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| author | Mateusz Guzik <mjg@FreeBSD.org> | 2019-12-08 21:30:04 +0000 |
|---|---|---|
| committer | Mateusz Guzik <mjg@FreeBSD.org> | 2019-12-08 21:30:04 +0000 |
| commit | abd80ddb9474948fb291becc395d72b40927a32b (patch) | |
| tree | 5e32c99715a7ec2abcc89d4b8f76f07f0ad69bde /sys/fs/pseudofs | |
| parent | 791a24c7ea7d3ad41c703327d40e64d3ef6d02e2 (diff) | |
| download | src-abd80ddb9474948fb291becc395d72b40927a32b.tar.gz src-abd80ddb9474948fb291becc395d72b40927a32b.zip | |
vfs: introduce v_irflag and make v_type smaller
The current vnode layout is not smp-friendly by having frequently read data
avoidably sharing cachelines with very frequently modified fields. In
particular v_iflag inspected for VI_DOOMED can be found in the same line with
v_usecount. Instead make it available in the same cacheline as the v_op, v_data
and v_type which all get read all the time.
v_type is avoidably 4 bytes while the necessary data will easily fit in 1.
Shrinking it frees up 3 bytes, 2 of which get used here to introduce a new
flag field with a new value: VIRF_DOOMED.
Reviewed by: kib, jeff
Differential Revision: https://reviews.freebsd.org/D22715
Notes
Notes:
svn path=/head/; revision=355537
Diffstat (limited to 'sys/fs/pseudofs')
| -rw-r--r-- | sys/fs/pseudofs/pseudofs_vnops.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/sys/fs/pseudofs/pseudofs_vnops.c b/sys/fs/pseudofs/pseudofs_vnops.c index ce15547e44f5..0a3c9e967706 100644 --- a/sys/fs/pseudofs/pseudofs_vnops.c +++ b/sys/fs/pseudofs/pseudofs_vnops.c @@ -290,7 +290,7 @@ pfs_ioctl(struct vop_ioctl_args *va) vn = va->a_vp; vn_lock(vn, LK_SHARED | LK_RETRY); - if (vn->v_iflag & VI_DOOMED) { + if (VN_IS_DOOMED(vn)) { VOP_UNLOCK(vn, 0); return (EBADF); } @@ -512,7 +512,7 @@ pfs_lookup(struct vop_cachedlookup_args *va) vfs_rel(mp); if (error != 0) PFS_RETURN(ENOENT); - if (vn->v_iflag & VI_DOOMED) { + if (VN_IS_DOOMED(vn)) { vfs_unbusy(mp); PFS_RETURN(ENOENT); } @@ -581,13 +581,13 @@ pfs_lookup(struct vop_cachedlookup_args *va) if (cnp->cn_flags & ISDOTDOT) { vfs_unbusy(mp); vn_lock(vn, LK_EXCLUSIVE | LK_RETRY); - if (vn->v_iflag & VI_DOOMED) { + if (VN_IS_DOOMED(vn)) { vput(*vpp); *vpp = NULL; PFS_RETURN(ENOENT); } } - if (cnp->cn_flags & MAKEENTRY && !(vn->v_iflag & VI_DOOMED)) + if (cnp->cn_flags & MAKEENTRY && !VN_IS_DOOMED(vn)) cache_enter(vn, *vpp, cnp); PFS_RETURN (0); failed: |