In order to compute the features for other offloads (primarily
scatter/gather), we need to first check the ability of the NIC to
offload the checksum for the packet. Since we have already computed
this, we can directly use the result instead of figuring it out
again.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This switches skb_need_linearize() to use the features that have
been centrally computed. In doing so, this fixes a problem where
scatter/gather should not be used because the card does not support
checksum offloading on that type of packet. On device registration
we only check that some form of checksum offloading is available if
scatter/gatther is enabled but we must also check at transmission
time. Examples of this include IPv6 or vlan packets on a NIC that
only supports IPv4 offloading.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This switches dev_gso_segment() to use the device features computed
by the centralized routine. In doing so, it fixes a problem where
it would always use dev->features, instead of those appropriate
to the number of vlan tags if any are present.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that there is a single function that can compute the device
features relevant to a packet, we don't want to run it for each
offload. This converts netif_needs_gso() to take the features
of the device, rather than computing them itself.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
netif_get_vlan_features() is currently only used by netif_needs_gso(),
so it only concerns itself with GSO features. However, several other
places also should take into account the contents of the packet when
deciding whether to offload to hardware. This generalizes the function
to return features about all of the various forms of offloading. Since
offloads tend to be linked together, this avoids duplicating the logic
in each location (i.e. the scatter/gather code also needs the checksum
logic).
Suggested-by: Michał Mirosław <mirqus@gmail.com>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently only have software fallback for one type of checksum: the
TCP/UDP one's complement. This means that a protocol that uses hardware
offloading for a different type of checksum (FCoE, SCTP) must directly
check the device's features and do the right thing ahead of time. By
the time we get to dev_can_checksum(), we're only deciding whether to
apply the one algorithm in software or hardware. NETIF_F_HW_CSUM has the
same capabilities as the software version, so we should always use it if
present. The primary advantage of this is multiply tagged vlans can use
hardware checksumming.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix new kernel-doc notation warning in net/core/filter.c:
Warning(net/core/filter.c:172): No description found for parameter 'fentry'
Warning(net/core/filter.c:172): Excess function parameter 'filter' description in 'sk_run_filter'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Due to NLM_F_DUMP is composed of two bits, NLM_F_ROOT | NLM_F_MATCH,
when doing "if (x & NLM_F_DUMP)", it tests for _either_ of the bits
being set. Because NLM_F_MATCH's value overlaps with NLM_F_EXCL,
non-dump requests with NLM_F_EXCL set are mistaken as dump requests.
Substitute the condition to test for _all_ bits being set.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'for-2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: (33 commits)
usb: don't use flush_scheduled_work()
speedtch: don't abuse struct delayed_work
media/video: don't use flush_scheduled_work()
media/video: explicitly flush request_module work
ioc4: use static work_struct for ioc4_load_modules()
init: don't call flush_scheduled_work() from do_initcalls()
s390: don't use flush_scheduled_work()
rtc: don't use flush_scheduled_work()
mmc: update workqueue usages
mfd: update workqueue usages
dvb: don't use flush_scheduled_work()
leds-wm8350: don't use flush_scheduled_work()
mISDN: don't use flush_scheduled_work()
macintosh/ams: don't use flush_scheduled_work()
vmwgfx: don't use flush_scheduled_work()
tpm: don't use flush_scheduled_work()
sonypi: don't use flush_scheduled_work()
hvsi: don't use flush_scheduled_work()
xen: don't use flush_scheduled_work()
gdrom: don't use flush_scheduled_work()
...
Fixed up trivial conflict in drivers/media/video/bt8xx/bttv-input.c
as per Tejun.
Leonardo Chiquitto found poll() could block forever on tcp sockets and
Urgent data was received, if the event flag only contains POLLPRI.
He did a bisection and found commit 4938d7e023 (poll: avoid extra
wakeups in select/poll) was the source of the problem.
Problem is TCP sockets use standard sock_def_readable() function for
their sk_data_ready() handler, and sock_def_readable() doesnt signal
POLLPRI.
Only TCP is affected by the problem. Adding POLLPRI to the list of flags
might trigger unnecessary schedules, but URGENT handling is such a
seldom used feature this seems a good compromise.
Thanks a lot to Leonardo for providing the bisection result and a test
program as well.
Reference : http://www.spinics.net/lists/netdev/msg151793.html
Reported-and-bisected-by: Leonardo Chiquitto <leonardo.lists@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 4465b46900.
Conflicts:
net/ipv4/fib_frontend.c
As reported by Ben Greear, this causes regressions:
> Change 4465b46900 caused rules
> to stop matching the input device properly because the
> FLOWI_FLAG_MATCH_ANY_IIF is always defined in ip_dev_find().
>
> This breaks rules such as:
>
> ip rule add pref 512 lookup local
> ip rule del pref 0 lookup local
> ip link set eth2 up
> ip -4 addr add 172.16.0.102/24 broadcast 172.16.0.255 dev eth2
> ip rule add to 172.16.0.102 iif eth2 lookup local pref 10
> ip rule add iif eth2 lookup 10001 pref 20
> ip route add 172.16.0.0/24 dev eth2 table 10001
> ip route add unreachable 0/0 table 10001
>
> If you had a second interface 'eth0' that was on a different
> subnet, pinging a system on that interface would fail:
>
> [root@ct503-60 ~]# ping 192.168.100.1
> connect: Invalid argument
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can translate pseudo load instructions at filter check time to
dedicated instructions to speed up filtering and avoid one switch().
libpcap currently uses SKF_AD_PROTOCOL, but custom filters probably use
other ancillary accesses.
Note : I made the assertion that ancillary data was always accessed with
BPF_LD|BPF_?|BPF_ABS instructions, not with BPF_LD|BPF_?|BPF_IND ones
(offset given by K constant, not by K + X register)
On x86_64, this saves a few bytes of text :
# size net/core/filter.o.*
text data bss dec hex filename
4864 0 0 4864 1300 net/core/filter.o.new
4944 0 0 4944 1350 net/core/filter.o.old
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Le vendredi 17 décembre 2010 à 10:26 +0100, Eric Dumazet a écrit :
>
> I think we can add this after latest Changli patch :
>
> He does one skb_clone() before calling the sniffers.
> We could set timestamp on this clone, instead of original skb.
>
> Problem solved.
>
[PATCH net-next-2.6] net: timestamp cloned packet in dev_queue_xmit_nit
Now we do one clone of skb if at least one sniffer might take packet,
we also can do the skb timestamping on the clone and let original packet
unchanged.
This is a generalization of commit 8caf153974 (net: sch_netem: Fix an
inconsistency in ingress netem timestamps.)
This way, we can have a good idea when packets are delivered to our
stack (tcpdump -i ifb0), while a tcpdump on original device gives
timestamps right before ingressing.
This also speedup our stack, avoiding taking timestamps if not needed.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Changli Gao <xiaosuo@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jarek Poplawski <jarkao2@gmail.com>
Acked-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove "pktgen: " prefix string from one pr_info.
pr_fmt adds it, so this is a duplicate.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In dev_queue_xmit_nit(), we have to clone skbs as we need to mangle skbs,
however, we don't need to clone skbs for all the packet_types.
Except for the first packet_type, we increase skb->users instead of
skb_clone().
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Replace skb->csum_start - skb_headroom(skb) with skb_checksum_start_offset().
Note for usb/smsc95xx: skb->data - skb->head == skb_headroom(skb).
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
Special care is taken inside sk_port_alloc to avoid overwriting
skc_node/skc_nulls_node. We should also avoid overwriting
skc_bind_node/skc_portaddr_node.
The patch fixes the following crash:
BUG: unable to handle kernel paging request at fffffffffffffff0
IP: [<ffffffff812ec6dd>] udp4_lib_lookup2+0xad/0x370
[<ffffffff812ecc22>] __udp4_lib_lookup+0x282/0x360
[<ffffffff812ed63e>] __udp4_lib_rcv+0x31e/0x700
[<ffffffff812bba45>] ? ip_local_deliver_finish+0x65/0x190
[<ffffffff812bbbf8>] ? ip_local_deliver+0x88/0xa0
[<ffffffff812eda35>] udp_rcv+0x15/0x20
[<ffffffff812bba45>] ip_local_deliver_finish+0x65/0x190
[<ffffffff812bbbf8>] ip_local_deliver+0x88/0xa0
[<ffffffff812bb2cd>] ip_rcv_finish+0x32d/0x6f0
[<ffffffff8128c14c>] ? netif_receive_skb+0x99c/0x11c0
[<ffffffff812bb94b>] ip_rcv+0x2bb/0x350
[<ffffffff8128c14c>] netif_receive_skb+0x99c/0x11c0
Signed-off-by: Leonard Crestez <lcrestez@ixiacom.com>
Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add dev_close_many and dev_deactivate_many to factorize another
sync-rcu operation on the netdevice unregister path.
$ modprobe dummy numdummies=10000
$ ip link set dev dummy* up
$ time rmmod dummy
Without the patch With the patch
real 0m 24.63s real 0m 5.15s
user 0m 0.00s user 0m 0.00s
sys 0m 6.05s sys 0m 5.14s
Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move the calcualation of the Tx hash for a given hash range into a separate
function and define the skb_tx_hash(), which calculates a Tx hash for a
[0; dev->real_num_tx_queues - 1] hash values range, using this
function (__skb_tx_hash()).
Signed-off-by: Vladislav Zolotarov <vladz@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
cancel_rearming_delayed_work[queue]() has been superceded by
cancel_delayed_work_sync() quite some time ago. Convert all the
in-kernel users. The conversions are completely equivalent and
trivial.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: "David S. Miller" <davem@davemloft.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Jeff Garzik <jgarzik@pobox.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: netdev@vger.kernel.org
Cc: Anton Vorontsov <cbou@mail.ru>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Neil Brown <neilb@suse.de>
Cc: Alex Elder <aelder@sgi.com>
Cc: xfs-masters@oss.sgi.com
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Pekka Enberg <penberg@cs.helsinki.fi>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: netfilter-devel@vger.kernel.org
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: linux-nfs@vger.kernel.org
After commit c1f19b51d1 (net: support time stamping in phy devices.),
kernel might crash if CONFIG_NETWORK_PHY_TIMESTAMPING=y and
skb_defer_rx_timestamp() handles a packet without an ethernet header.
Fixes kernel bugzilla #24102
Reference: https://bugzilla.kernel.org/show_bug.cgi?id=24102
Reported-and-tested-by: Andrew Watts <akwatts@ymail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While an interface is down, many implementations of
ethtool_ops::get_link, including the default, ethtool_op_get_link(),
will report the last link state seen while the interface was up. In
general the current physical link state is not available if the
interface is down.
Define ETHTOOL_GLINK to reflect whether the interface *and* any
physical port have a working link, and consistently return 0 when the
interface is down.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We know for sure pktgen is going to write skb->data right after
*_alloc_skb, causing unnecessary cache misses.
Idea is to add a prefetchw() call to prefetch the first cache line
indicated by skb->data. On systems with Adjacent Cache Line Prefetch,
it's probably two cache lines are prefetched.
With this patch, pktgen on Intel SR1625 server with two E5530
quad-core processors and a single ixgbe-based NIC went from 8.63Mpps
to 9.03Mpps, with 4.6% improvement.
Signed-off-by: Junchang Wang <junchangwang@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__load_pointer() checks data we fetch from skb is included in head
portion, but assumes we fetch one byte, instead of up to four.
This wont crash because we have extra bytes (struct skb_shared_info)
after head, but this can read uninitialized bytes.
Fix this using size of the data (1, 2, 4 bytes) in the test.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Followup of commit b178bb3dfc (net: reorder struct sock fields)
Optimize INET input path a bit further, by :
1) moving sk_refcnt close to sk_lock.
This reduces number of dirtied cache lines by one on 64bit arches (and
64 bytes cache line size).
2) moving inet_daddr & inet_rcv_saddr at the beginning of sk
(same cache line than hash / family / bound_dev_if / nulls_node)
This reduces number of accessed cache lines in lookups by one, and dont
increase size of inet and timewait socks.
inet and tw sockets now share same place-holder for these fields.
Before patch :
offsetof(struct sock, sk_refcnt) = 0x10
offsetof(struct sock, sk_lock) = 0x40
offsetof(struct sock, sk_receive_queue) = 0x60
offsetof(struct inet_sock, inet_daddr) = 0x270
offsetof(struct inet_sock, inet_rcv_saddr) = 0x274
After patch :
offsetof(struct sock, sk_refcnt) = 0x44
offsetof(struct sock, sk_lock) = 0x48
offsetof(struct sock, sk_receive_queue) = 0x68
offsetof(struct inet_sock, inet_daddr) = 0x0
offsetof(struct inet_sock, inet_rcv_saddr) = 0x4
compute_score() (udp or tcp) now use a single cache line per ignored
item, instead of two.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid some atomic ops on dst refcount, calling dev_queue_xmit_nit()
after skb_dst_drop() in dev_hard_start_xmit().
When queueing a packet into af_packet socket, we drop dst anyway.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk_run_filter() doesnt write on skb, change its prototype to reflect
this.
Fix two af_packet comments.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Le dimanche 05 décembre 2010 à 09:19 +0100, Eric Dumazet a écrit :
> Hmm..
>
> If somebody can explain why RTNL is held in arp_ioctl() (and therefore
> in arp_req_delete()), we might first remove RTNL use in arp_ioctl() so
> that your patch can be applied.
>
> Right now it is not good, because RTNL wont be necessarly held when you
> are going to call arp_invalidate() ?
While doing this analysis, I found a refcount bug in llc, I'll send a
patch for net-2.6
Meanwhile, here is the patch for net-next-2.6
Your patch then can be applied after mine.
Thanks
[PATCH] net: RCU conversion of dev_getbyhwaddr() and arp_ioctl()
dev_getbyhwaddr() was called under RTNL.
Rename it to dev_getbyhwaddr_rcu() and change all its caller to now use
RCU locking instead of RTNL.
Change arp_ioctl() to use RCU instead of RTNL locking.
Note: this fix a dev refcount bug in llc
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The dev field of ingress queue is forgot to initialized, then NULL
pointer dereference happens in qdisc_alloc().
Move inits of tx queues to netif_alloc_netdev_queues().
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hi,
This patch fixes a typo in net/core/datagram.c and in net/sctp/socket.c
Regards,
David Shwartz
Signed-off-by: David Shwartz <dshwatrz@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We added some security checks in commit 57fe93b374
(filter: make sure filters dont read uninitialized memory) to close a
potential leak of kernel information to user.
This added a potential extra cost at run time, while we can perform a
check of the filter itself, to make sure a malicious user doesnt try to
abuse us.
This patch adds a check_loads() function, whole unique purpose is to
make this check, allocating a temporary array of mask. We scan the
filter and propagate a bitmask information, telling us if a load M(K) is
allowed because a previous store M(K) is guaranteed. (So that
sk_run_filter() can possibly not read unitialized memory)
Note: this can uncover application bug, denying a filter attach,
previously allowed.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: Changli Gao <xiaosuo@gmail.com>
Acked-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add SKF_AD_RXHASH and SKF_AD_CPU to filter ancillary mechanism,
to be able to build advanced filters.
This can help spreading packets on several sockets with a fast
selection, after RPS dispatch to N cpus for example, or to catch a
percentage of flows in one queue.
tcpdump -s 500 "cpu = 1" :
[0] ld CPU
[1] jeq #1 jt 2 jf 3
[2] ret #500
[3] ret #0
# take 12.5 % of flows (average)
tcpdump -s 1000 "rxhash & 7 = 2" :
[0] ld RXHASH
[1] and #7
[2] jeq #2 jt 3 jf 4
[3] ret #1000
[4] ret #0
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Rui <wirelesser@gmail.com>
Acked-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
NETIF_F_HW_CSUM is a superset of NETIF_F_IP_CSUM+NETIF_F_IPV6_CSUM, but
some drivers miss the difference. Fix this and also fix UFO dependency
on checksumming offload as it makes the same mistake in assumptions.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Jon Mason <jon.mason@exar.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov tried to fix a race between sk_filter_(de|at)tach and
sk_clone() in commit 47e958eac2
Problem is we can have several clones sharing a common sk_filter, and
these clones might want to sk_filter_attach() their own filters at the
same time, and can overwrite old_filter->rcu, corrupting RCU queues.
We can not use filter->rcu without being sure no other thread could do
the same thing.
Switch code to a more conventional ref-counting technique : Do the
atomic decrement immediately and queue one rcu call back when last
reference is released.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb head being allocated by kmalloc(), it might be larger than what
actually requested because of discrete kmem caches sizes. Before
reallocating a new skb head, check if the current one has the needed
extra size.
Do this check only if skb head is not shared.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This will also improve handling of ipv6 tcp socket request
backlog when syncookies are not enabled. When backlog
becomes very deep, last quarter of backlog is limited to
validated destinations. Previously only ipv4 implemented
this logic, but now ipv6 does too.
Now we are only one step away from enabling timewait
recycling for ipv6, and that step is simply filling in
the implementation of tcp_v6_get_peer() and
tcp_v6_tw_get_peer().
Signed-off-by: David S. Miller <davem@davemloft.net>
Allocate qdisc memory according to NUMA properties of cpus included in
xps map.
To be effective, qdisc should be (re)setup after changes
of /sys/class/net/eth<n>/queues/tx-<n>/xps_cpus
I added a numa_node field in struct netdev_queue, containing NUMA node
if all cpus included in xps_cpus share same node, else -1.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid sparse warnings : add __rcu annotations and use
rcu_dereference_protected() where necessary.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
store_xps_map() allocates maps that are used by single cpu, it makes
sense to use NUMA allocations.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds XPS_CONFIG option to enable and disable XPS. This is
done in the same manner as RPS_CONFIG. This is also fixes build
failure in XPS code when SMP is not enabled.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When testing struct netdev_queue state against FROZEN bit, we also test
XOFF bit. We can test both bits at once and save some cycles.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As David pointed out correctly, updates to af-specific attributes
are currently not atomic. If multiple changes are requested and
one of them fails, previous updates may have been applied already
leaving the link behind in a undefined state.
This patch splits the function parse_link_af() into two functions
validate_link_af() and set_link_at(). validate_link_af() is placed
to validate_linkmsg() check for errors as early as possible before
any changes to the link have been made. set_link_af() is called to
commit the changes later.
This method is not fail proof, while it is currently sufficient
to make set_link_af() inerrable and thus 100% atomic, the
validation function method will not be able to detect all error
scenarios in the future, there will likely always be errors
depending on states which are f.e. not protected by rtnl_mutex
and thus may change between validation and setting.
Also, instead of silently ignoring unknown address families and
config blocks for address families which did not register a set
function the errors EAFNOSUPPORT respectively EOPNOSUPPORT are
returned to avoid comitting 4 out of 5 update requests without
notifying the user.
Signed-off-by: Thomas Graf <tgraf@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements transmit packet steering (XPS) for multiqueue
devices. XPS selects a transmit queue during packet transmission based
on configuration. This is done by mapping the CPU transmitting the
packet to a queue. This is the transmit side analogue to RPS-- where
RPS is selecting a CPU based on receive queue, XPS selects a queue
based on the CPU (previously there was an XPS patch from Eric
Dumazet, but that might more appropriately be called transmit completion
steering).
Each transmit queue can be associated with a number of CPUs which will
use the queue to send packets. This is configured as a CPU mask on a
per queue basis in:
/sys/class/net/eth<n>/queues/tx-<n>/xps_cpus
The mappings are stored per device in an inverted data structure that
maps CPUs to queues. In the netdevice structure this is an array of
num_possible_cpu structures where each structure holds and array of
queue_indexes for queues which that CPU can use.
The benefits of XPS are improved locality in the per queue data
structures. Also, transmit completions are more likely to be done
nearer to the sending thread, so this should promote locality back
to the socket on free (e.g. UDP). The benefits of XPS are dependent on
cache hierarchy, application load, and other factors. XPS would
nominally be configured so that a queue would only be shared by CPUs
which are sharing a cache, the degenerative configuration woud be that
each CPU has it's own queue.
Below are some benchmark results which show the potential benfit of
this patch. The netperf test has 500 instances of netperf TCP_RR test
with 1 byte req. and resp.
bnx2x on 16 core AMD
XPS (16 queues, 1 TX queue per CPU) 1234K at 100% CPU
No XPS (16 queues) 996K at 100% CPU
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In dev_pick_tx, don't do work in calculating queue
index or setting
the index in the sock unless the device has more than one queue. This
allows the sock to be set only with a queue index of a multi-queue
device which is desirable if device are stacked like in a tunnel.
We also allow the mapping of a socket to queue to be changed. To
maintain in order packet transmission a flag (ooo_okay) has been
added to the sk_buff structure. If a transport layer sets this flag
on a packet, the transmit queue can be changed for the socket.
Presumably, the transport would set this if there was no possbility
of creating OOO packets (for instance, there are no packets in flight
for the socket). This patch includes the modification in TCP output
for setting this flag.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Lower SCM_MAX_FD from 255 to 253 so that allocations for scm_fp_list are
halved. (commit f8d570a4 added two pointers in this structure)
scm_fp_dup() should not copy whole structure (and trigger kmemcheck
warnings), but only the used part. While we are at it, only allocate
needed size.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jesse Gross