On 06.07.19 19:22, Srikar Dronamraju wrote: > * Markus Elfring <Markus.Elfring@xxxxxx> [2019-07-06 16:05:17]: > >> From: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> >> Date: Sat, 6 Jul 2019 16:00:13 +0200 >> >> Avoid an extra function call by using a ternary operator instead of >> a conditional statement. >> >> This issue was detected by using the Coccinelle software. >> >> Signed-off-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx> >> --- >> kernel/sched/topology.c | 6 +----- >> 1 file changed, 1 insertion(+), 5 deletions(-) >> >> diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c >> index f751ce0b783e..6190eb52c30a 100644 >> --- a/kernel/sched/topology.c >> +++ b/kernel/sched/topology.c >> @@ -886,11 +886,7 @@ build_group_from_child_sched_domain(struct sched_domain *sd, int cpu) >> return NULL; >> >> sg_span = sched_group_span(sg); >> - if (sd->child) >> - cpumask_copy(sg_span, sched_domain_span(sd->child)); >> - else >> - cpumask_copy(sg_span, sched_domain_span(sd)); >> - >> + cpumask_copy(sg_span, sched_domain_span(sd->child ? sd->child : sd)); > > At runtime, Are we avoiding a function call? > However I think we are avoiding a branch instead of a conditional, which may > be beneficial. If you're assuming the compiler doesn't already optimize that (no idea whether gcc really does that). @Markus: could you check what gcc is actually generating out of both the old and your new version ? --mtx -- Enrico Weigelt, metux IT consult Free software and Linux embedded engineering info@xxxxxxxxx -- +49-151-27565287
