On Wed, 4 Feb 2009 13:14:31 +1030 Rusty Russell <rusty@xxxxxxxxxxxxxxx> wrote: > On Tuesday 03 February 2009 14:36:49 Andrew Morton wrote: > > But as you say, rdmsr_on_cpu() is easy to do, using > > smp_call_function_single(). Then we can easily convert all other > > work_on_cpu() callers to smp_call_function_single() and zap > > work_on_cpu(). The best outcome, methinks. > > grepping for set_cpus_allowed reveals the following users in the > first third (when I got tired of it): > > File Function Context Calls > powerpc/kernel/smp.c smp_cpus_done kernel_init smp_ops->setup_cpu() > x86/.../speedstep-ich.c _speedstep_get cpufreq speedstep_get_processor_frequency() > x86/.../powernow-k8.c check_supported_cpu cpufreq cpuid_*() > x86/.../powernow-k8.c powernowk8_target cpufreq mutex_lock, etc > x86/.../powernow-k8.c powernowk8_cpu_init boot/hotplg rdmsr,wrmsr > x86/.../powernow-k8.c powernowk8_get cpufreq rdmsr > x86/.../speedstep-centrino.c get_cur_freq cpufreq rdmsr > x86/.../speedstep-centrino.c centrino_target cpufreq rdmsr,wrmsr > x86/kernel/reboot.c nativ..._shutdown sys_reboot misc > x86/.../microcode_core.c do_microcode_update sys_write microcode_ops->request_microcode_user > x86/.../microcode_core.c reload_store sys_write mutex_lock, etc > > Some of these (reboot) we don't care what they do to cpumask. Some are > poor style, but not critical (boot time). Some can use smp_call_function. > > But there are some which should *not* be frobbing their cpus_allowed, and > really do seem to want a user context. > > I think you're right though: smp_call_function_single (or neat wrappers) > where possible, work_on_cpu which can fail for the others, and we'll just > have to plumb in the error returns. I bet a lot of those can use plain old schedule_work_on(). Could it be that after converting things to smp_call_function_single()/schedule_work_on(), we don't need work_on_cpu()? -- To unsubscribe from this list: send the line "unsubscribe cpufreq" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
