Messages in this thread |  | | From | Arnd Bergmann <> | | Subject | Re: [PATCH v2] clocksource: exynos-mct: Register the timer for stable udelay | | Date | Thu, 19 Jun 2014 12:29:55 +0200 |
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On Thursday 19 June 2014 15:51:58 amit daniel kachhap wrote: > I also didn't want to use macros but used as a last option. you want > me to put more comments here? > Or something like below is also possible for checking the size of > (unsigned long) in runtime. > > unsigned long x; > unsigned int size = (char *)(&x + 1) - (char *)(&x);
reimplementing "sizeof (long)"?
> if (size == 4) > return __raw_readl(reg_base + EXYNOS4_MCT_G_CNT_L);
readl_relaxed(), certainly
> else > return exynos4_frc_read(&mct_frc); > > But this involves extra computation which should not be used for time > critical functions.
sizeof is a constant expression, the compiler will optimize this.
Arnd
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