On Sun, 2012-04-01 at 00:33 +0800, Paul E. McKenney wrote: > Although there have been numerous complaints about the complexity of > parallel programming (especially over the past 5-10 years), the plain > truth is that the incremental complexity of parallel programming over > that of sequential programming is not as large as is commonly believed. > Despite that you might have heard, the mind-numbing complexity of modern > computer systems is not due so much to there being multiple CPUs, but > rather to there being any CPUs at all. In short, for the ultimate in > computer-system simplicity, the optimal choice is NR_CPUS=0. > > This commit therefore limits kernel builds to zero CPUs. This change > has the beneficial side effect of rendering all kernel bugs harmless. > Furthermore, this commit enables additional beneficial changes, for > example, the removal of those parts of the kernel that are not needed > when there are zero CPUs. > > Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> > Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> > --- Hmm... I believe you could go one step forward and allow negative values as well. Antimatter was proven to exist after all. Hint : nr_cpu_ids is an "int", not an "unsigned int" Bonus: Existing bugs become "must have" features. Of course there is no hurry and this can wait 365 days.