mbox

[v3,0/4] Add CLOCK_MONOTONIC support for PI mutexes

Message ID 20210906204740.3988273-1-adhemerval.zanella@linaro.org
Headers

Message

Adhemerval Zanella Netto Sept. 6, 2021, 8:47 p.m. UTC 
  It adds support for CLOCK_MONOTONIC for PI mutexes by using the new
Linux v5.14 FUTEX_LOCK_PI2 operation.  Similar to current approach,
pthread_mutex_clocklock might return EINVAL if the underlying kernel
has no support for the futex operation.

Changes since v2:

  * Renamed xpthread_mutex_pi_support_monotonic to
    support_mutex_pi_monotonic.

Changes since v1:
  
  * Refactor futex_lock_pi64 and avoid adding futex_lock_pi2.  The
    FUTEX_LOCK_PI2 logic is done at only one place, so the code change
    on pthread routines are minimal.  Also, FUTEX_LOCK_PI2 is only
    used if it is really required, i.e, when a timeout against
    CLOCK_MONOTONIC is used.
  * Do not remove nptl/tst-mutexpi10.c, but instead adjust it to new
    FUTEX_LOCK_PI2 support.
  * Add pthread_mutex_pi_support_monotonic() to check if monotonic
    clock with PI mutexes are supported and use on test to check for
    the expected result.

Adhemerval Zanella (3):
  nptl: Use FUTEX_LOCK_PI2 when available
  support: Add support_mutex_pi_monotonic
  nptl: Add CLOCK_MONOTONIC support for PI mutexes

Kurt Kanzenbach (1):
  Linux: Add FUTEX_LOCK_PI2

 nptl/futex-internal.c                     | 63 +++++++++++++++++++++++
 nptl/pthread_mutex_lock.c                 |  3 +-
 nptl/pthread_mutex_timedlock.c            | 10 +---
 nptl/tst-mutexpi10.c                      | 42 +++++++++------
 support/Makefile                          |  1 +
 support/support_mutex_pi_monotonic.c      | 33 ++++++++++++
 support/xthread.h                         |  4 ++
 sysdeps/nptl/futex-internal.h             | 58 ++-------------------
 sysdeps/nptl/lowlevellock-futex.h         |  1 +
 sysdeps/pthread/tst-mutex5.c              | 23 ++++++---
 sysdeps/pthread/tst-mutex9.c              | 20 ++++---
 sysdeps/unix/sysv/linux/kernel-features.h |  8 +++
 12 files changed, 172 insertions(+), 94 deletions(-)
 create mode 100644 support/support_mutex_pi_monotonic.c