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Date: Fri, 1 Nov 2024 14:15:57 +0100
From: Christian Brauner <brauner@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>, 
	linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: generic_permission() optimization
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On Thu, Oct 31, 2024 at 03:17:18PM -1000, Linus Torvalds wrote:
> On Thu, 31 Oct 2024 at 12:34, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > So I'd rather start with just the cheap inode-only "ACL is clearly not
> > there" check, and later if we find that the ACL_NOT_CACHED case is
> > problematic do we look at that.
> 
> Actually, if I switch the tests around so that I do the permission bit
> check first, it becomes very natural to just check IS_POSIXACL() at
> the end (where we're about to go to the slow case, which will be
> touching i_sb anyway).

Applied.