libperf: Add perf_cpu_map__new()/perf_cpu_map__read() functions

Moving the following functions from tools/perf:

  cpu_map__new()
  cpu_map__read()

to libperf with the following names:

  perf_cpu_map__new()
  perf_cpu_map__read()

Committer notes:

Fixed up this one:

  tools/perf/arch/arm/util/cs-etm.c

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20190721112506.12306-44-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

4 files changed, 193 insertions, 0 deletions

diff --git a/tools/perf/lib/cpumap.c b/tools/perf/lib/cpumap.c
index f3cfb4c71106..a5d4f7ff7174 100644
--- a/tools/perf/lib/cpumap.c
+++ b/tools/perf/lib/cpumap.c
@@ -5,6 +5,10 @@
 #include <internal/cpumap.h>
 #include <asm/bug.h>
 #include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <ctype.h>
+#include <limits.h>
 
 struct perf_cpu_map *perf_cpu_map__dummy_new(void)
 {
@@ -40,3 +44,183 @@ 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 = malloc(sizeof(*cpus) + nr_cpus * sizeof(int));
+        if (cpus != NULL) {
+                int i;
+
+                for (i = 0; i < nr_cpus; ++i)
+                        cpus->map[i] = i;
+
+                cpus->nr = nr_cpus;
+                refcount_set(&cpus->refcnt, 1);
+        }
+
+        return cpus;
+}
+
+static struct perf_cpu_map *cpu_map__trim_new(int nr_cpus, int *tmp_cpus)
+{
+        size_t payload_size = nr_cpus * sizeof(int);
+        struct perf_cpu_map *cpus = malloc(sizeof(*cpus) + payload_size);
+
+        if (cpus != NULL) {
+                cpus->nr = nr_cpus;
+                memcpy(cpus->map, tmp_cpus, payload_size);
+                refcount_set(&cpus->refcnt, 1);
+        }
+
+        return cpus;
+}
+
+struct perf_cpu_map *perf_cpu_map__read(FILE *file)
+{
+        struct perf_cpu_map *cpus = NULL;
+        int nr_cpus = 0;
+        int *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;
+
+                        if (new_max >= max_entries) {
+                                max_entries = new_max + MAX_NR_CPUS / 2;
+                                tmp = realloc(tmp_cpus, max_entries * sizeof(int));
+                                if (tmp == NULL)
+                                        goto out_free_tmp;
+                                tmp_cpus = tmp;
+                        }
+
+                        while (++prev < cpu)
+                                tmp_cpus[nr_cpus++] = prev;
+                }
+                if (nr_cpus == max_entries) {
+                        max_entries += MAX_NR_CPUS;
+                        tmp = realloc(tmp_cpus, max_entries * sizeof(int));
+                        if (tmp == NULL)
+                                goto out_free_tmp;
+                        tmp_cpus = tmp;
+                }
+
+                tmp_cpus[nr_cpus++] = 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;
+        int *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;
+                }
+
+                for (; start_cpu <= end_cpu; start_cpu++) {
+                        /* check for duplicates */
+                        for (i = 0; i < nr_cpus; i++)
+                                if (tmp_cpus[i] == (int)start_cpu)
+                                        goto invalid;
+
+                        if (nr_cpus == max_entries) {
+                                max_entries += MAX_NR_CPUS;
+                                tmp = realloc(tmp_cpus, max_entries * sizeof(int));
+                                if (tmp == NULL)
+                                        goto invalid;
+                                tmp_cpus = tmp;
+                        }
+                        tmp_cpus[nr_cpus++] = (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;
+}
diff --git a/tools/perf/lib/include/internal/cpumap.h b/tools/perf/lib/include/internal/cpumap.h
index 53ce95374b05..3306319f7df8 100644
--- a/tools/perf/lib/include/internal/cpumap.h
+++ b/tools/perf/lib/include/internal/cpumap.h
@@ -10,4 +10,8 @@ struct perf_cpu_map {
         int             map[];
 };
 
+#ifndef MAX_NR_CPUS
+#define MAX_NR_CPUS     2048
+#endif
+
 #endif /* __LIBPERF_INTERNAL_CPUMAP_H */
diff --git a/tools/perf/lib/include/perf/cpumap.h b/tools/perf/lib/include/perf/cpumap.h
index e16c2515a499..b4a9283a5dfa 100644
--- a/tools/perf/lib/include/perf/cpumap.h
+++ b/tools/perf/lib/include/perf/cpumap.h
@@ -3,10 +3,13 @@
 #define __LIBPERF_CPUMAP_H
 
 #include <perf/core.h>
+#include <stdio.h>
 
 struct perf_cpu_map;
 
 LIBPERF_API struct perf_cpu_map *perf_cpu_map__dummy_new(void);
+LIBPERF_API struct perf_cpu_map *perf_cpu_map__new(const char *cpu_list);
+LIBPERF_API struct perf_cpu_map *perf_cpu_map__read(FILE *file);
 LIBPERF_API struct perf_cpu_map *perf_cpu_map__get(struct perf_cpu_map *map);
 LIBPERF_API void perf_cpu_map__put(struct perf_cpu_map *map);
 
diff --git a/tools/perf/lib/libperf.map b/tools/perf/lib/libperf.map
index 168339f89a2e..e38473a8f32f 100644
--- a/tools/perf/lib/libperf.map
+++ b/tools/perf/lib/libperf.map
@@ -4,6 +4,8 @@ LIBPERF_0.0.1 {
                 perf_cpu_map__dummy_new;
                 perf_cpu_map__get;
                 perf_cpu_map__put;
+                perf_cpu_map__new;
+                perf_cpu_map__read;
                 perf_thread_map__new_dummy;
                 perf_thread_map__set_pid;
                 perf_thread_map__comm;