Re: [PATCH] Fix shrink_dcache_parent() against shrink_dcache_memory() race (3rd updated patch)]

[Kirill Korotaev <dev@sw.ru>]

>>>I think that we should go for the first.
>>
>>just an idea which came to my mind:
>>can't we fix it the following way:
>>1. fix select_parent() when called from generic_shutdown_super() to loop 
>>until _all_ dentries are shrinked (not only those, with d_count = 1);
>>this guarentees that no dentries are left.
>>2. no dentries are left, but iput() can be in progress.
>>So can't we simply make invalidate_inodes() to be in a loop with 
>>schedule() until no busy inodes are left?!
> 
> 
> But this hides the places where dput() is called after mntput() and locks up
> when somebody forgets to call dput() at all. And I think we should printk() in
> that situations instead of waiting for them.
I think both: printk and wait.
 From my own personal experience with it: it is better to wait in a loop 
and be able to collect information, then to crash.

Thanks,
Kirill