The if_lock()/if_unlock() in next_to_run() adds a significant
overhead, because its called for every packet in busy loop of
pktgen_thread_worker(). (Thomas Graf originally pointed me
at this lock problem).
Removing these two "LOCK" operations should in theory save us approx
16ns (8ns x 2), as illustrated below we do save 16ns when removing
the locks and introducing RCU protection.
Performance data with CLONE_SKB==100000, TX-size=512, rx-usecs=30:
(single CPU performance, ixgbe 10Gbit/s, E5-2630)
* Prev : 5684009 pps --> 175.93ns (1/5684009*10^9)
* RCU-fix: 6272204 pps --> 159.43ns (1/6272204*10^9)
* Diff : +588195 pps --> -16.50ns
To understand this RCU patch, I describe the pktgen thread model
below.
In pktgen there is several kernel threads, but there is only one CPU
running each kernel thread. Communication with the kernel threads are
done through some thread control flags. This allow the thread to
change data structures at a know synchronization point, see main
thread func pktgen_thread_worker().
Userspace changes are communicated through proc-file writes. There
are three types of changes, general control changes "pgctrl"
(func:pgctrl_write), thread changes "kpktgend_X"
(func:pktgen_thread_write), and interface config changes "etcX@N"
(func:pktgen_if_write).
Userspace "pgctrl" and "thread" changes are synchronized via the mutex
pktgen_thread_lock, thus only a single userspace instance can run.
The mutex is taken while the packet generator is running, by pgctrl
"start". Thus e.g. "add_device" cannot be invoked when pktgen is
running/started.
All "pgctrl" and all "thread" changes, except thread "add_device",
communicate via the thread control flags. The main problem is the
exception "add_device", that modifies threads "if_list" directly.
Fortunately "add_device" cannot be invoked while pktgen is running.
But there exists a race between "rem_device_all" and "add_device"
(which normally don't occur, because "rem_device_all" waits 125ms
before returning). Background'ing "rem_device_all" and running
"add_device" immediately allow the race to occur.
The race affects the threads (list of devices) "if_list". The if_lock
is used for protecting this "if_list". Other readers are given
lock-free access to the list under RCU read sections.
Note, interface config changes (via proc) can occur while pktgen is
running, which worries me a bit. I'm assuming proc_remove() takes
appropriate locks, to assure no writers exists after proc_remove()
finish.
I've been running a script exercising the race condition (leading me
to fix the proc_remove order), without any issues. The script also
exercises concurrent proc writes, while the interface config is
getting removed.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid calling set_current_state() inside the busy-loop in
pktgen_thread_worker(). In case of pkt_dev->delay, then it is still
used/enabled in pktgen_xmit() via the spin() call.
The set_current_state(TASK_INTERRUPTIBLE) uses a xchg, which implicit
is LOCK prefixed. I've measured the asm LOCK operation to take approx
8ns on this E5-2630 CPU. Performance increase corrolate with this
measurement.
Performance data with CLONE_SKB==100000, rx-usecs=30:
(single CPU performance, ixgbe 10Gbit/s, E5-2630)
* Prev: 5454050 pps --> 183.35ns (1/5454050*10^9)
* Now: 5684009 pps --> 175.93ns (1/5684009*10^9)
* Diff: +229959 pps --> -7.42ns
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similarly to commit 43279500de ("packet: respect devices with
LLTX flag in direct xmit"), we can basically apply the very same
to pktgen. This will help testing against LLTX devices such as
dummy driver (or others), which only have a single netdevice txq
and would otherwise require locking their txq from pktgen side
while e.g. in dummy case, we would not need any locking. Fix this
by making use of HARD_TX_{UN,}LOCK API, so that NETIF_F_LLTX will
be respected.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Similarly as in commit 8e2f1a63f2 ("packet: fix packet_direct_xmit
for BQL enabled drivers"), we test for __QUEUE_STATE_STACK_XOFF bit
in pktgen's xmit, which would not fully fill the device's TX ring for
BQL drivers that use netdev_tx_sent_queue(). Fix is to use, similarly
as we do in packet sockets, netif_xmit_frozen_or_drv_stopped() test.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The documentation misses a few of the supported flags. Fix this. Also
respect the dependency to CONFIG_XFRM for the IPSEC flag.
Cc: Fan Du <fan.du@windriver.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The 'out' label is just a relict from previous times as pgctrl_write()
had multiple error paths. Get rid of it and simply return right away
on errors.
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If a privileged user writes an empty string to /proc/net/pktgen/pgctrl
the code for stripping the (then non-existent) '\n' actually writes the
zero byte at index -1 of data[]. The then still uninitialized array will
very likely fail the command matching tests and the pr_warning() at the
end will therefore leak stack bytes to the kernel log.
Fix those issues by simply ensuring we're passed a non-empty string as
the user API apparently expects a trailing '\n' for all commands.
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ether_addr_copy instead of memcpy(a, b, ETH_ALEN) to
save some cycles on arm and powerpc.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
0-DAY kernel build testing backend reported below error:
All error/warnings:
net/core/pktgen.c: In function 'pktgen_if_write':
>> >> net/core/pktgen.c:1487:10: error: 'struct pktgen_dev' has no member named 'spi'
>> >> net/core/pktgen.c:1488:43: error: 'struct pktgen_dev' has no member named 'spi'
Fix this by encapuslating the code with CONFIG_XFRM.
Cc: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
If user run pktgen plus ipsec by using spi, show spi value
properly when cat /proc/net/pktgen/ethX
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Introduce xfrm_state_lookup_byspi to find user specified by custom
from "pgset spi xxx". Using this scheme, any flow regardless its
saddr/daddr could be transform by SA specified with configurable
spi.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
IPsec tunnel mode encapuslation needs to set outter ip header
with right protocol/ttl/id value with regard to skb->dst->child.
Looking up a rt in a standard way is absolutely wrong for every
packet transmission. In a simple way, construct a dst by setting
neccessary information to make tunnel mode encapuslation working.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
User could set specific SPI value to arm pktgen flow with IPsec
transformation, instead of looking up SA by sadr/daddr. The reaseon
to do so is because current state lookup scheme is both slow and, most
important of all, in fact pktgen doesn't need to match any SA state
addresses information, all it needs is the SA transfromation shell to
do the encapuslation.
And this option also provide user an alternative to using pktgen
test existing SA without creating new ones.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
so /proc/net/xfrm_stat could give user clue about what's
wrong in this process.
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
commit a553e4a631 ("[PKTGEN]: IPSEC support")
tried to support IPsec ESP transport transformation for pktgen, but acctually
this doesn't work at all for two reasons(The orignal transformed packet has
bad IPv4 checksum value, as well as wrong auth value, reported by wireshark)
- After transpormation, IPv4 header total length needs update,
because encrypted payload's length is NOT same as that of plain text.
- After transformation, IPv4 checksum needs re-caculate because of payload
has been changed.
With this patch, armmed pktgen with below cofiguration, Wireshark is able to
decrypted ESP packet generated by pktgen without any IPv4 checksum error or
auth value error.
pgset "flag IPSEC"
pgset "flows 1"
Signed-off-by: Fan Du <fan.du@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fixes this on PowerPC (at least):
net/core/pktgen.c: In function 'fill_packet_ipv6':
net/core/pktgen.c:2906:3: error: implicit declaration of function 'csum_ipv6_magic' [-Werror=implicit-function-declaration]
udph->check = ~csum_ipv6_magic(&iph->saddr, &iph->daddr, udplen, IPPROTO_UDP, 0);
^
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
UDP checksums are optional, hence pktgen has been omitting them in
favour of performance. The optional flag UDPCSUM enables UDP
checksumming. If the output device supports hardware checksumming
the skb is prepared and marked CHECKSUM_PARTIAL, otherwise the
checksum is generated in software.
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently allow for numa-node aware skb allocation only within the
fill_packet_ipv4() path, but not in fill_packet_ipv6(). Consolidate that
code to a common allocation helper to enable numa-node aware skb
allocation for ipv6, and use it in both paths. This also makes both
functions a bit more readable.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_set_network_header() expects an offset based on the data pointer
whereas skb_tail_offset() also includes the headroom. This resulted
in the ip header being written in a wrong location.
Use return values of skb_put() directly and rely on skb->len to
set mac, network, and transport header.
Cc: Simon Horman <horms@verge.net.au>
Cc: Daniel Borkmann <dborkmann@redhat.com>
Assisted-by: Daniel Borkmann <dborkmann@redhat.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Daniel Borkmann <dborkmann@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This corrects an regression introduced by "net: Use 16bits for *_headers
fields of struct skbuff" when NET_SKBUFF_DATA_USES_OFFSET is not set. In
that case skb->tail will be a pointer however skb->network_header is now
an offset.
This patch corrects the problem by adding a wrapper to return skb tail as
an offset regardless of the value of NET_SKBUFF_DATA_USES_OFFSET. It seems
that skb->tail that this offset may be more than 64k and some care has been
taken to treat such cases as an error.
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
So far, only net_device * could be passed along with netdevice notifier
event. This patch provides a possibility to pass custom structure
able to provide info that event listener needs to know.
Signed-off-by: Jiri Pirko <jiri@resnulli.us>
v2->v3: fix typo on simeth
shortened dev_getter
shortened notifier_info struct name
v1->v2: fix notifier_call parameter in call_netdevice_notifier()
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull VFS updates from Al Viro,
Misc cleanups all over the place, mainly wrt /proc interfaces (switch
create_proc_entry to proc_create(), get rid of the deprecated
create_proc_read_entry() in favor of using proc_create_data() and
seq_file etc).
7kloc removed.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (204 commits)
don't bother with deferred freeing of fdtables
proc: Move non-public stuff from linux/proc_fs.h to fs/proc/internal.h
proc: Make the PROC_I() and PDE() macros internal to procfs
proc: Supply a function to remove a proc entry by PDE
take cgroup_open() and cpuset_open() to fs/proc/base.c
ppc: Clean up scanlog
ppc: Clean up rtas_flash driver somewhat
hostap: proc: Use remove_proc_subtree()
drm: proc: Use remove_proc_subtree()
drm: proc: Use minor->index to label things, not PDE->name
drm: Constify drm_proc_list[]
zoran: Don't print proc_dir_entry data in debug
reiserfs: Don't access the proc_dir_entry in r_open(), r_start() r_show()
proc: Supply an accessor for getting the data from a PDE's parent
airo: Use remove_proc_subtree()
rtl8192u: Don't need to save device proc dir PDE
rtl8187se: Use a dir under /proc/net/r8180/
proc: Add proc_mkdir_data()
proc: Move some bits from linux/proc_fs.h to linux/{of.h,signal.h,tty.h}
proc: Move PDE_NET() to fs/proc/proc_net.c
...
Remove duplicate statements by using do-while loop instead of while loop.
- A;
- while (e) {
+ do {
A;
- }
+ } while (e);
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use preferable function name which implies using a pseudo-random
number generator.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The only part of proc_dir_entry the code outside of fs/proc
really cares about is PDE(inode)->data. Provide a helper
for that; static inline for now, eventually will be moved
to fs/proc, along with the knowledge of struct proc_dir_entry
layout.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
proc_net_remove is only used to remove proc entries
that under /proc/net,it's not a general function for
removing proc entries of netns. if we want to remove
some proc entries which under /proc/net/stat/, we still
need to call remove_proc_entry.
this patch use remove_proc_entry to replace proc_net_remove.
we can remove proc_net_remove after this patch.
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/intel/e1000e/ethtool.c
drivers/net/vmxnet3/vmxnet3_drv.c
drivers/net/wireless/iwlwifi/dvm/tx.c
net/ipv6/route.c
The ipv6 route.c conflict is simple, just ignore the 'net' side change
as we fixed the same problem in 'net-next' by eliminating cached
neighbours from ipv6 routes.
The e1000e conflict is an addition of a new statistic in the ethtool
code, trivial.
The vmxnet3 conflict is about one change in 'net' removing a guarding
conditional, whilst in 'net-next' we had a netdev_info() conversion.
The iwlwifi conflict is dealing with a WARN_ON() conversion in
'net-next' vs. a revert happening in 'net'.
Signed-off-by: David S. Miller <davem@davemloft.net>
The return value of pktgen_add_device() is not checked, so
even if we fail to add some device, for example, non-exist one,
we still see "OK:...". This patch fixes it.
After this patch, I got:
# echo "add_device non-exist" > /proc/net/pktgen/kpktgend_0
-bash: echo: write error: No such device
# cat /proc/net/pktgen/kpktgend_0
Running:
Stopped:
Result: ERROR: can not add device non-exist
# echo "add_device eth0" > /proc/net/pktgen/kpktgend_0
# cat /proc/net/pktgen/kpktgend_0
Running:
Stopped: eth0
Result: OK: add_device=eth0
(Candidate for -stable)
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
v3: make pktgen_threads list per-namespace
v2: remove a useless check
This patch add net namespace to pktgen, so that
we can use pktgen in different namespaces.
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some years ago, the ktime_t helper functions ktime_now() and ktime_lt()
have been introduced. Instead of defining them inside pktgen.c, they
should either use ktime_t library functions or, if not available, they
should be defined in ktime.h, so that also others can benefit from them.
ktime_compare() is introduced with a similar notion as in timespec_compare().
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Stephen Hemminger <shemminger@vyatta.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
It is weird to display IPv4 address in %x format, what's more,
IPv6 address is disaplayed in human-readable format too. So,
make it human-readable.
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ETH_ZLEN is too small for IPv6, so this default value is not
suitable.
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For IPv6, sizeof(struct ipv6hdr) = 40, thus the following
expression will result negative:
datalen = pkt_dev->cur_pkt_size - 14 -
sizeof(struct ipv6hdr) - sizeof(struct udphdr) -
pkt_dev->pkt_overhead;
And, the check "if (datalen < sizeof(struct pktgen_hdr))" will be
passed as "datalen" is promoted to unsigned, therefore will cause
a crash later.
This is a quick fix by checking if "datalen" is negative. The following
patch will increase the default value of 'min_pkt_size' for IPv6.
This bug should exist for a long time, so Cc -stable too.
Cc: <stable@vger.kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If vlan option is being specified in the pktgen and packet size
being requested is less than 46 bytes, despite being illogical
request, pktgen should not crash the kernel.
BUG: unable to handle kernel paging request at ffff88021fb82000
Process kpktgend_0 (pid: 1184, threadinfo ffff880215f1a000, task ffff880218544530)
Call Trace:
[<ffffffffa0637cd2>] ? pktgen_finalize_skb+0x222/0x300 [pktgen]
[<ffffffff814f0084>] ? build_skb+0x34/0x1c0
[<ffffffffa0639b11>] pktgen_thread_worker+0x5d1/0x1790 [pktgen]
[<ffffffffa03ffb10>] ? igb_xmit_frame_ring+0xa30/0xa30 [igb]
[<ffffffff8107ba20>] ? wake_up_bit+0x40/0x40
[<ffffffff8107ba20>] ? wake_up_bit+0x40/0x40
[<ffffffffa0639540>] ? spin+0x240/0x240 [pktgen]
[<ffffffff8107b4e3>] kthread+0x93/0xa0
[<ffffffff81615de4>] kernel_thread_helper+0x4/0x10
[<ffffffff8107b450>] ? flush_kthread_worker+0x80/0x80
[<ffffffff81615de0>] ? gs_change+0x13/0x13
The root cause of why pktgen is not able to handle this case is due
to comparison of signed (datalen) and unsigned data (sizeof), which
eventually passes a huge number to skb_put().
Signed-off-by: Nishank Trivedi <nistrive@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit c57b546840 (pktgen: fix crash at module unload) did a very poor
job with list primitives.
1) list_splice() arguments were in the wrong order
2) list_splice(list, head) has undefined behavior if head is not
initialized.
3) We should use the list_splice_init() variant to clear pktgen_threads
list.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert printk(KERN_DEBUG to pr_debug which can
enable dynamic debugging.
Remove embedded prefixes from the conversions as
pr_fmt adds them.
Align arguments.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Standardize the net core ratelimited logging functions.
Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.
Signed-off-by: Joe Perches <joe@perches.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>
Fabian Frederick