diff options
| author | Peter Zijlstra <a.p.zijlstra@chello.nl> | 2009-09-01 10:34:32 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-09-04 10:09:53 +0200 |
| commit | f93e65c186ab3c05ce2068733ca10e34fd00125e (patch) | |
| tree | 0e42dc647e8f24fd5abc0be7ef3d9a4fc58a2069 | |
| parent | 9aa55fbd01779a0b476d87cd9b5170fd5bebab1d (diff) | |
sched: Restore __cpu_power to a straight sum of power
cpu_power is supposed to be a representation of the process
capacity of the cpu, not a value to randomly tweak in order to
affect placement.
Remove the placement hacks.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Acked-by: Gautham R Shenoy <ego@in.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
LKML-Reference: <20090901083825.810860576@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | kernel/sched.c | 28 |
1 files changed, 12 insertions, 16 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index da1edc8277d..584a122b553 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -8464,15 +8464,13 @@ static void free_sched_groups(const struct cpumask *cpu_map, * there are asymmetries in the topology. If there are asymmetries, group * having more cpu_power will pickup more load compared to the group having * less cpu_power. - * - * cpu_power will be a multiple of SCHED_LOAD_SCALE. This multiple represents - * the maximum number of tasks a group can handle in the presence of other idle - * or lightly loaded groups in the same sched domain. */ static void init_sched_groups_power(int cpu, struct sched_domain *sd) { struct sched_domain *child; struct sched_group *group; + long power; + int weight; WARN_ON(!sd || !sd->groups); @@ -8483,22 +8481,20 @@ static void init_sched_groups_power(int cpu, struct sched_domain *sd) sd->groups->__cpu_power = 0; - /* - * For perf policy, if the groups in child domain share resources - * (for example cores sharing some portions of the cache hierarchy - * or SMT), then set this domain groups cpu_power such that each group - * can handle only one task, when there are other idle groups in the - * same sched domain. - */ - if (!child || (!(sd->flags & SD_POWERSAVINGS_BALANCE) && - (child->flags & - (SD_SHARE_CPUPOWER | SD_SHARE_PKG_RESOURCES)))) { - sg_inc_cpu_power(sd->groups, SCHED_LOAD_SCALE); + if (!child) { + power = SCHED_LOAD_SCALE; + weight = cpumask_weight(sched_domain_span(sd)); + /* + * SMT siblings share the power of a single core. + */ + if ((sd->flags & SD_SHARE_CPUPOWER) && weight > 1) + power /= weight; + sg_inc_cpu_power(sd->groups, power); return; } /* - * add cpu_power of each child group to this groups cpu_power + * Add cpu_power of each child group to this groups cpu_power. */ group = child->groups; do { |