Skip to content

cloud-kernel
cloud-kernel

openanolis / cloud-kernel
12 个月 前同步成功

通知 152
Star 36
Fork 7
cloud-kernel
cloud-kernel

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 17 3月, 2009 1 次提交
  3. 16 3月, 2009 9 次提交
    • I
      tcp: make sure xmit goal size never becomes zero · afece1c6
      由 Ilpo Järvinen 提交于 
      It's not too likely to happen, would basically require crafted
packets (must hit the max guard in tcp_bound_to_half_wnd()).
It seems that nothing that bad would happen as there's tcp_mems
and congestion window that prevent runaway at some point from
hurting all too much (I'm not that sure what all those zero
sized segments we would generate do though in write queue).
Preventing it regardless is certainly the best way to go.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      afece1c6
    • I
      tcp: cache result of earlier divides when mss-aligning things · 2a3a041c
      由 Ilpo Järvinen 提交于 
      The results is very unlikely change every so often so we
hardly need to divide again after doing that once for a
connection. Yet, if divide still becomes necessary we
detect that and do the right thing and again settle for
non-divide state. Takes the u16 space which was previously
taken by the plain xmit_size_goal.

This should take care part of the tso vs non-tso difference
we found earlier.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2a3a041c
    • I
      tcp: simplify tcp_current_mss · 0c54b85f
      由 Ilpo Järvinen 提交于 
      There's very little need for most of the callsites to get
tp->xmit_goal_size updated. That will cost us divide as is,
so slice the function in two. Also, the only users of the
tp->xmit_goal_size are directly behind tcp_current_mss(),
so there's no need to store that variable into tcp_sock
at all! The drop of xmit_goal_size currently leaves 16-bit
hole and some reorganization would again be necessary to
change that (but I'm aiming to fill that hole with u16
xmit_goal_size_segs to cache the results of the remaining
divide to get that tso on regression).

Bring xmit_goal_size parts into tcp.c
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0c54b85f
    • I
      tcp: don't check mtu probe completion in the loop · 72211e90
      由 Ilpo Järvinen 提交于 
      It seems that no variables clash such that we couldn't do
the check just once later on. Therefore move it.

Also kill dead obvious comment, dead argument and add
unlikely since this mtu probe does not happen too often.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      72211e90
    • I
      tcp: consolidate paws check · c887e6d2
      由 Ilpo Järvinen 提交于 
      Wow, it was quite tricky to merge that stream of negations
but I think I finally got it right:

check & replace_ts_recent:
(s32)(rcv_tsval - ts_recent) >= 0                  => 0
(s32)(ts_recent - rcv_tsval) <= 0                  => 0

discard:
(s32)(ts_recent - rcv_tsval)  > TCP_PAWS_WINDOW    => 1
(s32)(ts_recent - rcv_tsval) <= TCP_PAWS_WINDOW    => 0

I toggled the return values of tcp_paws_check around since
the old encoding added yet-another negation making tracking
of truth-values really complicated.
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c887e6d2
    • I
      tcp: kill dead end_seq variable in clean_rtx_queue · c43d558a
      由 Ilpo Järvinen 提交于 
      I've already forgotten what for this was necessary, anyway
it's no longer used (if it ever was).
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c43d558a
    • I
      tcp: remove pointless .dsack/.num_sacks code · 5861f8e5
      由 Ilpo Järvinen 提交于 
      In the pure assignment case, the earlier zeroing is
still in effect.

David S. Miller raised concerns if the ifs are there to avoid
dirtying cachelines. I came to these conclusions:

> We'll be dirty it anyway (now that I check), the first "real" statement
> in tcp_rcv_established is:
>
>       tp->rx_opt.saw_tstamp = 0;
>
> ...that'll land on the same dword. :-/
>
> I suppose the blocks are there just because they had more complexity
> inside when they had to calculate the eff_sacks too (maybe it would
> have been better to just remove them in that drop-patch so you would
> have had less head-ache :-)).
Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5861f8e5
    • J
      pkt_sched: Change misleading code in class delete. · 7cd0a638
      由 Jarek Poplawski 提交于 
      While looking for a possible reason of bugzilla report on HTB oops:
http://bugzilla.kernel.org/show_bug.cgi?id=12858
I found the code in htb_delete calling htb_destroy_class on zero
refcount is very misleading: it can suggest this is a common path, and
destroy is called under sch_tree_lock. Actually, this can never happen
like this because before deletion cops->get() is done, and after
delete a class is still used by tclass_notify. The class destroy is
always called from cops->put(), so without sch_tree_lock.

This doesn't mean much now (since 2.6.27) because all vulnerable calls
were moved from htb_destroy_class to htb_delete, but there was a bug
in older kernels. The same change is done for other classful scheds,
which, it seems, didn't have similar locking problems here.
Reported-by: Nm0sia <m0sia@m0sia.ru>
Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      7cd0a638
    • E
      net: reorder fields of struct socket · 8bdd663a
      由 Eric Dumazet 提交于 
      On x86_64, its rather unfortunate that "wait_queue_head_t wait"
field of "struct socket" spans two cache lines (assuming a 64
bytes cache line in current cpus)

offsetof(struct socket, wait)=0x30
sizeof(wait_queue_head_t)=0x18

This might explain why Kenny Chang noticed that his multicast workload
was performing bad with 64 bit kernels, since more cache lines ping pongs
were involved.

This litle patch moves "wait" field next "fasync_list" so that both
fields share a single cache line, to speedup sock_def_readable()
Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8bdd663a
  5. 15 3月, 2009 25 次提交
  7. 14 3月, 2009 5 次提交
    • G
      ppp: ppp_mp_explode() redesign · 9c705260
      由 Gabriele Paoloni 提交于 
      I found the PPP subsystem to not work properly when connecting channels
with different speeds to the same bundle.

Problem Description:

As the "ppp_mp_explode" function fragments the sk_buff buffer evenly
among the PPP channels that are connected to a certain PPP unit to
make up a bundle, if we are transmitting using an upper layer protocol
that requires an Ack before sending the next packet (like TCP/IP for
example), we will have a bandwidth bottleneck on the slowest channel
of the bundle.

Let's clarify by an example. Let's consider a scenario where we have
two PPP links making up a bundle: a slow link (10KB/sec) and a fast
link (1000KB/sec) working at the best (full bandwidth). On the top we
have a TCP/IP stack sending a 1000 Bytes sk_buff buffer down to the
PPP subsystem. The "ppp_mp_explode" function will divide the buffer in
two fragments of 500B each (we are neglecting all the headers, crc,
flags etc?.). Before the TCP/IP stack sends out the next buffer, it
will have to wait for the ACK response from the remote peer, so it
will have to wait for both fragments to have been sent over the two
PPP links, received by the remote peer and reconstructed. The
resulting behaviour is that, rather than having a bundle working
@1010KB/sec (the sum of the channels bandwidths), we'll have a bundle
working @20KB/sec (the double of the slowest channels bandwidth).


Problem Solution:

The problem has been solved by redesigning the "ppp_mp_explode"
function in such a way to make it split the sk_buff buffer according
to the speeds of the underlying PPP channels (the speeds of the serial
interfaces respectively attached to the PPP channels). Referring to
the above example, the redesigned "ppp_mp_explode" function will now
divide the 1000 Bytes buffer into two fragments whose sizes are set
according to the speeds of the channels where they are going to be
sent on (e.g .  10 Byets on 10KB/sec channel and 990 Bytes on
1000KB/sec channel).  The reworked function grants the same
performances of the original one in optimal working conditions (i.e. a
bundle made up of PPP links all working at the same speed), while
greatly improving performances on the bundles made up of channels
working at different speeds.
Signed-off-by: NGabriele Paoloni <gabriele.paoloni@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      9c705260
    • R
      tcp: '< 0' test on unsigned · a2025b8b
      由 Roel Kluin 提交于 
      promote 'cnt' to size_t, to match 'len'.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a2025b8b
    • R
      x25: '< 0' and '>= 0' test on unsigned · 8db09f26
      由 Roel Kluin 提交于 
      skb->len is an unsigned int, so the test in x25_rx_call_request() always
evaluates to true.

len in x25_sendmsg() is unsigned as well. so -ERRORS returned by x25_output()
are not noticed.
Signed-off-by: NRoel Kluin <roel.kluin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8db09f26
    • D
      ipv4: arp announce, arp_proxy and windows ip conflict verification · 73ce7b01
      由 Denys Fedoryshchenko 提交于 
      Windows (XP at least) hosts on boot, with configured static ip, performing 
address conflict detection, which is defined in RFC3927.
Here is quote of important information:

"
An ARP announcement is identical to the ARP Probe described above, 
except    that now the sender and target IP addresses are both set 
to the host's newly selected IPv4 address. 
"

But it same time this goes wrong with RFC5227.
"
The 'sender IP address' field MUST be set to all zeroes; this is to avoid
polluting ARP caches in other hosts on the same link in the case
where the address turns out to be already in use by another host.
"

When ARP proxy configured, it must not answer to both cases, because 
it is address conflict verification in any case. For Windows it is just 
causing to detect false "ip conflict". Already there is code for RFC5227, so 
just trivially we just check also if source ip == target ip.
Signed-off-by: NDenys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      73ce7b01
    • T
      tulip: Fix for MTU problems with 802.1q tagged frames · 1f8ae0a2
      由 Tomasz Lemiech 提交于 
      The original patch was submitted last year but wasn't discussed or applied
because of missing maintainer's CCs. I only fixed some formatting errors,
but as I saw tulip is very badly formatted and needs further work.

Original description:
This patch fixes MTU problem, which occurs when using 802.1q VLANs. We
should allow receiving frames of up to 1518 bytes in length, instead of
1514.

Based on patch written by Ben McKeegan for 2.4.x kernels. It is archived
at http://www.candelatech.com/~greear/vlan/howto.html#tulip
I've adjusted a few things to make it apply on 2.6.x kernels.

Tested on D-Link DFE-570TX quad-fastethernet card.
Signed-off-by: NTomasz Lemiech <szpajder@staszic.waw.pl>
Signed-off-by: NIvan Vecera <ivecera@redhat.com>
Signed-off-by: NBen McKeegan <ben@netservers.co.uk>
Acked-by: NGrant Grundler <grundler@parisc-linux.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1f8ae0a2