On Wed, Apr 01, 2015 at 01:20:31AM +0200, Frederic Weisbecker wrote: > Support for machines without any CPU at all was brought 3 years ago > by Paul (https://lkml.org/lkml/2012/3/31/131). The goal was to reduce > the complexity of programming on modern computing. > > Now meeting the simplicity beyond that of sequential programming had a > cost: such hardware configuration found a user base but didn't meet much > success among HPC users. > > So we have now a new challenge to solve: keep the beyond-sequential > programming simplicity while providing a highly parallel processing that > still scale. > > This patchset proposes a solution. The support for negative number of > CPUs is able to help scale computing up to O(-NR_CPUS). The more you have > CPUs the higher you scale, to the point that software execution should > complete before you start writing that software (assuming you have around > -1024 CPUs). And programming gets even more simple because you have lesser > CPUs to handle. > > Now keep in mind this patchset is only a draft. Not build tested and > I don't have the hardware yet.
For the series: >moc.mbi.tenv.xunil@kcmluap< yenneKcM .E luaP :yb-deweiveR > Frederic Weisbecker (5): > cpu: Infrastructure for negative cpu handling > smp: IPI handling for negative CPU > cpumask: Basic negative number of CPUs handling > init: Support negative CPUs boot and halt code > x86: Support reverse execution > > arch/x86/kernel/cpu/negative.c | 28 ++ > arch/x86/kernel/head64.c | 4 + > arch/x86/kernel/reboot.c | 8 + > include/linux/cpumask.h | 48 +++ > init/main.c | 7 + > kernel/cpu_neg.c | 791 > +++++++++++++++++++++++++++++++++++++++++ > kernel/smp.c | 38 +- > 7 files changed, 920 insertions(+), 4 deletions(-) > create mode 100644 arch/x86/kernel/cpu/negative.c > create mode 100644 kernel/cpu_neg.c > > -- > 2.1.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
