This patch adds support for a skb_head_is_locked helper function. It is
meant to be used any time we are considering transferring the head from
skb->head to a paged frag. If the head is locked it means we cannot remove
the head from the skb so it must be copied or we must take the skb as a
whole.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
GRO is very optimistic in skb truesize estimates, only taking into
account the used part of fragments.
Be conservative, and use more precise computation, so that bloated GRO
skbs can be collapsed eventually.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This change is meant ot prevent stealing the skb->head to use as a page in
the event that the skb->head was cloned. This allows the other clones to
track each other via shinfo->dataref.
Without this we break down to two methods for tracking the reference count,
one being dataref, the other being the page count. As a result it becomes
difficult to track how many references there are to skb->head.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
TCP or UDP stacks have big enough latencies that prefetching next
pointer is worth it.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__skb_splice_bits() can check if skb to be spliced has its skb->head
mapped to a page fragment, instead of a kmalloc() area.
If so we can avoid a copy of the skb head and get a reference on
underlying page.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Matt Carlson <mcarlson@broadcom.com>
Cc: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
GRO can check if skb to be merged has its skb->head mapped to a page
fragment, instead of a kmalloc() area.
We 'upgrade' skb->head as a fragment in itself
This avoids the frag_list fallback, and permits to build true GRO skb
(one sk_buff and up to 16 fragments), using less memory.
This reduces number of cache misses when user makes its copy, since a
single sk_buff is fetched.
This is a followup of patch "net: allow skb->head to be a page fragment"
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Matt Carlson <mcarlson@broadcom.com>
Cc: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb->head is currently allocated from kmalloc(). This is convenient but
has the drawback the data cannot be converted to a page fragment if
needed.
We have three spots were it hurts :
1) GRO aggregation
When a linear skb must be appended to another skb, GRO uses the
frag_list fallback, very inefficient since we keep all struct sk_buff
around. So drivers enabling GRO but delivering linear skbs to network
stack aren't enabling full GRO power.
2) splice(socket -> pipe).
We must copy the linear part to a page fragment.
This kind of defeats splice() purpose (zero copy claim)
3) TCP coalescing.
Recently introduced, this permits to group several contiguous segments
into a single skb. This shortens queue lengths and save kernel memory,
and greatly reduce probabilities of TCP collapses. This coalescing
doesnt work on linear skbs (or we would need to copy data, this would be
too slow)
Given all these issues, the following patch introduces the possibility
of having skb->head be a fragment in itself. We use a new skb flag,
skb->head_frag to carry this information.
build_skb() is changed to accept a frag_size argument. Drivers willing
to provide a page fragment instead of kmalloc() data will set a non zero
value, set to the fragment size.
Then, on situations we need to convert the skb head to a frag in itself,
we can check if skb->head_frag is set and avoid the copies or various
fallbacks we have.
This means drivers currently using frags could be updated to avoid the
current skb->head allocation and reduce their memory footprint (aka skb
truesize). (thats 512 or 1024 bytes saved per skb). This also makes
bpf/netfilter faster since the 'first frag' will be part of skb linear
part, no need to copy data.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Cc: Ben Hutchings <bhutchings@solarflare.com>
Cc: Matt Carlson <mcarlson@broadcom.com>
Cc: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixed a coding style issue relating to spaces
in net/core/sock.c
Signed-off-by: Jeffrin Jose <ahiliation@yahoo.co.in>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use min_t()/max_t() macros, reformat two comments, use !!test_bit() to
match !!sock_flag()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
read only, so change it to const.
Signed-off-by: Shan Wei <davidshan@tencent.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix merge between commit 3adadc08cc ("net ax25: Reorder ax25_exit to
remove races") and commit 0ca7a4c87d ("net ax25: Simplify and
cleanup the ax25 sysctl handling")
The former moved around the sysctl register/unregister calls, the
later simply removed them.
With help from Stephen Rothwell.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 35f3d14db (pipe: add support for shrinking and growing pipes)
added a slowdown for splice(socket -> pipe), as we might grow the spd
used in skb_splice_bits() for each skb we process in splice() syscall.
Its not needed since skb lengths are capped. The default on-stack arrays
are more than enough.
Use MAX_SKB_FRAGS instead of PIPE_DEF_BUFFERS to describe the reasonable
limit per skb.
Add coalescing support to help splicing of GRO skbs built from linear
skbs (linked into frag_list)
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
sk_add_backlog() & sk_rcvqueues_full() hard coded sk_rcvbuf as the
memory limit. We need to make this limit a parameter for TCP use.
No functional change expected in this patch, all callers still using the
old sk_rcvbuf limit.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
splice() from socket to pipe needs linear_to_page() helper to transfert
skb header to part of page.
We can reset the offset in the current sk->sk_sndmsg_page if we are the
last user of the page.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It seems there is a logic error in trace_drop_common(), since we store
only 64 drops, even if they are from same location.
This fix is a one liner, but we probably need more work to avoid useless
atomic dec/inc
Now I can watch 1 Mpps drops through dropwatch...
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Name them in a "backward compatible" manner, i.e. reuse or not
are still 1 and 0 respectively. The reuse value of 2 means that
the socket with it will forcibly reuse everyone else's port.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We don't use struct ctl_path anymore so delete the exported constants.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This results in code with less boiler plate that is a bit easier
to read.
Additionally stops us from using compatibility code in the sysctl
core, hastening the day when the compatibility code can be removed.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Using an ascii path to register_net_sysctl as opposed to the slightly
awkward ctl_path allows for much simpler code.
We no longer need to malloc dev_name to keep it alive the length of our
sysctl register instead we can use a small temporary buffer on the
stack.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On the next line we register the net_core_table in net/core which
creates the directory and ensures it exists.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This makes it clearer which sysctls are relative to your current network
namespace.
This makes it a little less error prone by not exposing sysctls for the
initial network namespace in other namespaces.
This is the same way we handle all of our other network interfaces to
userspace and I can't honestly remember why we didn't do this for
sysctls right from the start.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
register_sysctl_rotable never caught on as an interesting way to
register sysctls. My take on the situation is that what we want are
sysctls that we can only see in the initial network namespace. What we
have implemented with register_sysctl_rotable are sysctls that we can
see in all of the network namespaces and can only change in the initial
network namespace.
That is a very silly way to go. Just register the network sysctls
in the initial network namespace and we don't have any weird special
cases to deal with.
The sysctls affected are:
/proc/sys/net/ipv4/ipfrag_secret_interval
/proc/sys/net/ipv4/ipfrag_max_dist
/proc/sys/net/ipv6/ip6frag_secret_interval
/proc/sys/net/ipv6/mld_max_msf
I really don't expect anyone will miss them if they can't read them in a
child user namespace.
CC: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Acked-by: Pavel Emelyanov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As part of GRO processing, merged skbs should be consumed, not freed, to
not confuse dropwatch/drop_monitor.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When we need to clone skb, we dont drop a packet.
Call consume_skb() to not confuse dropwatch.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/sysctl_net_core.c: In function ‘sysctl_core_init’:
net/core/sysctl_net_core.c:259: error: implicit declaration of function ‘kmemleak_not_leak’
with same error in net/ipv4/route.c
Signed-off-by: Shan Wei <davidshan@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ops_init should free the net_generic data on
init failure and __register_pernet_operations should not
call ops_free when NET_NS is not enabled.
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is useful to be able to monitor for FDB events in user space.
This patch adds support to generate netlink events when a change
is made to a device supporting the FDB ops.
This brings embedded switches inline with the SW net/bridge which
triggers events on FDB updates as well.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds a generic dump routine drivers can call. It
should be sufficient to handle any bridging model that
uses the unicast address list. This should be most SR-IOV
enabled NICs.
v2: return error on nlmsg_put and use -EMSGSIZE instead
of -ENOMEM this is inline other usages
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds a dev_uc_add_excl() and dev_mc_add_excl() calls
similar to the original dev_{uc|mc}_add() except it sets
the global bit and returns -EEXIST for duplicat entires.
This is useful for drivers that support SR-IOV, macvlan
devices and any other devices that need to manage the
unicast and multicast lists.
v2: fix typo UNICAST should be MULTICAST in dev_mc_add_excl()
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds two new flags NTF_MASTER and NTF_SELF that can
now be used to specify where PF_BRIDGE netlink commands should
be sent. NTF_MASTER sends the commands to the 'dev->master'
device for parsing. Typically this will be the linux net/bridge,
or open-vswitch devices. Also without any flags set the command
will be handled by the master device as well so that current user
space tools continue to work as expected.
The NTF_SELF flag will push the PF_BRIDGE commands to the
device. In the basic example below the commands are then parsed
and programmed in the embedded bridge.
Note if both NTF_SELF and NTF_MASTER bits are set then the
command will be sent to both 'dev->master' and 'dev' this allows
user space to easily keep the embedded bridge and software bridge
in sync.
There is a slight complication in the case with both flags set
when an error occurs. To resolve this the rtnl handler clears
the NTF_ flag in the netlink ack to indicate which sets completed
successfully. The add/del handlers will abort as soon as any
error occurs.
To support this new net device ops were added to call into
the device and the existing bridging code was refactored
to use these. There should be no required changes in user space
to support the current bridge behavior.
A basic setup with a SR-IOV enabled NIC looks like this,
veth0 veth2
| |
------------
| bridge0 | <---- software bridging
------------
/
/
ethx.y ethx
VF PF
\ \ <---- propagate FDB entries to HW
\ \
--------------------
| Embedded Bridge | <---- hardware offloaded switching
--------------------
In this case the embedded bridge must be managed to allow 'veth0'
to communicate with 'ethx.y' correctly. At present drivers managing
the embedded bridge either send frames onto the network which
then get dropped by the switch OR the embedded bridge will flood
these frames. With this patch we have a mechanism to manage the
embedded bridge correctly from user space. This example is specific
to SR-IOV but replacing the VF with another PF or dropping this
into the DSA framework generates similar management issues.
Examples session using the 'br'[1] tool to add, dump and then
delete a mac address with a new "embedded" option and enabled
ixgbe driver:
# br fdb add 22:35:19:ac:60:59 dev eth3
# br fdb
port mac addr flags
veth0 22:35:19:ac:60:58 static
veth0 9a:5f:81:f7:f6:ec local
eth3 00:1b:21:55:23:59 local
eth3 22:35:19:ac:60:59 static
veth0 22:35:19:ac:60:57 static
#br fdb add 22:35:19:ac:60:59 embedded dev eth3
#br fdb
port mac addr flags
veth0 22:35:19:ac:60:58 static
veth0 9a:5f:81:f7:f6:ec local
eth3 00:1b:21:55:23:59 local
eth3 22:35:19:ac:60:59 static
veth0 22:35:19:ac:60:57 static
eth3 22:35:19:ac:60:59 local embedded
#br fdb del 22:35:19:ac:60:59 embedded dev eth3
I added a couple lines to 'br' to set the flags correctly is all. It
is my opinion that the merit of this patch is now embedded and SW
bridges can both be modeled correctly in user space using very nearly
the same message passing.
[1] 'br' tool was published as an RFC here and will be renamed 'bridge'
http://patchwork.ozlabs.org/patch/117664/
Thanks to Jamal Hadi Salim, Stephen Hemminger and Ben Hutchings for
valuable feedback, suggestions, and review.
v2: fixed api descriptions and error case with both NTF_SELF and
NTF_MASTER set plus updated patch description.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
neigh_table_init_no_netlink() is only used in net/core/neighbour.c file.
Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change get_tx_queues, drop unsused arg/return value real_tx_queues,
and use return by value (with error) rather than call by reference.
Probably bonding should just change to LLTX and the whole get_tx_queues
API could disappear!
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull in the 'net' tree to get CAIF bug fixes upon which
the following set of CAIF feature patches depend.
Signed-off-by: David S. Miller <davem@davemloft.net>
We already synthesize events in register_netdevice_notifier and synthesizing
events in unregister_netdevice_notifier allows to us remove the need for
special case cleanup code.
This change should be safe as it adds no new cases for existing callers
of unregiser_netdevice_notifier to handle.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixed coding style issues in net/core/utils.c
in relation with braces placement.
Signed-off-by: Jeffrin Jose <ahiliation@yahoo.co.in>
Signed-off-by: David S. Miller <davem@davemloft.net>
Changed net/core/net-sysfs.c: netdev_store() to use kstrtoul()
instead of obsolete simple_strtoul().
Signed-off-by: Shuah Khan <shuahkhan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Marc Merlin reported many order-1 allocations failures in TX path on its
wireless setup, that dont make any sense with MTU=1500 network, and non
SG capable hardware.
Turns out part of the problem comes from pskb_expand_head() not using
ksize() to get exact head size given by kmalloc(). Doing the same thing
than __alloc_skb() allows more tailroom in skb and can prevent future
reallocations.
As a bonus, struct skb_shared_info becomes cache line aligned.
Reported-by: Marc MERLIN <marc@merlins.org>
Tested-by: Marc MERLIN <marc@merlins.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As soon as an skb is queued into socket error queue, another thread
can consume it, so we are not allowed to reference skb anymore, or risk
use after free.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 3e4d3af501 (mm: stack based kmap_atomic()) we dont have
to disable BH anymore while mapping skb frags.
We can remove kmap_skb_frag() / kunmap_skb_frag() helpers and use
kmap_atomic() / kunmap_atomic()
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, most drivers do not support transmit SO_TIMESTAMPING. For those
that do support it, there is one appropriate response to the get_ts_info
query. This patch adds a common function providing this response.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit adds a new ethtool ioctl that exposes the SO_TIMESTAMPING
capabilities of a network interface. In addition, user space programs
can use this ioctl to discover the PTP Hardware Clock (PHC) device
associated with the interface.
Since software receive time stamps are handled by the stack, the generic
ethtool code can answer the query correctly in case the MAC or PHY
drivers lack special time stamping features.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add XOR instruction fo BPF machine. Needed for computing packet hashes.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Today, BPF filters are bind to sockets. Since BPF machine becomes handy
for other purposes, this patch allows to create unattached filter.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
