diff options
| author | peter <peter@FreeBSD.org> | 1998-04-18 06:26:16 +0000 |
|---|---|---|
| committer | peter <peter@FreeBSD.org> | 1998-04-18 06:26:16 +0000 |
| commit | bbf574dac9bac884a45d3fbd7f1b2ee9a74903ef (patch) | |
| tree | 2d269de2a79af5dc637172467135a4857e29c592 | |
| parent | 73c489feda99a875404deaa2730fd3978496c38f (diff) | |
| download | FreeBSD-src-bbf574dac9bac884a45d3fbd7f1b2ee9a74903ef.zip FreeBSD-src-bbf574dac9bac884a45d3fbd7f1b2ee9a74903ef.tar.gz | |
In vfs_msync(), test to see if the vnode being examined is "interesting"
(ie: it has a vm_object attached and is marked as OBJ_MIGHTBEDIRTY) before
attempting to lock it. This should reduce the cpu hit that is incurred
when doing a sync(2) and when the syncer process is doing the 30-second
writeback of dirty mmap() data to disk. Skip this speedup if we are
doing an unmount() to be sure to get everything - we can afford to
occasionally miss a msync while the system is running, but not at unmount.
I'm not sure about the VXLOCK and MNT_WAIT case, it seems a bit odd to skip
doing a page_clean at unmount time just because a vnode is VXLOCKed, but
that's what was being done before...
| -rw-r--r-- | sys/kern/vfs_export.c | 13 | ||||
| -rw-r--r-- | sys/kern/vfs_subr.c | 13 |
2 files changed, 20 insertions, 6 deletions
diff --git a/sys/kern/vfs_export.c b/sys/kern/vfs_export.c index 2950d85..8e6c9dc 100644 --- a/sys/kern/vfs_export.c +++ b/sys/kern/vfs_export.c @@ -36,7 +36,7 @@ * SUCH DAMAGE. * * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 - * $Id: vfs_subr.c,v 1.149 1998/04/15 18:37:49 tegge Exp $ + * $Id: vfs_subr.c,v 1.150 1998/04/16 03:31:26 peter Exp $ */ /* @@ -2404,6 +2404,7 @@ vfs_export_lookup(mp, nep, nam) void vfs_msync(struct mount *mp, int flags) { struct vnode *vp, *nvp; + struct vm_object *obj; int anyio, tries; tries = 5; @@ -2417,9 +2418,15 @@ loop: goto loop; } - if ((vp->v_flag & VXLOCK) || - (VOP_ISLOCKED(vp) && (flags != MNT_WAIT))) { + if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ continue; + + if (flags != MNT_WAIT) { + obj = vp->v_object; + if (obj == NULL || (obj->flags & OBJ_MIGHTBEDIRTY) == 0) + continue; + if (VOP_ISLOCKED(vp)) + continue; } simple_lock(&vp->v_interlock); diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c index 2950d85..8e6c9dc 100644 --- a/sys/kern/vfs_subr.c +++ b/sys/kern/vfs_subr.c @@ -36,7 +36,7 @@ * SUCH DAMAGE. * * @(#)vfs_subr.c 8.31 (Berkeley) 5/26/95 - * $Id: vfs_subr.c,v 1.149 1998/04/15 18:37:49 tegge Exp $ + * $Id: vfs_subr.c,v 1.150 1998/04/16 03:31:26 peter Exp $ */ /* @@ -2404,6 +2404,7 @@ vfs_export_lookup(mp, nep, nam) void vfs_msync(struct mount *mp, int flags) { struct vnode *vp, *nvp; + struct vm_object *obj; int anyio, tries; tries = 5; @@ -2417,9 +2418,15 @@ loop: goto loop; } - if ((vp->v_flag & VXLOCK) || - (VOP_ISLOCKED(vp) && (flags != MNT_WAIT))) { + if (vp->v_flag & VXLOCK) /* XXX: what if MNT_WAIT? */ continue; + + if (flags != MNT_WAIT) { + obj = vp->v_object; + if (obj == NULL || (obj->flags & OBJ_MIGHTBEDIRTY) == 0) + continue; + if (VOP_ISLOCKED(vp)) + continue; } simple_lock(&vp->v_interlock); |
