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Date: Fri, 5 Apr 2024 12:21:52 -0700
From: Ira Weiny <ira.weiny@intel.com>
To: Dave Jiang <dave.jiang@intel.com>, Ira Weiny <ira.weiny@intel.com>, Fan Ni
	<fan.ni@samsung.com>, Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	"Navneet Singh" <navneet.singh@intel.com>
CC: Dan Williams <dan.j.williams@intel.com>, Davidlohr Bueso
	<dave@stgolabs.net>, Alison Schofield <alison.schofield@intel.com>, "Vishal
 Verma" <vishal.l.verma@intel.com>, <linux-btrfs@vger.kernel.org>,
	<linux-cxl@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 05/26] cxl/core: Simplify cxl_dpa_set_mode()
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Dave Jiang wrote:
> 
> 
> On 3/24/24 4:18 PM, Ira Weiny wrote:
> > cxl_dpa_set_mode() checks the mode for validity two times, once outside
> > of the DPA RW semaphore and again within.  The function is not in a
> > critical path.  Prior to Dynamic Capacity the extra check was not much
> > of an issue.  The addition of DC modes increases the complexity of
> > the check.
> > 
> > Simplify the mode check before adding the more complex DC modes.
> 
> I would augment this by saying simplify "by using scope-based resource menagement".

However, using the guard cleanup is not really the simplification here.  It is
more about checking the mode a single time.

That said I will change this to:

Simplify the mode check and convert to use of a cleanup guard.

Ira