> -----Original Message----- > From: Michal Hocko [mailto:mhocko@xxxxxxx] > Sent: Thursday, July 25, 2013 3:57 AM > To: Dave Hansen > Cc: KY Srinivasan; Dave Hansen; gregkh@xxxxxxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; devel@xxxxxxxxxxxxxxxxxxxxxx; olaf@xxxxxxxxx; > apw@xxxxxxxxxxxxx; andi@xxxxxxxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx; linux- > mm@xxxxxxxxx; kamezawa.hiroyuki@xxxxxxxxx; hannes@xxxxxxxxxxx; > yinghan@xxxxxxxxxx; jasowang@xxxxxxxxxx; kay@xxxxxxxx > Subject: Re: [PATCH 1/1] Drivers: base: memory: Export symbols for onlining > memory blocks > > On Wed 24-07-13 14:02:32, Dave Hansen wrote: > > On 07/24/2013 12:45 PM, KY Srinivasan wrote: > > > All I am saying is that I see two classes of failures: (a) Our > > > inability to allocate memory to manage the memory that is being hot added > > > and (b) Our inability to bring the hot added memory online within a > reasonable > > > amount of time. I am not sure the cause for (b) and I was just speculating that > > > this could be memory related. What is interesting is that I have seen failure > related > > > to our inability to online the memory after having succeeded in hot adding the > > > memory. > > > > I think we should hold off on this patch and other like it until we've > > been sufficiently able to explain how (b) happens. > > Agreed. As promised, I have sent out the patches for (a) an implementation of an in-kernel API for onlining and a consumer for this API. While I don't know the exact reason why the user mode code is delayed (under some low memory conditions), what is the harm in having a mechanism to online memory that has been hot added without involving user space code. Based on Michal's feedback, the onlininig API hides all of the internal details and presents a generic interface. Regards, K. Y _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
