I've got another question about powerpc reconfiguration. I was looking at the dlpar_configure_connector() function in dlpar.c. I see that the function has the ability to process multiple nodes with additional sibling and child nodes. It appears to link them into a detached tree structure, and the function returns a pointer to the first node. All of the callers of that function then call dlpar_attach_node(), which calls of_attach_node(). However, of_attach_node() only handles a single node. It doesn't handle siblings or children. Is this a bug? Does the configure connector ever actually receive more than one node at once? g. On Fri, Jun 27, 2014 at 8:41 AM, Nathan Fontenot <nfont@xxxxxxxxxxxxxx> wrote: > On 06/27/2014 07:41 AM, Grant Likely wrote: >> On Thu, 26 Jun 2014 15:01:49 -0500, Nathan Fontenot <nfont@xxxxxxxxxxxxxx> wrote: >>> On 06/25/2014 03:24 PM, Grant Likely wrote: >>>> On Tue, 24 Jun 2014 15:10:55 -0500, Nathan Fontenot <nfont@xxxxxxxxxxxxxx> wrote: >>>>>>> heh! I have often thought about adding reference counting to device tree >>>>>>> properties. >>>>>> >>>>>> You horrible, horrible man. >>>>> >>>>> Yes. I are evil :) >>>>> >>>>> After looking again the work needed to add reference counts to properties >>>>> would be huge. The few properties I am concerned with are specific to powerpc >>>>> so perhaps just adding an arch specific lock around updating those >>>>> properties would work. >>>> >>>> Which code/properties? I'd like to have a look myself. >>> >>> /ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory >>> >>> The property is updated in >>> arch/powerpc/platforms/pseries/hotplug-memory.c:pseries_update_drconf_memory() >> >> Specifically, what do you need for the locking? Are you wanting to hold >> off additional changes while that function is executing? Pantelis is >> adding a mutex for device tree writers. Holding that mutex would prevent >> any changes from happening in the tree without affecting readers. Would >> that be sufficient? > > That would work. > > -Nathan > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
