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>

1 files changed, 184 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;
+}