On Fri, Oct 19, 2012 at 7:16 AM, Rafael J. Wysocki <r...@sisk.pl> wrote: > > Well, the question is how many runtime resume callbacks actually allocate > memory. If they are not too many, we can just flag all of them. Otherwise,
At least, almost all pci devices driver in some platform(acpi) and all usb devices driver allocate memory with GFP_KERNEL which is done in subsystem, see below: http://marc.info/?l=linux-kernel&m=135044522501229&w=2 I also found that many usb interface drivers(usblp, uvc, gspca, most of dvb-usb-v2 media drivers, cpia2, az6007, ....) will do it too. It is not good to convert all these GFP_KERNEL into GFP_NOIO because the function doing that will be called in many other contexts. That is just what I have found. Unfortunately, this allocation can only be found by human being now, maybe there are many not found since any function in the resume path(call tree) may allocate memory with GFP_KERNEL. In fact, memalloc_noio() can convert some of current static GFP_NOIO allocation into GFP_KERNEL in other contexts, at least almost all GFP_NOIO in USB subsystem can be converted into GFP_KERNEL after applying the approach and make allocation with GFP_IO only happen in runtime resume/bus reset/block I/O transfer contexts generally. > adding a flag may be a better approach. I'm not sure ATM. OK, I will prepare -v2 with the flag approach for review. Thanks, -- Ming Lei -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/