[PATCH 00/21] binder: convert alloc->mutex to spinlock

[Carlos Llamas <cmllamas@google.com>]

This series refactors the binder buffer allocation space to be able to
convert the alloc->mutex into a spinlock. Doing so decreases the latency
of binder transactions seen under worst-case scenarios.

I attempted to organize and improve readability of things that were
touched during this process. I also include a couple of fixes (unrelated
to the lock convertion) for issues I found along the way.

Regards,
Carlos Llamas

Cc: Todd Kjos <tkjos@google.com>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: John Stultz <jstultz@google.com>
Cc: Suren Baghdasaryan <surenb@google.com> 
Cc: Tim Murray <timmurray@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Carlos Llamas (21):
  binder: use EPOLLERR from eventpoll.h
  binder: fix use-after-free in shinker's callback
  binder: fix race between mmput() and do_exit()
  binder: fix async space check for 0-sized buffers
  binder: fix trivial typo of binder_free_buf_locked()
  binder: fix comment on binder_alloc_new_buf() return value
  binder: remove extern from function prototypes
  binder: keep vma addresses type as unsigned long
  binder: split up binder_update_page_range()
  binder: do unlocked work in binder_alloc_new_buf()
  binder: remove pid param in binder_alloc_new_buf()
  binder: separate the no-space debugging logic
  binder: relocate low space calculation
  binder: do not add pages to LRU in release path
  binder: relocate binder_alloc_clear_buf()
  binder: refactor page range allocation
  binder: malloc new_buffer outside of locks
  binder: initialize lru pages in mmap callback
  binder: perform page allocation outside of locks
  binder: reverse locking order in shrinker callback
  binder: switch alloc->mutex to spinlock_t

 drivers/android/binder.c                |  25 +-
 drivers/android/binder_alloc.c          | 746 ++++++++++++------------
 drivers/android/binder_alloc.h          |  57 +-
 drivers/android/binder_alloc_selftest.c |   8 +-
 drivers/android/binder_trace.h          |   2 +-
 5 files changed, 428 insertions(+), 410 deletions(-)


base-commit: 21e80f3841c01aeaf32d7aee7bbc87b3db1aa0c6
-- 
2.42.0.869.gea05f2083d-goog