Alexander Duyck [Thu, 12 Jul 2012 14:23:50 +0000 (14:23 +0000)]
net: Update alloc frag to reduce get/put page usage and recycle pages
This patch is meant to help improve performance by reducing the number of
locked operations required to allocate a frag on x86 and other platforms.
This is accomplished by using atomic_set operations on the page count
instead of calling get_page and put_page. It is based on work originally
provided by Eric Dumazet.
In addition it also helps to reduce memory overhead when using TCP. This
is done by recycling the page if the only holder of the frame is the
netdev_alloc_frag call itself. This can occur when skb heads are stolen by
either GRO or TCP and the driver providing the packets is using paged frags
to store all of the data for the packets.
Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
be2net: Fix error while toggling autoneg of pause parameters
Autonegotiation of pause parameters is possible only on some PHYs.
Ability of autoneg of pause parameters is reported by adapter.
Autoneg of pause parameters cannot be changed from driver.
Fix driver to give error when autoneg mode is toggled by user.
Signed-off-by: Padmanabh Ratnakar <padmanabh.ratnakar@emulex.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Can be used to match packets against netfilter ip sets created via ipset(8).
skb->sk_iif is used as 'incoming interface', skb->dev is 'outgoing interface'.
Since ipset is usually called from netfilter, the ematch
initializes a fake xt_action_param, pulls the ip header into the
linear area and also sets skb->data to the IP header (otherwise
matching Layer 4 set types doesn't work).
Tested-by: Mr Dash Four <mr.dash.four@googlemail.com> Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
First update the adapter variables with the current speed and
mode before fire the notification. Otherwise, the get_settings()
may provide old values.
Signed-off-by: Flavio Leitner <fbl@redhat.com> Acked-by: Rajesh Borundia <rajesh.borundia@qlogic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
6lowpan module starts collecting incomming frames and fragments
right after lowpan_module_init() therefor it will be better to
clean unfinished fragments in lowpan_cleanup_module() function
instead of doing it when link goes down.
Changed spinlocks type to prevent deadlock with expired timer event
and removed unused one.
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Function lowpan_alloc_new_frame() takes u8 tag as an argument. However,
its only caller, lowpan_process_data() passes down a u16. Hence,
the tag value can get corrupted. This prevent 6lowpan fragment reassembly of a
message when the fragment tag value is over 256.
Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com> Cc: Tony Cheneau <tony.cheneau@amnesiak.org> Signed-off-by: David S. Miller <davem@davemloft.net>
net: add support for NS8390 based eth controllers on some ColdFire CPU boards
A number of older ColdFire CPU based boards use NS8390 based network
controllers. Most use the Davicom 9008F or the UMC 9008F. This driver
provides the support code to get these devices working on these platforms.
Generally the NS8390 based eth device is direct connected via the general
purpose bus of the ColdFire CPU. So its addressing and interrupt setup is
fixed on each of the different platforms (classic platform setup).
This driver is based on the other drivers/net/ethernet/8390 drivers, and
includes the lib8390.c code. It uses the existing definitions of the
board NS8390 device addresses, interrupts and access types from the
arch/m68k/include/asm/mcf8390.h, but moves the IO access functions into
the driver code and out of that header.
Signed-off-by: Greg Ungerer <gerg@uclinux.org> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Thu, 12 Jul 2012 10:49:19 +0000 (03:49 -0700)]
Merge branch 'redirect_via_sock'
As described in my patch series from the other day, we need to
rearrange redirect handling so that the local initiators of packets
(sockets, tunnels, xfrms, etc.) that implement the protocols compute
the route and pass this down into the ipv4/ipv6 routing code.
These changes here do so by implementing a new dst_ops->redirect
method.
No more do we have this funny code that tries several different sets
of routing keys to try and figure out which route the redirect should
actually be applied to.
No more do we have the problem wherein TOS rewriting causes problems
for us.
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Wed, 11 Jul 2012 05:50:31 +0000 (05:50 +0000)]
tcp: TCP Small Queues
This introduce TSQ (TCP Small Queues)
TSQ goal is to reduce number of TCP packets in xmit queues (qdisc &
device queues), to reduce RTT and cwnd bias, part of the bufferbloat
problem.
sk->sk_wmem_alloc not allowed to grow above a given limit,
allowing no more than ~128KB [1] per tcp socket in qdisc/dev layers at a
given time.
TSO packets are sized/capped to half the limit, so that we have two
TSO packets in flight, allowing better bandwidth use.
As a side effect, setting the limit to 40000 automatically reduces the
standard gso max limit (65536) to 40000/2 : It can help to reduce
latencies of high prio packets, having smaller TSO packets.
This means we divert sock_wfree() to a tcp_wfree() handler, to
queue/send following frames when skb_orphan() [2] is called for the
already queued skbs.
Results on my dev machines (tg3/ixgbe nics) are really impressive,
using standard pfifo_fast, and with or without TSO/GSO.
Without reduction of nominal bandwidth, we have reduction of buffering
per bulk sender :
< 1ms on Gbit (instead of 50ms with TSO)
< 8ms on 100Mbit (instead of 132 ms)
I no longer have 4 MBytes backlogged in qdisc by a single netperf
session, and both side socket autotuning no longer use 4 Mbytes.
As skb destructor cannot restart xmit itself ( as qdisc lock might be
taken at this point ), we delegate the work to a tasklet. We use one
tasklest per cpu for performance reasons.
If tasklet finds a socket owned by the user, it sets TSQ_OWNED flag.
This flag is tested in a new protocol method called from release_sock(),
to eventually send new segments.
[1] New /proc/sys/net/ipv4/tcp_limit_output_bytes tunable
[2] skb_orphan() is usually called at TX completion time,
but some drivers call it in their start_xmit() handler.
These drivers should at least use BQL, or else a single TCP
session can still fill the whole NIC TX ring, since TSQ will
have no effect.
Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Dave Taht <dave.taht@bufferbloat.net> Cc: Tom Herbert <therbert@google.com> Cc: Matt Mathis <mattmathis@google.com> Cc: Yuchung Cheng <ycheng@google.com> Cc: Nandita Dukkipati <nanditad@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Alexander Duyck [Thu, 12 Jul 2012 00:18:04 +0000 (17:18 -0700)]
tcp: Fix out of bounds access to tcpm_vals
The recent patch "tcp: Maintain dynamic metrics in local cache." introduced
an out of bounds access due to what appears to be a typo. I believe this
change should resolve the issue by replacing the access to RTAX_CWND with
TCP_METRIC_CWND.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Alexander Duyck [Sat, 5 May 2012 05:31:04 +0000 (05:31 +0000)]
ixgbe: Merge RSS and flow director ring register caching and configuration
There are really only 3 modes that can control the number of queues. Those
are RSS, DCB, and VMDq/SR-IOV. Currently we have things much more broken
up than they need to be for how we are configuring the rings. In order to
try and straiten some of this out I am going to start merging similar
functionality into single functions. To start with I am merging the Flow
Director ring configuration into the RSS ring configuration since Flow
Director cannot function with DCB or SR-IOV.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Alexander Duyck [Sat, 5 May 2012 05:30:59 +0000 (05:30 +0000)]
ixgbe: Clean up a useless switch statement and dead code in configure_srrctl
This patch replaces a switch statement for an 82598 workaround with an if
statement that only applies to 82598. In addition I am pulling out several
dead pieces of code and instead of reading the SRRCTL register and then
modifying it we are just writing a value which we generate from scratch.
Finally I am also removing any drop enable related code since that was
moved to a function of its own.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Alexander Duyck [Sat, 5 May 2012 05:30:53 +0000 (05:30 +0000)]
ixgbe: Add feature offset value to ring features
The mask value for ring features was overloaded for FCoE which can lead to
some confusion. In order to avoid any confusion I am splitting the mask
value and adding an offset value. This can be used for the start of the
FCoE rings, and in the future I hope to use it to store the start of the
registers for SR-IOV.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Alexander Duyck [Thu, 10 May 2012 00:01:46 +0000 (00:01 +0000)]
ixgbe: Add upper limit to ring features
We are currently using indices to indicate the upper limit on a ring
feature. However since we can switch back and forth on features such as
DCB and that has effects on other features such as RSS it is preferable to
instead store the upper limit separate from the current value for the
number of rings related to the feature.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Alexander Duyck [Sat, 5 May 2012 05:30:43 +0000 (05:30 +0000)]
ixgbe: count q_vectors instead of MSI-X vectors
It makes much more sense for us to count q_vectors instead of MSI-X
vectors. We were using num_msix_vectors to find the number of q_vectors in
multiple places. This was wasteful since we only had one place that
actually needs the number of MSI-X vectors and that is in slow path.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Li RongQing [Mon, 9 Jul 2012 23:56:12 +0000 (23:56 +0000)]
bridge: fix endian
mld->mld_maxdelay is net endian, so we should use ntohs, not htons
CC: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Li RongQing [Mon, 9 Jul 2012 20:56:06 +0000 (20:56 +0000)]
ksz884x: fix Endian
ETH_P_IP is host Endian, skb->protocol is big Endian, when
compare them, Using htons on skb->protocol is wrong.
And fix two code style issues: indentation and remove
unnecessary parentheses.
CC: Tristram Ha <Tristram.Ha@micrel.com> CC: Ben Hutchings <bhutchings@solarflare.com> CC: Joe Perches <joe@perches.com> Signed-off-by: Li RongQing <roy.qing.li@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Chan [Tue, 10 Jul 2012 10:04:40 +0000 (10:04 +0000)]
bnx2: Fix bug in bnx2_free_tx_skbs().
In rare cases, bnx2x_free_tx_skbs() can unmap the wrong DMA address
when it gets to the last entry of the tx ring. We were not using
the proper macro to skip the last entry when advancing the tx index.
Reported-by: Zongyun Lai <zlai@vmware.com> Reviewed-by: Jeffrey Huang <huangjw@broadcom.com> Signed-off-by: Michael Chan <mchan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Tue, 10 Jul 2012 10:03:41 +0000 (10:03 +0000)]
IPoIB: fix skb truesize underestimatiom
Or Gerlitz reported triggering of WARN_ON_ONCE(delta < len); in
skb_try_coalesce()
This warning tracks drivers that incorrectly set skb->truesize
IPoIB indeed allocates a full page to store a fragment, but only
accounts in skb->truesize the used part of the page (frame length)
This patch fixes skb truesize underestimation, and
also fixes a performance issue, because RX skbs have not enough tailroom
to allow IP and TCP stacks to pull their header in skb linear part
without an expensive call to pskb_expand_head()
Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Or Gerlitz <ogerlitz@mellanox.com> Cc: Erez Shitrit <erezsh@mellanox.com> Cc: Shlomo Pongartz <shlomop@mellanox.com> Cc: Roland Dreier <roland@purestorage.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Amir Hanania [Mon, 9 Jul 2012 20:47:19 +0000 (20:47 +0000)]
net: Fix memory leak - vlan_info struct
In driver reload test there is a memory leak.
The structure vlan_info was not freed when the driver was removed.
It was not released since the nr_vids var is one after last vlan was removed.
The nr_vids is one, since vlan zero is added to the interface when the interface
is being set, but the vlan zero is not deleted at unregister.
Fix - delete vlan zero when we unregister the device.
Signed-off-by: Amir Hanania <amir.hanania@intel.com> Acked-by: John Fastabend <john.r.fastabend@intel.com> Tested-by: Aaron Brown <aaron.f.brown@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Rob Herring [Mon, 9 Jul 2012 14:16:08 +0000 (14:16 +0000)]
net: calxedaxgmac: fix hang on rx refill
Fix intermittent hangs in xgmac_rx_refill. If a ring buffer entry already
had an skb allocated, then xgmac_rx_refill would get stuck in a loop. This
can happen on a rx error when we just leave the skb allocated to the entry.
[ 7884.510000] INFO: rcu_preempt detected stall on CPU 0 (t=727315 jiffies)
[ 7884.510000] [<c0010a59>] (unwind_backtrace+0x1/0x98) from [<c006fd93>] (__rcu_pending+0x11b/0x2c4)
[ 7884.510000] [<c006fd93>] (__rcu_pending+0x11b/0x2c4) from [<c0070b95>] (rcu_check_callbacks+0xed/0x1a8)
[ 7884.510000] [<c0070b95>] (rcu_check_callbacks+0xed/0x1a8) from [<c0036abb>] (update_process_times+0x2b/0x48)
[ 7884.510000] [<c0036abb>] (update_process_times+0x2b/0x48) from [<c004e8fd>] (tick_sched_timer+0x51/0x94)
[ 7884.510000] [<c004e8fd>] (tick_sched_timer+0x51/0x94) from [<c0045527>] (__run_hrtimer+0x4f/0x1e8)
[ 7884.510000] [<c0045527>] (__run_hrtimer+0x4f/0x1e8) from [<c0046003>] (hrtimer_interrupt+0xd7/0x1e4)
[ 7884.510000] [<c0046003>] (hrtimer_interrupt+0xd7/0x1e4) from [<c00101d3>] (twd_handler+0x17/0x24)
[ 7884.510000] [<c00101d3>] (twd_handler+0x17/0x24) from [<c006be39>] (handle_percpu_devid_irq+0x59/0x114)
[ 7884.510000] [<c006be39>] (handle_percpu_devid_irq+0x59/0x114) from [<c0069aab>] (generic_handle_irq+0x17/0x2c)
[ 7884.510000] [<c0069aab>] (generic_handle_irq+0x17/0x2c) from [<c000cc8d>] (handle_IRQ+0x35/0x7c)
[ 7884.510000] [<c000cc8d>] (handle_IRQ+0x35/0x7c) from [<c033b153>] (__irq_svc+0x33/0xb8)
[ 7884.510000] [<c033b153>] (__irq_svc+0x33/0xb8) from [<c0244b06>] (xgmac_rx_refill+0x3a/0x140)
[ 7884.510000] [<c0244b06>] (xgmac_rx_refill+0x3a/0x140) from [<c02458ed>] (xgmac_poll+0x265/0x3bc)
[ 7884.510000] [<c02458ed>] (xgmac_poll+0x265/0x3bc) from [<c029fcbf>] (net_rx_action+0xc3/0x200)
[ 7884.510000] [<c029fcbf>] (net_rx_action+0xc3/0x200) from [<c0030cab>] (__do_softirq+0xa3/0x1bc)
Signed-off-by: Rob Herring <rob.herring@calxeda.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:35 +0000 (14:09 +0000)]
ll_temac: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set by the driver on packet recieve.
eth_type_trans already sets skb->dev to the proper value and it is not
referenced anywhere else in the dirver, thus making its setting unnecessary.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:34 +0000 (14:09 +0000)]
sunhme: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set during ring init and skb alloc in rx. It is
already being set to the proper value when eth_type_trans is called on packet
receive, and the skb->dev is not referenced anywhere else in the code.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:33 +0000 (14:09 +0000)]
sungem: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set by the driver's skb alloc routine (which is
called in init and during rx). It is already being set to the proper value when
eth_type_trans is called on packet receive, and the skb->dev is not referenced
anywhere else in the code.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:32 +0000 (14:09 +0000)]
sunbmac: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set during ring init and skb alloc in rx. It is
already being set to the proper value when eth_type_trans is called on packet
receive, and the skb->dev is not referenced anywhere else in the code.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:31 +0000 (14:09 +0000)]
qlge: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set by the driver on packet recieve.
eth_type_trans already sets skb->dev to the proper value and it is not
referenced anywhere else in the dirver, thus making its setting unnecessary.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Cc: Anirban Chakraborty <anirban.chakraborty@qlogic.com> Cc: Jitendra Kalsaria <jitendra.kalsaria@qlogic.com> Cc: Ron Mercer <ron.mercer@qlogic.com> Cc: linux-driver@qlogic.com Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:30 +0000 (14:09 +0000)]
qlcnic: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set before calling eth_type_trans.
eth_type_trans already sets skb->dev to the proper value, thus making this
unnecessary.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Cc: Anirban Chakraborty <anirban.chakraborty@qlogic.com> Cc: Sony Chacko <sony.chacko@qlogic.com> Cc: linux-driver@qlogic.com Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:29 +0000 (14:09 +0000)]
ksz884x: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set during ring init. It is already being set
to the proper value when eth_type_trans is called on packet receive, and the
skb->dev is not referenced anywhere else in the code.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:28 +0000 (14:09 +0000)]
lantiq_etop: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set before calling eth_type_trans.
eth_type_trans already sets skb->dev to the proper value, thus making this
unnecessary.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:27 +0000 (14:09 +0000)]
netxen: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set by the driver on packet recieve.
eth_type_trans already sets skb->dev to the proper value and it is not
referenced anywhere else in the dirver, thus making its setting unnecessary.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Cc: Sony Chacko <sony.chacko@qlogic.com> Cc: Rajesh Borundia <rajesh.borundia@qlogic.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:26 +0000 (14:09 +0000)]
enic: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set after calling eth_type_trans.
eth_type_trans already sets skb->dev to the proper value, thus making this
unnecessary.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Cc: Christian Benvenuti <benve@cisco.com> Cc: Roopa Prabhu <roprabhu@cisco.com> Cc: Neel Patel <neepatel@cisco.com> Cc: Nishank Trivedi <nistrive@cisco.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Jon Mason [Mon, 9 Jul 2012 14:09:25 +0000 (14:09 +0000)]
lance: remove unnecessary setting of skb->dev
skb->dev is being unnecessarily set during ring init. It is already being set
to the proper value when eth_type_trans is called on packet receive, and the
skb->dev is not referenced anywhere else in the code.
Signed-off-by: Jon Mason <jdmason@kudzu.us> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Tue, 10 Jul 2012 19:05:57 +0000 (19:05 +0000)]
ipv6: optimize ipv6 addresses compares
On 64 bit arches having efficient unaligned accesses (eg x86_64) we can
use long words to reduce number of instructions for free.
Joe Perches suggested to change ipv6_masked_addr_cmp() to return a bool
instead of 'int', to make sure ipv6_masked_addr_cmp() cannot be used
in a sorting function.
Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Ben Hutchings [Tue, 10 Jul 2012 10:56:59 +0000 (10:56 +0000)]
drivers/net/ethernet: Fix non-kernel-doc comments with kernel-doc start markers
Convert doxygen (or similar) formatted comments to kernel-doc or
unformatted comment. Delete a few that are content-free.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Ben Hutchings [Tue, 10 Jul 2012 10:56:00 +0000 (10:56 +0000)]
drivers/net/ethernet: Fix (nearly-)kernel-doc comments for various functions
Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches. Delete
a few that are content-free.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
David S. Miller [Wed, 11 Jul 2012 05:53:57 +0000 (22:53 -0700)]
Merge branch 'metrics_restructure'
This patch series works towards the goal of minimizing the amount
of things that can change in an ipv4 route.
In a regime where the routing cache is removed, route changes will
lead to cloning in the FIB tables or similar.
The largest trigger of route metrics writes, TCP, now has it's own
cache of dynamic metric state. The timewait timestamps are stored
there now as well.
As a result of that, pre-cowing metrics is no longer necessary,
and therefore FLOWI_FLAG_PRECOW_METRICS is removed.
Redirect and PMTU handling is moved back into the ipv4 routes. I'm
sorry for all the headaches trying to do this in the inetpeer has
caused, it was the wrong approach for sure.
Since metrics become read-only for ipv4 we no longer need the inetpeer
hung off of the ipv4 routes either. So those disappear too.
Also, timewait sockets no longer need to hold onto an inetpeer either.
After this series, we still have some details to resolve wrt. PMTU and
redirects for a route-cache-less system:
1) With just the plain route cache removal, PMTU will continue to
work mostly fine. This is because of how the local route users
call down into the PMTU update code with the route they already
hold.
However, if we wish to cache pre-computed routes in fib_info
nexthops (which we want for performance), then we need to add
route cloning for PMTU events.
2) Redirects require more work. First, redirects must be changed to
be handled like PMTU. Wherein we call down into the sockets and
other entities, and then they call back into the routing code with
the route they were using.
So we'll be adding an ->update_nexthop() method alongside
->update_pmtu().
And then, like for PMTU, we'll need cloning support once we start
caching routes in the fib_info nexthops.
But that's it, we can completely pull the trigger and remove the
routing cache with minimal disruptions.
As it is, this patch series alone helps a lot of things. For one,
routing cache entry creation should be a lot faster, because we no
longer do inetpeer lookups (even to check if an entry exists).
This patch series also opens the door for non-DST_HOST ipv4 routes,
because nothing fundamentally cares about rt->rt_dst any more. It
can be removed with the base routing cache removal patch. In fact,
that was the primary goal of this patch series.
Signed-off-by: David S. Miller <davem@davemloft.net>
projects / linux-beck.git / log