From: Rusty Russell <rusty@rustcorp.com.au>
To: Zach Brown <zach.brown@oracle.com>
Subject: Re: [PATCH 5/6] syslets: add generic syslets infrastructure
Date: Wed, 9 Jan 2008 13:03:57 +1100
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       Jens Axboe <jens.axboe@oracle.com>,
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       Dan Williams <dan.j.williams@gmail.com>, Jeff Moyer <jmoyer@redhat.com>,
       Simon Holm Thogersen <odie@cs.aau.dk>, suresh.b.siddha@intel.com
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On Friday 07 December 2007 10:20:18 Zach Brown wrote:
> The indirect syslet arguments specify where to store the completion and
> what function in userspcae to return to once the syslet has been executed. 
> The details of how we pass the indirect syslet arguments needs help.

Hi Zach,

    Firstly, why not just specify an address for the return value and be done 
with it?  This infrastructure seems overkill, and you can always extend later 
if required.

Secondly, you really should allow integration with an eventfd so you don't 
make the posix AIO mistake of providing a poll-incompatible interface.

Finally, and probably most alarmingly, AFAICT randomly changing TID will break 
all threaded programs, which means this won't be fitted into existing code 
bases, making it YA niche Linux-only API 8(

Cheers,
Rusty.
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