linux-brain/drivers
Andrei Vagin d1be35cb6f proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps
seq_put_decimal_ull_w(m, str, val, width) prints a decimal number with a
specified minimal field width.

It is equivalent of seq_printf(m, "%s%*d", str, width, val), but it
works much faster.

== test_smaps.py
  num = 0
  with open("/proc/1/smaps") as f:
          for x in xrange(10000):
                  data = f.read()
                  f.seek(0, 0)
==

== Before patch ==
  $ time python test_smaps.py
  real    0m4.593s
  user    0m0.398s
  sys     0m4.158s

== After patch ==
  $ time python test_smaps.py
  real    0m3.828s
  user    0m0.413s
  sys     0m3.408s

$ perf -g record python test_smaps.py
== Before patch ==
-   79.01%     3.36%  python   [kernel.kallsyms]    [k] show_smap.isra.33
   - 75.65% show_smap.isra.33
      + 48.85% seq_printf
      + 15.75% __walk_page_range
      + 9.70% show_map_vma.isra.23
        0.61% seq_puts

== After patch ==
-   75.51%     4.62%  python   [kernel.kallsyms]    [k] show_smap.isra.33
   - 70.88% show_smap.isra.33
      + 24.82% seq_put_decimal_ull_w
      + 19.78% __walk_page_range
      + 12.74% seq_printf
      + 11.08% show_map_vma.isra.23
      + 1.68% seq_puts

[akpm@linux-foundation.org: fix drivers/of/unittest.c build]
Link: http://lkml.kernel.org/r/20180212074931.7227-1-avagin@openvz.org
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-11 10:28:33 -07:00
..
accessibility
acpi libnvdimm for 4.17 2018-04-10 10:25:57 -07:00
amba
android
ata Merge branch 'for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata 2018-04-03 17:42:25 -07:00
atm Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-01 19:49:34 -04:00
auxdisplay
base mm: check __highest_present_section_nr directly in memory_dev_init() 2018-04-11 10:28:31 -07:00
bcma
block Merge branch 'akpm' (patches from Andrew) 2018-04-06 14:19:26 -07:00
bluetooth Bluetooth: Set HCI_QUIRK_SIMULTANEOUS_DISCOVERY for BTUSB_QCA_ROME 2018-04-01 21:43:02 +03:00
bus pci-v4.17-changes 2018-04-06 18:31:06 -07:00
cdrom
char RTC for 4.17 2018-04-10 10:22:27 -07:00
clk ARM: SoC driver updates for 4.17 2018-04-05 21:29:35 -07:00
clocksource ARM: SoC platform updates for 4.17 2018-04-05 21:21:08 -07:00
connector
cpufreq ARM: SoC driver updates for 4.17 2018-04-05 21:29:35 -07:00
cpuidle cpuidle: poll_state: Avoid invoking local_clock() too often 2018-03-29 13:06:08 +02:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2018-04-04 17:11:08 -07:00
dax libnvdimm for 4.17 2018-04-10 10:25:57 -07:00
dca
devfreq
dio
dma dmaengine: stm32-dmamux: fix a potential buffer overflow 2018-03-22 10:51:35 +05:30
dma-buf
edac * Add NVDIMM support to EDAC (Tony Luck) 2018-04-05 14:21:13 -07:00
eisa
extcon Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
firewire
firmware MIPS changes for 4.17 2018-04-10 11:39:22 -07:00
fmc treewide: Fix typos in printk 2018-03-27 09:51:22 +02:00
fpga PCI: Add Altera vendor ID 2018-03-19 14:18:22 -05:00
fsi
gpio DeviceTree updates for 4.17: 2018-04-05 21:03:42 -07:00
gpu treewide: fix up files incorrectly marked executable 2018-04-07 13:31:23 -07:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid 2018-04-05 11:53:34 -07:00
hsi
hv ARM: 2018-04-09 11:42:31 -07:00
hwmon hwmon updates for v4.17 2018-04-09 19:59:54 -07:00
hwspinlock
hwtracing Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
i2c Merge branch 'i2c/for-4.17' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux 2018-04-07 12:36:18 -07:00
ide for-4.17/block-20180402 2018-04-05 14:27:02 -07:00
idle
iio This is the bulk of GPIO changes for the v4.17 kernel cycle: 2018-04-05 09:51:41 -07:00
infiniband Merge candidates for 4.17 merge window 2018-04-06 17:35:43 -07:00
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2018-04-05 13:21:57 -07:00
iommu headers: untangle kmemleak.h from mm.h 2018-04-05 21:36:27 -07:00
ipack
irqchip Staging/IIO patches for 4.17-rc1 2018-04-04 18:56:27 -07:00
isdn Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2018-04-03 14:04:18 -07:00
leds leds: Fix wrong dmi_match on PC Engines APU LEDs 2018-03-20 20:28:00 +01:00
lightnvm lightnvm: pblk: remove some unnecessary NULL checks 2018-03-29 17:29:09 -06:00
macintosh powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
mailbox mailbox: Add support for Hi3660 mailbox 2018-03-20 11:15:54 +08:00
mcb mcb: Add Altera PCI ID to mcb-pci 2018-03-19 14:20:24 -05:00
md libnvdimm for 4.17 2018-04-10 10:25:57 -07:00
media media updates for v4.17-rc1 2018-04-10 10:10:30 -07:00
memory
memstick
message treewide: Align function definition open/close braces 2018-03-26 11:13:09 +02:00
mfd
misc powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
mmc for-4.17/block-20180402 2018-04-05 14:27:02 -07:00
mtd MTD changes: 2018-04-06 12:15:41 -07:00
mux
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-09 17:04:10 -07:00
nfc
ntb
nubus
nvdimm libnvdimm for 4.17 2018-04-10 10:25:57 -07:00
nvme for-4.17/block-20180402 2018-04-05 14:27:02 -07:00
nvmem Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
of proc: add seq_put_decimal_ull_width to speed up /proc/pid/smaps 2018-04-11 10:28:33 -07:00
opp
oprofile oprofilefs: don't oops on allocation failure 2018-03-29 15:07:48 -04:00
parisc parisc/pci: Switch LBA PCI bus from Hard Fail to Soft Fail mode 2018-03-27 18:52:22 +02:00
parport Char/Misc patches for 4.17-rc1 2018-04-04 20:07:20 -07:00
pci powerpc updates for 4.17 2018-04-07 12:08:19 -07:00
pcmcia Merge branch 'for-linus-sa1100' of git://git.armlinux.org.uk/~rmk/linux-arm 2018-04-09 09:26:36 -07:00
perf ARM: SoC driver updates for 4.17 2018-04-05 21:29:35 -07:00
phy ARM: SoC platform updates for 4.17 2018-04-05 21:21:08 -07:00
pinctrl This is the bulk of GPIO changes for the v4.17 kernel cycle: 2018-04-05 09:51:41 -07:00
platform Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2018-04-05 11:56:35 -07:00
pnp
power ARM: SoC platform updates for 4.17 2018-04-05 21:21:08 -07:00
powercap
pps
ps3
ptp
pwm ARM: SoC platform updates for 4.17 2018-04-05 21:21:08 -07:00
rapidio
ras
regulator Merge remote-tracking branches 'regulator/topic/88pg86x', 'regulator/topic/dt', 'regulator/topic/formatting' and 'regulator/topic/gpio' into regulator-next 2018-03-28 10:33:53 +08:00
remoteproc
reset Merge branch 'reset/lookup' into reset/next 2018-03-27 11:03:43 +02:00
rpmsg
rtc RTC for 4.17 2018-04-10 10:22:27 -07:00
s390 libnvdimm for 4.17 2018-04-10 10:25:57 -07:00
sbus sparc64: Properly range check DAX completion index 2018-04-01 20:07:00 -04:00
scsi SCSI for-linus on 20180404 2018-04-05 15:05:53 -07:00
sfi
sh
siox
slimbus
sn
soc ARM: SoC driver updates for 4.17 2018-04-05 21:29:35 -07:00
soundwire
spi spi: SPI updates for v4.17 2018-04-03 12:06:21 -07:00
spmi
ssb
staging media updates for v4.17-rc1 2018-04-10 10:10:30 -07:00
target for-4.17/block-20180402 2018-04-05 14:27:02 -07:00
tc
tee
thermal
thunderbolt
tty Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-04-09 09:04:10 -07:00
uio
usb Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2018-04-07 11:11:41 -07:00
uwb
vfio VFIO updates for v4.17-rc1 2018-04-06 19:44:27 -07:00
vhost Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-04-09 17:04:10 -07:00
video fbdev changes for v4.17: 2018-04-10 10:20:00 -07:00
virt
virtio headers: untangle kmemleak.h from mm.h 2018-04-05 21:36:27 -07:00
visorbus
vlynq
vme
w1
watchdog This is the bulk of GPIO changes for the v4.17 kernel cycle: 2018-04-05 09:51:41 -07:00
xen x86/dma: Remove dma_alloc_coherent_mask() 2018-03-20 10:01:56 +01:00
zorro
Kconfig hwtracing: Add HW tracing support menu 2018-03-29 13:38:10 +03:00
Makefile