 2bec008c
      Fabio Checconi authored 
      In br_fdb_cleanup() next_timer and this_timer are in jiffies, so they
should be compared using the time_after() macro.
Signed-off-by: default avatarFabio Checconi <fabio@gandalf.sssup.it>
Signed-off-by: default avatarStephen Hemminger <stephen.hemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      2bec008c
    • David S. Miller's avatar
      [TG3]: Fix build warning on sparc32. · 7582a335
      David S. Miller authored 
      Sparc MAC address support should be protected consistently
with CONFIG_SPARC, but there was a stray CONFIG_SPARC64
case.

Bump driver version and release date.

Reported by Andrew Morton.
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7582a335
    • Pavel Machek's avatar
      MAINTAINERS: bluez-devel is subscribers-only · 781c2844
      Pavel Machek authored 
      Signed-off-by: default avatarPavel Machek <pavel@suse.cz>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      781c2844
    • Pavel Emelyanov's avatar
      audit: netlink socket can be auto-bound to pid other than current->pid (v2) · 75c0371a
      Pavel Emelyanov authored 
      From:	Pavel Emelyanov <xemul@openvz.org>

This patch is based on the one from Thomas.

The kauditd_thread() calls the netlink_unicast() and passes 
the audit_pid to it. The audit_pid, in turn, is received from 
the user space and the tool (I've checked the audit v1.6.9) 
uses getpid() to pass one in the kernel. Besides, this tool 
doesn't bind the netlink socket to this id, but simply creates 
it allowing the kernel to auto-bind one.

That's the preamble.

The problem is that netlink_autobind() _does_not_ guarantees
that the socket will be auto-bound to the current pid. Instead
it uses the current pid as a hint to start looking for a free
id. So, in case of conflict, the audit messages can be sent
to a wrong socket. This can happen (it's unlikely, but can be)
in case some task opens more than one netlink sockets and then
the audit one starts - in this case the audit's pid can be busy
and its socket will be bound to another id.

The proposal is to introduce an audit_nlk_pid in audit subsys,
that will point to the netlink socket to send packets to. It
will most often be equal to audit_pid. The socket id can be 
got from the skb's netlink CB right in the audit_receive_msg.
The audit_nlk_pid reset to 0 is not required, since all the
decisions are taken based on audit_pid value only.

Later, if the audit tools will bind the socket themselves, the
kernel will have to provide a way to setup the audit_nlk_pid
as well.

A good side effect of this patch is that audit_pid can later 
be converted to struct pid, as it is not longer safe to use 
pid_t-s in the presence of pid namespaces. But audit code still 
uses the tgid from task_struct in the audit_signal_info and in
the audit_filter_syscall.
Signed-off-by: default avatarThomas Graf <tgraf@suug.ch>
Signed-off-by: default avatarPavel Emelyanov <xemul@openvz.org>
Acked-by: default avatarEric Paris <eparis@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      75c0371a
    • Andre Noll's avatar
      [NET]: Fix permissions of /proc/net · 4f42c288
      Andre Noll authored 
      commit e9720acd ([NET]: Make /proc/net a symlink on /proc/self/net (v3))
broke ganglia and probably other applications that read /proc/net/dev.

This is due to the change of permissions of /proc/net that was
introduced in that commit.

Before: dr-xr-xr-x 5 root root 0 Mar 19 11:30 /proc/net
After: dr-xr--r-- 5 root root 0 Mar 19 11:29 /proc/self/net

This patch restores the permissions to the old value which makes
ganglia happy again.

Pavel Emelyanov says:

	This also broke the postfix, as it was reported in bug #10286
	and described in detail by Benjamin.
Signed-off-by: default avatarAndre Noll <maan@systemlinux.org>
Acked-by: default avatarPavel Emelyanov <xemul@openvz.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      4f42c288
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