On 05/16/2012 03:35 AM, Peng Tao wrote: > On Wed, May 16, 2012 at 12:23 AM, Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote: >> On 05/15/2012 07:08 PM, Christoph Hellwig wrote: >> >>> On Tue, May 15, 2012 at 11:38:22PM +0800, Peng Tao wrote: >>>> We bypass generic_file_aio_write() but would want to call block plug. >>> >>> We in this case is the pnfs block driver at most. Thus these should >>> be pnfs block code. > Agreed. Just that for buffer IO case all call into block plug, so I > thought it might be OK in DIO case as well... Anyway. I will make it > block specific and call it LD()->dio_begin and LD()->dio_end. I am > cooking some dio alignment patches for block layout driver and would > love to put them there as well. > >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> >> I thought so too. >> >> But reading the code more closely it might be hard for the blocklayout >> to figure out the right state to call these two. Specially the call to >> blk_finish_plug(). So you might need to add a new LD API such as >> LD()->finish_plug() which is empty for others. >> >> But again inspecting the code it looks like blk_start_plug() is a no-op >> and blk_finish_plug() is specially optimized for the empty case. >> > They are empty only when !CONFIG_BLOCK. I will make it block layout > specific as said above. > You miss understood. At the very top of blk_finish_plug() there is an if (list_empty()) return. So if there was no activity between plug/unplug the function is very fast. But your above plan for alignment+plug sounds very good. Thanks Boaz > Thanks, > Tao >> So is it worth it, the extra effort? I do understand the temptation >> to get lazy here. >> >> Just my $0.017 >> Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
