Amir Goldstein ad3ea16746 fanotify: limit number of event merge attempts ... commit b8cd0ee8cd upstream. Event merges are expensive when event queue size is large, so limit the linear search to 128 merge tests. [Stable backport notes] The following statement from upstream commit is irrelevant for backport: - -In combination with 128 size hash table, there is a potential to merge -with up to 16K events in the hashed queue. - [Stable backport notes] The problem is as old as fanotify and described in the linked cover letter "Performance improvement for fanotify merge". This backported patch fixes the performance issue at the cost of merging fewer potential events. Fixing the performance issue is more important than preserving the "event merge" behavior, which was not predictable in any way that applications could rely on. Link: https://lore.kernel.org/r/20210304104826.3993892-6-amir73il@gmail.com Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jan Kara <jack@suse.cz> Cc: <stable@vger.kernel.org> Link: https://lore.kernel.org/linux-fsdevel/20210202162010.305971-1-amir73il@gmail.com/ Link: https://lore.kernel.org/linux-fsdevel/20210915163334.GD6166@quack2.suse.cz/ Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2021-09-18 13:40:38 +02:00
..
dnotify	fsnotify: generalize handle_inode_event()	2020-12-30 11:54:18 +01:00
fanotify	fanotify: limit number of event merge attempts	2021-09-18 13:40:38 +02:00
inotify	inotify: convert to handle_inode_event() interface	2020-12-30 11:54:18 +01:00
fdinfo.c	fsnotify: Remove proc_fs.h include	2020-05-13 17:16:14 +02:00
fdinfo.h	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
fsnotify.c	fsnotify: fix events reported to watching parent and child	2020-12-30 11:54:18 +01:00
fsnotify.h	fsnotify: move declaration of fsnotify_mark_connector_cachep to fsnotify.h	2019-10-17 10:31:12 +02:00
group.c	fsnotify: add mutex destroy	2020-05-13 17:14:20 +02:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
mark.c	fsnotify: Add missing annotation for fsnotify_finish_user_wait() and for fsnotify_prepare_user_wait()	2020-04-15 11:44:43 +02:00
notification.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 18	2019-05-21 11:28:46 +02:00