From patchwork Fri Apr 9 13:29:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Max Reitz X-Patchwork-Id: 12194171 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id ADC5BC433ED for ; Fri, 9 Apr 2021 13:32:17 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 316D2610A4 for ; Fri, 9 Apr 2021 13:32:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 316D2610A4 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:52290 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lUrFA-0005DS-A9 for qemu-devel@archiver.kernel.org; Fri, 09 Apr 2021 09:32:16 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:35214) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUrD4-00033o-C9 for qemu-devel@nongnu.org; Fri, 09 Apr 2021 09:30:13 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:42798) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUrCx-0006JO-Ie for qemu-devel@nongnu.org; Fri, 09 Apr 2021 09:30:06 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1617974998; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=ozyvUMwTUWB5EMkecsm7lCgbLvNzDma8A7uIYIHcNGo=; b=Wo56f6qlAhaV7P3IBRNWPftPS6HD/I3Obt/0UAfLGb298nsnCpF10dmcRrt5QDe08OhGJ/ yyp0UozYS0K5tT4eE/0fFUehmC3XzYAh7IkLUrmnZfC1bAJOBYe/nS2MAbaoKF/eWz3nSr orXMnqgcWLDP6rvefd6FVkYTmtCq1zg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-556-gavCH29WOE67-6mpD8EMfg-1; Fri, 09 Apr 2021 09:29:57 -0400 X-MC-Unique: gavCH29WOE67-6mpD8EMfg-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 10C218030A1; Fri, 9 Apr 2021 13:29:56 +0000 (UTC) Received: from localhost (ovpn-114-67.ams2.redhat.com [10.36.114.67]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 9AB6910016FE; Fri, 9 Apr 2021 13:29:55 +0000 (UTC) From: Max Reitz To: qemu-block@nongnu.org Subject: [PATCH v2 2/3] test-blockjob: Test job_wait_unpaused() Date: Fri, 9 Apr 2021 15:29:46 +0200 Message-Id: <20210409132948.195511-3-mreitz@redhat.com> In-Reply-To: <20210409132948.195511-1-mreitz@redhat.com> References: <20210409132948.195511-1-mreitz@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=mreitz@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Received-SPF: pass client-ip=63.128.21.124; envelope-from=mreitz@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Vladimir Sementsov-Ogievskiy , John Snow , qemu-devel@nongnu.org, Max Reitz Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Create a job that remains on STANDBY after a drained section, and see that invoking job_wait_unpaused() will get it unstuck. Signed-off-by: Max Reitz --- tests/unit/test-blockjob.c | 140 +++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) diff --git a/tests/unit/test-blockjob.c b/tests/unit/test-blockjob.c index 7519847912..b7736e298d 100644 --- a/tests/unit/test-blockjob.c +++ b/tests/unit/test-blockjob.c @@ -16,6 +16,7 @@ #include "block/blockjob_int.h" #include "sysemu/block-backend.h" #include "qapi/qmp/qdict.h" +#include "iothread.h" static const BlockJobDriver test_block_job_driver = { .job_driver = { @@ -375,6 +376,144 @@ static void test_cancel_concluded(void) cancel_common(s); } +/* (See test_yielding_driver for the job description) */ +typedef struct YieldingJob { + BlockJob common; + bool should_complete; +} YieldingJob; + +static void yielding_job_complete(Job *job, Error **errp) +{ + YieldingJob *s = container_of(job, YieldingJob, common.job); + s->should_complete = true; + job_enter(job); +} + +static int coroutine_fn yielding_job_run(Job *job, Error **errp) +{ + YieldingJob *s = container_of(job, YieldingJob, common.job); + + job_transition_to_ready(job); + + while (!s->should_complete) { + job_yield(job); + } + + return 0; +} + +/* + * This job transitions immediately to the READY state, and then + * yields until it is to complete. + */ +static const BlockJobDriver test_yielding_driver = { + .job_driver = { + .instance_size = sizeof(YieldingJob), + .free = block_job_free, + .user_resume = block_job_user_resume, + .run = yielding_job_run, + .complete = yielding_job_complete, + }, +}; + +/* + * Test that job_wait_unpaused() can get jobs from a paused state to + * a running state so that job_complete() can be applied (assuming the + * pause occurred due to a drain that has already been lifted). + * (This is what QMP's block-job-complete does so it can be executed + * even immediately after some other operation instated and lifted a + * drain.) + * + * To do this, run YieldingJob in an IO thread, get it into the READY + * state, then have a drained section. Before ending the section, + * acquire the context so the job will not be entered and will thus + * remain on STANDBY. + * + * Invoking job_complete() then will fail. + * + * However, job_wait_unpaused() should see the job is to be resumed, + * wait for it to be resumed, and then we can invoke job_complete() + * without error. + * + * Note that on the QMP interface, it is impossible to lock an IO + * thread before a drained section ends. In practice, the + * bdrv_drain_all_end() and the aio_context_acquire() will be + * reversed. However, that makes for worse reproducibility here: + * Sometimes, the job would no longer be in STANDBY then but already + * be started. We cannot prevent that, because the IO thread runs + * concurrently. We can only prevent it by taking the lock before + * ending the drained section, so we do that. + * + * (You can reverse the order of operations and most of the time the + * test will pass, but sometimes the assert(status == STANDBY) will + * fail.) + */ +static void test_complete_in_standby(void) +{ + BlockBackend *blk; + IOThread *iothread; + AioContext *ctx; + Job *job; + BlockJob *bjob; + Error *local_err = NULL; + + /* Create a test drive, move it to an IO thread */ + blk = create_blk(NULL); + iothread = iothread_new(); + + ctx = iothread_get_aio_context(iothread); + blk_set_aio_context(blk, ctx, &error_abort); + + /* Create our test job */ + bjob = mk_job(blk, "job", &test_yielding_driver, true, + JOB_MANUAL_FINALIZE | JOB_MANUAL_DISMISS); + job = &bjob->job; + assert(job->status == JOB_STATUS_CREATED); + + /* Wait for the job to become READY */ + job_start(job); + aio_context_acquire(ctx); + AIO_WAIT_WHILE(ctx, job->status != JOB_STATUS_READY); + aio_context_release(ctx); + + /* Begin the drained section, pausing the job */ + bdrv_drain_all_begin(); + assert(job->status == JOB_STATUS_STANDBY); + /* Lock the IO thread to prevent the job from being run */ + aio_context_acquire(ctx); + /* This will schedule the job to resume it */ + bdrv_drain_all_end(); + + /* But the job cannot run, so it will remain on standby */ + assert(job->status == JOB_STATUS_STANDBY); + + /* A job on standby cannot be completed */ + job_complete(job, &local_err); + assert(local_err != NULL); + error_free(local_err); + local_err = NULL; + + /* + * But waiting for it and then completing it should work. + * (This is what qmp_block_job_complete() does.) + */ + job_wait_unpaused(job, &error_abort); + job_complete(job, &error_abort); + + /* The test is done now, clean up. */ + job_finish_sync(job, NULL, &error_abort); + assert(job->status == JOB_STATUS_PENDING); + + job_finalize(job, &error_abort); + assert(job->status == JOB_STATUS_CONCLUDED); + + job_dismiss(&job, &error_abort); + + destroy_blk(blk); + aio_context_release(ctx); + iothread_join(iothread); +} + int main(int argc, char **argv) { qemu_init_main_loop(&error_abort); @@ -389,5 +528,6 @@ int main(int argc, char **argv) g_test_add_func("/blockjob/cancel/standby", test_cancel_standby); g_test_add_func("/blockjob/cancel/pending", test_cancel_pending); g_test_add_func("/blockjob/cancel/concluded", test_cancel_concluded); + g_test_add_func("/blockjob/complete_in_standby", test_complete_in_standby); return g_test_run(); }