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Date: Tue, 11 Jun 2024 21:57:18 -0400
From: Steven Rostedt <rostedt@goodmis.org>
To: Guenter Roeck <linux@roeck-us.net>
Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, Masami
 Hiramatsu <mhiramat@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
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Subject: Re: [PATCH v4 01/13] ring-buffer: Allow mapped field to be set
 without mapping
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On Tue, 11 Jun 2024 21:39:37 -0400
Steven Rostedt <rostedt@goodmis.org> wrote:

> > 
> > Maybe explain why sometimes __rb_inc_dec_mapped() is called to
> > increment or decrement ->mapped, and sometimes it id done directly ?
> > I can see that the function also acquires the buffer mutex, which
> > isn't needed at the places where mapped is incremented/decremented
> > directly, but common code would still be nice, and it is odd to see
> > over/underflows handled sometimes but not always.  
> 
> Sure. I'll add comments explaining more.

And I found a bug with this code. It assumes that mapped will be equal
to 1 if it's the last mapping. That will no longer be the case.

-- Steve