On Sun, Mar 13, 2016 at 11:28:54AM +0200, Ebru Akagunduz wrote: > Currently, vmstat can calculate specific vm event with all_vm_events() > however it allocates all vm events to stack. This patch introduces > a helper to sum value of a specific vm event over all cpu, without > loading all the events. > > Signed-off-by: Ebru Akagunduz <[email protected]> > --- > Changes in v2: > - this patch newly created in this version > - create sum event function to > calculate particular vm event (Kirill A. Shutemov) > > include/linux/vmstat.h | 2 ++ > mm/vmstat.c | 12 ++++++++++++ > 2 files changed, 14 insertions(+) > > diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h > index 73fae8c..add0cc1 100644 > --- a/include/linux/vmstat.h > +++ b/include/linux/vmstat.h > @@ -53,6 +53,8 @@ static inline void count_vm_events(enum vm_event_item item, > long delta) > > extern void all_vm_events(unsigned long *); > > +extern unsigned long sum_vm_event(enum vm_event_item item); > + > extern void vm_events_fold_cpu(int cpu); > > #else
You need dumy definition of the function for !CONFIG_VM_EVENT_COUNTERS case here. Otherwise build will fail. See 0-day report. Otherwise looks good to me: Acked-by: Kirill A. Shutemov <[email protected]> > diff --git a/mm/vmstat.c b/mm/vmstat.c > index 5e43004..b76d664 100644 > --- a/mm/vmstat.c > +++ b/mm/vmstat.c > @@ -34,6 +34,18 @@ > DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}}; > EXPORT_PER_CPU_SYMBOL(vm_event_states); > > +unsigned long sum_vm_event(enum vm_event_item item) > +{ > + int cpu; > + unsigned long ret = 0; > + > + get_online_cpus(); > + for_each_online_cpu(cpu) > + ret += per_cpu(vm_event_states, cpu).event[item]; > + put_online_cpus(); > + return ret; > +} > + > static void sum_vm_events(unsigned long *ret) > { > int cpu; > -- > 1.9.1 > > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to [email protected]. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"[email protected]";> [email protected] </a> -- Kirill A. Shutemov
