Messages in this thread | | | Date | Wed, 08 Oct 2008 08:17:31 +0900 | From | Tejun Heo <> | Subject | Re: sysfs: tagged directories not merged completely yet |
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Hello, a bit of additions after some sleep.
Tejun Heo wrote: > Eric W. Biederman wrote: > IIRC, the original readdir implementation put a cursor entry to walk > through the children list. The implementation was horribly broken in > a number of different ways (ISTR problems with locking and multiple > and different type of walkers) and I just gutted out all the > complexity out and made it simple as getting it correct was far more > important and there seemed to be little need for optimization. > > Yeah, using RCU sounds like a plan.
Heh... it did sound like a plan but I don't think the plan would solve the problem. filldir can't be put in rcu read critical section. :-p
>> The revalidate on access model doesn't appear to have a way to track >> remote renames. Something sysfs supports. > > Yeap, IIRC, one of the reasons why sysfs wasn't converted over to > sysfs was because sysfs guarantees inode doesn't change over rename or > move so that notifications keep working over renames.
s/over to sysfs/over to revalidation/ and s/inode/dentry/. Maybe we can just ignore dnotify? :-(
Thanks.
-- tejun
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