Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0DBD0C05027 for ; Fri, 3 Feb 2023 20:01:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233560AbjBCUBq (ORCPT ); Fri, 3 Feb 2023 15:01:46 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50562 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229782AbjBCUBn (ORCPT ); Fri, 3 Feb 2023 15:01:43 -0500 Received: from mail-pf1-x449.google.com (mail-pf1-x449.google.com [IPv6:2607:f8b0:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35D2DA6C07 for ; Fri, 3 Feb 2023 12:01:42 -0800 (PST) Received: by mail-pf1-x449.google.com with SMTP id z7-20020aa79587000000b00593f19705d5so3207440pfj.10 for ; Fri, 03 Feb 2023 12:01:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:from:subject:message-id:mime-version:date:from:to:cc:subject :date:message-id:reply-to; bh=JqXBZCshocKpxm4gEZMlbqbtIQK38/N6xcknjdoOafE=; b=KPkJ1C/qL+FzGJYKo7gZ9K8p9Rgy19fakC/0EXy5pbZ9pd7P+QiTu0iD0dhI9UbSJE ug9LrnGhUIFtdtwIQyckSPbuQQe3jbw9Oy21pU+za+tjCpzjDq73hVOchBdcN8PCAmAl 0NnMek0tb/OU0RvhfHWeFcOJFawcLGLO6fO5Rfq87athdWEN4bAChRYsL/ETwxqRQGyd IE7CYS156co+zXWT9O+hzT1mhN2LlMFYOVuwTia/t5apG1VfKGhqHH7RPEs3uhotz9ry x1RHZAI3i6wb4BpMmyDiepFohU0aMUssXeL10kjpkWU9e2cXoF49WhvcmpysMm1/+eK+ kR1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:from:subject:message-id:mime-version:date:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=JqXBZCshocKpxm4gEZMlbqbtIQK38/N6xcknjdoOafE=; b=4fl4VMtzNvkDShE82fMYsgtH7hnp/7katEPTc+cVqft8htTMEYbnrPEYda289l8fVp UvdhgO62OpWtLmOU+k9Lxiy3GU3MzQt4MVf9rAE2Tbw9nym4JJkRWeyx3pZQm1NDgyfP AnHjKHP2ITrv4NCEYXe6sFgDoPYzKHYCdUSHyiyrYUA3mUCgXdFwprSdWTZqrC/AHBbQ y4FmkoOIQBlvSeyQKevGSrGOa3D3xEcMhaWWoAM7mWlD3Ib7K/uqfSt8k9y9T83satfJ opXNOpWxBmT2G49yrWu15cbfNOrpIsi56YlDYeg7z/r/AUlCTd52ST41g8OZbNzPPg9q BIIQ== X-Gm-Message-State: AO0yUKUUWmh+ewpumVop5yAkx/tD06xzKvIdR37GMjsxeccEpVjZ3UEO hX3yCFemvAWO1sES89SRrS9r79x3oSZKohrF25nNF4sJUa3r2q3MxnBxWJhbNj9VYKi2ooHgbXh s56RWxHgHAp6+1O1QsNeC8kw1qQ8sRG6AcoH4bp6FwIOXJYIP7naweau1kcrNP64AfjQdat0= X-Google-Smtp-Source: AK7set8JPnZxVFCHbB1AGGUevN9knwDSex9toGJJvf4HG1+oZw8YNgPoQrhwBtORgREelhgPERfgo3LM8er1 X-Received: from jstultz-noogler2.c.googlers.com ([fda3:e722:ac3:cc00:24:72f4:c0a8:600]) (user=jstultz job=sendgmr) by 2002:a17:902:8649:b0:194:706a:ad18 with SMTP id y9-20020a170902864900b00194706aad18mr2662260plt.18.1675454501477; Fri, 03 Feb 2023 12:01:41 -0800 (PST) Date: Fri, 3 Feb 2023 20:01:35 +0000 Mime-Version: 1.0 X-Mailer: git-send-email 2.39.1.519.gcb327c4b5f-goog Message-ID: <20230203200138.3872873-1-jstultz@google.com> Subject: [PATCH v2 1/4] locktorture: Add nested_[un]lock() hooks and nlocks parameter From: John Stultz To: LKML Cc: John Stultz , Davidlohr Bueso , "Paul E. McKenney" , Josh Triplett , Joel Fernandes , Juri Lelli , Valentin Schneider , Dietmar Eggemann Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In order ot extend locktorture to support lock nesting, add nested_lock() and nested_unlock() hooks to the torture ops. These take a 32bit lockset mask which is generated at random, so some number of locks will be taken before the main lock is taken and released afterwards. Additionally, add nlocks module parameter to allow specifying the number of nested locks to be used. This has been helpful to uncover issues in the proxy-exec series development. This was inspired by locktorture extensions originally implemented by Connor O'Brien, for stress testing the proxy-execution series: https://lore.kernel.org/lkml/20221003214501.2050087-12-connoro@google.com/ Comments or feedback would be greatly appreciated! Cc: Davidlohr Bueso Cc: "Paul E. McKenney" Cc: Josh Triplett Cc: Joel Fernandes Cc: Juri Lelli Cc: Valentin Schneider Cc: Dietmar Eggemann Signed-off-by: John Stultz --- kernel/locking/locktorture.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 9c2fb613a55d..f4fbd3194654 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -48,6 +48,9 @@ torture_param(int, stat_interval, 60, torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable"); torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); +torture_param(int, nlocks, 0, "Number of nested locks"); +/* Going much higher trips "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!" errors */ +#define MAX_LOCKS 8 static char *torture_type = "spin_lock"; module_param(torture_type, charp, 0444); @@ -76,10 +79,12 @@ static void lock_torture_cleanup(void); struct lock_torture_ops { void (*init)(void); void (*exit)(void); + int (*nested_lock)(int tid, u32 lockset); int (*writelock)(int tid); void (*write_delay)(struct torture_random_state *trsp); void (*task_boost)(struct torture_random_state *trsp); void (*writeunlock)(int tid); + void (*nested_unlock)(int tid, u32 lockset); int (*readlock)(int tid); void (*read_delay)(struct torture_random_state *trsp); void (*readunlock)(int tid); @@ -669,6 +674,7 @@ static int lock_torture_writer(void *arg) struct lock_stress_stats *lwsp = arg; int tid = lwsp - cxt.lwsa; DEFINE_TORTURE_RANDOM(rand); + u32 lockset_mask; VERBOSE_TOROUT_STRING("lock_torture_writer task started"); set_user_nice(current, MAX_NICE); @@ -677,7 +683,10 @@ static int lock_torture_writer(void *arg) if ((torture_random(&rand) & 0xfffff) == 0) schedule_timeout_uninterruptible(1); + lockset_mask = torture_random(&rand); cxt.cur_ops->task_boost(&rand); + if (cxt.cur_ops->nested_lock) + cxt.cur_ops->nested_lock(tid, lockset_mask); cxt.cur_ops->writelock(tid); if (WARN_ON_ONCE(lock_is_write_held)) lwsp->n_lock_fail++; @@ -690,6 +699,8 @@ static int lock_torture_writer(void *arg) lock_is_write_held = false; WRITE_ONCE(last_lock_release, jiffies); cxt.cur_ops->writeunlock(tid); + if (cxt.cur_ops->nested_unlock) + cxt.cur_ops->nested_unlock(tid, lockset_mask); stutter_wait("lock_torture_writer"); } while (!torture_must_stop()); @@ -830,11 +841,11 @@ lock_torture_print_module_parms(struct lock_torture_ops *cur_ops, const char *tag) { pr_alert("%s" TORTURE_FLAG - "--- %s%s: nwriters_stress=%d nreaders_stress=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n", + "--- %s%s: nwriters_stress=%d nreaders_stress=%d nlocks=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n", torture_type, tag, cxt.debug_lock ? " [debug]": "", - cxt.nrealwriters_stress, cxt.nrealreaders_stress, stat_interval, - verbose, shuffle_interval, stutter, shutdown_secs, - onoff_interval, onoff_holdoff); + cxt.nrealwriters_stress, cxt.nrealreaders_stress, nlocks, + stat_interval, verbose, shuffle_interval, stutter, + shutdown_secs, onoff_interval, onoff_holdoff); } static void lock_torture_cleanup(void) @@ -1053,6 +1064,10 @@ static int __init lock_torture_init(void) } } + /* cap nlocks to MAX_LOCKS */ + if (nlocks > MAX_LOCKS) + nlocks = MAX_LOCKS; + if (cxt.cur_ops->readlock) { reader_tasks = kcalloc(cxt.nrealreaders_stress, sizeof(reader_tasks[0]), -- 2.39.1.519.gcb327c4b5f-goog