Tuning coalescing parameters on NIC can be really hard.
Servers can handle both bulk and RPC like traffic, with conflicting
goals : bulk flows want as big GRO packets as possible, RPC want minimal
latencies.
To reach big GRO packets on 10Gbe NIC, one can use :
ethtool -C eth0 rx-usecs 4 rx-frames 44
But this penalizes rpc sessions, with an increase of latencies, up to
50% in some cases, as NICs generally do not force an interrupt when
a packet with TCP Push flag is received.
Some NICs do not have an absolute timer, only a timer rearmed for every
incoming packet.
This patch uses a different strategy : Let GRO stack decides what do do,
based on traffic pattern.
Packets with Push flag wont be delayed.
Packets without Push flag might be held in GRO engine, if we keep
receiving data.
This new mechanism is off by default, and shall be enabled by setting
/sys/class/net/ethX/gro_flush_timeout to a value in nanosecond.
To fully enable this mechanism, drivers should use napi_complete_done()
instead of napi_complete().
Tested:
Ran 200 netperf TCP_STREAM from A to B (10Gbe mlx4 link, 8 RX queues)
Without this feature, we send back about 305,000 ACK per second.
GRO aggregation ratio is low (811/305 = 2.65 segments per GRO packet)
Setting a timer of 2000 nsec is enough to increase GRO packet sizes
and reduce number of ACK packets. (811/19.2 = 42)
Receiver performs less calls to upper stacks, less wakes up.
This also reduces cpu usage on the sender, as it receives less ACK
packets.
Note that reducing number of wakes up increases cpu efficiency, but can
decrease QPS, as applications wont have the chance to warmup cpu caches
doing a partial read of RPC requests/answers if they fit in one skb.
B:~# sar -n DEV 1 10 | grep eth0 | tail -1
Average: eth0 811269.80 305732.30 1199462.57 19705.72 0.00
0.00 0.50
B:~# echo 2000 >/sys/class/net/eth0/gro_flush_timeout
B:~# sar -n DEV 1 10 | grep eth0 | tail -1
Average: eth0 811577.30 19230.80 1199916.51 1239.80 0.00
0.00 0.50
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Babel uses rt_proto 42. Add to userspace visible header file.
Signed-off-by: Dave Taht <dave.taht@bufferbloat.net>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As NIC multicast filtering isn't perfect, and some platforms are
quite content to spew broadcasts, we should not trigger an event
for skb:kfree_skb when we do not have a match for such an incoming
datagram. We do though want to avoid sweeping the matter under the
rug entirely, so increment a suitable statistic.
This incorporates feedback from David L. Stevens, Karl Neiss and Eric
Dumazet.
V3 - use bool per David Miller
Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The entries in the Kbuild files are incorrectly sorted.
Matters for aesthetics only.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that both macvtap and tun are using skb_copy_datagram_iter, we
can kill the abomination that is skb_copy_datagram_const_iovec.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds skb_copy_datagram_iter, which is identical to
skb_copy_datagram_iovec except that it operates on iov_iter
instead of iovec.
Eventually all users of skb_copy_datagram_iovec should switch
over to iov_iter and then we can remove skb_copy_datagram_iovec.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pravin B Shelar says:
====================
Open vSwitch
First two patches are related to OVS MPLS support. Rest of patches
are mostly refactoring and minor improvements to openvswitch.
v1-v2:
- Fix conflicts due to "gue: Remote checksum offload"
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently we need the IP6_TNL_F_CAP_XMIT capabiltiy to transmit
packets through an ipv6 tunnel. This capability is set when the
tunnel gets configured, based on the tunnel endpoint addresses.
On tunnels with wildcard tunnel endpoints, we need to do the
capabiltiy checking on a per packet basis like it is done in
the receive path.
This patch extends ip6_tnl_xmit_ctl() to take local and remote
addresses as parameters to allow for per packet capabiltiy
checking.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Should be the same as other IPv6 address fields.
Current master produces sparse warnings without this change.
Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Allow datapath to recognize and extract MPLS labels into flow keys
and execute actions which push, pop, and set labels on packets.
Based heavily on work by Leo Alterman, Ravi K, Isaku Yamahata and Joe Stringer.
Cc: Ravi K <rkerur@gmail.com>
Cc: Leo Alterman <lalterman@nicira.com>
Cc: Isaku Yamahata <yamahata@valinux.co.jp>
Cc: Joe Stringer <joe@wand.net.nz>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Device can export MPLS GSO support in dev->mpls_features same way
it export vlan features in dev->vlan_features. So it is safe to
remove NETIF_F_GSO_MPLS redundant flag.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
By default the arch_fast_hash hashing function pointers are initialized
to jhash(2). If during boot-up a CPU with SSE4.2 is detected they get
updated to the CRC32 ones. This dispatching scheme incurs a function
pointer lookup and indirect call for every hashing operation.
rhashtable as a user of arch_fast_hash e.g. stores pointers to hashing
functions in its structure, too, causing two indirect branches per
hashing operation.
Using alternative_call we can get away with one of those indirect branches.
Acked-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
if_bridge.h uses struct in6_addr ip6, but wasn't including the in6.h
header. Thomas Backlund originally sent a patch to do this, but this
revealed a redefinition issue: https://lkml.org/lkml/2013/1/13/116
The redefinition issue should have been fixed by the following Linux
commits:
ee262ad827 inet: defines IPPROTO_* needed for module alias generation
cfd280c912 net: sync some IP headers with glibc
and the following glibc commit:
6c82a2f8d7c8e21e39237225c819f182ae438db3 Coordinate IPv6 definitions for Linux and glibc
so actually include the header now.
Reported-by: Colin Guthrie <colin@mageia.org>
Reported-by: Christiaan Welvaart <cjw@daneel.dyndns.org>
Reported-by: Thomas Backlund <tmb@mageia.org>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is only used in net/ipv6/inet6_hashtables.c.
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".
When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.
Having a helper like this means there will be less places to touch
during that transformation.
Based upon descriptions and patch from Al Viro.
Signed-off-by: David S. Miller <davem@davemloft.net>
Add if_tunnel flag TUNNEL_ENCAP_FLAG_REMCSUM to configure
remote checksum offload on an IP tunnel. Add logic in gue_build_header
to insert remote checksum offload option.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Define a private flag for remote checksun offload as well as a length
for the option.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a new GSO type, SKB_GSO_TUNNEL_REMCSUM, which indicates remote
checksum offload being done (in this case inner checksum must not
be offloaded to the NIC).
Added logic in __skb_udp_tunnel_segment to handle remote checksum
offload case.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add functions and basic definitions for processing standard flags,
private flags, and control messages. This includes definitions
to compute length of optional fields corresponding to a set of flags.
Flag validation is in validate_gue_flags function. This checks for
unknown flags, and that length of optional fields is <= length
in guehdr hlen.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move fou_build_header out of ip_tunnel.c and into fou.c splitting
it up into fou_build_header, gue_build_header, and fou_build_udp.
This allows for other users for TX of FOU or GUE. Change ip_tunnel_encap
to call fou_build_header or gue_build_header based on the tunnel
encapsulation type. Similarly, added fou_encap_hlen and gue_encap_hlen
functions which are called by ip_encap_hlen. New net/fou.h has
prototypes and defines for this.
Added NET_FOU_IP_TUNNELS configuration. When this is set, IP tunnels
can use FOU/GUE and fou module is also selected.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
File descriptors are always closed on exit :-)
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch allows to set ECN on a per-route basis in case the sysctl
tcp_ecn is not set to 1. In other words, when ECN is set for specific
routes, it provides a tcp_ecn=1 behaviour for that route while the rest
of the stack acts according to the global settings.
One can use 'ip route change dev $dev $net features ecn' to toggle this.
Having a more fine-grained per-route setting can be beneficial for various
reasons, for example, 1) within data centers, or 2) local ISPs may deploy
ECN support for their own video/streaming services [1], etc.
There was a recent measurement study/paper [2] which scanned the Alexa's
publicly available top million websites list from a vantage point in US,
Europe and Asia:
Half of the Alexa list will now happily use ECN (tcp_ecn=2, most likely
blamed to commit 255cac91c3 ("tcp: extend ECN sysctl to allow server-side
only ECN") ;)); the break in connectivity on-path was found is about
1 in 10,000 cases. Timeouts rather than receiving back RSTs were much
more common in the negotiation phase (and mostly seen in the Alexa
middle band, ranks around 50k-150k): from 12-thousand hosts on which
there _may_ be ECN-linked connection failures, only 79 failed with RST
when _not_ failing with RST when ECN is not requested.
It's unclear though, how much equipment in the wild actually marks CE
when buffers start to fill up.
We thought about a fallback to non-ECN for retransmitted SYNs as another
global option (which could perhaps one day be made default), but as Eric
points out, there's much more work needed to detect broken middleboxes.
Two examples Eric mentioned are buggy firewalls that accept only a single
SYN per flow, and middleboxes that successfully let an ECN flow establish,
but later mark CE for all packets (so cwnd converges to 1).
[1] http://www.ietf.org/proceedings/89/slides/slides-89-tsvarea-1.pdf, p.15
[2] http://ecn.ethz.ch/
Joint work with Daniel Borkmann.
Reference: http://thread.gmane.org/gmane.linux.network/335797
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function cookie_check_timestamp(), both called from IPv4/6 context,
is being used to decode the echoed timestamp from the SYN/ACK into TCP
options used for follow-up communication with the peer.
We can remove ECN handling from that function, split it into a separate
one, and simply rename the original function into cookie_decode_options().
cookie_decode_options() just fills in tcp_option struct based on the
echoed timestamp received from the peer. Anything that fails in this
function will actually discard the request socket.
While this is the natural place for decoding options such as ECN which
commit 172d69e63c ("syncookies: add support for ECN") added, we argue
that in particular for ECN handling, it can be checked at a later point
in time as the request sock would actually not need to be dropped from
this, but just ECN support turned off.
Therefore, we split this functionality into cookie_ecn_ok(), which tells
us if the timestamp indicates ECN support AND the tcp_ecn sysctl is enabled.
This prepares for per-route ECN support: just looking at the tcp_ecn sysctl
won't be enough anymore at that point; if the timestamp indicates ECN
and sysctl tcp_ecn == 0, we will also need to check the ECN dst metric.
This would mean adding a route lookup to cookie_check_timestamp(), which
we definitely want to avoid. As we already do a route lookup at a later
point in cookie_{v4,v6}_check(), we can simply make use of that as well
for the new cookie_ecn_ok() function w/o any additional cost.
Joint work with Daniel Borkmann.
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Yaogong replaces TCP out of order receive queue by an RB tree.
As netem already does a private skb->{next/prev/tstamp} union
with a 'struct rb_node', lets do this in a cleaner way.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yaogong Wang <wygivan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The makefile for sanitizing kernel headers uses the kbuild file
to determine which files to do. Several networking related headers
were missing. Without these headers iproute2 build would break.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add code to issue CONFIG_DEV "get" firmware command.
This command is used in order to obtain certain parameters used for
supporting various RX checksumming options and vxlan UDP port.
The GET operation is allowed for VFs too.
Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Shani Michaeli <shanim@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
flow_limit in struct softnet_data is only read from local cpu
and can be moved to fill a hole, reducing softnet_data size by
64 bytes on x86_64
While we are at it, move output_queue, output_queue_tailp and
completion_queue, so that rx / tx paths touch a single cache line.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
"A bit has accumulated, but it's been a week or so since my last batch
of post-merge-window fixes, so...
1) Missing module license in netfilter reject module, from Pablo.
Lots of people ran into this.
2) Off by one in mac80211 baserate calculation, from Karl Beldan.
3) Fix incorrect return value from ax88179_178a driver's set_mac_addr
op, which broke use of it with bonding. From Ian Morgan.
4) Checking of skb_gso_segment()'s return value was not all
encompassing, it can return an SKB pointer, a pointer error, or
NULL. Fix from Florian Westphal.
This is crummy, and longer term will be fixed to just return error
pointers or a real SKB.
6) Encapsulation offloads not being handled by
skb_gso_transport_seglen(). From Florian Westphal.
7) Fix deadlock in TIPC stack, from Ying Xue.
8) Fix performance regression from using rhashtable for netlink
sockets. The problem was the synchronize_net() invoked for every
socket destroy. From Thomas Graf.
9) Fix bug in eBPF verifier, and remove the strong dependency of BPF
on NET. From Alexei Starovoitov.
10) In qdisc_create(), use the correct interface to allocate
->cpu_bstats, otherwise the u64_stats_sync member isn't
initialized properly. From Sabrina Dubroca.
11) Off by one in ip_set_nfnl_get_byindex(), from Dan Carpenter.
12) nf_tables_newchain() was erroneously expecting error pointers from
netdev_alloc_pcpu_stats(). It only returna a valid pointer or
NULL. From Sabrina Dubroca.
13) Fix use-after-free in _decode_session6(), from Li RongQing.
14) When we set the TX flow hash on a socket, we mistakenly do so
before we've nailed down the final source port. Move the setting
deeper to fix this. From Sathya Perla.
15) NAPI budget accounting in amd-xgbe driver was counting descriptors
instead of full packets, fix from Thomas Lendacky.
16) Fix total_data_buflen calculation in hyperv driver, from Haiyang
Zhang.
17) Fix bcma driver build with OF_ADDRESS disabled, from Hauke
Mehrtens.
18) Fix mis-use of per-cpu memory in TCP md5 code. The problem is
that something that ends up being vmalloc memory can't be passed
to the crypto hash routines via scatter-gather lists. From Eric
Dumazet.
19) Fix regression in promiscuous mode enabling in cdc-ether, from
Olivier Blin.
20) Bucket eviction and frag entry killing can race with eachother,
causing an unlink of the object from the wrong list. Fix from
Nikolay Aleksandrov.
21) Missing initialization of spinlock in cxgb4 driver, from Anish
Bhatt.
22) Do not cache ipv4 routing failures, otherwise if the sysctl for
forwarding is subsequently enabled this won't be seen. From
Nicolas Cavallari"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (131 commits)
drivers: net: cpsw: Support ALLMULTI and fix IFF_PROMISC in switch mode
drivers: net: cpsw: Fix broken loop condition in switch mode
net: ethtool: Return -EOPNOTSUPP if user space tries to read EEPROM with lengh 0
stmmac: pci: set default of the filter bins
net: smc91x: Fix gpios for device tree based booting
mpls: Allow mpls_gso to be built as module
mpls: Fix mpls_gso handler.
r8152: stop submitting intr for -EPROTO
netfilter: nft_reject_bridge: restrict reject to prerouting and input
netfilter: nft_reject_bridge: don't use IP stack to reject traffic
netfilter: nf_reject_ipv6: split nf_send_reset6() in smaller functions
netfilter: nf_reject_ipv4: split nf_send_reset() in smaller functions
netfilter: nf_tables_bridge: update hook_mask to allow {pre,post}routing
drivers/net: macvtap and tun depend on INET
drivers/net, ipv6: Select IPv6 fragment idents for virtio UFO packets
drivers/net: Disable UFO through virtio
net: skb_fclone_busy() needs to detect orphaned skb
gre: Use inner mac length when computing tunnel length
mlx4: Avoid leaking steering rules on flow creation error flow
net/mlx4_en: Don't attempt to TX offload the outer UDP checksum for VXLAN
...
Pull scheduler fixes from Ingo Molnar:
"Various scheduler fixes all over the place: three SCHED_DL fixes,
three sched/numa fixes, two generic race fixes and a comment fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/dl: Fix preemption checks
sched: Update comments for CLONE_NEWNS
sched: stop the unbound recursion in preempt_schedule_context()
sched/fair: Fix division by zero sysctl_numa_balancing_scan_size
sched/fair: Care divide error in update_task_scan_period()
sched/numa: Fix unsafe get_task_struct() in task_numa_assign()
sched/deadline: Fix races between rt_mutex_setprio() and dl_task_timer()
sched/deadline: Don't replenish from a !SCHED_DEADLINE entity
sched: Fix race between task_group and sched_task_group
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, plus on the kernel side:
- a revert for a newly introduced PMU driver which isn't complete yet
and where we ran out of time with fixes (to be tried again in
v3.19) - this makes up for a large chunk of the diffstat.
- compilation warning fixes
- a printk message fix
- event_idx usage fixes/cleanups"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf probe: Trivial typo fix for --demangle
perf tools: Fix report -F dso_from for data without branch info
perf tools: Fix report -F dso_to for data without branch info
perf tools: Fix report -F symbol_from for data without branch info
perf tools: Fix report -F symbol_to for data without branch info
perf tools: Fix report -F mispredict for data without branch info
perf tools: Fix report -F in_tx for data without branch info
perf tools: Fix report -F abort for data without branch info
perf tools: Make CPUINFO_PROC an array to support different kernel versions
perf callchain: Use global caching provided by libunwind
perf/x86/intel: Revert incomplete and undocumented Broadwell client support
perf/x86: Fix compile warnings for intel_uncore
perf: Fix typos in sample code in the perf_event.h header
perf: Fix and clean up initialization of pmu::event_idx
perf: Fix bogus kernel printk
perf diff: Add missing hists__init() call at tool start
Pull core fixes from Ingo Molnar:
"The tree contains two RCU fixes and a compiler quirk comment fix"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcu: Make rcu_barrier() understand about missing rcuo kthreads
compiler/gcc4+: Remove inaccurate comment about 'asm goto' miscompiles
rcu: More on deadlock between CPU hotplug and expedited grace periods
Pablo Neira Ayuso says:
====================
netfilter/ipvs fixes for net
The following patchset contains fixes for netfilter/ipvs. This round of
fixes is larger than usual at this stage, specifically because of the
nf_tables bridge reject fixes that I would like to see in 3.18. The
patches are:
1) Fix a null-pointer dereference that may occur when logging
errors. This problem was introduced by 4a4739d56b ("ipvs: Pull
out crosses_local_route_boundary logic") in v3.17-rc5.
2) Update hook mask in nft_reject_bridge so we can also filter out
packets from there. This fixes 36d2af5 ("netfilter: nf_tables: allow
to filter from prerouting and postrouting"), which needs this chunk
to work.
3) Two patches to refactor common code to forge the IPv4 and IPv6
reject packets from the bridge. These are required by the nf_tables
reject bridge fix.
4) Fix nft_reject_bridge by avoiding the use of the IP stack to reject
packets from the bridge. The idea is to forge the reject packets and
inject them to the original port via br_deliver() which is now
exported for that purpose.
5) Restrict nft_reject_bridge to bridge prerouting and input hooks.
the original skbuff may cloned after prerouting when the bridge stack
needs to flood it to several bridge ports, it is too late to reject
the traffic.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
That can be reused by the reject bridge expression to build the reject
packet. The new functions are:
* nf_reject_ip6_tcphdr_get(): to sanitize and to obtain the TCP header.
* nf_reject_ip6hdr_put(): to build the IPv6 header.
* nf_reject_ip6_tcphdr_put(): to build the TCP header.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
That can be reused by the reject bridge expression to build the reject
packet. The new functions are:
* nf_reject_ip_tcphdr_get(): to sanitize and to obtain the TCP header.
* nf_reject_iphdr_put(): to build the IPv4 header.
* nf_reject_ip_tcphdr_put(): to build the TCP header.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
UFO is now disabled on all drivers that work with virtio net headers,
but userland may try to send UFO/IPv6 packets anyway. Instead of
sending with ID=0, we should select identifiers on their behalf (as we
used to).
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Fixes: 916e4cf46d ("ipv6: reuse ip6_frag_id from ip6_ufo_append_data")
Signed-off-by: David S. Miller <davem@davemloft.net>
Some drivers are unable to perform TX completions in a bound time.
They instead call skb_orphan()
Problem is skb_fclone_busy() has to detect this case, otherwise
we block TCP retransmits and can freeze unlucky tcp sessions on
mostly idle hosts.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Fixes: 1f3279ae0c ("tcp: avoid retransmits of TCP packets hanging in host queues")
Signed-off-by: David S. Miller <davem@davemloft.net>
Add support for reading switch registers with 'ethtool -d'.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
On some chips it is possible to access the switch eeprom.
Add infrastructure support for it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some switches provide chip temperature data.
Add support for reporting it through the hwmon subsystem.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull two RCU fixes from Paul E. McKenney:
" - Complete the work of commit dd56af42bd (rcu: Eliminate deadlock
between CPU hotplug and expedited grace periods), which was
intended to allow synchronize_sched_expedited() to be safely
used when holding locks acquired by CPU-hotplug notifiers.
This commit makes the put_online_cpus() avoid the deadlock
instead of just handling the get_online_cpus().
- Complete the work of commit 35ce7f29a4 (rcu: Create rcuo
kthreads only for onlined CPUs), which was intended to allow
RCU to avoid allocating unneeded kthreads on systems where the
firmware says that there are more CPUs than are really present.
This commit makes rcu_barrier() aware of the mismatch, so that
it doesn't hang waiting for non-existent CPUs. "
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge misc fixes from Andrew Morton:
"21 fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (21 commits)
mm/balloon_compaction: fix deflation when compaction is disabled
sh: fix sh770x SCIF memory regions
zram: avoid NULL pointer access in concurrent situation
mm/slab_common: don't check for duplicate cache names
ocfs2: fix d_splice_alias() return code checking
mm: rmap: split out page_remove_file_rmap()
mm: memcontrol: fix missed end-writeback page accounting
mm: page-writeback: inline account_page_dirtied() into single caller
lib/bitmap.c: fix undefined shift in __bitmap_shift_{left|right}()
drivers/rtc/rtc-bq32k.c: fix register value
memory-hotplug: clear pgdat which is allocated by bootmem in try_offline_node()
drivers/rtc/rtc-s3c.c: fix initialization failure without rtc source clock
kernel/kmod: fix use-after-free of the sub_info structure
drivers/rtc/rtc-pm8xxx.c: rework to support pm8941 rtc
mm, thp: fix collapsing of hugepages on madvise
drivers: of: add return value to of_reserved_mem_device_init()
mm: free compound page with correct order
gcov: add ARM64 to GCOV_PROFILE_ALL
fsnotify: next_i is freed during fsnotify_unmount_inodes.
mm/compaction.c: avoid premature range skip in isolate_migratepages_range
...
Commit 0a31bc97c8 ("mm: memcontrol: rewrite uncharge API") changed
page migration to uncharge the old page right away. The page is locked,
unmapped, truncated, and off the LRU, but it could race with writeback
ending, which then doesn't unaccount the page properly:
test_clear_page_writeback() migration
wait_on_page_writeback()
TestClearPageWriteback()
mem_cgroup_migrate()
clear PCG_USED
mem_cgroup_update_page_stat()
if (PageCgroupUsed(pc))
decrease memcg pages under writeback
release pc->mem_cgroup->move_lock
The per-page statistics interface is heavily optimized to avoid a
function call and a lookup_page_cgroup() in the file unmap fast path,
which means it doesn't verify whether a page is still charged before
clearing PageWriteback() and it has to do it in the stat update later.
Rework it so that it looks up the page's memcg once at the beginning of
the transaction and then uses it throughout. The charge will be
verified before clearing PageWriteback() and migration can't uncharge
the page as long as that is still set. The RCU lock will protect the
memcg past uncharge.
As far as losing the optimization goes, the following test results are
from a microbenchmark that maps, faults, and unmaps a 4GB sparse file
three times in a nested fashion, so that there are two negative passes
that don't account but still go through the new transaction overhead.
There is no actual difference:
old: 33.195102545 seconds time elapsed ( +- 0.01% )
new: 33.199231369 seconds time elapsed ( +- 0.03% )
The time spent in page_remove_rmap()'s callees still adds up to the
same, but the time spent in the function itself seems reduced:
# Children Self Command Shared Object Symbol
old: 0.12% 0.11% filemapstress [kernel.kallsyms] [k] page_remove_rmap
new: 0.12% 0.08% filemapstress [kernel.kallsyms] [k] page_remove_rmap
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: <stable@vger.kernel.org> [3.17.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A follow-up patch would have changed the call signature. To save the
trouble, just fold it instead.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Vladimir Davydov <vdavydov@parallels.com>
Cc: <stable@vger.kernel.org> [3.17.x]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If an anonymous mapping is not allowed to fault thp memory and then
madvise(MADV_HUGEPAGE) is used after fault, khugepaged will never
collapse this memory into thp memory.
This occurs because the madvise(2) handler for thp, hugepage_madvise(),
clears VM_NOHUGEPAGE on the stack and it isn't stored in vma->vm_flags
until the final action of madvise_behavior(). This causes the
khugepaged_enter_vma_merge() to be a no-op in hugepage_madvise() when
the vma had previously had VM_NOHUGEPAGE set.
Fix this by passing the correct vma flags to the khugepaged mm slot
handler. There's no chance khugepaged can run on this vma until after
madvise_behavior() returns since we hold mm->mmap_sem.
It would be possible to clear VM_NOHUGEPAGE directly from vma->vm_flags
in hugepage_advise(), but I didn't want to introduce special case
behavior into madvise_behavior(). I think it's best to just let it
always set vma->vm_flags itself.
Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Suleiman Souhlal <suleiman@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Driver calling of_reserved_mem_device_init() might be interested if the
initialization has been successful or not, so add support for returning
error code.
This fixes a build warining caused by commit 7bfa5ab6fa ("drivers:
dma-coherent: add initialization from device tree"), which has been
merged without this change and without fixing function return value.
Fixes: 7bfa5ab6fa ("drivers: dma-coherent: add initialization from device tree")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: Michal Nazarewicz <mina86@mina86.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Josh Cartwright <joshc@codeaurora.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In neigh_parms_release() we loop over all entries to find the entry given in
argument and being able to remove it from the list. By using a double linked
list, we can avoid this loop.
Here are some numbers with 30 000 dummy interfaces configured:
Before the patch:
$ time rmmod dummy
real 2m0.118s
user 0m0.000s
sys 1m50.048s
After the patch:
$ time rmmod dummy
real 1m9.970s
user 0m0.000s
sys 0m47.976s
Suggested-by: Thierry Herbelot <thierry.herbelot@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet