On Sat, Mar 01 2008, Borislav Petkov wrote: > On Sat, Mar 01, 2008 at 10:55:18AM +0100, Jens Axboe wrote: > > On Sat, Mar 01 2008, Borislav Petkov wrote: > > > Hi Bart, > > > > > > here's the 1st draft of the pipeline removal series. As the diffstat below openly > > > states it, a lot of code got removed - even more than the cleanup series we did > > > earlier. There are several issues that we need to address concerning these > > > patches: > > > > > > 1. only compile-tested since i don't have the hardware, i.e. longer -mm brewing is > > > advisable the least. > > > > > > 2. I have left the tape->merge_stage buffer structure along with its > > > alloc/free functions intact for now, for simplicity. The next step would be > > > to go and carefully audit the code and then remove that last piece > > > too and use allocations on the stack instead. I guess we still expect > > > Jens's response on whether blk_{get,put}_request is the way to go here. > > > > > > Jens? > > > > Hm, I have not seen any questions regarding this directed my way :-) > > Please point me to the original question and I'll take a look at it. > > Hi Jens, > > sorry but maybe we weren't that explicit, here's a pointer to the > relevant thread: > http://www.mail-archive.com/linux-ide@xxxxxxxxxxxxxxx/msg15541.html. > It boils down to removing the statically allocated arrays of buffers > for pc and rq structs in ide-floppy and ide-tape, and using GFP_ATOMIC > stack memory instead. Bart's idea was to even go a step further and > even avoid allocation errors in out-of-mem situations by reusing > requests from the request queue but wasn't sure whether this'll fly > and wanted to run it by you... That sounds like asking for trouble, if you ask me (well you did :-) And being a very rarely exercised path (if at all, you should be very unlucky to NOT get a request even with GFP_ATOMIC), then it wont even get tested properly. So I'd say stick to GFP_ATOMIC, and just plug the device and retry if you get into allocation errors. -- Jens Axboe -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html