summaryrefslogtreecommitdiffstats
path: root/tools/lib/perf/cpumap.c
diff options
context:
space:
mode:
Diffstat (limited to 'tools/lib/perf/cpumap.c')
-rw-r--r--tools/lib/perf/cpumap.c392
1 files changed, 392 insertions, 0 deletions
diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
new file mode 100644
index 000000000..6cd0be7c1
--- /dev/null
+++ b/tools/lib/perf/cpumap.c
@@ -0,0 +1,392 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <perf/cpumap.h>
+#include <stdlib.h>
+#include <linux/refcount.h>
+#include <internal/cpumap.h>
+#include <asm/bug.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <limits.h>
+
+static struct perf_cpu_map *perf_cpu_map__alloc(int nr_cpus)
+{
+ struct perf_cpu_map *cpus = malloc(sizeof(*cpus) + sizeof(struct perf_cpu) * nr_cpus);
+
+ if (cpus != NULL) {
+ cpus->nr = nr_cpus;
+ refcount_set(&cpus->refcnt, 1);
+
+ }
+ return cpus;
+}
+
+struct perf_cpu_map *perf_cpu_map__dummy_new(void)
+{
+ struct perf_cpu_map *cpus = perf_cpu_map__alloc(1);
+
+ if (cpus)
+ cpus->map[0].cpu = -1;
+
+ return cpus;
+}
+
+static void cpu_map__delete(struct perf_cpu_map *map)
+{
+ if (map) {
+ WARN_ONCE(refcount_read(&map->refcnt) != 0,
+ "cpu_map refcnt unbalanced\n");
+ free(map);
+ }
+}
+
+struct perf_cpu_map *perf_cpu_map__get(struct perf_cpu_map *map)
+{
+ if (map)
+ refcount_inc(&map->refcnt);
+ return map;
+}
+
+void perf_cpu_map__put(struct perf_cpu_map *map)
+{
+ if (map && refcount_dec_and_test(&map->refcnt))
+ cpu_map__delete(map);
+}
+
+static struct perf_cpu_map *cpu_map__default_new(void)
+{
+ struct perf_cpu_map *cpus;
+ int nr_cpus;
+
+ nr_cpus = sysconf(_SC_NPROCESSORS_ONLN);
+ if (nr_cpus < 0)
+ return NULL;
+
+ cpus = perf_cpu_map__alloc(nr_cpus);
+ if (cpus != NULL) {
+ int i;
+
+ for (i = 0; i < nr_cpus; ++i)
+ cpus->map[i].cpu = i;
+ }
+
+ return cpus;
+}
+
+struct perf_cpu_map *perf_cpu_map__default_new(void)
+{
+ return cpu_map__default_new();
+}
+
+
+static int cmp_cpu(const void *a, const void *b)
+{
+ const struct perf_cpu *cpu_a = a, *cpu_b = b;
+
+ return cpu_a->cpu - cpu_b->cpu;
+}
+
+static struct perf_cpu_map *cpu_map__trim_new(int nr_cpus, const struct perf_cpu *tmp_cpus)
+{
+ size_t payload_size = nr_cpus * sizeof(struct perf_cpu);
+ struct perf_cpu_map *cpus = perf_cpu_map__alloc(nr_cpus);
+ int i, j;
+
+ if (cpus != NULL) {
+ memcpy(cpus->map, tmp_cpus, payload_size);
+ qsort(cpus->map, nr_cpus, sizeof(struct perf_cpu), cmp_cpu);
+ /* Remove dups */
+ j = 0;
+ for (i = 0; i < nr_cpus; i++) {
+ if (i == 0 || cpus->map[i].cpu != cpus->map[i - 1].cpu)
+ cpus->map[j++].cpu = cpus->map[i].cpu;
+ }
+ cpus->nr = j;
+ assert(j <= nr_cpus);
+ }
+ return cpus;
+}
+
+struct perf_cpu_map *perf_cpu_map__read(FILE *file)
+{
+ struct perf_cpu_map *cpus = NULL;
+ int nr_cpus = 0;
+ struct perf_cpu *tmp_cpus = NULL, *tmp;
+ int max_entries = 0;
+ int n, cpu, prev;
+ char sep;
+
+ sep = 0;
+ prev = -1;
+ for (;;) {
+ n = fscanf(file, "%u%c", &cpu, &sep);
+ if (n <= 0)
+ break;
+ if (prev >= 0) {
+ int new_max = nr_cpus + cpu - prev - 1;
+
+ WARN_ONCE(new_max >= MAX_NR_CPUS, "Perf can support %d CPUs. "
+ "Consider raising MAX_NR_CPUS\n", MAX_NR_CPUS);
+
+ if (new_max >= max_entries) {
+ max_entries = new_max + MAX_NR_CPUS / 2;
+ tmp = realloc(tmp_cpus, max_entries * sizeof(struct perf_cpu));
+ if (tmp == NULL)
+ goto out_free_tmp;
+ tmp_cpus = tmp;
+ }
+
+ while (++prev < cpu)
+ tmp_cpus[nr_cpus++].cpu = prev;
+ }
+ if (nr_cpus == max_entries) {
+ max_entries += MAX_NR_CPUS;
+ tmp = realloc(tmp_cpus, max_entries * sizeof(struct perf_cpu));
+ if (tmp == NULL)
+ goto out_free_tmp;
+ tmp_cpus = tmp;
+ }
+
+ tmp_cpus[nr_cpus++].cpu = cpu;
+ if (n == 2 && sep == '-')
+ prev = cpu;
+ else
+ prev = -1;
+ if (n == 1 || sep == '\n')
+ break;
+ }
+
+ if (nr_cpus > 0)
+ cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
+ else
+ cpus = cpu_map__default_new();
+out_free_tmp:
+ free(tmp_cpus);
+ return cpus;
+}
+
+static struct perf_cpu_map *cpu_map__read_all_cpu_map(void)
+{
+ struct perf_cpu_map *cpus = NULL;
+ FILE *onlnf;
+
+ onlnf = fopen("/sys/devices/system/cpu/online", "r");
+ if (!onlnf)
+ return cpu_map__default_new();
+
+ cpus = perf_cpu_map__read(onlnf);
+ fclose(onlnf);
+ return cpus;
+}
+
+struct perf_cpu_map *perf_cpu_map__new(const char *cpu_list)
+{
+ struct perf_cpu_map *cpus = NULL;
+ unsigned long start_cpu, end_cpu = 0;
+ char *p = NULL;
+ int i, nr_cpus = 0;
+ struct perf_cpu *tmp_cpus = NULL, *tmp;
+ int max_entries = 0;
+
+ if (!cpu_list)
+ return cpu_map__read_all_cpu_map();
+
+ /*
+ * must handle the case of empty cpumap to cover
+ * TOPOLOGY header for NUMA nodes with no CPU
+ * ( e.g., because of CPU hotplug)
+ */
+ if (!isdigit(*cpu_list) && *cpu_list != '\0')
+ goto out;
+
+ while (isdigit(*cpu_list)) {
+ p = NULL;
+ start_cpu = strtoul(cpu_list, &p, 0);
+ if (start_cpu >= INT_MAX
+ || (*p != '\0' && *p != ',' && *p != '-'))
+ goto invalid;
+
+ if (*p == '-') {
+ cpu_list = ++p;
+ p = NULL;
+ end_cpu = strtoul(cpu_list, &p, 0);
+
+ if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
+ goto invalid;
+
+ if (end_cpu < start_cpu)
+ goto invalid;
+ } else {
+ end_cpu = start_cpu;
+ }
+
+ WARN_ONCE(end_cpu >= MAX_NR_CPUS, "Perf can support %d CPUs. "
+ "Consider raising MAX_NR_CPUS\n", MAX_NR_CPUS);
+
+ for (; start_cpu <= end_cpu; start_cpu++) {
+ /* check for duplicates */
+ for (i = 0; i < nr_cpus; i++)
+ if (tmp_cpus[i].cpu == (int)start_cpu)
+ goto invalid;
+
+ if (nr_cpus == max_entries) {
+ max_entries += MAX_NR_CPUS;
+ tmp = realloc(tmp_cpus, max_entries * sizeof(struct perf_cpu));
+ if (tmp == NULL)
+ goto invalid;
+ tmp_cpus = tmp;
+ }
+ tmp_cpus[nr_cpus++].cpu = (int)start_cpu;
+ }
+ if (*p)
+ ++p;
+
+ cpu_list = p;
+ }
+
+ if (nr_cpus > 0)
+ cpus = cpu_map__trim_new(nr_cpus, tmp_cpus);
+ else if (*cpu_list != '\0')
+ cpus = cpu_map__default_new();
+ else
+ cpus = perf_cpu_map__dummy_new();
+invalid:
+ free(tmp_cpus);
+out:
+ return cpus;
+}
+
+struct perf_cpu perf_cpu_map__cpu(const struct perf_cpu_map *cpus, int idx)
+{
+ struct perf_cpu result = {
+ .cpu = -1
+ };
+
+ if (cpus && idx < cpus->nr)
+ return cpus->map[idx];
+
+ return result;
+}
+
+int perf_cpu_map__nr(const struct perf_cpu_map *cpus)
+{
+ return cpus ? cpus->nr : 1;
+}
+
+bool perf_cpu_map__empty(const struct perf_cpu_map *map)
+{
+ return map ? map->map[0].cpu == -1 : true;
+}
+
+int perf_cpu_map__idx(const struct perf_cpu_map *cpus, struct perf_cpu cpu)
+{
+ int low, high;
+
+ if (!cpus)
+ return -1;
+
+ low = 0;
+ high = cpus->nr;
+ while (low < high) {
+ int idx = (low + high) / 2;
+ struct perf_cpu cpu_at_idx = cpus->map[idx];
+
+ if (cpu_at_idx.cpu == cpu.cpu)
+ return idx;
+
+ if (cpu_at_idx.cpu > cpu.cpu)
+ high = idx;
+ else
+ low = idx + 1;
+ }
+
+ return -1;
+}
+
+bool perf_cpu_map__has(const struct perf_cpu_map *cpus, struct perf_cpu cpu)
+{
+ return perf_cpu_map__idx(cpus, cpu) != -1;
+}
+
+struct perf_cpu perf_cpu_map__max(const struct perf_cpu_map *map)
+{
+ struct perf_cpu result = {
+ .cpu = -1
+ };
+
+ // cpu_map__trim_new() qsort()s it, cpu_map__default_new() sorts it as well.
+ return map->nr > 0 ? map->map[map->nr - 1] : result;
+}
+
+/** Is 'b' a subset of 'a'. */
+bool perf_cpu_map__is_subset(const struct perf_cpu_map *a, const struct perf_cpu_map *b)
+{
+ if (a == b || !b)
+ return true;
+ if (!a || b->nr > a->nr)
+ return false;
+
+ for (int i = 0, j = 0; i < a->nr; i++) {
+ if (a->map[i].cpu > b->map[j].cpu)
+ return false;
+ if (a->map[i].cpu == b->map[j].cpu) {
+ j++;
+ if (j == b->nr)
+ return true;
+ }
+ }
+ return false;
+}
+
+/*
+ * Merge two cpumaps
+ *
+ * orig either gets freed and replaced with a new map, or reused
+ * with no reference count change (similar to "realloc")
+ * other has its reference count increased.
+ */
+
+struct perf_cpu_map *perf_cpu_map__merge(struct perf_cpu_map *orig,
+ struct perf_cpu_map *other)
+{
+ struct perf_cpu *tmp_cpus;
+ int tmp_len;
+ int i, j, k;
+ struct perf_cpu_map *merged;
+
+ if (perf_cpu_map__is_subset(orig, other))
+ return orig;
+ if (perf_cpu_map__is_subset(other, orig)) {
+ perf_cpu_map__put(orig);
+ return perf_cpu_map__get(other);
+ }
+
+ tmp_len = orig->nr + other->nr;
+ tmp_cpus = malloc(tmp_len * sizeof(struct perf_cpu));
+ if (!tmp_cpus)
+ return NULL;
+
+ /* Standard merge algorithm from wikipedia */
+ i = j = k = 0;
+ while (i < orig->nr && j < other->nr) {
+ if (orig->map[i].cpu <= other->map[j].cpu) {
+ if (orig->map[i].cpu == other->map[j].cpu)
+ j++;
+ tmp_cpus[k++] = orig->map[i++];
+ } else
+ tmp_cpus[k++] = other->map[j++];
+ }
+
+ while (i < orig->nr)
+ tmp_cpus[k++] = orig->map[i++];
+
+ while (j < other->nr)
+ tmp_cpus[k++] = other->map[j++];
+ assert(k <= tmp_len);
+
+ merged = cpu_map__trim_new(k, tmp_cpus);
+ free(tmp_cpus);
+ perf_cpu_map__put(orig);
+ return merged;
+}