[PATCH 2/2] clk: Move init fields from clk to clk_hw
From: s.hauer@pengutronix.de (Sascha Hauer)
Date: 2012-03-20 22:40:47
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On Tue, Mar 20, 2012 at 01:14:51PM -0700, Saravana Kannan wrote:
On 03/20/2012 11:14 AM, Sascha Hauer wrote:quoted
On Tue, Mar 20, 2012 at 03:17:10AM -0700, Saravana Kannan wrote:quoted
On Tue, March 20, 2012 2:40 am, Sascha Hauer wrote:quoted
On Tue, Mar 20, 2012 at 12:54:55AM -0700, Saravana Kannan wrote:quoted
I am using these functions and don't need a static array, I just call the functions with the desired parameters.Sure, then let's leave it in. Curious, where do you get the desired parameters from? Is it static date in code or is it from DT? You somehow probe it?It's not from DT. See this thread: http://www.spinics.net/lists/arm-kernel/msg165839.htmlAh, I see. That's a lot of functions calls. I think it would be much more efficient if you just have an array and loop over it. With my patch, you can just call a single register function for all these clocks.
I was curious and gave it a try. I registered a fixed clock and 100 gates as child clocks. I tried both DEFINE_CLK_GATE and clk_register_gate. It turned out there was no difference in speed.
quoted
The difference is that a struct clk_initializer is only used to initialize a clock and not actively used by the clock framework. But as you already mentioned using a copy inside the clock framework has the same effect.My opinion on this is to follow a wait and watch approach on the "flags" field. I really can't think of a safe way anyone can misuse it. If people start doing that, we can just do the copy and let them deal with their broken code. Until that happens, I don't want to waste time/space by copying it. The rest of the fields aren't actively used by the common clock code after init.
Actually you will save space by copying it because you can put the initializers in __initdata and throw the initializers of unused SoCs compiled into the kernel away during runtime. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |