On 07/18/2012 03:51 PM, Andrew Morton wrote:
On Tue, 17 Jul 2012 17:41:40 +0100
Catalin Marinas <catalin.mari...@arm.com> wrote:
This patch allows an architecture to not define CLOCK_TICK_RATE, in
which case ACTHZ defaults to (HZ << 8).
No reason was given for this change.
So those people who are wondering "why don't you just define
CLOCK_TICK_RATE" are made all sad.
I just queued this patch with a revised commit message:
jiffies: Allow CLOCK_TICK_RATE to be undefined
CLOCK_TICK_RATE is a legacy constant that defines the timer
device's granularity. On hardware with particularly coarse
granularity, this constant is used to reduce accumulated
time error when using jiffies as a clocksource, by calculating
the hardware's actual tick length rather then just assuming
it is 1sec/HZ.
However, for the most part this is unnecessary, as most modern
systems don't use jiffies for their clocksource, and their
tick device is sufficiently fine grained to avoid major error.
Thus, this patch allows an architecture to not define
CLOCK_TICK_RATE, in which case ACTHZ defaults to (HZ << 8).
Let me know if you'd like to see further improvements.
thanks
-john
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
