| Message ID | d226c91fed3dfa2dca644d14c88b1d1ff9d2e722.1370344689.git.viresh.kumar@linaro.org |
|---|---|
| State | Accepted |
| Headers | show |
Hi, Viresh On 06/04/2013 07:20 PM, Viresh Kumar wrote: [snip] > diff --git a/kernel/sched/core.c b/kernel/sched/core.c > index 58453b8..638f6cb 100644 > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, > sd = NULL; > for (tl = sched_domain_topology; tl->init; tl++) { > sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); > + if (!*per_cpu_ptr(d.sd, i)) What about: if (tl == sched_domain_topology) It cost less than per_cpu_ptr(), isn't it? Regards, Michael Wang > + *per_cpu_ptr(d.sd, i) = sd; > if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP)) > sd->flags |= SD_OVERLAP; > if (cpumask_equal(cpu_map, sched_domain_span(sd))) > break; > } > - > - while (sd->child) > - sd = sd->child; > - > - *per_cpu_ptr(d.sd, i) = sd; > } > > /* Build the groups for the domains */ >
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 58453b8..638f6cb 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6533,16 +6533,13 @@ static int build_sched_domains(const struct cpumask *cpu_map, sd = NULL; for (tl = sched_domain_topology; tl->init; tl++) { sd = build_sched_domain(tl, &d, cpu_map, attr, sd, i); + if (!*per_cpu_ptr(d.sd, i)) + *per_cpu_ptr(d.sd, i) = sd; if (tl->flags & SDTL_OVERLAP || sched_feat(FORCE_SD_OVERLAP)) sd->flags |= SD_OVERLAP; if (cpumask_equal(cpu_map, sched_domain_span(sd))) break; } - - while (sd->child) - sd = sd->child; - - *per_cpu_ptr(d.sd, i) = sd; } /* Build the groups for the domains */
We are saving first scheduling domain for a cpu in build_sched_domains() by iterating over the nested sd->child list. We don't actually need to do it this way. *per_cpu_ptr(d.sd, i) is guaranteed to be NULL in the beginning as we have called __visit_domain_allocation_hell() which does a memset to zero for struct s_data. So, save pointer to first SD while running the iteration loop over tl's. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> --- kernel/sched/core.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-)