Messages in this thread | | | Date | Thu, 22 Mar 2001 10:45:07 -0800 | From | george anzinger <> | Subject | Re: current->need_reshed, can it be a global flag ? |
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Parity Error wrote: > > instead of need_reshed being a per-task flag, could it be > as a global flag ?, since every time current->need_reshed > is checked, schedule() is just called to pick another > process. > > --- But for which cpu? Really this is a short cut to provide a per cpu area that I think works very well, thank you.
Putting it in a real cpu data area would make access slower. The "current" pointer is either very quickly computed or pre loaded in a register (depends on the platform) so it is about as fast as it can get as it is.
Also, the flag is often checked by selective preemption code in the kernel. Even more often by the full preemption patch.
Nuf said George - 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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