diff options
Diffstat (limited to 'arch/arm/kernel/perf_event_cpu.c')
| -rw-r--r-- | arch/arm/kernel/perf_event_cpu.c | 71 |
1 files changed, 70 insertions, 1 deletions
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c index b2f202be922..e9d1995b002 100644 --- a/arch/arm/kernel/perf_event_cpu.c +++ b/arch/arm/kernel/perf_event_cpu.c @@ -30,9 +30,12 @@ #include <linux/slab.h> #include <linux/spinlock.h> +#include <asm/bL_switcher.h> #include <asm/cputype.h> #include <asm/irq_regs.h> #include <asm/pmu.h> +#include <asm/smp_plat.h> +#include <asm/topology.h> static LIST_HEAD(cpu_pmus_list); @@ -319,6 +322,33 @@ static void cpu_pmu_free(struct arm_pmu *pmu) kfree(pmu); } +/* + * HACK: Find a b.L switcher partner for CPU cpu on the specified cluster + * This information should be obtained from an interface provided by the + * Switcher itself, if possible. + */ +#ifdef CONFIG_BL_SWITCHER +static int bL_get_partner(int cpu, int cluster) +{ + unsigned int i; + + + for (i = 0; i < NR_CPUS; i++) { + if (cpu_topology[i].thread_id == cpu_topology[cpu].thread_id && + cpu_topology[i].core_id == cpu_topology[cpu].core_id && + cpu_topology[i].socket_id == cluster) + return i; + } + + return -1; /* no partner found */ +} +#else +static int bL_get_partner(int __always_unused cpu, int __always_unused cluster) +{ + return -1; +} +#endif + static int cpu_pmu_device_probe(struct platform_device *pdev) { const struct of_device_id *of_id; @@ -340,6 +370,7 @@ static int cpu_pmu_device_probe(struct platform_device *pdev) struct device_node *ncluster; int cluster = -1; cpumask_t sibling_mask; + unsigned int i; ncluster = of_parse_phandle(node, "cluster", 0); if (ncluster) { @@ -350,12 +381,50 @@ static int cpu_pmu_device_probe(struct platform_device *pdev) cluster = be32_to_cpup(hwid); } /* set sibling mask to all cpu mask if socket is not specified */ - if (cluster == -1 || + /* + * In a switcher kernel, we affine all PMUs to CPUs and + * abstract the runtime presence/absence of PMUs at a lower + * level. + */ + if (cluster == -1 || IS_ENABLED(CONFIG_BL_SWITCHER) || cluster_to_logical_mask(cluster, &sibling_mask)) cpumask_copy(&sibling_mask, cpu_possible_mask); + if (bL_switcher_get_enabled()) + /* + * The switcher initialises late now, so it should not + * have initialised yet: + */ + BUG(); + + /* + * HACK: Deduce how the switcher will modify the topology + * in order to fill in PMU<->CPU combinations which don't + * make sense when the switcher is disabled. Ideally, this + * knowledge should come from the swithcer somehow. + */ + for (i = 0; i < NR_CPUS; i++) { + int cpu = i; + + if (cpu_topology[i].socket_id != cluster) { + int partner = bL_get_partner(i, cluster); + + if (partner != -1) + cpu = partner; + } + + per_cpu_ptr(cpu_pmus, i)->mpidr = + cpu_logical_map(cpu); + } + + /* + * This relies on an MP view of the system to choose the right + * CPU to run init_fn: + */ smp_call_function_any(&sibling_mask, init_fn, pmu, 1); + bL_switcher_put_enabled(); + /* now set the valid_cpus after init */ cpumask_copy(&pmu->valid_cpus, &sibling_mask); } else { |