CAIF HSI uses a timer for inactivity. Upon timeout HSI-wake signaling
is initiated to allow power-down of the HSI block.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some platforms do not allow to put HSI block into low-power
mode when FIFO is not empty. The patch flushes (by reading)
FIFO at wake down sequence. Asynchronous read and write is
implemented for that. As a side effect this will also greatly
improve performance.
Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
To ease skb->truesize sanitization, its better to be able to localize
all references to skb frags size.
Define accessors : skb_frag_size() to fetch frag size, and
skb_frag_size_{set|add|sub}() to manipulate it.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fragmented multicast frames are delivered to a single macvlan port,
because ip defrag logic considers other samples are redundant.
Implement a defrag step before trying to send the multicast frame.
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The BerliOS project, which currently hosts our mailinglist, will
close with the end of the year. Now take the chance and remove all
occurrences of the mailinglist address from the source files.
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add configuration setting for drivers to turn spoof checking on or off
for discrete VFs.
v2 - Fix indentation problem, wrap the ifla_vf_info structure in
#ifdef __KERNEL__ to prevent user space from accessing and
change function paramater for the spoof check setting netdev
op from u8 to bool.
v3 - Preset spoof check setting to -1 so that user space tools such
as ip can detect that the driver didn't report a spoofcheck
setting. Prevents incorrect display of spoof check settings
for drivers that don't report it.
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Reuse the already existing struct nl80211_sta_flag_update to specify
both, a flag mask and the flag set itself. This means
nl80211_sta_flag_update is now used for setting station flags and also
for getting station flags.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
mac80211 already filled in the MCS rate info for rx'ed frames but tx'ed
frames that are sent to a monitor interface during the status callback
lack this information.
Add the radiotap fields for MCS info to ieee80211_tx_status_rtap_hdr
and populate them when sending tx'ed frames to the monitors.
The needed headroom is only extended by one byte since we don't include
legacy rate information in the rtap header for HT frames.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
skb truesize currently accounts for sk_buff struct and part of skb head.
kmalloc() roundings are also ignored.
Considering that skb_shared_info is larger than sk_buff, its time to
take it into account for better memory accounting.
This patch introduces SKB_TRUESIZE(X) macro to centralize various
assumptions into a single place.
At skb alloc phase, we put skb_shared_info struct at the exact end of
skb head, to allow a better use of memory (lowering number of
reallocations), since kmalloc() gives us power-of-two memory blocks.
Unless SLUB/SLUB debug is active, both skb->head and skb_shared_info are
aligned to cache lines, as before.
Note: This patch might trigger performance regressions because of
misconfigured protocol stacks, hitting per socket or global memory
limits that were previously not reached. But its a necessary step for a
more accurate memory accounting.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Andi Kleen <ak@linux.intel.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch exposes the tos value for the TCP sockets when the TOS flag
is requested in the ext_flags for the inet_diag request. This would mainly be
used to expose TOS values for both for TCP and UDP sockets. Currently it is
supported for TCP. When netlink support for UDP would be added the support
to expose the TOS values would alse be done. For IPV4 tos value is exposed
and for IPV6 tclass value is exposed.
Signed-off-by: Murali Raja <muralira@google.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We can now move the radiotap header parsing into
ieee80211_monitor_start_xmit(). This moves it out of
the hotpath, and also helps the code since now the
radiotap header will no longer be present in
ieee80211_xmit() etc. which is easier to understand.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The purpose of this is two-fold:
1) by moving it out of tx_data.flags, we can in
another patch move the radiotap parsing so it
no longer is in the hotpath
2) if a device implements fragmentation but can
optionally skip it, the radiotap request for
not doing fragmentation may be honoured
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
To avoid ifdefs in the other code that supports DCB notifiers
add stub routines. This method seems popular in other net code
for example 8021Q.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add DCBX mode to event notifiers so listeners can learn
currently enabled mode.
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ifindex instead of ifname in the DCB app ring. This makes for a smaller
data structure and faster comparisons. It also avoids possible issues when
a net device is renamed.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://github.com/davem330/net:
pch_gbe: Fixed the issue on which a network freezes
pch_gbe: Fixed the issue on which PC was frozen when link was downed.
make PACKET_STATISTICS getsockopt report consistently between ring and non-ring
net: xen-netback: correctly restart Tx after a VM restore/migrate
bonding: properly stop queuing work when requested
can bcm: fix incomplete tx_setup fix
RDSRDMA: Fix cleanup of rds_iw_mr_pool
net: Documentation: Fix type of variables
ibmveth: Fix oops on request_irq failure
ipv6: nullify ipv6_ac_list and ipv6_fl_list when creating new socket
cxgb4: Fix EEH on IBM P7IOC
can bcm: fix tx_setup off-by-one errors
MAINTAINERS: tehuti: Alexander Indenbaum's address bounces
dp83640: reduce driver noise
ptp: fix L2 event message recognition
Add the ability to disable PCI-E MPS turning and using the BIOS
configured MPS defaults. Due to the number of issues recently
discovered on some x86 chipsets, make this the default behavior.
Also, add the option for peer to peer DMA MPS configuration. Peer to
peer DMA is outside the scope of this patch, but MPS configuration could
prevent it from working by having the MPS on one root port different
than the MPS on another. To work around this, simply make the system
wide MPS the smallest possible value (128B).
Signed-off-by: Jon Mason <mason@myri.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
tx params should be configured per interface.
add ieee80211_vif param to the conf_tx callback,
and change all the drivers that use this callback.
The following spatch was used:
@rule1@
struct ieee80211_ops ops;
identifier conf_tx_op;
@@
ops.conf_tx = conf_tx_op;
@rule2@
identifier rule1.conf_tx_op;
identifier hw, queue, params;
@@
conf_tx_op (
- struct ieee80211_hw *hw,
+ struct ieee80211_hw *hw, struct ieee80211_vif *vif,
u16 queue,
const struct ieee80211_tx_queue_params *params) {...}
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Recently mac80211 was changed to use nullfunc instead of probe
request for connection monitoring for tx ack status reporting
hardwares. Sometimes in congested network, STA got disconnected
quickly after the association. It was observered that the rate
control was not adopted to environment due to minimal transmission.
As the nullfunc are used for monitoring purpose, these frames should
not be sacrificed for rate control updation. So it is better to send
the monitoring null func frames at minimum rate that could help to
retain the connection.
Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add a gpio setup function which gives a chance to set up
platform specific configuration such as pin multiplexing,
input/output direction at the runtime or booting time.
Signed-off-by: Sangwook Lee <sangwook.lee@linaro.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Allow injected unicast frames to be sent without having to wait
for an ACK.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
removing obsoleted sysctl,
ip_rt_gc_interval variable no longer used since 2.6.38
Signed-off-by: Vasily Averin <vvs@sw.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
This repairs problem with compile library in userspace (libnl).
Signed-off-by: Jiří Župka <jzupka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allows ss command (iproute2) to display "ecnseen" if at least one packet
with ECT(0) or ECT(1) or ECN was received by this socket.
"ecn" means ECN was negotiated at session establishment (TCP level)
"ecnseen" means we received at least one packet with ECT fields set (IP
level)
ss -i
...
ESTAB 0 0 192.168.20.110:22 192.168.20.144:38016
ino:5950 sk:f178e400
mem:(r0,w0,f0,t0) ts sack ecn ecnseen bic wscale:7,8 rto:210
rtt:12.5/7.5 cwnd:10 send 9.3Mbps rcv_space:14480
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'irq-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
irq: Fix check for already initialized irq_domain in irq_domain_add
irq: Add declaration of irq_domain_simple_ops to irqdomain.h
* 'x86-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
x86/rtc: Don't recursively acquire rtc_lock
* 'sched-urgent-for-linus' of git://tesla.tglx.de/git/linux-2.6-tip:
posix-cpu-timers: Cure SMP wobbles
sched: Fix up wchan borkage
sched/rt: Migrate equal priority tasks to available CPUs
With the addition of uAPSD and driver buffering
the powersave handling has gotten quite complex.
Add a section to the documentation to explain it
for anyone wanting to implement it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
iwlwifi has a separate EOSP notification from
the device, and to make use of that properly
it needs to be passed to mac80211. To be able
to mix with tx_status_irqsafe and rx_irqsafe
it also needs to be an "_irqsafe" version in
the sense that it goes through the tasklet,
the actual flag clearing would be IRQ-safe
but doing it directly would cause reordering
issues.
This is needed in the case of a P2P GO going
into an absence period without transmitting
any frames that should be driver-released as
in this case there's no other way to inform
mac80211 that the service period ended. Note
that for drivers that don't use the _irqsafe
functions another version of this function
will be required.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
iwlwifi needs to know the number of frames that are
going to be sent to a station while it is asleep so
it can properly handle the uCode blocking of that
station.
Before uAPSD, we got by by telling the device that
a single frame was going to be released whenever we
encountered IEEE80211_TX_CTL_POLL_RESPONSE. With
uAPSD, however, that is no longer possible since
there could be more than a single frame.
To support this model, add a new callback to notify
drivers when frames are going to be released.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
If a PS-poll frame is retried (but was received)
there is no way to detect that since it has no
sequence number. As a consequence, the standard
asks us to not react to PS-poll frames until the
response to one made it out (was ACKed or lost).
Implement this by using the WLAN_STA_SP flags to
also indicate a PS-Poll "service period" and the
IEEE80211_TX_STATUS_EOSP flag for the response
packet to indicate the end of the "SP" as usual.
We could use separate flags, but that will most
likely completely confuse drivers, and while the
standard doesn't exclude simultaneously polling
using uAPSD and PS-Poll, doing that seems quite
problematic.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add uAPSD support to mac80211. This is probably not
possible with all devices, so advertising it with
the cfg80211 flag will be left up to drivers that
want it.
Due to my previous patches it is now a fairly
straight-forward extension. Drivers need to have
accurate TX status reporting for the EOSP frame.
For drivers that buffer themselves, the provided
APIs allow releasing the right number of frames,
but then drivers need to set EOSP and more-data
themselves. This is documented in more detail in
the new code itself.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
If there are frames for a station buffered in
the driver, mac80211 announces those in the TIM
IE but there's no way to release them. Add new
API to release such frames and use it when the
station polls for a frame.
Since the API will soon also be used for uAPSD
it is easily extensible.
Note that before this change drivers announcing
driver-buffered frames in the TIM bit actually
will respond to a PS-Poll with a potentially
lower priority frame (if there are any frames
buffered in mac80211), after this patch a driver
that hasn't been changed will no longer respond
at all. This only affects ath9k, which will need
to be fixed to implement the new API.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For uAPSD support we'll need to have per-AC PS
buffers. As this is a major undertaking, split
the buffers before really adding support for
uAPSD. This already makes some reference to the
uapsd_queues variable, but for now that will
never be non-zero.
Since book-keeping is complicated, also change
the logic for keeping a maximum of frames only
and allow 64 frames per AC (up from 128 for a
station).
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For uAPSD implementation, it is necessary to know on
which ACs frames are buffered. mac80211 obviously
knows about the frames it has buffered itself, but
with aggregation many drivers buffer frames. Thus,
mac80211 needs to be informed about this.
For now, since we don't have APSD in any form, this
will unconditionally set the TIM bit for the station
but later with uAPSD only some ACs might cause the
TIM bit to be set.
ath9k is the only driver using this API and I only
modify it in the most basic way, it won't be able
to implement uAPSD with this yet. But it can't do
that anyway since there's no way to selectively
release frames to the peer yet.
Since drivers will buffer frames per TID, let them
inform mac80211 on a per TID basis, mac80211 will
then sort out the AC mapping itself.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When adding a TDLS peer STA, mark it with a new flag in both nl80211 and
mac80211. Before adding a peer, make sure the wiphy supports TDLS and
our operating mode is appropriate (managed).
In addition, make sure all peers are removed on disassociation.
A TDLS peer is first added just before link setup is initiated. In later
setup stages we have more info about peer supported rates, capabilities,
etc. This info is reported via nl80211_set_station().
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Cc: Kalyan C Gaddam <chakkal@iit.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Register and implement the TDLS cfg80211 callback functions.
Internally prepare and send TDLS management frames. We incorporate
local STA capabilities and supported rates with extra IEs given by
usermode. The resulting packet is either encapsulated in a data frame,
or assembled as an action frame. It is transmitted either directly or
through the AP, as mandated by the TDLS specification.
Declare support for the TDLS external setup wiphy capability. This
tells usermode to handle link setup and discovery on its own, and use the
kernel driver for sending TDLS mgmt packets.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Cc: Kalyan C Gaddam <chakkal@iit.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Relocate the mesh implementation of adding the (extended) supported
rates IE to util.c, anticipating its use by other parts of mac80211.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Cc: Kalyan C Gaddam <chakkal@iit.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add support for sending high-level TDLS commands and TDLS frames via
NL80211_CMD_TDLS_OPER and NL80211_CMD_TDLS_MGMT, respectively. Add
appropriate cfg80211 callbacks for lower level drivers.
Add wiphy capability flags for TDLS support and advertise them via
nl80211.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Cc: Kalyan C Gaddam <chakkal@iit.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Currently, when hostapd sets the station as authorized
we also overwrite its uAPSD parameter. This obviously
leads to buggy behaviour (later, with my patches that
actually add uAPSD support). To fix this, only apply
those parameters if they were actually set in nl80211,
and to achieve that add a bitmap of things to apply.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
David reported:
Attached below is a watered-down version of rt/tst-cpuclock2.c from
GLIBC. Just build it with "gcc -o test test.c -lpthread -lrt" or
similar.
Run it several times, and you will see cases where the main thread
will measure a process clock difference before and after the nanosleep
which is smaller than the cpu-burner thread's individual thread clock
difference. This doesn't make any sense since the cpu-burner thread
is part of the top-level process's thread group.
I've reproduced this on both x86-64 and sparc64 (using both 32-bit and
64-bit binaries).
For example:
[davem@boricha build-x86_64-linux]$ ./test
process: before(0.001221967) after(0.498624371) diff(497402404)
thread: before(0.000081692) after(0.498316431) diff(498234739)
self: before(0.001223521) after(0.001240219) diff(16698)
[davem@boricha build-x86_64-linux]$
The diff of 'process' should always be >= the diff of 'thread'.
I make sure to wrap the 'thread' clock measurements the most tightly
around the nanosleep() call, and that the 'process' clock measurements
are the outer-most ones.
---
#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <fcntl.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
static pthread_barrier_t barrier;
static void *chew_cpu(void *arg)
{
pthread_barrier_wait(&barrier);
while (1)
__asm__ __volatile__("" : : : "memory");
return NULL;
}
int main(void)
{
clockid_t process_clock, my_thread_clock, th_clock;
struct timespec process_before, process_after;
struct timespec me_before, me_after;
struct timespec th_before, th_after;
struct timespec sleeptime;
unsigned long diff;
pthread_t th;
int err;
err = clock_getcpuclockid(0, &process_clock);
if (err)
return 1;
err = pthread_getcpuclockid(pthread_self(), &my_thread_clock);
if (err)
return 1;
pthread_barrier_init(&barrier, NULL, 2);
err = pthread_create(&th, NULL, chew_cpu, NULL);
if (err)
return 1;
err = pthread_getcpuclockid(th, &th_clock);
if (err)
return 1;
pthread_barrier_wait(&barrier);
err = clock_gettime(process_clock, &process_before);
if (err)
return 1;
err = clock_gettime(my_thread_clock, &me_before);
if (err)
return 1;
err = clock_gettime(th_clock, &th_before);
if (err)
return 1;
sleeptime.tv_sec = 0;
sleeptime.tv_nsec = 500000000;
nanosleep(&sleeptime, NULL);
err = clock_gettime(th_clock, &th_after);
if (err)
return 1;
err = clock_gettime(my_thread_clock, &me_after);
if (err)
return 1;
err = clock_gettime(process_clock, &process_after);
if (err)
return 1;
diff = process_after.tv_nsec - process_before.tv_nsec;
printf("process: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
process_before.tv_sec, process_before.tv_nsec,
process_after.tv_sec, process_after.tv_nsec, diff);
diff = th_after.tv_nsec - th_before.tv_nsec;
printf("thread: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
th_before.tv_sec, th_before.tv_nsec,
th_after.tv_sec, th_after.tv_nsec, diff);
diff = me_after.tv_nsec - me_before.tv_nsec;
printf("self: before(%lu.%.9lu) after(%lu.%.9lu) diff(%lu)\n",
me_before.tv_sec, me_before.tv_nsec,
me_after.tv_sec, me_after.tv_nsec, diff);
return 0;
}
This is due to us using p->se.sum_exec_runtime in
thread_group_cputime() where we iterate the thread group and sum all
data. This does not take time since the last schedule operation (tick
or otherwise) into account. We can cure this by using
task_sched_runtime() at the cost of having to take locks.
This also means we can (and must) do away with
thread_group_sched_runtime() since the modified thread_group_cputime()
is now more accurate and would deadlock when called from
thread_group_sched_runtime().
Aside of that it makes the function safe on 32 bit systems. The old
code added t->se.sum_exec_runtime unprotected. sum_exec_runtime is a
64bit value and could be changed on another cpu at the same time.
Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: stable@kernel.org
Link: http://lkml.kernel.org/r/1314874459.7945.22.camel@twins
Tested-by: David Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The IEEE 1588 standard defines two kinds of messages, event and general
messages. Event messages require time stamping, and general do not. When
using UDP transport, two separate ports are used for the two message
types.
The BPF designed to recognize event messages incorrectly classifies L2
general messages as event messages. This commit fixes the issue by
extending the filter to check the message type field for L2 PTP packets.
Event messages are be distinguished from general messages by testing
the "general" bit.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Cc: <stable@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add an event to monitor comm value changes of tasks. Such an event
becomes vital, if someone desires to control threads of a process in
different manner.
A natural characteristic of threads is its comm value, and helpfully
application developers have an opportunity to change it in runtime.
Reporting about such events via proc connector allows to fine-grain
monitoring and control potentials, for instance a process control daemon
listening to proc connector and following comm value policies can place
specific threads to assigned cgroup partitions.
It might be possible to achieve a pale partial one-shot likeness without
this update, if an application changes comm value of a thread generator
task beforehand, then a new thread is cloned, and after that proc
connector listener gets the fork event and reads new thread's comm value
from procfs stat file, but this change visibly simplifies and extends the
matter.
Signed-off-by: Vladimir Zapolskiy <vzapolskiy@gmail.com>
Acked-by: Evgeniy Polyakov <zbr@ioremap.net>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since commit 7361c36c52 (af_unix: Allow credentials to work across
user and pid namespaces) af_unix performance dropped a lot.
This is because we now take a reference on pid and cred in each write(),
and release them in read(), usually done from another process,
eventually from another cpu. This triggers false sharing.
# Events: 154K cycles
#
# Overhead Command Shared Object Symbol
# ........ ....... .................. .........................
#
10.40% hackbench [kernel.kallsyms] [k] put_pid
8.60% hackbench [kernel.kallsyms] [k] unix_stream_recvmsg
7.87% hackbench [kernel.kallsyms] [k] unix_stream_sendmsg
6.11% hackbench [kernel.kallsyms] [k] do_raw_spin_lock
4.95% hackbench [kernel.kallsyms] [k] unix_scm_to_skb
4.87% hackbench [kernel.kallsyms] [k] pid_nr_ns
4.34% hackbench [kernel.kallsyms] [k] cred_to_ucred
2.39% hackbench [kernel.kallsyms] [k] unix_destruct_scm
2.24% hackbench [kernel.kallsyms] [k] sub_preempt_count
1.75% hackbench [kernel.kallsyms] [k] fget_light
1.51% hackbench [kernel.kallsyms] [k]
__mutex_lock_interruptible_slowpath
1.42% hackbench [kernel.kallsyms] [k] sock_alloc_send_pskb
This patch includes SCM_CREDENTIALS information in a af_unix message/skb
only if requested by the sender, [man 7 unix for details how to include
ancillary data using sendmsg() system call]
Note: This might break buggy applications that expected SCM_CREDENTIAL
from an unaware write() system call, and receiver not using SO_PASSCRED
socket option.
If SOCK_PASSCRED is set on source or destination socket, we still
include credentials for mere write() syscalls.
Performance boost in hackbench : more than 50% gain on a 16 thread
machine (2 quad-core cpus, 2 threads per core)
hackbench 20 thread 2000
4.228 sec instead of 9.102 sec
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
