[RFT PATCH v1 3/4] cpu-topology: Move cpu topology code to common code.

Atish Patra
2018-11-29T23:28:36Z

Both RISC-V & ARM64 are using cpu-map device tree to describe
their cpu topology. It's better to move the relevant code to
a common place instead of duplicate code.

Signed-off-by: Atish Patra <atish.patra@wdc.com>
---
arch/arm64/include/asm/topology.h | 22 ---
arch/arm64/kernel/topology.c | 303 +-------------------------------------
drivers/base/arch_topology.c | 294 ++++++++++++++++++++++++++++++++++++
include/linux/arch_topology.h | 26 ++++
include/linux/topology.h | 1 +
5 files changed, 325 insertions(+), 321 deletions(-)

diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h
index 0524f243..b1b61e0f 100644
--- a/arch/arm64/include/asm/topology.h
+++ b/arch/arm64/include/asm/topology.h
@@ -4,29 +4,7 @@

#include <linux/cpumask.h>

-struct cpu_topology {
- int thread_id;
- int core_id;
- int package_id;
- int llc_id;
- cpumask_t thread_sibling;
- cpumask_t core_sibling;
- cpumask_t llc_sibling;
-};
-
-extern struct cpu_topology cpu_topology[NR_CPUS];
-
-#define topology_physical_package_id(cpu) (cpu_topology[cpu].package_id)
-#define topology_core_id(cpu) (cpu_topology[cpu].core_id)
-#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling)
-#define topology_sibling_cpumask(cpu) (&cpu_topology[cpu].thread_sibling)
-#define topology_llc_cpumask(cpu) (&cpu_topology[cpu].llc_sibling)
-
-void init_cpu_topology(void);
void store_cpu_topology(unsigned int cpuid);
-void remove_cpu_topology(unsigned int cpuid);
-const struct cpumask *cpu_coregroup_mask(int cpu);
-
#ifdef CONFIG_NUMA

struct pci_bus;
diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index 0825c4a8..6b95c91e 100644
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -14,250 +14,13 @@
#include <linux/acpi.h>
#include <linux/arch_topology.h>
#include <linux/cacheinfo.h>
-#include <linux/cpu.h>
-#include <linux/cpumask.h>
#include <linux/init.h>
#include <linux/percpu.h>
-#include <linux/node.h>
-#include <linux/nodemask.h>
-#include <linux/of.h>
-#include <linux/sched.h>
-#include <linux/sched/topology.h>
-#include <linux/slab.h>
-#include <linux/smp.h>
-#include <linux/string.h>

#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/topology.h>

-static int __init get_cpu_for_node(struct device_node *node)
-{
- struct device_node *cpu_node;
- int cpu;
-
- cpu_node = of_parse_phandle(node, "cpu", 0);
- if (!cpu_node)
- return -1;
-
- cpu = of_cpu_node_to_id(cpu_node);
- if (cpu >= 0)
- topology_parse_cpu_capacity(cpu_node, cpu);
- else
- pr_crit("Unable to find CPU node for %pOF\n", cpu_node);
-
- of_node_put(cpu_node);
- return cpu;
-}
-
-static int __init parse_core(struct device_node *core, int package_id,
- int core_id)
-{
- char name[10];
- bool leaf = true;
- int i = 0;
- int cpu;
- struct device_node *t;
-
- do {
- snprintf(name, sizeof(name), "thread%d", i);
- t = of_get_child_by_name(core, name);
- if (t) {
- leaf = false;
- cpu = get_cpu_for_node(t);
- if (cpu >= 0) {
- cpu_topology[cpu].package_id = package_id;
- cpu_topology[cpu].core_id = core_id;
- cpu_topology[cpu].thread_id = i;
- } else {
- pr_err("%pOF: Can't get CPU for thread\n",
- t);
- of_node_put(t);
- return -EINVAL;
- }
- of_node_put(t);
- }
- i++;
- } while (t);
-
- cpu = get_cpu_for_node(core);
- if (cpu >= 0) {
- if (!leaf) {
- pr_err("%pOF: Core has both threads and CPU\n",
- core);
- return -EINVAL;
- }
-
- cpu_topology[cpu].package_id = package_id;
- cpu_topology[cpu].core_id = core_id;
- } else if (leaf) {
- pr_err("%pOF: Can't get CPU for leaf core\n", core);
- return -EINVAL;
- }
-
- return 0;
-}
-
-static int __init parse_cluster(struct device_node *cluster, int depth)
-{
- char name[10];
- bool leaf = true;
- bool has_cores = false;
- struct device_node *c;
- static int package_id __initdata;
- int core_id = 0;
- int i, ret;
-
- /*
- * First check for child clusters; we currently ignore any
- * information about the nesting of clusters and present the
- * scheduler with a flat list of them.
- */
- i = 0;
- do {
- snprintf(name, sizeof(name), "cluster%d", i);
- c = of_get_child_by_name(cluster, name);
- if (c) {
- leaf = false;
- ret = parse_cluster(c, depth + 1);
- of_node_put(c);
- if (ret != 0)
- return ret;
- }
- i++;
- } while (c);
-
- /* Now check for cores */
- i = 0;
- do {
- snprintf(name, sizeof(name), "core%d", i);
- c = of_get_child_by_name(cluster, name);
- if (c) {
- has_cores = true;
-
- if (depth == 0) {
- pr_err("%pOF: cpu-map children should be clusters\n",
- c);
- of_node_put(c);
- return -EINVAL;
- }
-
- if (leaf) {
- ret = parse_core(c, package_id, core_id++);
- } else {
- pr_err("%pOF: Non-leaf cluster with core %s\n",
- cluster, name);
- ret = -EINVAL;
- }
-
- of_node_put(c);
- if (ret != 0)
- return ret;
- }
- i++;
- } while (c);
-
- if (leaf && !has_cores)
- pr_warn("%pOF: empty cluster\n", cluster);
-
- if (leaf)
- package_id++;
-
- return 0;
-}
-
-static int __init parse_dt_topology(void)
-{
- struct device_node *cn, *map;
- int ret = 0;
- int cpu;
-
- cn = of_find_node_by_path("/cpus");
- if (!cn) {
- pr_err("No CPU information found in DT\n");
- return 0;
- }
-
- /*
- * When topology is provided cpu-map is essentially a root
- * cluster with restricted subnodes.
- */
- map = of_get_child_by_name(cn, "cpu-map");
- if (!map)
- goto out;
-
- ret = parse_cluster(map, 0);
- if (ret != 0)
- goto out_map;
-
- topology_normalize_cpu_scale();
-
- /*
- * Check that all cores are in the topology; the SMP code will
- * only mark cores described in the DT as possible.
- */
- for_each_possible_cpu(cpu)
- if (cpu_topology[cpu].package_id == -1)
- ret = -EINVAL;
-
-out_map:
- of_node_put(map);
-out:
- of_node_put(cn);
- return ret;
-}
-
-/*
- * cpu topology table
- */
-struct cpu_topology cpu_topology[NR_CPUS];
-EXPORT_SYMBOL_GPL(cpu_topology);
-
-const struct cpumask *cpu_coregroup_mask(int cpu)
-{
- const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));
-
- /* Find the smaller of NUMA, core or LLC siblings */
- if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
- /* not numa in package, lets use the package siblings */
- core_mask = &cpu_topology[cpu].core_sibling;
- }
- if (cpu_topology[cpu].llc_id != -1) {
- if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
- core_mask = &cpu_topology[cpu].llc_sibling;
- }
-
- return core_mask;
-}
-
-static void update_siblings_masks(unsigned int cpuid)
-{
- struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
- int cpu;
-
- /* update core and thread sibling masks */
- for_each_online_cpu(cpu) {
- cpu_topo = &cpu_topology[cpu];
-
- if (cpuid_topo->llc_id == cpu_topo->llc_id) {
- cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
- cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
- }
-
- if (cpuid_topo->package_id != cpu_topo->package_id)
- continue;
-
- cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
- cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
-
- if (cpuid_topo->core_id != cpu_topo->core_id)
- continue;
-
- cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
- cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
- }
-}
-
void store_cpu_topology(unsigned int cpuid)
{
struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
@@ -296,59 +59,19 @@ void store_cpu_topology(unsigned int cpuid)
update_siblings_masks(cpuid);
}

-static void clear_cpu_topology(int cpu)
-{
- struct cpu_topology *cpu_topo = &cpu_topology[cpu];
-
- cpumask_clear(&cpu_topo->llc_sibling);
- cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);
-
- cpumask_clear(&cpu_topo->core_sibling);
- cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
- cpumask_clear(&cpu_topo->thread_sibling);
- cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
-}
-
-static void __init reset_cpu_topology(void)
-{
- unsigned int cpu;
-
- for_each_possible_cpu(cpu) {
- struct cpu_topology *cpu_topo = &cpu_topology[cpu];
-
- cpu_topo->thread_id = -1;
- cpu_topo->core_id = 0;
- cpu_topo->package_id = -1;
- cpu_topo->llc_id = -1;
-
- clear_cpu_topology(cpu);
- }
-}
-
-void remove_cpu_topology(unsigned int cpu)
-{
- int sibling;
-
- for_each_cpu(sibling, topology_core_cpumask(cpu))
- cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
- for_each_cpu(sibling, topology_sibling_cpumask(cpu))
- cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
- for_each_cpu(sibling, topology_llc_cpumask(cpu))
- cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));
-
- clear_cpu_topology(cpu);
-}
-
#ifdef CONFIG_ACPI
/*
* Propagate the topology information of the processor_topology_node tree to the
* cpu_topology array.
*/
-static int __init parse_acpi_topology(void)
+int __init parse_acpi_topology(void)
{
bool is_threaded;
int cpu, topology_id;

+ if (acpi_disabled)
+ return 0;
+
is_threaded = read_cpuid_mpidr() & MPIDR_MT_BITMASK;

for_each_possible_cpu(cpu) {
@@ -384,24 +107,6 @@ static int __init parse_acpi_topology(void)

return 0;
}
-
-#else
-static inline int __init parse_acpi_topology(void)
-{
- return -EINVAL;
-}
#endif

-void __init init_cpu_topology(void)
-{
- reset_cpu_topology();

- /*
- * Discard anything that was parsed if we hit an error so we
- * don't use partial information.
- */
- if (!acpi_disabled && parse_acpi_topology())
- reset_cpu_topology();
- else if (of_have_populated_dt() && parse_dt_topology())
- reset_cpu_topology();
-}
diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
index edfcf8d9..abddcb3d 100644
--- a/drivers/base/arch_topology.c
+++ b/drivers/base/arch_topology.c
@@ -16,6 +16,11 @@
#include <linux/string.h>
#include <linux/sched/topology.h>
#include <linux/cpuset.h>
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/percpu.h>
+#include <linux/sched.h>
+#include <linux/smp.h>

DEFINE_PER_CPU(unsigned long, freq_scale) = SCHED_CAPACITY_SCALE;

@@ -278,3 +283,292 @@ static void parsing_done_workfn(struct work_struct *work)
#else
core_initcall(free_raw_capacity);
#endif
+
+static int __init get_cpu_for_node(struct device_node *node)
+{
+ struct device_node *cpu_node;
+ int cpu;
+
+ cpu_node = of_parse_phandle(node, "cpu", 0);
+ if (!cpu_node)
+ return -1;
+
+ cpu = of_cpu_node_to_id(cpu_node);
+ if (cpu >= 0)
+ topology_parse_cpu_capacity(cpu_node, cpu);
+ else
+ pr_crit("Unable to find CPU node for %pOF\n", cpu_node);
+
+ of_node_put(cpu_node);
+ return cpu;
+}
+
+static int __init parse_core(struct device_node *core, int package_id,
+ int core_id)
+{
+ char name[10];
+ bool leaf = true;
+ int i = 0;
+ int cpu;
+ struct device_node *t;
+
+ do {
+ snprintf(name, sizeof(name), "thread%d", i);
+ t = of_get_child_by_name(core, name);
+ if (t) {
+ leaf = false;
+ cpu = get_cpu_for_node(t);
+ if (cpu >= 0) {
+ cpu_topology[cpu].package_id = package_id;
+ cpu_topology[cpu].core_id = core_id;
+ cpu_topology[cpu].thread_id = i;
+ } else {
+ pr_err("%pOF: Can't get CPU for thread\n",
+ t);
+ of_node_put(t);
+ return -EINVAL;
+ }
+ of_node_put(t);
+ }
+ i++;
+ } while (t);
+
+ cpu = get_cpu_for_node(core);
+ if (cpu >= 0) {
+ if (!leaf) {
+ pr_err("%pOF: Core has both threads and CPU\n",
+ core);
+ return -EINVAL;
+ }
+
+ cpu_topology[cpu].package_id = package_id;
+ cpu_topology[cpu].core_id = core_id;
+ } else if (leaf) {
+ pr_err("%pOF: Can't get CPU for leaf core\n", core);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __init parse_cluster(struct device_node *cluster, int depth)
+{
+ char name[10];
+ bool leaf = true;
+ bool has_cores = false;
+ int core_id = 0;
+ int i, ret;
+ struct device_node *c;
+ static int package_id __initdata;
+
+ /*
+ * First check for child clusters; we currently ignore any
+ * information about the nesting of clusters and present the
+ * scheduler with a flat list of them.
+ */
+ i = 0;
+ do {
+ snprintf(name, sizeof(name), "cluster%d", i);
+ c = of_get_child_by_name(cluster, name);
+ if (c) {
+ leaf = false;
+ ret = parse_cluster(c, depth + 1);
+ of_node_put(c);
+ if (ret != 0)
+ return ret;
+ }
+ i++;
+ } while (c);
+
+ /* Now check for cores */
+ i = 0;
+ do {
+ snprintf(name, sizeof(name), "core%d", i);
+ c = of_get_child_by_name(cluster, name);
+ if (c) {
+ has_cores = true;
+
+ if (depth == 0) {
+ pr_err("%pOF: cpu-map children should be clusters\n",
+ c);
+ of_node_put(c);
+ return -EINVAL;
+ }
+
+ if (leaf) {
+ ret = parse_core(c, package_id, core_id++);
+ } else {
+ pr_err("%pOF: Non-leaf cluster with core %s\n",
+ cluster, name);
+ ret = -EINVAL;
+ }
+
+ of_node_put(c);
+ if (ret != 0)
+ return ret;
+ }
+ i++;
+ } while (c);
+
+ if (leaf && !has_cores)
+ pr_warn("%pOF: empty cluster\n", cluster);
+
+ if (leaf)
+ package_id++;
+
+ return 0;
+}
+
+static int __init parse_dt_topology(void)
+{
+ struct device_node *cn, *map;
+ int ret = 0;
+ int cpu;
+
+ cn = of_find_node_by_path("/cpus");
+ if (!cn) {
+ pr_err("No CPU information found in DT\n");
+ return 0;
+ }
+
+ /*
+ * When topology is provided cpu-map is essentially a root
+ * cluster with restricted subnodes.
+ */
+ map = of_get_child_by_name(cn, "cpu-map");
+ if (!map)
+ goto out;
+
+ ret = parse_cluster(map, 0);
+ if (ret != 0)
+ goto out_map;
+
+ topology_normalize_cpu_scale();
+
+ /*
+ * Check that all cores are in the topology; the SMP code will
+ * only mark cores described in the DT as possible.
+ */
+ for_each_possible_cpu(cpu)
+ if (cpu_topology[cpu].package_id == -1)
+ ret = -EINVAL;
+
+out_map:
+ of_node_put(map);
+out:
+ of_node_put(cn);
+ return ret;
+}
+
+/*
+ * cpu topology table
+ */
+struct cpu_topology cpu_topology[NR_CPUS];
+EXPORT_SYMBOL_GPL(cpu_topology);
+
+const struct cpumask *cpu_coregroup_mask(int cpu)
+{
+ const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu));
+
+ /* Find the smaller of NUMA, core or LLC siblings */
+ if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) {
+ /* not numa in package, lets use the package siblings */
+ core_mask = &cpu_topology[cpu].core_sibling;
+ }
+ if (cpu_topology[cpu].llc_id != -1) {
+ if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask))
+ core_mask = &cpu_topology[cpu].llc_sibling;
+ }
+
+ return core_mask;
+}
+
+void update_siblings_masks(unsigned int cpuid)
+{
+ struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
+ int cpu;
+
+ /* update core and thread sibling masks */
+ for_each_online_cpu(cpu) {
+ cpu_topo = &cpu_topology[cpu];
+
+ if (cpuid_topo->llc_id == cpu_topo->llc_id) {
+ cpumask_set_cpu(cpu, &cpuid_topo->llc_sibling);
+ cpumask_set_cpu(cpuid, &cpu_topo->llc_sibling);
+ }
+
+ if (cpuid_topo->package_id != cpu_topo->package_id)
+ continue;
+
+ cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
+ cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
+
+ if (cpuid_topo->core_id != cpu_topo->core_id)
+ continue;
+
+ cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
+ cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
+ }
+}
+
+static void clear_cpu_topology(int cpu)
+{
+ struct cpu_topology *cpu_topo = &cpu_topology[cpu];
+
+ cpumask_clear(&cpu_topo->llc_sibling);
+ cpumask_set_cpu(cpu, &cpu_topo->llc_sibling);
+
+ cpumask_clear(&cpu_topo->core_sibling);
+ cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
+ cpumask_clear(&cpu_topo->thread_sibling);
+ cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
+}
+
+static void __init reset_cpu_topology(void)
+{
+ unsigned int cpu;
+
+ for_each_possible_cpu(cpu) {
+ struct cpu_topology *cpu_topo = &cpu_topology[cpu];
+
+ cpu_topo->thread_id = -1;
+ cpu_topo->core_id = 0;
+ cpu_topo->package_id = -1;
+ cpu_topo->llc_id = -1;
+
+ clear_cpu_topology(cpu);
+ }
+}
+
+void remove_cpu_topology(unsigned int cpu)
+{
+ int sibling;
+
+ for_each_cpu(sibling, topology_core_cpumask(cpu))
+ cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
+ for_each_cpu(sibling, topology_sibling_cpumask(cpu))
+ cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
+ for_each_cpu(sibling, topology_llc_cpumask(cpu))
+ cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));
+
+ clear_cpu_topology(cpu);
+}
+
+__weak int __init parse_acpi_topology(void)
+{
+ return 0;
+}
+
+void __init init_cpu_topology(void)
+{
+ reset_cpu_topology();
+
+ /*
+ * Discard anything that was parsed if we hit an error so we
+ * don't use partial information.
+ */
+ if (parse_acpi_topology())
+ reset_cpu_topology();
+ else if (of_have_populated_dt() && parse_dt_topology())
+ reset_cpu_topology();
+}
diff --git a/include/linux/arch_topology.h b/include/linux/arch_topology.h
index d9bdc1a7..167e9dd6 100644
--- a/include/linux/arch_topology.h
+++ b/include/linux/arch_topology.h
@@ -33,4 +33,30 @@ unsigned long topology_get_freq_scale(int cpu)
return per_cpu(freq_scale, cpu);
}

+struct cpu_topology {
+ int thread_id;
+ int core_id;
+ int package_id;
+ int llc_id;
+ cpumask_t thread_sibling;
+ cpumask_t core_sibling;
+ cpumask_t llc_sibling;
+};
+
+#ifdef CONFIG_GENERIC_ARCH_TOPOLOGY
+extern struct cpu_topology cpu_topology[NR_CPUS];
+
+#define topology_physical_package_id(cpu) (cpu_topology[cpu].package_id)
+#define topology_core_id(cpu) (cpu_topology[cpu].core_id)
+#define topology_core_cpumask(cpu) (&cpu_topology[cpu].core_sibling)
+#define topology_sibling_cpumask(cpu) (&cpu_topology[cpu].thread_sibling)
+#define topology_llc_cpumask(cpu) (&cpu_topology[cpu].llc_sibling)
+
+#endif
+
+void init_cpu_topology(void);
+void update_siblings_masks(unsigned int cpu);
+void remove_cpu_topology(unsigned int cpuid);
+const struct cpumask *cpu_coregroup_mask(int cpu);
+
#endif /* _LINUX_ARCH_TOPOLOGY_H_ */
diff --git a/include/linux/topology.h b/include/linux/topology.h
index cb0775e1..81501fac 100644
--- a/include/linux/topology.h
+++ b/include/linux/topology.h
@@ -32,6 +32,7 @@
#include <linux/mmzone.h>
#include <linux/smp.h>
#include <linux/percpu.h>
+#include <linux/arch_topology.h>
#include <asm/topology.h>

#ifndef nr_cpus_node
--
2.7.4