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Date:   Wed, 4 Mar 2020 05:28:12 -0800
From:   Matthew Wilcox <willy@infradead.org>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     "Eric W. Biederman" <ebiederm@xmission.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [RFC][PATCHSET] sanitized pathwalk machinery (v3)
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On Wed, Mar 04, 2020 at 06:55:47AM +0000, Al Viro wrote:
> On Tue, Mar 03, 2020 at 11:23:39PM -0600, Eric W. Biederman wrote:
> > Do the xfs-tests cover that sort of thing?
> > The emphasis is stress testing the filesystem not the VFS but there is a
> > lot of overlap between the two.
> 
> I do run xfstests.  But "runs in KVM without visible slowdowns" != "won't
> cause them on 48-core bare metal".  And this area (especially when it
> comes to RCU mode) can be, er, interesting in that respect.
> 
> FWIW, I'm putting together some litmus tests for pathwalk semantics -
> one of the things I'd like to discuss at LSF; quite a few codepaths
> are simply not touched by anything in xfstests.

Might be more appropriate for LTP than xfstests?  will-it-scale might be
the right place for performance benchmarks.