Messages in this thread | | | From | Sergey Temerkhanov <> | Subject | Re: [PATCH][RFC] AIO: always reinitialize iocb->ki_run_list at the end of aio_run_iocb() | Date | Thu, 24 Jun 2010 21:31:21 +0400 |
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On Wednesday 02 June 2010 01:14:48 Jeff Moyer wrote: > Sergey Temerkhanov <temerkhanov@yandex.ru> writes: > > On Wednesday 26 May 2010 23:38:35 Jeff Moyer wrote: > > ... > OK, you tried two aio_put_req() calls, and it worked, but you thought > > maybe it wasn't the right approach. So: > > So, I've tried another approach (hack) - requeue the kiocb with > > kick_iocb() before calling aio_put_req() in the ki_cancel() callback > > (that's because aio_run_iocb() takes some special actions for the > > canceled kiocbs). And I've found out that kick_iocb() fails because > > aio_run_iocb() does this: > > iocb->ki_run_list.next = iocb->ki_run_list.prev = NULL; > > and only reinitializes iocb->ki_run_list when iocb->ki_retry() returns > > -EIOCBRETRY but kick_iocb() is exported and looks like intended for usage > > (though not recommended). > > You implemented this other hack, and ran into troubles, so you're > modifying the aio core to fix it. Am I wrong in concluding that if you > keep your first solution above, you no longer need this second?
Well, let's forget the reference counting for now since failing kick_iocb() is generally not related to it. I've just described how I've run into it - I could run into it somehow else.
The problem with kick_iocb() is exactly as this: If retry() method returns -EIOCBQUEUED to aio_run_iocb() then any subsequent call to kick_iocb() results in failure. Is it expected behavior?
> > You may also find the following an interesting read: > > http://permalink.gmane.org/gmane.linux.kernel.aio.general/2571 > > Cheers, > Jeff >
-- Regards, Sergey Temerkhanov, Cifronic ZAO
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