So, This is a proposition to handle the cputime accounting without the tick to prepare for stopping the tick further idle.
I have managed to reuse and generalize the kernel/user boundary hooks used by RCU. This way we can minimize the changes in archs that don't support virtual cputime and we can also switch between vtime and tick based accounting to minimize the overhead depending on the tick behaviour. This is based on top of rcu/idle branch in Paul's tree and my vtime consolidation series: https://lkml.org/lkml/2012/6/20/762 (still waiting to be picked btw). You, adventurer, can pull from: git://github.com/fweisbec/linux-dynticks.git vtime/generic Frederic Weisbecker (5): user_hooks: New user hooks subsystem cputime: Don't allow virtual and irq finegrained cputime accounting simultaneously cputime: Allow dynamic switch between tick/virtual based cputime accounting cputime: Rename account_system_vtime to account_vtime cputime: Generic on-demand virtual cputime accounting arch/Kconfig | 10 +- arch/ia64/include/asm/cputime.h | 5 + arch/ia64/kernel/time.c | 6 +- arch/powerpc/include/asm/cputime.h | 5 + arch/powerpc/kernel/time.c | 10 +- arch/s390/include/asm/cputime.h | 5 + arch/s390/kernel/vtime.c | 6 +- arch/x86/Kconfig | 2 +- arch/x86/include/asm/{rcu.h => user_hooks.h} | 12 +- arch/x86/kernel/ptrace.c | 6 +- arch/x86/kernel/signal.c | 5 +- arch/x86/kernel/traps.c | 2 +- arch/x86/mm/fault.c | 2 +- include/asm-generic/cputime.h | 7 + include/linux/hardirq.h | 8 +- include/linux/kernel_stat.h | 13 ++ include/linux/kvm_host.h | 4 +- include/linux/rcupdate.h | 2 - include/linux/sched.h | 13 +-- include/linux/user_hooks.h | 36 ++++++ init/Kconfig | 35 ++++-- kernel/Makefile | 1 + kernel/fork.c | 3 +- kernel/rcutree.c | 42 +------- kernel/sched/core.c | 9 +- kernel/sched/cputime.c | 159 +++++++++++++++++++++---- kernel/softirq.c | 6 +- kernel/time/tick-sched.c | 28 ++--- kernel/user_hooks.c | 56 +++++++++ 29 files changed, 348 insertions(+), 150 deletions(-) rename arch/x86/include/asm/{rcu.h => user_hooks.h} (56%) create mode 100644 include/linux/user_hooks.h create mode 100644 kernel/user_hooks.c -- 1.7.5.4 -- 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/
