Re: [PATCH] reduce stack usage of NFS (was Re: How to safely reduce...)

["Randy.Dunlap" <rddunlap@osdl.org>]

Denis Vlasenko wrote:
>>>>I can convert these into kmalloc'ed variants but hesitate to do so
>>>>because of possible 'need to kmalloc in order to free memory for kmalloc'
>>>>deadlocks.
>>>
>>>how about a memory pool?
>>>
>>>It's not THE solution but I suspect the depth of callchains of these isn't too deep so it would work
>>
>>I can't see that any of the callchains Denis listed can deadlock. None
>>of them appear to lie in the memory reclaim paths.
> 
> 
> This patch reduces stack usage to below 100 bytes for
> the following functions:
> 
>                        stack usage in 2.6.9
> nfs3_proc_create:             544
> _nfs4_do_open:                516
> nfs_readdir:                  412
> nfs_symlink:                  368
> _nfs4_open_delegation_recall: 368
> nfs3_proc_rename:             364
> _nfs4_open_reclaim:           364
> nfs_mknod:                    352
> nfs_mkdir:                    352
> nfs_proc_create:              344
> nfs3_proc_link:               328
> nfs_lookup_revalidate:        312
> nfs_lookup:                   292
> 
> (btw: in function nfs_readdir: local variable 'desc' seem to be
> easily replaceable with &my_desc, or am I missing something?)
> 
> Compile tested only. I can't run test it until next Wednesday :(
> 
> Please review, especially for leaks on error paths.

Hi Denis,
I checked all of it.  Looks right & it builds.

-- 
~Randy