FUJITA Tomonori wrote: > On Sun, 26 Oct 2008 11:38:04 +0200 > Boaz Harrosh <bharrosh@xxxxxxxxxxx> wrote: > >> FUJITA Tomonori wrote: >>> CC'ed Jens, >>> >>> On Wed, 22 Oct 2008 19:27:35 -0700 >>> Seokmann Ju <seokmann.ju@xxxxxxxxxx> wrote: >>> >>>> And it seems like that the panic is happening due to the fact that >>>> blk_delete_timer() is not called upon having completion of the service. >>>> In other words, the block layer calls blk_add_timer() prior to >>>> dispatch the service but, it doesn't call blk_delete_timer() when it >>>> returned. >>> Yeah, we need to call blk_delete_timer somewhere. >>> >>> >>>> Just for heck of it, I've tried out by adding blk_delete_timer() in >>>> the ~/block/blk-exec.c:blk_end_sync_rq() and it seems fixes the problem. >>> I think blk_end_sync_rq() is not the good place. From the perspective >>> of bsg, we need to handle both blk_execute_rq_nowait and >>> blk_execute_rq. >>> >>> >>>> Seems like that there are APIs in the block layer that are call the >>>> blk_delete_timer(), including, >>>> - blk_end_io() >>>> - __blk_end_request() >>>> >>>> Could you guide me what is right way to fix the problem? >>> Exporting blk_delete_timer is one option, but it doesn't look very >>> nice (since the block layer doesn't export any details about its timer >>> infrastructure), I think. Modifying blk_end_io() to make it usable for >>> requests via something like bsg might be better. >>> >>> Anyway, we need to ask Jens. >>> >>> Jens, fc people have working on fc pass through support via bsg, which >>> hooks bsg's request queue on fc transport objects (We did the similar >>> thing for sas transport). >>> >>> We want the timeout feature for fc pass through and I think that it's >>> nice to use the block layer timeout feature for it. But the users of >>> bsg request queue don't need (or call) APIs such as >>> end_that_request_last to call blk_delete_timer internally. How should >>> these users call blk_delete_timer? >> TOMO Hi >> If a command is queued by bsg to a scsi device, which is posible. Then >> blk_end_request() is called by scsi-ml. So it does work. > > It doesn't work for bsg's scsi transport pass through stuff such as > SMP (sas management protocol, we already support) and FC. Virtually, > they don't use scsi-ml. > Right, I know that, that's why I say. > >> I think that all block-queue consumers should call one of >> blk_end_request(), > > This is kinda what I suggested in the previous mail but as I wrote, > some of them don't now. > I think they should, specially if they're going to use the timer. The way I see it they must. It's kind of a block layer API thing. Someone calls blk_execute_xx then eventually someone needs to call blk_end_request. You could call it from bsg but only temporary until all are fixed. (because you will need an ugly check to see if request was not already ended) > >> there are lots to choose from. We don't need >> a new API. It will work with or without data, and it does what >> you want. Boaz -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
