Looks like everything is already ready.
Required for ebtables(8) for one thing.
Also, required for ipmr per-netns (coming soon). (Benjamin)
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Acked-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The original message was unhelpful and extremely alarming to our poor
users, despite its charm. Make it less frightening.
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the TCP-specific portion of GRO. The criterion for
merging is extremely strict (the TCP header must match exactly apart
from the checksum) so as to allow refragmentation. Otherwise this
is pretty much identical to LRO, except that we support the merging
of ECN packets.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds GRO support for IPv4.
The criteria for merging is more stringent than LRO, in particular,
we require all fields in the IP header to be identical except for
the length, ID and checksum. In addition, the ID must form an
arithmetic sequence with a difference of one.
The ID requirement might seem overly strict, however, most hardware
TSO solutions already obey this rule. Linux itself also obeys this
whether GSO is in use or not.
In future we could relax this rule by storing the IDs (or rather
making sure that we don't drop them when pulling the aggregate
skb's tail).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit e099a17357
(netfilter: netns nat: per-netns NAT table) renamed the
nat_table from __nat_table to nat_table without updating the
__RW_LOCK_UNLOCKED(__nat_table.lock).
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch addresses a book-keeping issue in tcp_vegas.c. At present
tcp_vegas does separate book-keeping of cwnd based on packet sequence
numbers. A mismatch can develop between this book-keeping and
tp->snd_cwnd due, for example, to delayed acks acking multiple
packets. When vegas transitions to reno operation (e.g. following
loss), then this mismatch leads to incorrect behaviour (akin to a cwnd
backoff). This seems mostly to affect operation at low cwnds where
delayed acking can lead to a significant fraction of cwnd being
covered by a single ack, leading to the book-keeping mismatch. This
patch modifies the congestion avoidance update to avoid the need for
separate book-keeping while leaving vegas congestion avoidance
functionally unchanged. A secondary advantage of this modification is
that the use of fixed-point (via V_PARAM_SHIFT) and 64 bit arithmetic
is no longer necessary, simplifying the code.
Some example test measurements with the patched code (confirming no functional
change in the congestion avoidance algorithm) can be seen at:
http://www.hamilton.ie/doug/vegaspatch/
Signed-off-by: Doug Leith <doug.leith@nuim.ie>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since jiffies is unsigned long, the types get expanded into
that and after long enough time the difference will therefore
always be > 1 (and that probably happens near boot as well as
iirc the first jiffies wrap is scheduler close after boot to
find out problems related to that early).
This was originally noted by Bill Fink in Dec'07 but nobody
never ended fixing it.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
tcp_minshall_update is not significant difference since it only
checks for not full-sized skb which is BUG'ed on the push_one
path anyway.
tcp_snd_test is tcp_nagle_test+tcp_cwnd_test+tcp_snd_wnd_test,
just the order changed slightly.
net/ipv4/tcp_output.c:
tcp_snd_test | -89
tcp_mss_split_point | -91
tcp_may_send_now | +53
tcp_cwnd_validate | -98
tso_fragment | -239
__tcp_push_pending_frames | -1340
tcp_push_one | -146
7 functions changed, 53 bytes added, 2003 bytes removed, diff: -1950
net/ipv4/tcp_output.c:
tcp_write_xmit | +1772
1 function changed, 1772 bytes added, diff: +1772
tcp_output.o.new:
8 functions changed, 1825 bytes added, 2003 bytes removed, diff: -178
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
There are just too many args to some sacktag functions. This
idea was first proposed by David S. Miller around a year ago,
and the current situation is much worse that what it was back
then.
tcp_sacktag_one can be made a bit simpler by returning the
new sacked (it can be achieved with a single variable though
the previous code "caching" sacked into a local variable and
therefore it is not exactly equal but the results will be the
same).
codiff on x86_64
tcp_sacktag_one | -15
tcp_shifted_skb | -50
tcp_match_skb_to_sack | -1
tcp_sacktag_walk | -64
tcp_sacktag_write_queue | -59
tcp_urg | +1
tcp_event_data_recv | -1
7 functions changed, 1 bytes added, 190 bytes removed, diff: -189
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
I noticed that since skb->len has nothing to do with actual segment
length with gso, we need to figure it out separately, reuse
a function from the recent shifting stuff (generalize it).
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
S|R won't result in S if just SACK is received. DSACK is
another story (but it is covered correctly already).
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes a bug in tcp_vegas.c. At the moment this code leaves
ssthresh untouched. However, this means that the vegas congestion
control algorithm is effectively unable to reduce cwnd below the
ssthresh value (if the vegas update lowers the cwnd below ssthresh,
then slow start is activated to raise it back up). One example where
this matters is when during slow start cwnd overshoots the link
capacity and a flow then exits slow start with ssthresh set to a value
above where congestion avoidance would like to adjust it.
Signed-off-by: Doug Leith <doug.leith@nuim.ie>
Signed-off-by: David S. Miller <davem@davemloft.net>
Today, iproute2 fails to show multicast forwarding unresolved cache
entries while scanning /proc/net/ip_mr_cache.
Indeed, it expects to see -1 in 'Iif' column to identify unresolved
entries but the kernel outputs 65535. It's a signed/unsigned issue:
'Iif', the source interface, is retrieved from member mfc_parent in
struct mfc_cache. mfc_parent is a vifi_t: unsigned short, but is
displayed in ipmr_mfc_seq_show() as "%-3d", signed integer.
In unresolevd entries, the 65535 value (0xFFFF) comes from this define:
#define ALL_VIFS ((vifi_t)(-1))
That may explains why the guy who added support for this in iproute2
thought a -1 should be expected.
I don't know if this must be fixed in kernel or in iproute2. Who is
right? What is the correct API? How was it designed originally?
I let you decide if it should goes in the kernel or be fixed in iproute2.
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
/proc/net/ip_mr_cache and /proc/net/ip6_mr_cache displays garbage when
showing unresolved mfc_cache entries.
[root@qemu tests]# cat /proc/net/ip_mr_cache
Group Origin Iif Pkts Bytes Wrong Oifs
014C00EF 010014AC 1 10 10050 0 2:1 3:1
024C00EF 010014AC 65535 514 2 -559067475
The first line is correct. It is a resolved cache entry, 10 packets used it...
The second line represents an unresolved entry, and the columns Pkts(4th),
Bytes(5th) and Wrong(6th) just show garbage.
In struct mfc_cache, there's an union to store data for resolved and
unresolved cases. And what ipmr_mfc_seq_show() is printing in these
columns for the unresolved entries is some bytes from mfc_cache.mfc_un.res.
Bad.
(eg. In our case -559067475 is in fact 0xdead4ead which is the spinlock
magic from mfc_cache.mfc_un.unres.unresolved.lock.magic).
This patch replaces the garbage data written in these columns for the
unresolved entries by '0' (zeros) which is more correct.
This change doesn't break the ABI.
Also, mfc->mfc_un.res.pkt, mfc->mfc_un.res.bytes, mfc->mfc_un.res.wrong_if
are unsigned long.
It applies on top of net-next-2.6.
The patch for net-2.6 is slightly different because of the NIP6_FMT to
%pI6 conversion that was made in the seq_printf.
Changelog:
==========
V2:
* Instead of breaking the ABI by suppressing the columns that have no
meaning for unresolved entries, fill them with 0 values.
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
I should have noticed this earlier... :-) The previous solution
to URG+GSO/TSO will cause SACK block tcp_fragment to do zig-zig
patterns, or even worse, a steep downward slope into packet
counting because each skb pcount would be truncated to pcount
of 2 and then the following fragments of the later portion would
restore the window again.
Basically this reverts "tcp: Do not use TSO/GSO when there is
urgent data" (33cf71cee1). It also removes some unnecessary code
from tcp_current_mss that didn't work as intented either (could
be that something was changed down the road, or it might have
been broken since the dawn of time) because it only works once
urg is already written while this bug shows up starting from
~64k before the urg point.
The retransmissions already are split to mss sized chunks, so
only new data sending paths need splitting in case they have
a segment otherwise suitable for gso/tso. The actually check
can be improved to be more narrow but since this is late -rc
already, I'll postpone thinking the more fine-grained things.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexey Dobriyan
Matt Mackall
Ilpo Järvinen
Herbert Xu
David S. Miller
Steven Rostedt
Doug Leith
Benjamin Thery