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Date:   Thu, 14 Jul 2022 09:02:27 -0700
From:   Ira Weiny <ira.weiny@intel.com>
To:     Dan Williams <dan.j.williams@intel.com>
CC:     Matthew Wilcox <willy@infradead.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
        Alison Schofield <alison.schofield@intel.com>,
        Vishal Verma <vishal.l.verma@intel.com>,
        <linux-kernel@vger.kernel.org>, <linux-cxl@vger.kernel.org>,
        <linux-pci@vger.kernel.org>, <linux-fsdevel@vger.kernel.org>
Subject: Re: [RFC PATCH 1/3] xarray: Introduce devm_xa_init()
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On Thu, Jul 14, 2022 at 08:44:00AM -0700, Dan Williams wrote:
> Ira Weiny wrote:
> > On Fri, Jul 08, 2022 at 03:53:50PM +0100, Matthew Wilcox wrote:
> > > On Tue, Jul 05, 2022 at 04:21:57PM -0700, ira.weiny@intel.com wrote:
> > > > The main issue I see with this is defining devm_xa_init() in device.h.
> > > > This makes sense because a device is required to use the call.  However,
> > > > I'm worried about if users will find the call there vs including it in
> > > > xarray.h?
> > > 
> > > Honestly, I don't want users to find it.  This only makes sense if you're
> > > already bought in to the devm cult.  I worry people will think that
> > > they don't need to do anything else; that everything will be magically
> > > freed for them, and we'll leak the objects pointed to from the xarray.
> > > I don't even like having xa_destroy() in the API, because of exactly this.
> > > 
> > 
> > Fair enough.  Are you ok with the concept though?
> 
> I came here to same the same thing as Matthew. devm_xa_init() does not
> lessen review burden like other devm helpers. A reviewer still needs to
> go verfy that the patch that uses this makes sure to free all objects in
> the xarray before it gets destroyed.
> 
> If there still needs to be an open-coded "empty the xarray" step, then
> that can just do the xa_destroy() there. So for me, no, the concept of
> this just not quite jive.

Ok I'll drop it.
Ira