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author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2020-05-12 12:18:21 -0700 |
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committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2020-05-12 12:18:21 -0700 |
commit | 0fdc50dfab47d525b71a9f0d8310746cdc0c09c5 (patch) | |
tree | 42f5f09f2c8677389136541815394b76fba07600 /kernel/sched/topology.c | |
parent | Input: add driver for the Cypress CY8CTMA140 touchscreen (diff) | |
parent | Linux 5.6 (diff) | |
download | linux-dev-0fdc50dfab47d525b71a9f0d8310746cdc0c09c5.tar.xz linux-dev-0fdc50dfab47d525b71a9f0d8310746cdc0c09c5.zip |
Merge tag 'v5.6' into next
Sync up with mainline to get device tree and other changes.
Diffstat (limited to 'kernel/sched/topology.c')
-rw-r--r-- | kernel/sched/topology.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 6ec1e595b1d4..dfb64c08a407 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -1880,6 +1880,42 @@ static struct sched_domain *build_sched_domain(struct sched_domain_topology_leve } /* + * Ensure topology masks are sane, i.e. there are no conflicts (overlaps) for + * any two given CPUs at this (non-NUMA) topology level. + */ +static bool topology_span_sane(struct sched_domain_topology_level *tl, + const struct cpumask *cpu_map, int cpu) +{ + int i; + + /* NUMA levels are allowed to overlap */ + if (tl->flags & SDTL_OVERLAP) + return true; + + /* + * Non-NUMA levels cannot partially overlap - they must be either + * completely equal or completely disjoint. Otherwise we can end up + * breaking the sched_group lists - i.e. a later get_group() pass + * breaks the linking done for an earlier span. + */ + for_each_cpu(i, cpu_map) { + if (i == cpu) + continue; + /* + * We should 'and' all those masks with 'cpu_map' to exactly + * match the topology we're about to build, but that can only + * remove CPUs, which only lessens our ability to detect + * overlaps + */ + if (!cpumask_equal(tl->mask(cpu), tl->mask(i)) && + cpumask_intersects(tl->mask(cpu), tl->mask(i))) + return false; + } + + return true; +} + +/* * Find the sched_domain_topology_level where all CPU capacities are visible * for all CPUs. */ @@ -1975,6 +2011,9 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att has_asym = true; } + if (WARN_ON(!topology_span_sane(tl, cpu_map, i))) + goto error; + sd = build_sched_domain(tl, cpu_map, attr, sd, dflags, i); if (tl == sched_domain_topology) |