From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [RFC PATCH] of: make MAX_RESERVED_REGIONS configurable Date: Sat, 24 Nov 2018 14:56:13 -0600 Message-ID: References: <1542787873-8429-1-git-send-email-miles.chen@mediatek.com> <1542855088.15789.6.camel@mtkswgap22> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: <1542855088.15789.6.camel@mtkswgap22> Sender: linux-kernel-owner@vger.kernel.org To: Miles Chen Cc: Frank Rowand , devicetree@vger.kernel.org, "linux-kernel@vger.kernel.org" , "moderated list:ARM/FREESCALE IMX / MXC ARM ARCHITECTURE" , linux-mediatek@lists.infradead.org, wsd_upstream@mediatek.com List-Id: devicetree@vger.kernel.org On Wed, Nov 21, 2018 at 8:51 PM Miles Chen wrote: > > On Wed, 2018-11-21 at 10:39 -0600, Rob Herring wrote: > > On Wed, Nov 21, 2018 at 2:11 AM wrote: > > > > > > From: Miles Chen > > > > > > When we use more than 32 entries in /resered-memory, > > > there will be an error message: "not enough space all defined regions.". > > > We can increase MAX_RESERVED_REGIONS to fix this. > > > > > > commit 22f8cc6e3373 ("drivers: of: increase MAX_RESERVED_REGIONS to 32") > > > increased MAX_RESERVED_REGIONS to 32 but I'm not sure if increasing > > > MAX_RESERVED_REGIONS to 64 is suitable for everyone. > > > > > > In this RFC patch, CONFIG_MAX_OF_RESERVED_REGIONS is added and used as > > > MAX_RESERVED_REGIONS. Add a sanity test to make sure that > > > MAX_RESERVED_REGIONS is less than INIT_MEMBLOCK_REGIONS. > > > Users can configure CONFIG_MAX_OF_RESERVED_REGIONS according to their > > > need. > > > > I don't want a kconfig option for this. I think it should be dynamic instead. > > > > The current flow is like this: > > > > for each reserved node: > > - call memblock_reserve > > - Add info to reserved_mem array > > > > I think we should change it to: > > > > for each reserved node: > > - call memblock_reserve > > - count number of nodes > > > > Alloc array using memblock_alloc > > > > for each reserved node: > > - Add info to reserved_mem array > > > > thanks for your comment. > > I reviewed the flow and it might be easier to count the > nodes and setup array first: > > for each reserved node: > - count number of nodes > > Alloc array using memblock_alloc > > > for each reserved node: > - call memblock_reserve The order here is wrong. It is important that you reserve the memory blocks before doing any allocations. > - Add info to reserved_mem array > > What do you think? > > > Rob > >