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From:   Chuck Lever III <chuck.lever@oracle.com>
To:     Neil Brown <neilb@suse.de>
CC:     Amir Goldstein <amir73il@gmail.com>,
        Jeff Layton <jlayton@kernel.org>,
        Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Subject: Re: [PATCH v2] nfsd: more robust allocation failure handling in
 nfsd_file_cache_init
Thread-Topic: [PATCH v2] nfsd: more robust allocation failure handling in
 nfsd_file_cache_init
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Date:   Thu, 24 Feb 2022 21:56:07 +0000
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> On Feb 24, 2022, at 4:49 PM, NeilBrown <neilb@suse.de> wrote:
>=20
> On Fri, 25 Feb 2022, Amir Goldstein wrote:
>> The nfsd file cache table can be pretty large and its allocation
>> may require as many as 80 contigious pages.
>>=20
>> Employ the same fix that was employed for similar issue that was
>> reported for the reply cache hash table allocation several years ago
>> by commit 8f97514b423a ("nfsd: more robust allocation failure handling
>> in nfsd_reply_cache_init").
>>=20
>> Fixes: 65294c1f2c5e ("nfsd: add a new struct file caching facility to nf=
sd")
>> Link: https://lore.kernel.org/linux-nfs/e3cdaeec85a6cfec980e87fc294327c0=
381c1778.camel@kernel.org/
>> Suggested-by: Jeff Layton <jlayton@kernel.org>
>> Signed-off-by: Amir Goldstein <amir73il@gmail.com>
>> ---
>>=20
>> Since v1:
>> - Use kvcalloc()
>> - Use kvfree()
>=20
> I think this is a good improvement, but it would be really nice to
> replace this bespoke hash table with an rhashtable.  They we wouldn't
> need to worry about these trivial details.

I agree -- I didn't want to saddle Jeff or Amir with pulling
on that chain. But I'm willing to review patches that attempt
that kind of replacement (same for the DRC hash table).


--
Chuck Lever