Subject: Re: File system suspension -- new API
To: Pavel Cahyna <email@example.com>
From: Juergen Hannken-Illjes <firstname.lastname@example.org>
Date: 12/31/2006 12:13:21
On Sun, Dec 31, 2006 at 12:04:38PM +0100, Pavel Cahyna wrote:
> On Sun, Dec 31, 2006 at 11:46:27AM +0100, Juergen Hannken-Illjes wrote:
> > On Sun, Dec 31, 2006 at 10:34:03AM +0000, Pavel Cahyna wrote:
> > > Why should it ignore lock while suspending instead of taking them
> > > normally?
> > As we cannot add fstrans_start() to xxx_lock() not ignoring locks will
> > quickly deadlock.
> Why can't you add fstrans_start(..., fstrans_shared) to ufs_lock before
> the call to lockmgr()?
- ufs_lock() is called with vp->v_interlock held. As fstrans_start() is
allowed to sleep it cannot be called here.
- There are plans to completely remove VOP_LOCK() and therefore new
subsystems should not rely on it.
Juergen Hannken-Illjes - email@example.com - TU Braunschweig (Germany)