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Date: Fri, 26 Jan 2024 16:42:06 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: LKML <linux-kernel@vger.kernel.org>, Linux Trace Devel
 <linux-trace-devel@vger.kernel.org>, Masami Hiramatsu
 <mhiramat@kernel.org>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
 Christian Brauner <brauner@kernel.org>, Ajay Kaher
 <ajay.kaher@broadcom.com>, Geert Uytterhoeven <geert@linux-m68k.org>,
 linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH] eventfs: Have inodes have unique inode numbers
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On Fri, 26 Jan 2024 13:36:20 -0800
Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Fri, 26 Jan 2024 at 13:26, Steven Rostedt <rostedt@goodmis.org> wrote:
> >
> > I'd be happy to change that patch to what I originally did before deciding
> > to copy get_next_ino():
> >
> > unsigned int tracefs_get_next_ino(int files)
> > {
> >         static atomic_t next_inode;
> >         unsigned int res;
> >
> >         do {
> >                 res = atomic_add_return(files + 1, &next_inode);
> >
> >                 /* Check for overflow */
> >         } while (unlikely(res < files + 1));
> >
> >         return res - files;  
> 
> Still entirely pointless.
> 
> If you have more than 4 billion inodes, something is really really wrong.

No, but you can trivially make a loop that creates and destroys
directories that will eventually overflow the count.

-- Steve