[PATCH 0/5] ptrace-vs-PREEMPT_RT and freezer rewrite

[Peter Zijlstra]

Hi all,

Reviving the freezer rewrite that was languishing, reinvigorated by the
recent ptrace-vs-PREEMPT_RT trouble.

The first patch adds additional state to signal/ptrace stop states, this state
is then used to fix the PREEMPT_RT issue (patch #2) and allow the new freezer
to recover the special stop states (patch #5).

I'm not completely happy with the ptrace solution, but I think it solves all
the various issues I found. I still dislike wait_task_inactive() and now we
have a second copy of that :/

Please consider carefully..

---
 drivers/acpi/x86/s2idle.c         |  12 +-
 drivers/android/binder.c          |   4 +-
 drivers/media/pci/pt3/pt3.c       |   4 +-
 drivers/scsi/scsi_transport_spi.c |   7 +-
 fs/cifs/inode.c                   |   4 +-
 fs/cifs/transport.c               |   5 +-
 fs/coredump.c                     |   5 +-
 fs/nfs/file.c                     |   3 +-
 fs/nfs/inode.c                    |  12 +-
 fs/nfs/nfs3proc.c                 |   3 +-
 fs/nfs/nfs4proc.c                 |  14 +--
 fs/nfs/nfs4state.c                |   3 +-
 fs/nfs/pnfs.c                     |   4 +-
 fs/xfs/xfs_trans_ail.c            |   8 +-
 include/linux/completion.h        |   1 +
 include/linux/freezer.h           | 244 ++------------------------------------
 include/linux/sched.h             |  49 ++++----
 include/linux/sched/jobctl.h      |   8 ++
 include/linux/sched/signal.h      |  15 ++-
 include/linux/sunrpc/sched.h      |   7 +-
 include/linux/suspend.h           |   8 +-
 include/linux/umh.h               |   9 +-
 include/linux/wait.h              |  40 ++++++-
 init/do_mounts_initrd.c           |  10 +-
 kernel/cgroup/legacy_freezer.c    |  23 ++--
 kernel/exit.c                     |   4 +-
 kernel/fork.c                     |   5 +-
 kernel/freezer.c                  | 139 ++++++++++++++++------
 kernel/futex/waitwake.c           |   8 +-
 kernel/hung_task.c                |   4 +-
 kernel/power/hibernate.c          |  35 ++++--
 kernel/power/main.c               |  18 +--
 kernel/power/process.c            |  10 +-
 kernel/power/suspend.c            |  12 +-
 kernel/power/user.c               |  24 ++--
 kernel/ptrace.c                   | 185 +++++++++++++++++++++++------
 kernel/sched/completion.c         |   9 ++
 kernel/sched/core.c               |  24 ++--
 kernel/signal.c                   |  23 ++--
 kernel/time/hrtimer.c             |   4 +-
 kernel/umh.c                      |  18 ++-
 mm/khugepaged.c                   |   4 +-
 net/sunrpc/sched.c                |  12 +-
 net/unix/af_unix.c                |   8 +-
 44 files changed, 541 insertions(+), 507 deletions(-)