[PATCH 04/18] perf machine: Add nr_cpus_avail()

From: Arnaldo Carvalho de Melo
Date: Wed May 23 2018 - 15:28:22 EST


From: Adrian Hunter <adrian.hunter@xxxxxxxxx>

Add a function to return the number of the machine's available CPUs.

Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx>
Cc: Andy Lutomirski <luto@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
Cc: H. Peter Anvin <hpa@xxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Joerg Roedel <joro@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: x86@xxxxxxxxxx
Link: http://lkml.kernel.org/r/1526986485-6562-5-git-send-email-adrian.hunter@xxxxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/util/env.c | 13 +++++++++++++
tools/perf/util/env.h | 1 +
tools/perf/util/machine.c | 5 +++++
tools/perf/util/machine.h | 1 +
4 files changed, 20 insertions(+)

diff --git a/tools/perf/util/env.c b/tools/perf/util/env.c
index 319fb0a0d05e..59f38c7693f8 100644
--- a/tools/perf/util/env.c
+++ b/tools/perf/util/env.c
@@ -106,11 +106,24 @@ static int perf_env__read_arch(struct perf_env *env)
return env->arch ? 0 : -ENOMEM;
}

+static int perf_env__read_nr_cpus_avail(struct perf_env *env)
+{
+ if (env->nr_cpus_avail == 0)
+ env->nr_cpus_avail = cpu__max_present_cpu();
+
+ return env->nr_cpus_avail ? 0 : -ENOENT;
+}
+
const char *perf_env__raw_arch(struct perf_env *env)
{
return env && !perf_env__read_arch(env) ? env->arch : "unknown";
}

+int perf_env__nr_cpus_avail(struct perf_env *env)
+{
+ return env && !perf_env__read_nr_cpus_avail(env) ? env->nr_cpus_avail : 0;
+}
+
void cpu_cache_level__free(struct cpu_cache_level *cache)
{
free(cache->type);
diff --git a/tools/perf/util/env.h b/tools/perf/util/env.h
index 62e193948608..1f3ccc368530 100644
--- a/tools/perf/util/env.h
+++ b/tools/perf/util/env.h
@@ -77,5 +77,6 @@ void cpu_cache_level__free(struct cpu_cache_level *cache);

const char *perf_env__arch(struct perf_env *env);
const char *perf_env__raw_arch(struct perf_env *env);
+int perf_env__nr_cpus_avail(struct perf_env *env);

#endif /* __PERF_ENV_H */
diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c
index e011a7160380..f62ecd9c36e8 100644
--- a/tools/perf/util/machine.c
+++ b/tools/perf/util/machine.c
@@ -2305,6 +2305,11 @@ bool machine__is(struct machine *machine, const char *arch)
return machine && !strcmp(perf_env__raw_arch(machine->env), arch);
}

+int machine__nr_cpus_avail(struct machine *machine)
+{
+ return machine ? perf_env__nr_cpus_avail(machine->env) : 0;
+}
+
int machine__get_kernel_start(struct machine *machine)
{
struct map *map = machine__kernel_map(machine);
diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h
index b31d33b5aa2a..2d2b092ba753 100644
--- a/tools/perf/util/machine.h
+++ b/tools/perf/util/machine.h
@@ -189,6 +189,7 @@ static inline bool machine__is_host(struct machine *machine)
}

bool machine__is(struct machine *machine, const char *arch);
+int machine__nr_cpus_avail(struct machine *machine);

struct thread *__machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid);
struct thread *machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid);
--
2.14.3