From mboxrd@z Thu Jan 1 00:00:00 1970 Delivery-date: Wed, 10 Mar 2021 09:49:46 +0100 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by lore.white.stw.pengutronix.de with esmtp (Exim 4.92) (envelope-from ) id 1lJuXK-0001A9-Ia for lore@lore.pengutronix.de; Wed, 10 Mar 2021 09:49:46 +0100 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lJuXI-00027g-G3 for lore@pengutronix.de; Wed, 10 Mar 2021 09:49:46 +0100 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Message-Id:Date: Subject:Cc:To:From:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=10EXJ+u3QcuG8IqBdNhFqDkK7kmov8DkQFbx+Uk8jmE=; b=dAfNe//Aeu8RwM2SUxuHGPfDY z34dPv3yEKh14PSG9lsZSCy0ojHTDshLO/QqSPan/iW24pPMewWHO6qs7H9uwjChCZae05Mh9057I Brs8eqdYiS6MIWqMc+CEQFBFF5avV3TSSdjxwtvBKKzbK4Z8q2tlL9yc1RHhJX7wACnTpJbmxVQOD g6qEsKGvZggDPEY+sdb9yH9VV8/F8MLn0g6CSkiLzihogJDhQ6RRgVrJOks8sMbyFCXjsubtd28WI YlwDjAmjgP7umoZ/yCMb6Z/NNMtjTMuCSrJHwZjslqzLaBvz4Yxz40iRMICCCRyviUwGGIHOugmdK zk3kbq+nw==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lJuWA-006LSW-8n; Wed, 10 Mar 2021 08:48:38 +0000 Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lJuVh-006LJc-1a for barebox@lists.infradead.org; Wed, 10 Mar 2021 08:48:07 +0000 Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lJuVf-0001Tk-2w; Wed, 10 Mar 2021 09:48:03 +0100 Received: from afa by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lJuVd-0001zp-MU; Wed, 10 Mar 2021 09:48:01 +0100 From: Ahmad Fatoum To: barebox@lists.infradead.org Cc: Peter Mamonov , Peter Korsgaard , Sascha Hauer Date: Wed, 10 Mar 2021 09:47:59 +0100 Message-Id: <20210310084800.3584-16-a.fatoum@pengutronix.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210310084800.3584-1-a.fatoum@pengutronix.de> References: <20210310084800.3584-1-a.fatoum@pengutronix.de> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210310_084805_369157_062230A8 X-CRM114-Status: GOOD ( 22.97 ) X-BeenThere: barebox@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" X-SA-Exim-Connect-IP: 2001:8b0:10b:1:d65d:64ff:fe57:4e05 X-SA-Exim-Mail-From: barebox-bounces+lore=pengutronix.de@lists.infradead.org X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on metis.ext.pengutronix.de X-Spam-Level: X-Spam-Status: No, score=-3.5 required=4.0 tests=AWL,BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Subject: [PATCH v3 15/16] commands: add new bthread test command X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on metis.ext.pengutronix.de) From: Ahmad Fatoum This command is meant to show how to use the bthread API as well as help with debugging. It's a bit overcomplicated to exercise aspects of the API, like scheduling from both secondary and primary thread. Signed-off-by: Ahmad Fatoum --- commands/Kconfig | 9 +++ commands/Makefile | 1 + commands/bthread.c | 195 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 205 insertions(+) create mode 100644 commands/bthread.c diff --git a/commands/Kconfig b/commands/Kconfig index 520ad4b1dea3..6d84c956e576 100644 --- a/commands/Kconfig +++ b/commands/Kconfig @@ -253,6 +253,15 @@ config CMD_POLLER is_timeout() or one of the various delay functions. The poller command prints informations about registered pollers. +config CMD_BTHREAD + tristate + prompt "bthread" + depends on BTHREAD + help + barebox threads are cooperatively-scheduled (green) threads that are running in + the background whenever code executes is_timeout() or one of the various delay + functions. The bthread command prints informations about registered bthreads. + config CMD_SLICE tristate prompt "slice" diff --git a/commands/Makefile b/commands/Makefile index 034c0e6383d3..cdf14a5e1d8d 100644 --- a/commands/Makefile +++ b/commands/Makefile @@ -129,6 +129,7 @@ obj-$(CONFIG_CMD_MMC_EXTCSD) += mmc_extcsd.o obj-$(CONFIG_CMD_NAND_BITFLIP) += nand-bitflip.o obj-$(CONFIG_CMD_SEED) += seed.o obj-$(CONFIG_CMD_IP_ROUTE_GET) += ip-route-get.o +obj-$(CONFIG_CMD_BTHREAD) += bthread.o obj-$(CONFIG_CMD_UBSAN) += ubsan.o UBSAN_SANITIZE_ubsan.o := y diff --git a/commands/bthread.c b/commands/bthread.c new file mode 100644 index 000000000000..05dfa68cc597 --- /dev/null +++ b/commands/bthread.c @@ -0,0 +1,195 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2021 Ahmad Fatoum, Pengutronix + */ + +#include +#include +#include +#include +#include +#include +#include + +static int bthread_time(void) +{ + uint64_t start = get_time_ns(); + int i = 0; + + /* + * How many background tasks can we have in one second? + * + * A low number here may point to problems with bthreads taking too + * much time. + */ + while (!is_timeout(start, SECOND)) + i++; + + return i; +} + +static int bthread_infinite(void *data) +{ + while (!bthread_should_stop()) + ; + + return 0; +} + +static int bthread_isolated_time(void) +{ + uint64_t start = get_time_ns(); + struct bthread *bthread; + int i = 0; + + bthread = bthread_run(bthread_infinite, NULL, "infinite"); + if (!bthread) + return -ENOMEM; + + /* main thread is the first in the run queue. Newly created bthread + * is the last. So if main_thread explicitly schedules new bthread, + * it will schedule back to main_thread afterwards and we won't + * execute any other threads in-between. + */ + + while (!is_timeout_non_interruptible(start, SECOND)) { + bthread_schedule(bthread); + i += 2; + } + + bthread_stop(bthread); + bthread_free(bthread); + + return i; +} + +static int bthread_printer(void *arg) +{ + volatile u64 start; + volatile int i = 0; + start = get_time_ns(); + + while (!bthread_should_stop()) { + if (!is_timeout_non_interruptible(start, 225 * MSECOND)) + continue; + + if ((long)arg == i++) + printf("%s yield #%d\n", bthread_name(current), i); + start = get_time_ns(); + } + + return i; +} + +static int yields; + +static int bthread_spawner(void *arg) +{ + struct bthread *bthread[4]; + volatile u64 start; + volatile int i = 0; + int ret = 0; + int ecode; + + start = get_time_ns(); + + for (i = 0; i < ARRAY_SIZE(bthread); i++) { + bthread[i] = bthread_run(bthread_printer, (void *)i, + "%s-bthread%u", bthread_name(current), i+1); + if (!bthread[i]) { + ret = -ENOMEM; + goto cleanup; + } + } + + while (!bthread_should_stop()) + ; + +cleanup: + while (i--) { + ecode = bthread_stop(bthread[i]); + bthread_free(bthread[i]); + + if (!ret && (ecode != 4 || yields < ecode)) + ret = -EIO; + } + + return ret; +} + +struct spawn { + struct bthread *bthread; + struct list_head list; +}; + +static int do_bthread(int argc, char *argv[]) +{ + LIST_HEAD(spawners); + struct spawn *spawner, *tmp; + int ret = 0; + int ecode, opt, i = 0; + bool time = false; + + while ((opt = getopt(argc, argv, "itcv")) > 0) { + switch (opt) { + case 'i': + bthread_info(); + break; + case 'c': + yields = bthread_isolated_time(); + printf("%d bthread context switches possible in 1s\n", yields); + break; + case 'v': + spawner = xzalloc(sizeof(*spawner)); + spawner->bthread = bthread_run(bthread_spawner, NULL, + "spawner%u", ++i); + if (!spawner->bthread) { + free(spawner); + ret = -ENOMEM; + goto cleanup; + } + + /* We create intermediate spawning threads to test thread + * creation and scheduling from non-main thread. + */ + list_add(&spawner->list, &spawners); + + /* fallthrough */ + case 't': + time = true; + } + } + + if (time) { + yields = bthread_time(); + printf("%d bthread yield calls in 1s\n", yields); + } + +cleanup: + list_for_each_entry_safe(spawner, tmp, &spawners, list) { + ecode = bthread_stop(spawner->bthread); + bthread_free(spawner->bthread); + if (!ret && ecode) + ret = ecode; + free(spawner); + } + + return ret; +} + +BAREBOX_CMD_HELP_START(bthread) + BAREBOX_CMD_HELP_TEXT("print info about registered barebox threads") + BAREBOX_CMD_HELP_TEXT("") + BAREBOX_CMD_HELP_TEXT("Options:") + BAREBOX_CMD_HELP_OPT ("-i", "Print information about registered bthreads") + BAREBOX_CMD_HELP_OPT ("-t", "measure how many bthreads we currently run in 1s") + BAREBOX_CMD_HELP_OPT ("-c", "count maximum context switches in 1s") + BAREBOX_CMD_HELP_OPT ("-v", "verify correct bthread operation") +BAREBOX_CMD_HELP_END + +BAREBOX_CMD_START(bthread) + .cmd = do_bthread, + BAREBOX_CMD_DESC("print info about registered bthreads") + BAREBOX_CMD_GROUP(CMD_GRP_MISC) + BAREBOX_CMD_HELP(cmd_bthread_help) +BAREBOX_CMD_END -- 2.29.2 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox