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linux/fs/proc
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Andrei Vagin 0e3dc01914 procfs: add seq_put_hex_ll to speed up /proc/pid/maps 
seq_put_hex_ll() prints a number in hexadecimal notation and works
faster than seq_printf().

== test.py
  num = 0
  with open("/proc/1/maps") as f:
          while num < 10000 :
                  data = f.read()
                  f.seek(0, 0)
                 num = num + 1
==

== Before patch ==
  $  time python test.py

  real	0m1.561s
  user	0m0.257s
  sys	0m1.302s

== After patch ==
  $ time python test.py

  real	0m0.986s
  user	0m0.279s
  sys	0m0.707s

$ perf -g record python test.py:

== Before patch ==
-   67.42%     2.82%  python   [kernel.kallsyms] [k] show_map_vma.isra.22
   - 64.60% show_map_vma.isra.22
      - 44.98% seq_printf
         - seq_vprintf
            - vsnprintf
               + 14.85% number
               + 12.22% format_decode
                 5.56% memcpy_erms
      + 15.06% seq_path
      + 4.42% seq_pad
   + 2.45% __GI___libc_read

== After patch ==
-   47.35%     3.38%  python   [kernel.kallsyms] [k] show_map_vma.isra.23
   - 43.97% show_map_vma.isra.23
      + 20.84% seq_path
      - 15.73% show_vma_header_prefix
           10.55% seq_put_hex_ll
         + 2.65% seq_put_decimal_ull
           0.95% seq_putc
      + 6.96% seq_pad
   + 2.94% __GI___libc_read

[avagin@openvz.org: use unsigned int instead of int where it is suitable]
  Link: http://lkml.kernel.org/r/20180214025619.4005-1-avagin@openvz.org
[avagin@openvz.org: v2]
  Link: http://lkml.kernel.org/r/20180117082050.25406-1-avagin@openvz.org
Link: http://lkml.kernel.org/r/20180112185812.7710-1-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 10:28:32 -07:00
..
array.c fs/proc/array.c: delete children_seq_release() 2018-02-06 18:32:43 -08:00
base.c procfs: remove CONFIG_HARDWALL dependency 2018-03-16 10:56:08 +01:00
cmdline.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
consoles.c fs/proc/consoles.c: use seq_putc() in show_console_dev() 2018-02-06 18:32:44 -08:00
cpuinfo.c x86 / CPU: Always show current CPU frequency in /proc/cpuinfo 2017-11-15 19:46:50 +01:00
devices.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fd.c proc: use %u for pid printing and slightly less stack 2018-02-06 18:32:43 -08:00
fd.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
generic.c proc: rearrange args 2018-02-06 18:32:43 -08:00
inode.c proc: spread likely/unlikely a bit 2018-02-06 18:32:43 -08:00
internal.h proc: rearrange args 2018-02-06 18:32:43 -08:00
interrupts.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Kconfig
kcore.c vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page 2018-02-13 09:15:58 +01:00
kmsg.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
loadavg.c pid: replace pid bitmap implementation with IDR API 2017-11-17 16:10:03 -08:00
Makefile proc: : uninline name_to_int() 2017-11-17 16:10:00 -08:00
meminfo.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
namespaces.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nommu.c Replace <asm/uaccess.h> with <linux/uaccess.h> globally 2016-12-24 11:46:01 -08:00
page.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
proc_net.c proc: rearrange args 2018-02-06 18:32:43 -08:00
proc_sysctl.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
proc_tty.c TTY/Serial patches for 4.15-rc1 2017-11-13 21:05:31 -08:00
root.c Rename superblock flags (MS_xyz -> SB_xyz) 2017-11-27 13:05:09 -08:00
self.c fs/proc: use __ro_after_init 2018-02-06 18:32:43 -08:00
softirqs.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
stat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
task_mmu.c procfs: add seq_put_hex_ll to speed up /proc/pid/maps 2018-04-11 10:28:32 -07:00
task_nommu.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
thread_self.c fs/proc: use __ro_after_init 2018-02-06 18:32:43 -08:00
uptime.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
util.c proc: use do-while in name_to_int() 2017-11-17 16:10:00 -08:00
version.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vmcore.c fs/proc/vmcore.c: simpler /proc/vmcore cleanup 2018-02-06 18:32:43 -08:00