| Message ID | 20220210224933.379149-25-yury.norov@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | None | expand |
On Thu, Feb 10, 2022 at 02:49:08PM -0800, Yury Norov wrote: > mm/vmstat.c code calls cpumask_weight() to check if any bit of a given > cpumask is set. We can do it more efficiently with cpumask_empty() because > cpumask_empty() stops traversing the cpumask as soon as it finds first set > bit, while cpumask_weight() counts all bits unconditionally. > > Signed-off-by: Yury Norov <yury.norov@gmail.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> > --- > mm/vmstat.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/vmstat.c b/mm/vmstat.c > index d5cc8d739fac..27a94afd4ee5 100644 > --- a/mm/vmstat.c > +++ b/mm/vmstat.c > @@ -2041,7 +2041,7 @@ static void __init init_cpu_node_state(void) > int node; > > for_each_online_node(node) { > - if (cpumask_weight(cpumask_of_node(node)) > 0) > + if (!cpumask_empty(cpumask_of_node(node))) > node_set_state(node, N_CPU); > } > } > @@ -2068,7 +2068,7 @@ static int vmstat_cpu_dead(unsigned int cpu) > > refresh_zone_stat_thresholds(); > node_cpus = cpumask_of_node(node); > - if (cpumask_weight(node_cpus) > 0) > + if (!cpumask_empty(node_cpus)) > return 0; > > node_clear_state(node, N_CPU); > -- > 2.32.0 > >
diff --git a/mm/vmstat.c b/mm/vmstat.c index d5cc8d739fac..27a94afd4ee5 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -2041,7 +2041,7 @@ static void __init init_cpu_node_state(void) int node; for_each_online_node(node) { - if (cpumask_weight(cpumask_of_node(node)) > 0) + if (!cpumask_empty(cpumask_of_node(node))) node_set_state(node, N_CPU); } } @@ -2068,7 +2068,7 @@ static int vmstat_cpu_dead(unsigned int cpu) refresh_zone_stat_thresholds(); node_cpus = cpumask_of_node(node); - if (cpumask_weight(node_cpus) > 0) + if (!cpumask_empty(node_cpus)) return 0; node_clear_state(node, N_CPU);
mm/vmstat.c code calls cpumask_weight() to check if any bit of a given cpumask is set. We can do it more efficiently with cpumask_empty() because cpumask_empty() stops traversing the cpumask as soon as it finds first set bit, while cpumask_weight() counts all bits unconditionally. Signed-off-by: Yury Norov <yury.norov@gmail.com> --- mm/vmstat.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)