From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [PATCH 1/2] serial: amba-pl011: use cpu_relax when polling registers Date: Sat, 12 Dec 2015 22:04:59 -0800 Message-ID: <20151213060459.GA30609@kroah.com> References: <1446562867-5693-1-git-send-email-timur@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1446562867-5693-1-git-send-email-timur@codeaurora.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: Timur Tabi Cc: peter@hurleysoftware.com, andre.przywara@arm.com, Linus Walleij , Andrew.Jackson@arm.com, linux-serial@vger.kernel.org, jslaby@suse.com, jun.nie@linaro.org, linux-arm-kernel@lists.infradead.org List-Id: linux-serial@vger.kernel.org On Tue, Nov 03, 2015 at 09:01:06AM -0600, Timur Tabi wrote: > Busy loops that poll on a register should call cpu_relax(). On some > architectures, it can lower CPU power consumption or yield to a > hyperthreaded twin processor. It also serves as a compiler barrier, > so it can replace barrier() calls. > > Signed-off-by: Timur Tabi > Reviewed-by: Peter Hurley > --- > drivers/tty/serial/amba-pl011.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > Doesn't apply to my tree :( From mboxrd@z Thu Jan 1 00:00:00 1970 From: greg@kroah.com (Greg Kroah-Hartman) Date: Sat, 12 Dec 2015 22:04:59 -0800 Subject: [PATCH 1/2] serial: amba-pl011: use cpu_relax when polling registers In-Reply-To: <1446562867-5693-1-git-send-email-timur@codeaurora.org> References: <1446562867-5693-1-git-send-email-timur@codeaurora.org> Message-ID: <20151213060459.GA30609@kroah.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Nov 03, 2015 at 09:01:06AM -0600, Timur Tabi wrote: > Busy loops that poll on a register should call cpu_relax(). On some > architectures, it can lower CPU power consumption or yield to a > hyperthreaded twin processor. It also serves as a compiler barrier, > so it can replace barrier() calls. > > Signed-off-by: Timur Tabi > Reviewed-by: Peter Hurley > --- > drivers/tty/serial/amba-pl011.c | 11 ++++++----- > 1 file changed, 6 insertions(+), 5 deletions(-) > Doesn't apply to my tree :(