[LinuxPPS] [PATCHv6 00/16] pps: several fixes and improvements

Alexander Gordeev lasaine at lvk.cs.msu.su
Fri Dec 17 20:54:24 CET 2010


This patchset contains several changes that improve an overall
design/performance of PPS subsystem. I'd like these patches to be
merged mainline if no one objects.

Patches 1-3 are bugfixes.
Patches 4-11 are other improvements to PPS subsystem.
Patches 12-14 add kernel consumer support.
Patch 15 adds parallel port PPS client.
Patch 16 adds parallel port PPS generator.

You can find description for my previous patchset (it describes patches
12-16 in more detail) here: http://lkml.org/lkml/2010/2/24/189

This patchset is tested against the vanilla 2.6.37-rc6 kernel. But we are
actually using it on 2.6.33.7-rt29 rt-preempt kernel most of the time.
Those who are interested in other versions of the patchset can find
them in my git repository:
git://github.com/ago/linux-2.6.git

There is one problem however: kernel consumer works bad (if enabled)
when CONFIG_NO_HZ is enabled. The reason for this is commit
a092ff0f90cae22b2ac8028ecd2c6f6c1a9e4601. Without it hardpps() is able
to sync to 1us precision in about 10 seconds. With CONFIG_NO_HZ it is
not syncing at all. This only affects patches 12-14, others are ok.

Changelog
v5 -> v6:
 * drop patch that fixes a race condition in tty code because it's already
   fixed in 2.6.37-rc2
 * fix getnstime_raw_and_real() comments (thanks Thomas Gleixner for the note)

Alexander Gordeev (16):
  pps: trivial fixes
  pps: declare variables where they are used in switch
  pps: fix race in PPS_FETCH handler
  pps: unify timestamp gathering
  pps: access pps device by direct pointer
  pps: convert printk/pr_* to dev_*
  pps: move idr stuff to pps.c
  pps: do not disable interrupts for idr operations
  pps: use BUG_ON for kernel API safety checks
  pps: simplify conditions a bit
  pps: timestamp is always passed to dcd_change()
  ntp: add hardpps implementation
  pps: capture MONOTONIC_RAW timestamps as well
  pps: add kernel consumer support
  pps: add parallel port PPS client
  pps: add parallel port PPS signal generator

 Documentation/ioctl/ioctl-number.txt     |    2 +-
 Documentation/pps/pps.txt                |   46 ++++
 Documentation/serial/tty.txt             |    2 +-
 drivers/pps/Kconfig                      |   10 +
 drivers/pps/Makefile                     |    2 +-
 drivers/pps/clients/Kconfig              |    7 +
 drivers/pps/clients/Makefile             |    1 +
 drivers/pps/clients/pps-ktimer.c         |   44 ++--
 drivers/pps/clients/pps-ldisc.c          |   59 ++--
 drivers/pps/clients/pps_parport.c        |  247 +++++++++++++++++
 drivers/pps/generators/Kconfig           |   17 ++
 drivers/pps/generators/Makefile          |    9 +
 drivers/pps/generators/pps_gen_parport.c |  275 +++++++++++++++++++
 drivers/pps/kapi.c                       |  221 +++++-----------
 drivers/pps/pps.c                        |  177 ++++++++++---
 include/linux/pps.h                      |    7 +
 include/linux/pps_kernel.h               |   54 +++-
 include/linux/serial_core.h              |    5 +-
 include/linux/time.h                     |    2 +
 include/linux/timex.h                    |    1 +
 include/linux/tty_ldisc.h                |    7 +-
 kernel/time/ntp.c                        |  425 ++++++++++++++++++++++++++++-
 kernel/time/timekeeping.c                |   39 +++
 23 files changed, 1374 insertions(+), 285 deletions(-)
 create mode 100644 drivers/pps/clients/pps_parport.c
 create mode 100644 drivers/pps/generators/Kconfig
 create mode 100644 drivers/pps/generators/Makefile
 create mode 100644 drivers/pps/generators/pps_gen_parport.c

-- 
1.7.2.3




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