Re: [RFC patch 08/18] cnt32_to_63 should use smp_rmb()

[David Howells]

Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxx> wrote:

> First off, using this macro with get_cycles() is simply buggy, because the
> macro expects _perfect_ order of timestamps, no skew whatsoever, or
> otherwise time could jump.

Erm...  Why can't I pass it get_cycles()?  Are you saying that sched_clock()
in MN10300 is wrong for it's use of get_cycles() with cnt32_to_63()?

> 	__x.lo = readl(cnt_lo); /* mmio read */

readl() might insert an extra barrier instruction.  Not only that, io_addr
must be unsigned long.

David
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