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From: Hillf Danton <hdanton@sina.com>
To: "NeilBrown" <neilb@suse.de>
Cc: "Alexander Viro" <viro@zeniv.linux.org.uk>,
	"Christian Brauner" <brauner@kernel.org>,
	"Jan Kara" <jack@suse.cz>,
	"Peter Zijlstra" <peterz@infradead.org>,
	"Linus Torvalds" <torvalds@linux-foundation.org>,
	linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 08/11] VFS: add inode_dir_lock/unlock
Date: Tue, 24 Dec 2024 18:26:11 +0800
Message-ID: <20241224102614.424-1-hdanton@sina.com>
In-Reply-To: <173498616860.11072.11978717859547245956@noble.neil.brown.name>
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On Tue, 24 Dec 2024 07:36:08 +1100 NeilBrown <neilb@suse.de>
> On Mon, 23 Dec 2024, Hillf Danton wrote:
> > On Mon, 23 Dec 2024 14:10:07 +1100 NeilBrown <neilb@suse.de>
> > > On Sat, 21 Dec 2024, Hillf Danton wrote:
> > > > Inventing anything like mutex sounds bad.
> > > 
> > > In general I would agree.  But when the cost of adding a mutex exceeds
> > > the cost of using an alternate solution that only requires 2 bits, I
> > > think the alternate solution is justified.
> > > 
> > Inode deserves more than the 2 bits before such a solution is able to
> > rework mutex.
> 
> I'm sorry but I don't understand what you are saying.  Could you please
> give more details about your concern?
> Are you concerned about correctness?  Performance?  Maintainability?
> Something else?
>
It is that you are adding a pair of honey bee wings to A380, so no takeoff
can be expected.