Messages in this thread | | | Date | Fri, 15 Feb 2002 08:51:39 -0500 | From | Jeff Garzik <> | Subject | Re: [PATCH] move task_struct allocation to arch |
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Roman Zippel wrote: > > Hi, > > On Fri, 15 Feb 2002, David Howells wrote: > > > Firstly, in response to me having supplied a patch that made a set of four > > byte-size values as the status area in the task_struct: > > > > | For the future, the biggest thing I'd like to see is actually to make > > | "work" be a bitmap, because the "bytes are atomic" approach simply isn't > > | portable anyway, so we might as well make things _explicitly_ atomic and > > | use bit operations. Otherwise the alpha version of "work" would have to be > > | four bytes per "bit" of information, which sounds really excessive. > > As I mentioned before I more like the byte approach, since atomic bit > field handling is quite expensive on most architectures, where a simple > set/clear byte is only one or two instructions, if there is byte > load/store instruction. So I'd really like to see to leave the decision to > the architecture, whether to use bit or byte fields.
We have tons of code already using atomic test_and_set_bit type stuff... why not just make sure your bit set/clear stuff is fast? :)
Jeff
-- Jeff Garzik | "I went through my candy like hot oatmeal Building 1024 | through an internally-buttered weasel." MandrakeSoft | - goats.com - 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/
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