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From: Thomas Gleixner <tglx@linutronix.de>
To: Ivo Sieben <meltedpianoman@gmail.com>
Cc: linux-serial@vger.kernel.org, RT <linux-rt-users@vger.kernel.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	Greg KH <gregkh@linuxfoundation.org>
Subject: Re: [PATCH-v3] tty: Use raw spin lock to protect the TTY read section
Date: Mon, 4 Feb 2013 16:33:33 +0100 (CET)	[thread overview]
Message-ID: <alpine.LFD.2.02.1302041616030.11905@ionos> (raw)
In-Reply-To: <1359376321-27274-1-git-send-email-meltedpianoman@gmail.com>

On Mon, 28 Jan 2013, Ivo Sieben wrote:
> @Thomas Gleixner & Steven Rostedt:
> Greg Kroah-Hartman responded to this patch: "And this really makes a
> difference? I'd like to hear the rt developers opinion of this."

In general the sleeping spinlocks overhead can be quite visible and
AFAICT the ntty read_lock only protects very short code pathes which
manipulate the read buffer and related data. So from an RT perspective
this lock can be a real spinlock even on RT.

Reviewed-by: Thomas Gleixner <tglx@linutronix.de>

Thanks,

	tglx




      reply	other threads:[~2013-02-04 15:33 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-09-20 14:09 [PATCH] tty: Use raw spin lock to protect the TTY read section Ivo Sieben
2013-01-24 10:34 ` [PATCH-v2] " Ivo Sieben
2013-01-25 16:13   ` Greg KH
2013-01-28 12:15     ` Ivo Sieben
2013-01-28 12:32       ` [PATCH-v3] " Ivo Sieben
2013-02-04 15:33         ` Thomas Gleixner [this message]

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