Eric Dumazet 98e09386c0 tcp: tsq: restore minimal amount of queueing ... 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>		2013-11-14 16:25:14 -05:00
..
ABI	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2013-11-13 17:40:34 +09:00
accounting
acpi	gpiolib / ACPI: document the GPIO descriptor based interface	2013-10-19 23:32:50 +02:00
aoe	aoe: remove do-nothing NAME="%k" term from example udev rules	2013-09-11 15:59:28 -07:00
arm	Allwinner sunXi SoCs machine additions for 3.13	2013-10-28 10:19:38 -07:00
arm64	arm64: Use 42-bit address space with 64K pages	2013-11-05 17:23:52 +00:00
auxdisplay
backlight	backlight: lp855x_bl: support new LP8555 device	2013-11-13 12:09:14 +09:00
blackfin
block	block: change config option name for cmdline partition parsing	2013-09-30 14:31:02 -07:00
blockdev
bus-devices
cdrom
cgroups	memcg: support hierarchical memory.numa_stats	2013-11-13 12:09:06 +09:00
connector	connector - documentation: simplify netlink message length assignment	2013-10-02 16:03:51 -04:00
console
cpu-freq
cpuidle
cris
crypto
development-process
device-mapper	dm: add statistics support	2013-09-05 20:46:06 -04:00
devicetree	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2013-11-13 17:40:34 +09:00
DocBook	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next	2013-11-13 17:40:34 +09:00
driver-model	spi: Updates for v3.13	2013-11-12 15:01:39 +09:00
dvb
early-userspace
EDID
extcon	extcon: Simplify extcon_dev_register() prototype by removing unnecessary parameter	2013-09-27 09:37:01 +09:00
fault-injection
fb
filesystems	Merge branch 'akpm' (patches from Andrew Morton)	2013-11-13 15:45:43 +09:00
firmware_class
fmc	doc: Fix typo "is is" in Documentations	2013-08-27 10:50:52 +02:00
frv
hid
hwmon	hwmon: (pmbus/ltc2978): Add support for LTC2978A	2013-10-18 09:12:03 -07:00
i2c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
i2o
ia64
ide
infiniband
input	Merge branch 'master' into for-3.12/upstream	2013-09-04 10:49:57 +02:00
ioctl	ALSA: add DICE driver	2013-10-17 21:18:32 +02:00
isdn
ja_JP
kbuild	kconfig: do not allow more than one symbol to have 'option modules'	2013-09-05 11:10:08 +02:00
kdump
ko_KR
laptops	thinkpad-acpi: Add mute and mic-mute LED functionality	2013-10-17 14:38:44 +02:00
leds	Documentation: leds-lp5521,lp5523: update device attribute information	2013-08-26 17:22:13 -07:00
m68k
make
memory-devices
metag
mic	misc: mic: Enable OSPM suspend and resume support.	2013-10-05 18:01:42 -07:00
mips
misc-devices
mmc
mn10300
mtd	doc: Fix typo "is is" in Documentations	2013-08-27 10:50:52 +02:00
namespaces
netlabel
networking	tcp: tsq: restore minimal amount of queueing	2013-11-14 16:25:14 -05:00
nfc
parisc
PCI
pcmcia
power	power: Documentation: Update s2ram link	2013-08-27 10:54:52 +02:00
powerpc	powerpc: Update the 00-Index in Documentation/powerpc	2013-08-27 14:44:27 +10:00
pps	USB: serial: invoke dcd_change ldisc's handler.	2013-09-26 09:45:40 -07:00
prctl
pti
ptp	ptp: add the PTP_SYS_OFFSET ioctl to the testptp program	2013-09-23 16:46:17 -04:00
rapidio
RCU	rcu: Fix occurrence of "the the" in checklist.txt	2013-09-25 10:07:02 -07:00
s390	s390/s390dbf: add debug_level_enabled() function	2013-10-24 17:16:53 +02:00
scheduler	H8/300 has been dead for several years, the kernel for it has	2013-11-12 14:13:14 +09:00
scsi	SCSI misc on 20130915	2013-09-15 17:41:30 -04:00
security
serial	serial: core: delete .set_wake() callback	2013-10-16 13:16:19 -07:00
sh
sound	ALSA: Fix typo in documentation/alsa	2013-10-29 11:38:04 +01:00
spi
sysctl	vsprintf: check real user/group id for %pK	2013-11-13 12:09:14 +09:00
target
thermal	thermal: thermal_core: allow binding with limits on bind_params	2013-09-03 09:10:24 -04:00
timers
tpm
trace	Documentation/trace/tracepoints.txt: add links to TRACE_EVENT documentation	2013-11-13 12:09:32 +09:00
usb
vDSO
video4linux
virtual	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
vm	Documentation/vm/zswap.txt: fix typos	2013-11-13 12:09:05 +09:00
w1
watchdog
wimax
x86	Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2013-11-12 10:48:30 +09:00
xtensa
zh_CN
.gitignore
00-INDEX	doc: fix a typo in Documentation/00-INDEX	2013-08-27 10:53:07 +02:00
applying-patches.txt
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
bcache.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes
circular-buffers.txt
clk.txt
coccinelle.txt
CodingStyle
cpu-hotplug.txt	MAINTAINERS: update Zwane Mwaikambo's e-mail address	2013-11-13 12:09:14 +09:00
cpu-load.txt
cputopology.txt	doc: Documentation/cputopology.txt fix typo	2013-09-04 12:59:47 +02:00
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt	cuse: add fix minor number to /dev/cuse	2013-10-01 16:44:54 +02:00
digsig.txt
DMA-API-HOWTO.txt
DMA-API.txt
DMA-attributes.txt
dma-buf-sharing.txt	dma-buf: Expose buffer size to userspace (v2)	2013-09-10 11:36:45 +05:30
DMA-ISA-LPC.txt
dmaengine.txt
dmatest.txt	dmatest: make module parameters writable	2013-08-22 22:57:32 -07:00
dontdiff
dynamic-debug-howto.txt
edac.txt
efi-stub.txt	EFI stub documentation updates	2013-09-25 12:34:32 +01:00
eisa.txt
email-clients.txt
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt	gcov: compile specific gcov implementation based on gcc version	2013-11-13 12:09:34 +09:00
gpio.txt
highuid.txt
HOWTO
hw_random.txt
hwspinlock.txt	doc: documentation/hwspinlock.txt fix typo	2013-08-27 10:46:02 +02:00
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt	drivers/char/hpet.c: allow user controlled mmap for user processes	2013-11-13 12:09:11 +09:00
kernel-per-CPU-kthreads.txt	kthread: Add pointer to vmstat-avoidance patch	2013-09-25 06:49:46 -07:00
kmemcheck.txt	Documentation/kmemcheck: update kmemcheck documentation	2013-08-27 10:47:05 +02:00
kmemleak.txt
kobject.txt
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
lockup-watchdogs.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt
memory-hotplug.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
mono.txt
mutex-design.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt	drivers: phy: add generic PHY framework	2013-09-27 17:35:41 -07:00
pi-futex.txt
pinctrl.txt	pinctrl: add documentation for pinctrl_get_group_pins()	2013-10-16 15:35:21 +02:00
pnp.txt
preempt-locking.txt
printk-formats.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
pwm.txt
ramoops.txt
rbtree.txt
remoteproc.txt
rfkill.txt
robust-futex-ABI.txt
robust-futexes.txt
rpmsg.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sysfs-rules.txt
sysrq.txt	sysrq: Allow magic SysRq key functions to be disabled through Kconfig	2013-10-16 13:01:44 -07:00
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt	vfio: fix documentation	2013-09-05 16:36:21 -06:00
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt	workqueue: Correct/Drop references to gcwq in Documentation	2013-08-21 10:32:09 -04:00
ww-mutex-design.txt
xz.txt
zorro.txt