On Thu, Jun 6, 2024 at 9:44 PM Athira Rajeev
<atraj...@linux.vnet.ibm.com> wrote:
>
> Perf bench futex fails as below when attempted to run on
> on a powerpc system:
>
> ./perf bench futex all
> Running futex/hash benchmark...
> Run summary [PID 626307]: 80 threads, each operating on 1024 [private]
> futexes for 10 secs.
>
> perf: pthread_create: No such file or directory
>
> In the setup where this perf bench was ran, difference was that
> partition had 640 CPU's, but not all CPUs were online. 80 CPUs
> were online. While blocking the threads with futex_wait, code
> sets the affinity using cpumask. The cpumask size used is 80
> which is picked from "nrcpus = perf_cpu_map__nr(cpu)". Here the
> benchmark reports fail while setting affinity for cpu number which
> is greater than 80 or higher, because it attempts to set a bit
> position which is not allocated on the cpumask. Fix this by changing
> the size of cpumask to number of possible cpus and not the number
> of online cpus.
>
> Signed-off-by: Athira Rajeev <atraj...@linux.vnet.ibm.com>
For the series:
Reviewed-by: Ian Rogers <irog...@google.com>
Thanks,
Ian
> ---
> tools/perf/bench/futex-hash.c | 2 +-
> tools/perf/bench/futex-lock-pi.c | 2 +-
> tools/perf/bench/futex-requeue.c | 2 +-
> tools/perf/bench/futex-wake-parallel.c | 2 +-
> tools/perf/bench/futex-wake.c | 2 +-
> 5 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/tools/perf/bench/futex-hash.c b/tools/perf/bench/futex-hash.c
> index 0c69d20efa32..b472eded521b 100644
> --- a/tools/perf/bench/futex-hash.c
> +++ b/tools/perf/bench/futex-hash.c
> @@ -174,7 +174,7 @@ int bench_futex_hash(int argc, const char **argv)
> pthread_attr_init(&thread_attr);
> gettimeofday(&bench__start, NULL);
>
> - nrcpus = perf_cpu_map__nr(cpu);
> + nrcpus = cpu__max_cpu().cpu;
> cpuset = CPU_ALLOC(nrcpus);
> BUG_ON(!cpuset);
> size = CPU_ALLOC_SIZE(nrcpus);
> diff --git a/tools/perf/bench/futex-lock-pi.c
> b/tools/perf/bench/futex-lock-pi.c
> index 7a4973346180..0416120c091b 100644
> --- a/tools/perf/bench/futex-lock-pi.c
> +++ b/tools/perf/bench/futex-lock-pi.c
> @@ -122,7 +122,7 @@ static void create_threads(struct worker *w, struct
> perf_cpu_map *cpu)
> {
> cpu_set_t *cpuset;
> unsigned int i;
> - int nrcpus = perf_cpu_map__nr(cpu);
> + int nrcpus = cpu__max_cpu().cpu;
> size_t size;
>
> threads_starting = params.nthreads;
> diff --git a/tools/perf/bench/futex-requeue.c
> b/tools/perf/bench/futex-requeue.c
> index d9ad736c1a3e..aad5bfc4fe18 100644
> --- a/tools/perf/bench/futex-requeue.c
> +++ b/tools/perf/bench/futex-requeue.c
> @@ -125,7 +125,7 @@ static void block_threads(pthread_t *w, struct
> perf_cpu_map *cpu)
> {
> cpu_set_t *cpuset;
> unsigned int i;
> - int nrcpus = perf_cpu_map__nr(cpu);
> + int nrcpus = cpu__max_cpu().cpu;
> size_t size;
>
> threads_starting = params.nthreads;
> diff --git a/tools/perf/bench/futex-wake-parallel.c
> b/tools/perf/bench/futex-wake-parallel.c
> index b66df553e561..90a5b91bf139 100644
> --- a/tools/perf/bench/futex-wake-parallel.c
> +++ b/tools/perf/bench/futex-wake-parallel.c
> @@ -149,7 +149,7 @@ static void block_threads(pthread_t *w, struct
> perf_cpu_map *cpu)
> {
> cpu_set_t *cpuset;
> unsigned int i;
> - int nrcpus = perf_cpu_map__nr(cpu);
> + int nrcpus = cpu__max_cpu().cpu;
> size_t size;
>
> threads_starting = params.nthreads;
> diff --git a/tools/perf/bench/futex-wake.c b/tools/perf/bench/futex-wake.c
> index 690fd6d3da13..49b3c89b0b35 100644
> --- a/tools/perf/bench/futex-wake.c
> +++ b/tools/perf/bench/futex-wake.c
> @@ -100,7 +100,7 @@ static void block_threads(pthread_t *w, struct
> perf_cpu_map *cpu)
> cpu_set_t *cpuset;
> unsigned int i;
> size_t size;
> - int nrcpus = perf_cpu_map__nr(cpu);
> + int nrcpus = cpu__max_cpu().cpu;
> threads_starting = params.nthreads;
>
> cpuset = CPU_ALLOC(nrcpus);
> --
> 2.43.0
>
