Re: Float numbers in module programming

From: Jan Engelhardt
Date: Thu Mar 30 2006 - 03:08:25 EST


>
>This used to be a FAQ. The floating-point coprocessor in ix86
>machines is a shared resource. There is only one. Therefore,
>the state of the floating-point unit needs to be saved and
>restored across all context switches. Because this is expensive
>in terms of CPU time used, it is not saved and restored during
>system calls. This means that if you use the coprocessor in
>the kernel, you may screw up somebody's mathematics,

"somebody" is the current process, is not it? What if used in kthreads?


Jan Engelhardt
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