On 26 January 2011 18:32, Frederic Weisbecker <fweisbec@xxxxxxxxx> wrote: > On Tue, Jan 25, 2011 at 09:54:59AM +0100, Vincent Guittot wrote: >> Please find below a new proposal for adding trace events for cpu hotplug. >> The goal is to measure the latency of each part (kernel, architecture) >> and also to trace the cpu hotplug activity with other power events. I >> have tested these traces events on an arm platform. >> >> Subject: [PATCH 1/2] add cpu hotplug tracepoints >> >> this patch adds new events for cpu hotplug tracing >> * plug/unplug sequence >> * core and architecture latency measurements >> >> Signed-off-by: Vincent Guittot <vincent.guittot@xxxxxxxxxx> >> --- >> kernel/cpu.c | 17 +++++++++++++++++ >> 1 files changed, 17 insertions(+), 0 deletions(-) >> >> diff --git a/kernel/cpu.c b/kernel/cpu.c >> index 156cc55..f04e9cf 100644 >> --- a/kernel/cpu.c >> +++ b/kernel/cpu.c >> @@ -16,6 +16,9 @@ >> #include <linux/mutex.h> >> #include <linux/gfp.h> >> >> +#define CREATE_TRACE_POINTS >> +#include <trace/events/cpu_hotplug.h> >> + >> #ifdef CONFIG_SMP >> /* Serializes the updates to cpu_online_mask, cpu_present_mask */ >> static DEFINE_MUTEX(cpu_add_remove_lock); >> @@ -200,7 +203,9 @@ static int __ref take_cpu_down(void *_param) >> int err; >> >> /* Ensure this CPU doesn't handle any more interrupts. */ >> + trace_cpu_hotplug_arch_disable_start((unsigned int)(param->hcpu)); >> err = __cpu_disable(); >> + trace_cpu_hotplug_arch_disable_end((unsigned int)(param->hcpu)); > > You should create a cpu var instead of doing that not very beautiful cast > twice. > OK > Probably we should eventually rename arch_disable into just disable. > > And same for die, because otherwise the name is quite long. > If we remove the arch extension of these names, we will have trace_cpu_hotplug_arch_up for __cpu_up (trace_cpu_hotplug_up is already used) and trace_cpu_hotplug_disable for __cpu_disable. would that be acceptable ? > Other than that, looks all good to me. > > Thanks. > -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
