[PATCH v2 0/5] Performance improvement for fanotify merge

[Amir Goldstein <amir73il@gmail.com>]

Jan,

Following is v2 for the fanotify_merge() performance improvements.

For more details on functional and performance tests please refer to
v1 cover letter [1].

This version is much simpler than v1 using standard hlist.
It was rebased and tested against 5.12-rc1 using LTP tests [2].

Thanks,
Amir.

Chanes since v1:
- Use hlist instead of multi notification lists
- Handling all hashing within fanotify backend
- Cram event key member together with event type
- Remove ifdefs and use constant queue hash bits
- Address other review comments on v1

[1] https://lore.kernel.org/linux-fsdevel/20210202162010.305971-1-amir73il@gmail.com/
[2] https://github.com/amir73il/ltp/commits/fanotify_merge

Amir Goldstein (5):
  fsnotify: allow fsnotify_{peek,remove}_first_event with empty queue
  fanotify: reduce event objectid to 29-bit hash
  fanotify: mix event info and pid into merge key hash
  fsnotify: use hash table for faster events merge
  fanotify: limit number of event merge attempts

 fs/notify/fanotify/fanotify.c        | 150 +++++++++++++++++++--------
 fs/notify/fanotify/fanotify.h        |  46 +++++++-
 fs/notify/fanotify/fanotify_user.c   |  65 ++++++++++--
 fs/notify/inotify/inotify_fsnotify.c |   9 +-
 fs/notify/inotify/inotify_user.c     |   7 +-
 fs/notify/notification.c             |  64 ++++++------
 include/linux/fsnotify_backend.h     |  23 ++--
 7 files changed, 263 insertions(+), 101 deletions(-)

-- 
2.30.0