The GMA500 GPU driver uses GEM shmem objects, but with a new twist: the
backing RAM has to be below 4GB. Not a problem while the boards
supported only 4GB: but now Intel's D2700MUD boards support 8GB, and
their GMA3600 is managed by the GMA500 driver.
shmem/tmpfs has never pretended to support hardware restrictions on the
backing memory, but it might have appeared to do so before v3.1, and
even now it works fine until a page is swapped out then back in. When
read_cache_page_gfp() supplied a freshly allocated page for copy, that
compensated for whatever choice might have been made by earlier swapin
readahead; but swapoff was likely to destroy the illusion.
We'd like to continue to support GMA500, so now add a new
shmem_should_replace_page() check on the zone when about to move a page
from swapcache to filecache (in swapin and swapoff cases), with
shmem_replace_page() to allocate and substitute a suitable page (given
gma500/gem.c's mapping_set_gfp_mask GFP_KERNEL | __GFP_DMA32).
This does involve a minor extension to mem_cgroup_replace_page_cache()
(the page may or may not have already been charged); and I've removed a
comment and call to mem_cgroup_uncharge_cache_page(), which in fact is
always a no-op while PageSwapCache.
Also removed optimization of an unlikely path in shmem_getpage_gfp(),
now that we need to check PageSwapCache more carefully (a racing caller
might already have made the copy). And at one point shmem_unuse_inode()
needs to use the hitherto private page_swapcount(), to guard against
racing with inode eviction.
It would make sense to extend shmem_should_replace_page(), to cover
cpuset and NUMA mempolicy restrictions too, but set that aside for now:
needs a cleanup of shmem mempolicy handling, and more testing, and ought
to handle swap faults in do_swap_page() as well as shmem.
Change-Id: I45bd35a42eab75c8ad1db7a7ae30b924718b2b67
Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Christoph Hellwig <hch@infradead.org>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Stephane Marchesin <marcheu@chromium.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Dave Airlie <airlied@gmail.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Rob Clark <rob.clark@linaro.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Sematically speaking, xfrm_mgr.acquire is called when kernel intends to ask
user space IKE daemon to negotiate SAs with peers. IOW the direction will
*always* be XFRM_POLICY_OUT, so remove int dir for clarity.
Change-Id: Id4df779e818c5b6f5eccb9bf8250c17eb729f101
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After SA is setup, one timer is armed to detect soft/hard expiration,
however the timer handler uses xtime to do the math. This makes hard
expiration occurs first before soft expiration after setting new date
with big interval. As a result new child SA is deleted before rekeying
the new one.
Signed-off-by: Fan Du <fdu@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I44623eedcfb44088e86845b4726198a5cca02c80
xfrm_selector_match
xfrm_sec_ctx_match
__xfrm4_selector_match
__xfrm6_selector_match
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I0cb9bc9e9f5689edc4ee73b6a9d838a89ea5a5de
In some cases after deleting a policy from the SPD the policy would
remain in the dst/flow/route cache for an extended period of time
which caused problems for SELinux as its dynamic network access
controls key off of the number of XFRM policy and state entries.
This patch corrects this problem by forcing a XFRM garbage collection
whenever a policy is sucessfully removed.
Reported-by: Ondrej Moris <omoris@redhat.com>
Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I1aae89f15a467a7661caec89edfef21aa639b852
The error exit path needs err explicitly set. Otherwise it
returns success and the only caller, xfrm_output_resume(),
would oops in skb_dst(skb)->ops derefence as skb_dst(skb) is
NULL.
Bug introduced in commit bb65a9cb (xfrm: removes a superfluous
check and add a statistic).
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Cc: Li RongQing <roy.qing.li@gmail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I67e8f934400c9dcb8533ab778dc2555267540109
Commit 0017c0b "xfrm: Fix replay notification for esn." is off by one
for the sequence number wrapped case as UINT_MAX is 0xffffffff, not
0x100000000. ;)
Just calculate the diff like done everywhere else in the file.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I56b84e105364ce7102a243413c41f2491e6528bd
We may miscalculate the sequence number difference from the
last time we send a notification if a sequence number wrap
occured in the meantime. We fix this by adding a separate
replay notify function for esn. Here we take the high bits
of the sequence number into account to calculate the
difference.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I479b8e5a402828d226b8bac67d07fb489f169fa4
because xfrm policy direction has same value with corresponding
flow direction, so this problem is covered.
In xfrm_lookup and __xfrm_policy_check, flow_cache_lookup is used to
accelerate the lookup.
Flow direction is given to flow_cache_lookup by policy_to_flow_dir.
When the flow cache is mismatched, callback 'resolver' is called.
'resolver' requires xfrm direction,
so convert direction back to xfrm direction.
Signed-off-by: Baker Zhang <baker.zhang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Ie626dedd5affcb1f480e37b071c546e25ff0d83d
There is no need to modify the netlink dispatch table at runtime.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: If33577532b9970f8c07b8e577275ddb6aa48cc20
By default, DSCP is copying during encapsulation.
Copying the DSCP in IPsec tunneling may be a bit dangerous because packets with
different DSCP may get reordered relative to each other in the network and then
dropped by the remote IPsec GW if the reordering becomes too big compared to the
replay window.
It is possible to avoid this copy with netfilter rules, but it's very convenient
to be able to configure it for each SA directly.
This patch adds a toogle for this purpose. By default, it's not set to maintain
backward compatibility.
Field flags in struct xfrm_usersa_info is full, hence I add a new attribute.
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I885117f02790536e2c5002232b3b33be651a568d
We currently can not insert policies with mark and mask
such that some flows would be matched from both policies.
We make this possible when the priority of these policies
are different. If both policies match a flow, the one with
the higher priority is used.
Reported-by: Emmanuel Thierry <emmanuel.thierry@telecom-bretagne.eu>
Reported-by: Romain Kuntz <r.kuntz@ipflavors.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: Ib9d456b956784fbee982ed9191f22f9ed097cd47
As the default, we blackhole packets until the key manager resolves
the states. This patch implements a packet queue where IPsec packets
are queued until the states are resolved. We generate a dummy xfrm
bundle, the output routine of the returned route enqueues the packet
to a per policy queue and arms a timer that checks for state resolution
when dst_output() is called. Once the states are resolved, the packets
are sent out of the queue. If the states are not resolved after some
time, the queue is flushed.
This patch keeps the defaut behaviour to blackhole packets as long
as we have no states. To enable the packet queue the sysctl
xfrm_larval_drop must be switched off.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I5ff2ae58ba580505914683e3571ee96974ee4966
Add a big comment explaining how the field works, and use defines
instead of magic constants for the values assigned to it.
Suggested by Joe Perches.
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I2c8ca84d38cd49ccc1207db588108d78e6f9403a
Mark existing algorithms as pfkey supported and make pfkey only use algorithms
that have pfkey_supported set.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I8a51662015715f6444011ce2298fe7d8c9651a81
All users of xfrm_addr_cmp() use its result as boolean.
Introduce xfrm_addr_equal() (which is equal to !xfrm_addr_cmp())
and convert all users.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I992ceb67c76beea2332c494d92f4f3571a31f0c2
Missing multiplication of block size by sizeof(struct hlist_head)
can cause xfrm_hash_free() to be called with wrong second argument
so that kfree() is called on a block allocated with vzalloc() or
__get_free_pages() or free_pages() is called with wrong order when
a namespace with enough policies is removed.
Bug introduced by commit a35f6c5d, i.e. versions >= 2.6.29 are
affected.
Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I3e431a20bebf2bb1beeb450b9e07f30bfd263f1f
All of the xfrm_replay->advance functions in xfrm_replay.c check if
x->replay_esn->replay_window is zero (and return if so). However,
one of them, xfrm_replay_advance_bmp(), divides by that value (in the
'%' operator) before doing the check, which can potentially trigger
a divide-by-zero exception. Some compilers will also assume that the
earlier division means the value cannot be zero later, and thus will
eliminate the subsequent zero check as dead code.
This patch moves the division to after the check.
Signed-off-by: Nickolai Zeldovich <nickolai@csail.mit.edu>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I0a8ed8f8a3ccc89e3081c5c94ac67a0c70670529
afinfo->type_map and afinfo->mode_map deserve separated locks,
they are different things.
We should just take RCU read lock to protect afinfo itself,
but not for the inner pointers.
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: Ifaa8fbd443616d2a6b46efc09d6f17a5dc9906c1
Similar to commit 418a99ac6a
(Replace rwlock on xfrm_policy_afinfo with rcu), the rwlock
on xfrm_state_afinfo can be replaced by RCU too.
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I4cbf6c7a1f51d04651032df3de271f953d913190
IPSEC uses block ciphers asynchronous, but probes only for synchronous block
ciphers and makes ealg entries only available if synchronous block cipher is
found. So with setup, where hardware crypto driver registers asynchronous
block ciphers and software crypto module is not build, ealg is not marked
as being available.
Use crypto_has_ablkcipher instead and remove ASYNC mask.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: I54c7eacc0b466ac1531d203d188a8cc9d83d2358
Remove the check if x->km.state equal to XFRM_STATE_VALID in
xfrm_state_check_expire(), which will be done before call
xfrm_state_check_expire().
add a LINUX_MIB_XFRMOUTSTATEINVALID statistic to record the
outbound error due to invalid xfrm state.
Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: Iadce369611e5596daeac8b030ac316b7da8ca8d6
x->replay_esn is already checked in if clause,
so remove check and ident properly
Signed-off-by: Ulrich Weber <ulrich.weber@sophos.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Change-Id: Ie49d59a73961651cb804085007919c834315f174
Instead of using a fixed value of "-1" or "-EMSGSIZE", propagate what
the nla_*() interfaces actually return.
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I1e2b27cf758949e85967fbdd30266e19fdbbc14b
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I8d10940220e85d715753d409f55dbf74e553a4c2
These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I902e64bada32556cac1091cccc77fe3b076ff056
[ Upstream commit c04e32e911653442fc834be6e92e072aeebe01a1 ]
At least for ARM64 kernels compiled with the crosstoolchain from
Debian/stretch or with the toolchain from kernel.org the line number is
not decoded correctly by 'decode_stacktrace.sh':
$ echo "[ 136.513051] f1+0x0/0xc [kcrash]" | \
CROSS_COMPILE=/opt/gcc-8.1.0-nolibc/aarch64-linux/bin/aarch64-linux- \
./scripts/decode_stacktrace.sh /scratch/linux-arm64/vmlinux \
/scratch/linux-arm64 \
/nfs/debian/lib/modules/4.20.0-devel
[ 136.513051] f1 (/linux/drivers/staging/kcrash/kcrash.c:68) kcrash
If addr2line from the toolchain is used the decoded line number is correct:
[ 136.513051] f1 (/linux/drivers/staging/kcrash/kcrash.c:57) kcrash
Link: http://lkml.kernel.org/r/20190527083425.3763-1-manut@linutronix.de
Signed-off-by: Manuel Traut <manut@linutronix.de>
Acked-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I71d5204ee59336f4091601e726a5930b7bdf0662
[ Upstream commit 67a28de47faa83585dd644bd4c31e5a1d9346c50 ]
Running something like:
decodecode vmlinux .
leads to interested results where not only the leading "." gets stripped
from the displayed paths, but also anywhere in the string, displaying
something like:
kvm_vcpu_check_block (arch/arm64/kvm/virt/kvm/kvm_mainc:2141)
which doesn't help further processing.
Fix it by only stripping the base path if it is a prefix of the path.
Link: http://lkml.kernel.org/r/20181210174659.31054-3-marc.zyngier@arm.com
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Change-Id: I3cb23106d284450f441e7ffb352cd7d05ec1dee4
Kirill reported that the decode_stacktrace.sh script was broken by the
following commit:
bb5e5ce545f2 ("x86/dumpstack: Remove kernel text addresses from stack dump")
Fix it by updating the per-line absolute address check to also check for
function-based address lines like the following:
write_sysrq_trigger+0x51/0x60
I didn't remove the check for absolute addresses because it's still
needed for ARM.
Reported-by: Kirill A. Shutemov <kirill@shutemov.name>
Tested-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <alexander.levin@verizon.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: bb5e5ce545f2 ("x86/dumpstack: Remove kernel text addresses from stack dump")
Link: http://lkml.kernel.org/r/20161128230635.4n2ofgawltgexgcg@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Change-Id: Ic716321f593f8ae5766c7248352b27ddc792e438
scripts/decode_stacktrace.sh presently displays module symbols as
func+0x0ff/0x5153 [module]
Add a third argument: the pathname of a directory where the script
should look for the file module.ko so that the output appears as
func (foo/bar.c:123) module
Without the argument or if the module file isn't found the script prints
such symbols as is without decoding.
Signed-off-by: Konstantin Khlebnikov <koct9i@gmail.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: I73a3cafcb3846c7a08bc75972f188d116fb55edf
Fix the stack decoder for the ARM architecture.
An ARM stack is designed as :
[ 81.547704] [<c023eb04>] (bucket_find_contain) from [<c023ec88>] (check_sync+0x40/0x4f8)
[ 81.559668] [<c023ec88>] (check_sync) from [<c023f8c4>] (debug_dma_sync_sg_for_cpu+0x128/0x194)
[ 81.571583] [<c023f8c4>] (debug_dma_sync_sg_for_cpu) from [<c0327dec>] (__videobuf_s
The current script doesn't expect the symbols to be bound by
parenthesis, and triggers the following errors :
awk: cmd. line:1: error: Unmatched ( or \(: / (check_sync$/
[ 81.547704] (bucket_find_contain) from (check_sync+0x40/0x4f8)
Fix it by chopping starting and ending parenthesis from the each symbol
name.
As a side note, this probably comes from the function
dump_backtrace_entry(), which is implemented differently for each
architecture. That makes a single decoding script a bit a challenge.
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Michal Marek <mmarek@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: Id056e494eb41a5c8740d9ce39dd959bca9590bfb
Right now when people try to report issues in the kernel they send stack
dumps to eachother, which looks something like this:
[ 6.906437] [<ffffffff811f0e90>] ? backtrace_test_irq_callback+0x20/0x20
[ 6.907121] [<ffffffff84388ce8>] dump_stack+0x52/0x7f
[ 6.907640] [<ffffffff811f0ec8>] backtrace_regression_test+0x38/0x110
[ 6.908281] [<ffffffff813596a0>] ? proc_create_data+0xa0/0xd0
[ 6.908870] [<ffffffff870a8040>] ? proc_modules_init+0x22/0x22
[ 6.909480] [<ffffffff810020c2>] do_one_initcall+0xc2/0x1e0
[...]
However, most of the text you get is pure garbage.
The only useful thing above is the function name. Due to the amount of
different kernel code versions and various configurations being used,
the kernel address and the offset into the function are not really
helpful in determining where the problem actually occured.
Too often the result of someone looking at a stack dump is asking the
person who sent it for a translation for one or more 'addr2line'
translations. Which slows down the entire process of debugging the
issue (and really annoying).
The decode_stacktrace script is an attempt to make the output more
useful and easy to work with by translating all kernel addresses in the
stack dump into line numbers. Which means that the stack dump would
look like this:
[ 635.148361] dump_stack (lib/dump_stack.c:52)
[ 635.149127] warn_slowpath_common (kernel/panic.c:418)
[ 635.150214] warn_slowpath_null (kernel/panic.c:453)
[ 635.151031] _oalloc_pages_slowpath+0x6a/0x7d0
[ 635.152171] ? zone_watermark_ok (mm/page_alloc.c:1728)
[ 635.152988] ? get_page_from_freelist (mm/page_alloc.c:1939)
[ 635.154766] __alloc_pages_nodemask (mm/page_alloc.c:2766)
It's pretty obvious why this is better than the previous stack dump
before.
Usage is pretty simple:
./decode_stacktrace.sh [vmlinux] [base path]
Where vmlinux is the vmlinux to extract line numbers from and base path
is the path that points to the root of the build tree, for example:
./decode_stacktrace.sh vmlinux /home/sasha/linux/ < input.log > output.log
The stack trace should be piped through it (I, for example, just pipe
the output of the serial console of my KVM test box through it).
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Change-Id: Ibd1b079d54d49b081a72f44136c3b6c478523fbb
[ Upstream commit 0d08c42cf9 ]
commit 6ff50cd555 ("tcp: gso: do not generate out of order packets")
had an heuristic that can trigger a warning in skb_try_coalesce(),
because skb->truesize of the gso segments were exactly set to mss.
This breaks the requirement that
skb->truesize >= skb->len + truesizeof(struct sk_buff);
It can trivially be reproduced by :
ifconfig lo mtu 1500
ethtool -K lo tso off
netperf
As the skbs are looped into the TCP networking stack, skb_try_coalesce()
warns us of these skb under-estimating their truesize.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: Iced7cd04a2860fcc14815c4f5564e01840ac41e3
[ Upstream commit 98e09386c0 ]
After commit c9eeec26e3 ("tcp: TSQ can use a dynamic limit"), several
users reported throughput regressions, notably on mvneta and wifi
adapters.
802.11 AMPDU requires a fair amount of queueing to be effective.
This patch partially reverts the change done in tcp_write_xmit()
so that the minimal amount is sysctl_tcp_limit_output_bytes.
It also remove the use of this sysctl while building skb stored
in write queue, as TSO autosizing does the right thing anyway.
Users with well behaving NICS and correct qdisc (like sch_fq),
can then lower the default sysctl_tcp_limit_output_bytes value from
128KB to 8KB.
This new usage of sysctl_tcp_limit_output_bytes permits each driver
authors to check how their driver performs when/if the value is set
to a minimum of 4KB.
Normally, line rate for a single TCP flow should be possible,
but some drivers rely on timers to perform TX completion and
too long TX completion delays prevent reaching full throughput.
Fixes: c9eeec26e3 ("tcp: TSQ can use a dynamic limit")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Sujith Manoharan <sujith@msujith.org>
Reported-by: Arnaud Ebalard <arno@natisbad.org>
Tested-by: Sujith Manoharan <sujith@msujith.org>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I1fab5c795148dff3da34b42c7808476f51d99f89
[ Upstream commit c9eeec26e3 ]
When TCP Small Queues was added, we used a sysctl to limit amount of
packets queues on Qdisc/device queues for a given TCP flow.
Problem is this limit is either too big for low rates, or too small
for high rates.
Now TCP stack has rate estimation in sk->sk_pacing_rate, and TSO
auto sizing, it can better control number of packets in Qdisc/device
queues.
New limit is two packets or at least 1 to 2 ms worth of packets.
Low rates flows benefit from this patch by having even smaller
number of packets in queues, allowing for faster recovery,
better RTT estimations.
High rates flows benefit from this patch by allowing more than 2 packets
in flight as we had reports this was a limiting factor to reach line
rate. [ In particular if TX completion is delayed because of coalescing
parameters ]
Example for a single flow on 10Gbp link controlled by FQ/pacing
14 packets in flight instead of 2
$ tc -s -d qd
qdisc fq 8001: dev eth0 root refcnt 32 limit 10000p flow_limit 100p
buckets 1024 quantum 3028 initial_quantum 15140
Sent 1168459366606 bytes 771822841 pkt (dropped 0, overlimits 0
requeues 6822476)
rate 9346Mbit 771713pps backlog 953820b 14p requeues 6822476
2047 flow, 2046 inactive, 1 throttled, delay 15673 ns
2372 gc, 0 highprio, 0 retrans, 9739249 throttled, 0 flows_plimit
Note that sk_pacing_rate is currently set to twice the actual rate, but
this might be refined in the future when a flow is in congestion
avoidance.
Additional change : skb->destructor should be set to tcp_wfree().
A future patch (for linux 3.13+) might remove tcp_limit_output_bytes
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Wei Liu <wei.liu2@citrix.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change-Id: I481dfb7b15ae4fc699e03e2ef846b0631c5ebb3f
GSO TCP handler has following issues :
1) ooo_okay from original GSO packet is duplicated to all segments
2) segments (but the last one) are orphaned, so transmit path can not
get transmit queue number from the socket. This happens if GSO
segmentation is done before stacked device for example.
Result is we can send packets from a given TCP flow to different TX
queues (if using multiqueue NICS). This generates OOO problems and
spurious SACK & retransmits.
Fix this by keeping socket pointer set for all segments.
This means that every segment must also have a destructor, and the
original gso skb truesize must be split on all segments, to keep
precise sk->sk_wmem_alloc accounting.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I9d9d4216ec24ad4091535a9b9e811760cd949825
We can move th->check computation out of the loop, as compiler
doesn't know each skb initially share same tcp headers after
skb_segment()
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I7f81480604c4bd58f5cdd0be289233b9e6142a7f
I noticed that TSQ (TCP Small queues) was less effective when TSO is
turned off, and GSO is on. If BQL is not enabled, TSQ has then no
effect.
It turns out the GSO engine frees the original gso_skb at the time the
fragments are generated and queued to the NIC.
We should instead call the tcp_wfree() destructor for the last fragment,
to keep the flow control as intended in TSQ. This effectively limits
the number of queued packets on qdisc + NIC layers.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Idbe0206447bf979e012b6c4d5fe9e4fec10d5eb8
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>
Change-Id: I37d5e4d7c9ced1846385b6a04ae3ad134763a949
Taking socket spinlock in tcp_get_info() can deadlock, as
inet_diag_dump_icsk() holds the &hashinfo->ehash_locks[i],
while packet processing can use the reverse locking order.
We could avoid this locking for TCP_LISTEN states, but lockdep would
certainly get confused as all TCP sockets share same lockdep classes.
[ 523.722504] ======================================================
[ 523.728706] [ INFO: possible circular locking dependency detected ]
[ 523.734990] 4.1.0-dbg-DEV #1676 Not tainted
[ 523.739202] -------------------------------------------------------
[ 523.745474] ss/18032 is trying to acquire lock:
[ 523.750002] (slock-AF_INET){+.-...}, at: [<ffffffff81669d44>] tcp_get_info+0x2c4/0x360
[ 523.758129]
[ 523.758129] but task is already holding lock:
[ 523.763968] (&(&hashinfo->ehash_locks[i])->rlock){+.-...}, at: [<ffffffff816bcb75>] inet_diag_dump_icsk+0x1d5/0x6c0
[ 523.774661]
[ 523.774661] which lock already depends on the new lock.
[ 523.774661]
[ 523.782850]
[ 523.782850] the existing dependency chain (in reverse order) is:
[ 523.790326]
-> #1 (&(&hashinfo->ehash_locks[i])->rlock){+.-...}:
[ 523.796599] [<ffffffff811126bb>] lock_acquire+0xbb/0x270
[ 523.802565] [<ffffffff816f5868>] _raw_spin_lock+0x38/0x50
[ 523.808628] [<ffffffff81665af8>] __inet_hash_nolisten+0x78/0x110
[ 523.815273] [<ffffffff816819db>] tcp_v4_syn_recv_sock+0x24b/0x350
[ 523.822067] [<ffffffff81684d41>] tcp_check_req+0x3c1/0x500
[ 523.828199] [<ffffffff81682d09>] tcp_v4_do_rcv+0x239/0x3d0
[ 523.834331] [<ffffffff816842fe>] tcp_v4_rcv+0xa8e/0xc10
[ 523.840202] [<ffffffff81658fa3>] ip_local_deliver_finish+0x133/0x3e0
[ 523.847214] [<ffffffff81659a9a>] ip_local_deliver+0xaa/0xc0
[ 523.853440] [<ffffffff816593b8>] ip_rcv_finish+0x168/0x5c0
[ 523.859624] [<ffffffff81659db7>] ip_rcv+0x307/0x420
Lets use u64_sync infrastructure instead. As a bonus, 64bit
arches get optimized, as these are nop for them.
Fixes: 0df48c26d841 ("tcp: add tcpi_bytes_acked to tcp_info")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I50c833b77f41111a6fa3a57834c6311f95573754
This patch tracks the total number of inbound and outbound segments on a
TCP socket. One may use this number to have an idea on connection
quality when compared against the retransmissions.
RFC4898 named these : tcpEStatsPerfSegsIn and tcpEStatsPerfSegsOut
These are a 32bit field each and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)
Note that tp->segs_out was placed near tp->snd_nxt for good data
locality and minimal performance impact, while tp->segs_in was placed
near tp->bytes_received for the same reason.
Join work with Eric Dumazet.
Note that received SYN are accounted on the listener, but sent SYNACK
are not accounted.
Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Ic3e5daea102e13fb24c5fb1ce6913d5ece13c521
This patch tracks total number of payload bytes received on a TCP socket.
This is the sum of all changes done to tp->rcv_nxt
RFC4898 named this : tcpEStatsAppHCThruOctetsReceived
This is a 64bit field, and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)
Note that tp->bytes_received was placed near tp->rcv_nxt for
best data locality and minimal performance impact.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Eric Salo <salo@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: Ie1fec6455c8c6cf9ae3e2df09bf55abb56b57286
This patch tracks total number of bytes acked for a TCP socket.
This is the sum of all changes done to tp->snd_una, and allows
for precise tracking of delivered data.
RFC4898 named this : tcpEStatsAppHCThruOctetsAcked
This is a 64bit field, and can be fetched both from TCP_INFO
getsockopt() if one has a handle on a TCP socket, or from inet_diag
netlink facility (iproute2/ss patch will follow)
Note that tp->bytes_acked was placed near tp->snd_una for
best data locality and minimal performance impact.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Cc: Matt Mathis <mattmathis@google.com>
Cc: Eric Salo <salo@google.com>
Cc: Martin Lau <kafai@fb.com>
Cc: Chris Rapier <rapier@psc.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Change-Id: I975b11b049d6bde1b6802dc4331a9da93c371c9b
