Re: [PATCH 4/7] perf/bench-futex: Add --mlockall parameter

From: Arnaldo Carvalho de Melo
Date: Mon Aug 09 2021 - 10:56:28 EST

Em Sun, Aug 08, 2021 at 09:32:58PM -0700, Davidlohr Bueso escreveu:
> This adds, across all futex benchmarks, the -m/--mlockall option
> which is a common operation for realtime workloads by not incurring
> in page faults in paths that want determinism. As such, threads
> started after a call to mlockall(2) will generate page faults
> immediately since the new stack is immediately forced to memory,
> due to the MCL_FUTURE flag.

Applied.

At some point these options could be handled in a common
futex_parse_options() function that would consume argv[] and then the
specific futex benchmarks would continue from where the common function
left off.

- Arnaldo

> Signed-off-by: Davidlohr Bueso <dbueso@xxxxxxx>
> ---
> tools/perf/bench/futex-hash.c | 7 +++++++
> tools/perf/bench/futex-lock-pi.c | 7 +++++++
> tools/perf/bench/futex-requeue.c | 7 +++++++
> tools/perf/bench/futex-wake-parallel.c | 8 ++++++++
> tools/perf/bench/futex-wake.c | 8 ++++++++
> tools/perf/bench/futex.h | 1 +
> 6 files changed, 38 insertions(+)
>
> diff --git a/tools/perf/bench/futex-hash.c b/tools/perf/bench/futex-hash.c
> index b71a34204b79..af9fbb409472 100644
> --- a/tools/perf/bench/futex-hash.c
> +++ b/tools/perf/bench/futex-hash.c
> @@ -20,6 +20,7 @@
> #include <linux/kernel.h>
> #include <linux/zalloc.h>
> #include <sys/time.h>
> +#include <sys/mman.h>
> #include <perf/cpumap.h>
>
> #include "../util/stat.h"
> @@ -55,6 +56,7 @@ static const struct option options[] = {
> OPT_UINTEGER('f', "futexes", &params.nfutexes, "Specify amount of futexes per threads"),
> OPT_BOOLEAN( 's', "silent", &params.silent, "Silent mode: do not display data/details"),
> OPT_BOOLEAN( 'S', "shared", &params.fshared, "Use shared futexes instead of private ones"),
> + OPT_BOOLEAN( 'm', "mlockall", &params.mlockall, "Lock all current and future memory"),
> OPT_END()
> };
>
> @@ -141,6 +143,11 @@ int bench_futex_hash(int argc, const char **argv)
> act.sa_sigaction = toggle_done;
> sigaction(SIGINT, &act, NULL);
>
> + if (params.mlockall) {
> + if (mlockall(MCL_CURRENT | MCL_FUTURE))
> + err(EXIT_FAILURE, "mlockall");
> + }
> +
> if (!params.nthreads) /* default to the number of CPUs */
> params.nthreads = cpu->nr;
>
> diff --git a/tools/perf/bench/futex-lock-pi.c b/tools/perf/bench/futex-lock-pi.c
> index bc208edf3de3..d2927d2eb3f7 100644
> --- a/tools/perf/bench/futex-lock-pi.c
> +++ b/tools/perf/bench/futex-lock-pi.c
> @@ -21,6 +21,7 @@
> #include <err.h>
> #include <stdlib.h>
> #include <sys/time.h>
> +#include <sys/mman.h>
>
> struct worker {
> int tid;
> @@ -47,6 +48,7 @@ static const struct option options[] = {
> OPT_BOOLEAN( 'M', "multi", &params.multi, "Use multiple futexes"),
> OPT_BOOLEAN( 's', "silent", &params.silent, "Silent mode: do not display data/details"),
> OPT_BOOLEAN( 'S', "shared", &params.fshared, "Use shared futexes instead of private ones"),
> + OPT_BOOLEAN( 'm', "mlockall", &params.mlockall, "Lock all current and future memory"),
> OPT_END()
> };
>
> @@ -164,6 +166,11 @@ int bench_futex_lock_pi(int argc, const char **argv)
> act.sa_sigaction = toggle_done;
> sigaction(SIGINT, &act, NULL);
>
> + if (params.mlockall) {
> + if (mlockall(MCL_CURRENT | MCL_FUTURE))
> + err(EXIT_FAILURE, "mlockall");
> + }
> +
> if (!params.nthreads)
> params.nthreads = cpu->nr;
>
> diff --git a/tools/perf/bench/futex-requeue.c b/tools/perf/bench/futex-requeue.c
> index 4001312122be..88cb7e2a6729 100644
> --- a/tools/perf/bench/futex-requeue.c
> +++ b/tools/perf/bench/futex-requeue.c
> @@ -27,6 +27,7 @@
> #include <err.h>
> #include <stdlib.h>
> #include <sys/time.h>
> +#include <sys/mman.h>
>
> static u_int32_t futex1 = 0, futex2 = 0;
>
> @@ -50,6 +51,7 @@ static const struct option options[] = {
> OPT_UINTEGER('q', "nrequeue", &params.nrequeue, "Specify amount of threads to requeue at once"),
> OPT_BOOLEAN( 's', "silent", &params.silent, "Silent mode: do not display data/details"),
> OPT_BOOLEAN( 'S', "shared", &params.fshared, "Use shared futexes instead of private ones"),
> + OPT_BOOLEAN( 'm', "mlockall", &params.mlockall, "Lock all current and future memory"),
> OPT_END()
> };
>
> @@ -133,6 +135,11 @@ int bench_futex_requeue(int argc, const char **argv)
> act.sa_sigaction = toggle_done;
> sigaction(SIGINT, &act, NULL);
>
> + if (params.mlockall) {
> + if (mlockall(MCL_CURRENT | MCL_FUTURE))
> + err(EXIT_FAILURE, "mlockall");
> + }
> +
> if (!params.nthreads)
> params.nthreads = cpu->nr;
>
> diff --git a/tools/perf/bench/futex-wake-parallel.c b/tools/perf/bench/futex-wake-parallel.c
> index ea4fdea6e2f3..ef1f8237fd81 100644
> --- a/tools/perf/bench/futex-wake-parallel.c
> +++ b/tools/perf/bench/futex-wake-parallel.c
> @@ -34,6 +34,7 @@ int bench_futex_wake_parallel(int argc __maybe_unused, const char **argv __maybe
> #include <err.h>
> #include <stdlib.h>
> #include <sys/time.h>
> +#include <sys/mman.h>
>
> struct thread_data {
> pthread_t worker;
> @@ -61,6 +62,8 @@ static const struct option options[] = {
> OPT_UINTEGER('w', "nwakers", &params.nwakes, "Specify amount of waking threads"),
> OPT_BOOLEAN( 's', "silent", &params.silent, "Silent mode: do not display data/details"),
> OPT_BOOLEAN( 'S', "shared", &params.fshared, "Use shared futexes instead of private ones"),
> + OPT_BOOLEAN( 'm', "mlockall", &params.mlockall, "Lock all current and future memory"),
> +
> OPT_END()
> };
>
> @@ -238,6 +241,11 @@ int bench_futex_wake_parallel(int argc, const char **argv)
> act.sa_sigaction = toggle_done;
> sigaction(SIGINT, &act, NULL);
>
> + if (params.mlockall) {
> + if (mlockall(MCL_CURRENT | MCL_FUTURE))
> + err(EXIT_FAILURE, "mlockall");
> + }
> +
> cpu = perf_cpu_map__new(NULL);
> if (!cpu)
> err(EXIT_FAILURE, "calloc");
> diff --git a/tools/perf/bench/futex-wake.c b/tools/perf/bench/futex-wake.c
> index 1cf651c8ee5c..40e492c7996a 100644
> --- a/tools/perf/bench/futex-wake.c
> +++ b/tools/perf/bench/futex-wake.c
> @@ -27,6 +27,7 @@
> #include <err.h>
> #include <stdlib.h>
> #include <sys/time.h>
> +#include <sys/mman.h>
>
> /* all threads will block on the same futex */
> static u_int32_t futex1 = 0;
> @@ -51,6 +52,8 @@ static const struct option options[] = {
> OPT_UINTEGER('w', "nwakes", &params.nwakes, "Specify amount of threads to wake at once"),
> OPT_BOOLEAN( 's', "silent", &params.silent, "Silent mode: do not display data/details"),
> OPT_BOOLEAN( 'S', "shared", &params.fshared, "Use shared futexes instead of private ones"),
> + OPT_BOOLEAN( 'm', "mlockall", &params.mlockall, "Lock all current and future memory"),
> +
> OPT_END()
> };
>
> @@ -141,6 +144,11 @@ int bench_futex_wake(int argc, const char **argv)
> act.sa_sigaction = toggle_done;
> sigaction(SIGINT, &act, NULL);
>
> + if (params.mlockall) {
> + if (mlockall(MCL_CURRENT | MCL_FUTURE))
> + err(EXIT_FAILURE, "mlockall");
> + }
> +
> if (!params.nthreads)
> params.nthreads = cpu->nr;
>
> diff --git a/tools/perf/bench/futex.h b/tools/perf/bench/futex.h
> index f7cd22bbd677..1c8fa469993f 100644
> --- a/tools/perf/bench/futex.h
> +++ b/tools/perf/bench/futex.h
> @@ -19,6 +19,7 @@ static int futex_flag = 0;
> struct bench_futex_parameters {
> bool silent;
> bool fshared;
> + bool mlockall;
> bool multi; /* lock-pi */
> unsigned int runtime; /* seconds*/
> unsigned int nthreads;
> --
> 2.26.2
>

--

- Arnaldo