Allow EVFILT_VNODE events to work on every filesystem type, not just

UFS by:
- Making the pre and post hooks for the VOP functions work even when
DEBUG_VFS_LOCKS is not defined.
- Moving the KNOTE activations into the corresponding VOP hooks.
- Creating a MNTK_NOKNOTE flag for the mnt_kern_flag field of struct
mount that permits filesystems to disable the new behavior.
- Creating a default VOP_KQFILTER function: vfs_kqfilter()

My benchmarks have not revealed any performance degradation.

Reviewed by:	jeff, bde
Approved by:	rwatson, jmg (kqueue changes), grehan (mentor)

2 files changed, 0 insertions, 2 deletions

diff --git a/sys/gnu/ext2fs/ext2_vnops.c b/sys/gnu/ext2fs/ext2_vnops.c
index 81b08f6..56ead88 100644
--- a/sys/gnu/ext2fs/ext2_vnops.c
+++ b/sys/gnu/ext2fs/ext2_vnops.c
@@ -502,7 +502,6 @@ ext2_setattr(ap)
 			return (EROFS);
 		error = ext2_chmod(vp, (int)vap->va_mode, cred, td);
 	}
-	VN_KNOTE_UNLOCKED(vp, NOTE_ATTRIB);
 	return (error);
 }
 
diff --git a/sys/gnu/fs/ext2fs/ext2_vnops.c b/sys/gnu/fs/ext2fs/ext2_vnops.c
index 81b08f6..56ead88 100644
--- a/sys/gnu/fs/ext2fs/ext2_vnops.c
+++ b/sys/gnu/fs/ext2fs/ext2_vnops.c
@@ -502,7 +502,6 @@ ext2_setattr(ap)
 			return (EROFS);
 		error = ext2_chmod(vp, (int)vap->va_mode, cred, td);
 	}
-	VN_KNOTE_UNLOCKED(vp, NOTE_ATTRIB);
 	return (error);
 }