Re: Calling current() from interrupt context

[Ralf Baechle]

On Sun, Oct 08, 2000 at 04:19:01PM -0700, Mitchell Blank Jr wrote:

> Some do (look at asm-sparc/smp.h).  However, linux does everything possible
> to make dereferencing "current" as fast as possible, so actually just
> looping it up there is pretty damn efficient.  We need to keep track of the
> last cpu a processor ran on anyway to do cpu-affinity heuristics in the
> scheduler.  So this implementation is quite optimal, actually.

Actually it doesn't.  We've mostly optimized for code size but not really
for performance.  The effects of the same members of a task_struct being
mapped to the same cacheline can be clearly demonstrated in benchmarks.

  Ralf
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