On Fri, Mar 25, 2005 at 11:24:05AM -0800, Ed Martini wrote: > 1. If the first part of the if were an ifdef instead it would result in > a code size reduction as well as a runtime performance gain. You should spend a little time playing with an optimizing compiler. They're capable of working out when a condition will always be false. > 2. In atomic.h the "C lang stuff" is wrapped with a spinlock. In the > SMP case the spinlock will result in code that contains ll and sc > instructions, so I infer that there are no SMP system configs that use > CPUs that don't have the ll and sc instructions. That's correct. It is not practical to implement SMP without a mutex primitive. -- Daniel Jacobowitz CodeSourcery, LLC
