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Date:   Sun, 4 Oct 2020 21:05:31 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Marc Zyngier <maz@kernel.org>
Subject: Re: [RFC][PATCHSET] epoll cleanups
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On Sun, Oct 04, 2020 at 11:08:11AM -0700, Linus Torvalds wrote:
> On Sat, Oct 3, 2020 at 7:36 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
> >
> >         Locking and especially control flow in fs/eventpoll.c is
> > overcomplicated.  As the result, the code has been hard to follow
> > and easy to fuck up while modifying.
> 
> Scanning through the patches they all look superficially ok to me, but
> I'm wondering how much test coverage you have (because I'm wondering
> how much test coverage we have in general for epoll).

Besides the in-tree one (tools/testing/selftests/filesystems/epoll)
and LTP stuff (testcases/kernel/syscalls/epoll) - only davidel's
epoll_test.c.  Plus slapped together "let's try to make it go through
that codepath" stuff (combined with printks in fs/eventpoll.c)...