On Thu, Apr 21, 2022 at 6:40 PM Jan Kara <jack@xxxxxxx> wrote: > > On Wed 13-04-22 12:09:33, Amir Goldstein wrote: > > When an inode mark is created with flag FAN_MARK_EVICTABLE, it will not > > pin the marked inode to inode cache, so when inode is evicted from cache > > due to memory pressure, the mark will be lost. > > > > When an inode mark with flag FAN_MARK_EVICATBLE is updated without using > > this flag, the marked inode is pinned to inode cache. > > > > When an inode mark is updated with flag FAN_MARK_EVICTABLE but an > > existing mark already has the inode pinned, the mark update fails with > > error EEXIST. > > > > Evictable inode marks can be used to setup inode marks with ignored mask > > to suppress events from uninteresting files or directories in a lazy > > manner, upon receiving the first event, without having to iterate all > > the uninteresting files or directories before hand. > > > > The evictbale inode mark feature allows performing this lazy marks setup > > without exhausting the system memory with pinned inodes. > > > > This change does not enable the feature yet. > > > > Link: https://lore.kernel.org/linux-fsdevel/CAOQ4uxiRDpuS=2uA6+ZUM7yG9vVU-u212tkunBmSnP_u=mkv=Q@xxxxxxxxxxxxxx/ > > Signed-off-by: Amir Goldstein <amir73il@xxxxxxxxx> > > Just one nit below... > > > @@ -1097,6 +1099,18 @@ static int fanotify_mark_update_flags(struct fsnotify_mark *fsn_mark, > > *recalc = true; > > } > > > > + if (fsn_mark->connector->type != FSNOTIFY_OBJ_TYPE_INODE || > > + want_iref == !(fsn_mark->flags & FSNOTIFY_MARK_FLAG_NO_IREF)) > > + return 0; > > + > > + /* > > + * NO_IREF may be removed from a mark, but not added. > > + * When removed, fsnotify_recalc_mask() will take the inode ref. > > + */ > > + WARN_ON_ONCE(!want_iref); > > + fsn_mark->flags &= ~FSNOTIFY_MARK_FLAG_NO_IREF; > > + *recalc = true; > > + > > return 0; > > } > > Since we always return 0 from this function, we may as well just drop the > 'recalc' argument and return whether mask recalc is needed? > I agree, but in this case, I rather also return recalc from fanotify_mark_add_to_mask() and keep fsnotify_recalc_mask() in fanotify_add_mark() and it is now. Thanks, Amir.
