[PATCH 0/7] V3 of the new lock algorithm

[Jens Gustedt <Jens.Gustedt@inria.fr>]

This patch series implements and applies the new internal lock
algorithm.

Patch 1 is the lock implementation itself. I hope this is fit for
1.19, now.

The patches 2-7 do some clean up and apply this lock algorithm to two
fields, where we had specialized lock implementations before:
condition variables and malloc.

In all of this I am still a bit uncomfortable with the double syscalls
to futex functions. We do that just because some older Linux versions
might not implement private futexes. I'd prefer if that could be
replaced by a read to a central variable instead of having a second
(conditional) syscall. Such a variable could be initialized during
thread-library initialization, I think.

Jens Gustedt (7):
  a new lock algorithm with lock value and congestion count in the same
    atomic int
  consistently use the LOCK an UNLOCK macros
  revise the definition of multiple basic locks in the code
  separate the fast parts of __lock and __unlock into a .h file that may
    be used by other TU
  use the new lock algorithm for malloc
  implement __unlock_requeue
  implement the local lock for condition variables with the new lock
    feature

 src/dirent/__dirent.h               |  2 +-
 src/exit/at_quick_exit.c            |  2 +-
 src/exit/atexit.c                   |  2 +-
 src/internal/__lock.h               | 29 ++++++++++++++++
 src/internal/libc.h                 |  3 ++
 src/internal/pthread_impl.h         | 10 ++++--
 src/locale/dcngettext.c             |  2 +-
 src/locale/locale_map.c             |  2 +-
 src/locale/setlocale.c              |  2 +-
 src/malloc/lite_malloc.c            |  2 +-
 src/malloc/malloc.c                 | 38 ++++++++-------------
 src/misc/syslog.c                   |  2 +-
 src/prng/random.c                   |  2 +-
 src/stdio/ofl.c                     |  2 +-
 src/thread/__lock.c                 | 66 +++++++++++++++++++++++++++++++++----
 src/thread/pthread_atfork.c         |  2 +-
 src/thread/pthread_cond_timedwait.c | 53 ++++++++++-------------------
 src/thread/pthread_create.c         |  6 ++--
 src/thread/pthread_detach.c         |  5 ++-
 src/thread/pthread_getschedparam.c  |  4 +--
 src/thread/pthread_kill.c           |  4 +--
 src/thread/pthread_setschedparam.c  |  4 +--
 src/thread/pthread_setschedprio.c   |  4 +--
 src/thread/sem_open.c               |  2 +-
 src/thread/synccall.c               |  2 +-
 src/time/__tz.c                     |  2 +-
 26 files changed, 156 insertions(+), 98 deletions(-)
 create mode 100644 src/internal/__lock.h

-- 
2.15.1