The variables nr_cpus_onln and max_caches are dynamic alternatives for MAX_NR_CPUS and MAX_CACHES as they are initialized at runtime. MAX_NR_CPUS is still used by DECLARE_BITMAP() at compile time, however, nr_cpus_onln replaces it elsewhere throughout perf.
This patch was tested using "perf record -a -g" on both an eight socket (288 CPUs) system and a single socket (36 CPUs) system. Each system was then rebooted single socket (36 CPUs) / eight socket (288 CPUs) and "perf report" used to read the perf.data file. "perf report --header" was used to confirm that each perf.data had information on 288 CPUs / 36 CPUs. This patch is meant to be built against perf tools: Increase MAX_NR_CPUS and MAX_CACHES (commit 9f94c7f947e919c343b30f080285af53d0fa9902). Signed-off-by: Kyle Meyer <[email protected]> Cc: Russ Anderson <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Arnaldo Carvalho de Melo <[email protected]> Cc: Alexander Shishkin <[email protected]> Cc: Jiri Olsa <[email protected]> Cc: Namhyung Kim <[email protected]> Cc: [email protected] --- tools/perf/perf.c | 10 ++++++++++ tools/perf/perf.h | 1 + tools/perf/util/cpumap.c | 6 +++--- tools/perf/util/header.c | 5 +++-- tools/perf/util/machine.c | 11 +++++------ tools/perf/util/stat.c | 4 ++-- tools/perf/util/svghelper.c | 10 +++++----- 7 files changed, 29 insertions(+), 18 deletions(-) diff --git a/tools/perf/perf.c b/tools/perf/perf.c index 97e2628ea5dd..0d0162fb4e24 100644 --- a/tools/perf/perf.c +++ b/tools/perf/perf.c @@ -428,6 +428,16 @@ int main(int argc, const char **argv) const char *cmd; char sbuf[STRERR_BUFSIZE]; + nr_cpus_onln = sysconf(_SC_NPROCESSORS_ONLN); + if (nr_cpus_onln < 0) { + fprintf(stderr, "Cannot determine the number of CPUs currently online.\n"); + goto out; + } + if (nr_cpus_onln > MAX_NR_CPUS) { + fprintf(stderr, "The number of CPUs currently online is too large, consider raising MAX_NR_CPUS.\n"); + nr_cpus_onln = MAX_NR_CPUS; + } + /* libsubcmd init */ exec_cmd_init("perf", PREFIX, PERF_EXEC_PATH, EXEC_PATH_ENVIRONMENT); pager_init(PERF_PAGER_ENVIRONMENT); diff --git a/tools/perf/perf.h b/tools/perf/perf.h index 74d0124d38f3..603391cac85b 100644 --- a/tools/perf/perf.h +++ b/tools/perf/perf.h @@ -29,6 +29,7 @@ static inline unsigned long long rdclock(void) #define MAX_NR_CPUS 2048 #endif +int nr_cpus_onln; extern const char *input_name; extern bool perf_host, perf_guest; extern const char perf_version_string[]; diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c index 3acfbe34ebaf..f634c56b1388 100644 --- a/tools/perf/util/cpumap.c +++ b/tools/perf/util/cpumap.c @@ -72,7 +72,7 @@ struct cpu_map *cpu_map__read(FILE *file) int new_max = nr_cpus + cpu - prev - 1; if (new_max >= max_entries) { - max_entries = new_max + MAX_NR_CPUS / 2; + max_entries = new_max + nr_cpus_onln / 2; tmp = realloc(tmp_cpus, max_entries * sizeof(int)); if (tmp == NULL) goto out_free_tmp; @@ -83,7 +83,7 @@ struct cpu_map *cpu_map__read(FILE *file) tmp_cpus[nr_cpus++] = prev; } if (nr_cpus == max_entries) { - max_entries += MAX_NR_CPUS; + max_entries += nr_cpus_onln; tmp = realloc(tmp_cpus, max_entries * sizeof(int)); if (tmp == NULL) goto out_free_tmp; @@ -170,7 +170,7 @@ struct cpu_map *cpu_map__new(const char *cpu_list) goto invalid; if (nr_cpus == max_entries) { - max_entries += MAX_NR_CPUS; + max_entries += nr_cpus_onln; tmp = realloc(tmp_cpus, max_entries * sizeof(int)); if (tmp == NULL) goto invalid; diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c index c24db7f4909c..030c0a8f6664 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -1125,11 +1125,12 @@ static int build_caches(struct cpu_cache_level caches[], u32 size, u32 *cntp) static int write_cache(struct feat_fd *ff, struct perf_evlist *evlist __maybe_unused) { - struct cpu_cache_level caches[MAX_CACHES]; + u32 max_caches = (nr_cpus_onln * 4); + struct cpu_cache_level caches[max_caches]; u32 cnt = 0, i, version = 1; int ret; - ret = build_caches(caches, MAX_CACHES, &cnt); + ret = build_caches(caches, max_caches, &cnt); if (ret) goto out; diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index cf826eca3aaf..92720240676d 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -2615,7 +2615,7 @@ int __machine__synthesize_threads(struct machine *machine, struct perf_tool *too pid_t machine__get_current_tid(struct machine *machine, int cpu) { - if (cpu < 0 || cpu >= MAX_NR_CPUS || !machine->current_tid) + if (cpu < 0 || cpu >= nr_cpus_onln || !machine->current_tid) return -1; return machine->current_tid[cpu]; @@ -2632,16 +2632,15 @@ int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid, if (!machine->current_tid) { int i; - machine->current_tid = calloc(MAX_NR_CPUS, sizeof(pid_t)); + machine->current_tid = calloc(nr_cpus_onln, sizeof(pid_t)); if (!machine->current_tid) return -ENOMEM; - for (i = 0; i < MAX_NR_CPUS; i++) + for (i = 0; i < nr_cpus_onln; i++) machine->current_tid[i] = -1; } - if (cpu >= MAX_NR_CPUS) { - pr_err("Requested CPU %d too large. ", cpu); - pr_err("Consider raising MAX_NR_CPUS\n"); + if (cpu >= nr_cpus_onln) { + pr_err("Requested CPU %d too large, there are %d CPUs currently online.\n", cpu, nr_cpus_onln); return -EINVAL; } diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c index db8a6cf336be..f87bdc140a4b 100644 --- a/tools/perf/util/stat.c +++ b/tools/perf/util/stat.c @@ -208,7 +208,7 @@ void perf_evlist__reset_stats(struct perf_evlist *evlist) static void zero_per_pkg(struct perf_evsel *counter) { if (counter->per_pkg_mask) - memset(counter->per_pkg_mask, 0, MAX_NR_CPUS); + memset(counter->per_pkg_mask, 0, nr_cpus_onln); } static int check_per_pkg(struct perf_evsel *counter, @@ -227,7 +227,7 @@ static int check_per_pkg(struct perf_evsel *counter, return 0; if (!mask) { - mask = zalloc(MAX_NR_CPUS); + mask = zalloc(nr_cpus_onln); if (!mask) return -ENOMEM; diff --git a/tools/perf/util/svghelper.c b/tools/perf/util/svghelper.c index 76cc54000483..4c38f70520c5 100644 --- a/tools/perf/util/svghelper.c +++ b/tools/perf/util/svghelper.c @@ -705,7 +705,7 @@ static void scan_thread_topology(int *map, struct topology *t, int cpu, int *pos for_each_set_bit(thr, cpumask_bits(&t->sib_thr[i]), - MAX_NR_CPUS) + nr_cpus_onln) if (map[thr] == -1) map[thr] = (*pos)++; } @@ -720,7 +720,7 @@ static void scan_core_topology(int *map, struct topology *t) for (i = 0; i < t->sib_core_nr; i++) for_each_set_bit(cpu, cpumask_bits(&t->sib_core[i]), - MAX_NR_CPUS) + nr_cpus_onln) scan_thread_topology(map, t, cpu, &pos); } @@ -737,7 +737,7 @@ static int str_to_bitmap(char *s, cpumask_t *b) for (i = 0; i < m->nr; i++) { c = m->map[i]; - if (c >= MAX_NR_CPUS) { + if (c >= nr_cpus_onln) { ret = -1; break; } @@ -784,13 +784,13 @@ int svg_build_topology_map(char *sib_core, int sib_core_nr, sib_thr += strlen(sib_thr) + 1; } - topology_map = malloc(sizeof(int) * MAX_NR_CPUS); + topology_map = malloc(sizeof(int) * nr_cpus_onln); if (!topology_map) { fprintf(stderr, "topology: no memory\n"); goto exit; } - for (i = 0; i < MAX_NR_CPUS; i++) + for (i = 0; i < nr_cpus_onln; i++) topology_map[i] = -1; scan_core_topology(topology_map, &t); -- 2.12.3
