Messages in this thread | | | From | Con Kolivas <> | Subject | Re: [PATCH] mm: Implement Swap Prefetching v22 | Date | Fri, 10 Feb 2006 11:08:46 +1100 |
| |
On Friday 10 February 2006 05:04, Nikita Danilov wrote: > Nick Piggin writes: > > [...] > > > > +/* > > > + * We check to see no part of the vm is busy. If it is this will > > > interrupt + * trickle_swap and wait another PREFETCH_DELAY. > > > Purposefully racy. + */ > > > +inline void delay_swap_prefetch(void) > > > +{ > > > + __set_bit(0, &swapped.busy); > > > +} > > > + > > > > Test this first so you don't bounce the cacheline around in page > > reclaim too much. > > Shouldn't we have special macros/inlines for this? Like, e.g., > > static inline void __set_bit_weak(int nr, volatile unsigned long * addr) > { > if (!__test_bit(nr, addr)) > __set_bit(nr, addr); > } > > ? These test-then-set sequences start to proliferate throughout the code.
Maybe.
There isn't actually a non-atomic __test_bit anyway, only a test_bit. The non-atomic __test_and_set_bit already exists, but that sets the bit regardless of what the bit was as far as I can tell.
Cheers, Con - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |