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| author |   Valentin Schneider <valentin.schneider@arm.com> | 2020-04-15 22:05:06 +0100 |
|---|---|---|
| committer |   Peter Zijlstra <peterz@infradead.org> | 2020-04-30 20:14:39 +0200 |
| commit | e669ac8ab952df2f07dee1e1efbf40647d6de332 (patch) | |
| tree | 19a14e3cb10525a7552d77d4927d531fe2d86dd3 /kernel/sched/topology.c | |
| parent | sched/debug: Make sd->flags sysctl read-only (diff) | |
| download | linux-e669ac8ab952df2f07dee1e1efbf40647d6de332.tar.xz linux-e669ac8ab952df2f07dee1e1efbf40647d6de332.zip | |
sched: Remove checks against SD_LOAD_BALANCE
The SD_LOAD_BALANCE flag is set unconditionally for all domains in
sd_init(). By making the sched_domain->flags syctl interface read-only, we
have removed the last piece of code that could clear that flag - as such,
it will now be always present. Rather than to keep carrying it along, we
can work towards getting rid of it entirely.
cpusets don't need it because they can make CPUs be attached to the NULL
domain (e.g. cpuset with sched_load_balance=0), or to a partitioned
root_domain, i.e. a sched_domain hierarchy that doesn't span the entire
system (e.g. root cpuset with sched_load_balance=0 and sibling cpusets with
sched_load_balance=1).
isolcpus apply the same "trick": isolated CPUs are explicitly taken out of
the sched_domain rebuild (using housekeeping_cpumask()), so they get the
NULL domain treatment as well.
Remove the checks against SD_LOAD_BALANCE.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200415210512.805-4-valentin.schneider@arm.com
Diffstat (limited to '')
| -rw-r--r-- | kernel/sched/topology.c | 28 |
1 files changed, 9 insertions, 19 deletions
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 8344757bba6e..a9dc34a0ebc1 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -33,14 +33,6 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, cpumask_clear(groupmask); printk(KERN_DEBUG "%*s domain-%d: ", level, "", level); - - if (!(sd->flags & SD_LOAD_BALANCE)) { - printk("does not load-balance\n"); - if (sd->parent) - printk(KERN_ERR "ERROR: !SD_LOAD_BALANCE domain has parent"); - return -1; - } - printk(KERN_CONT "span=%*pbl level=%s\n", cpumask_pr_args(sched_domain_span(sd)), sd->name); @@ -151,8 +143,7 @@ static int sd_degenerate(struct sched_domain *sd) return 1; /* Following flags need at least 2 groups */ - if (sd->flags & (SD_LOAD_BALANCE | - SD_BALANCE_NEWIDLE | + if (sd->flags & (SD_BALANCE_NEWIDLE | SD_BALANCE_FORK | SD_BALANCE_EXEC | SD_SHARE_CPUCAPACITY | @@ -183,15 +174,14 @@ sd_parent_degenerate(struct sched_domain *sd, struct sched_domain *parent) /* Flags needing groups don't count if only 1 group in parent */ if (parent->groups == parent->groups->next) { - pflags &= ~(SD_LOAD_BALANCE | - SD_BALANCE_NEWIDLE | - SD_BALANCE_FORK | - SD_BALANCE_EXEC | - SD_ASYM_CPUCAPACITY | - SD_SHARE_CPUCAPACITY | - SD_SHARE_PKG_RESOURCES | - SD_PREFER_SIBLING | - SD_SHARE_POWERDOMAIN); + pflags &= ~(SD_BALANCE_NEWIDLE | + SD_BALANCE_FORK | + SD_BALANCE_EXEC | + SD_ASYM_CPUCAPACITY | + SD_SHARE_CPUCAPACITY | + SD_SHARE_PKG_RESOURCES | + SD_PREFER_SIBLING | + SD_SHARE_POWERDOMAIN); if (nr_node_ids == 1) pflags &= ~SD_SERIALIZE; } |