diff options
| author | Robin Murphy <robin.murphy@arm.com> | 2021-12-03 12:44:51 +0100 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2021-12-14 13:09:27 +0100 |
| commit | 6190741c294d1cad15198d5d2f912868434fa492 (patch) | |
| tree | 78db0adfb86b525083a2331b975ab30c323c05ff /drivers/perf | |
| parent | perf/arm-cmn: Fix CPU hotplug unregistration (diff) | |
| download | linux-6190741c294d1cad15198d5d2f912868434fa492.tar.xz linux-6190741c294d1cad15198d5d2f912868434fa492.zip | |
perf/arm-cmn: Account for NUMA affinity
On a system with multiple CMN meshes, ideally we'd want to access each
PMU from within its own mesh, rather than with a long CML round-trip,
wherever feasible. Since such a system is likely to be presented as
multiple NUMA nodes, let's also hope a proximity domain is specified
for each CMN programming interface, and use that to guide our choice
of IRQ affinity to favour a node-local CPU where possible.
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Link: https://lore.kernel.org/r/32438b0d016e0649d882d47d30ac2000484287b9.1638530442.git.robin.murphy@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'drivers/perf')
| -rw-r--r-- | drivers/perf/arm-cmn.c | 51 |
1 files changed, 38 insertions, 13 deletions
diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c index 400eb7f579dc..02b898dbba91 100644 --- a/drivers/perf/arm-cmn.c +++ b/drivers/perf/arm-cmn.c @@ -1147,23 +1147,47 @@ static int arm_cmn_commit_txn(struct pmu *pmu) return 0; } -static int arm_cmn_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node) +static void arm_cmn_migrate(struct arm_cmn *cmn, unsigned int cpu) +{ + unsigned int i; + + perf_pmu_migrate_context(&cmn->pmu, cmn->cpu, cpu); + for (i = 0; i < cmn->num_dtcs; i++) + irq_set_affinity(cmn->dtc[i].irq, cpumask_of(cpu)); + cmn->cpu = cpu; +} + +static int arm_cmn_pmu_online_cpu(unsigned int cpu, struct hlist_node *cpuhp_node) { struct arm_cmn *cmn; - unsigned int i, target; + int node; - cmn = hlist_entry_safe(node, struct arm_cmn, cpuhp_node); - if (cpu != cmn->cpu) - return 0; + cmn = hlist_entry_safe(cpuhp_node, struct arm_cmn, cpuhp_node); + node = dev_to_node(cmn->dev); + if (node != NUMA_NO_NODE && cpu_to_node(cmn->cpu) != node && cpu_to_node(cpu) == node) + arm_cmn_migrate(cmn, cpu); + return 0; +} + +static int arm_cmn_pmu_offline_cpu(unsigned int cpu, struct hlist_node *cpuhp_node) +{ + struct arm_cmn *cmn; + unsigned int target; + int node; + cpumask_t mask; - target = cpumask_any_but(cpu_online_mask, cpu); - if (target >= nr_cpu_ids) + cmn = hlist_entry_safe(cpuhp_node, struct arm_cmn, cpuhp_node); + if (cpu != cmn->cpu) return 0; - perf_pmu_migrate_context(&cmn->pmu, cpu, target); - for (i = 0; i < cmn->num_dtcs; i++) - irq_set_affinity(cmn->dtc[i].irq, cpumask_of(target)); - cmn->cpu = target; + node = dev_to_node(cmn->dev); + if (cpumask_and(&mask, cpumask_of_node(node), cpu_online_mask) && + cpumask_andnot(&mask, &mask, cpumask_of(cpu))) + target = cpumask_any(&mask); + else + target = cpumask_any_but(cpu_online_mask, cpu); + if (target < nr_cpu_ids) + arm_cmn_migrate(cmn, target); return 0; } @@ -1532,7 +1556,7 @@ static int arm_cmn_probe(struct platform_device *pdev) if (err) return err; - cmn->cpu = raw_smp_processor_id(); + cmn->cpu = cpumask_local_spread(0, dev_to_node(cmn->dev)); cmn->pmu = (struct pmu) { .module = THIS_MODULE, .attr_groups = arm_cmn_attr_groups, @@ -1608,7 +1632,8 @@ static int __init arm_cmn_init(void) int ret; ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, - "perf/arm/cmn:online", NULL, + "perf/arm/cmn:online", + arm_cmn_pmu_online_cpu, arm_cmn_pmu_offline_cpu); if (ret < 0) return ret; |