From patchwork Thu Apr 8 10:36:05 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marco Elver X-Patchwork-Id: 417768 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=-26.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 E9588C43460 for ; Thu, 8 Apr 2021 10:37:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BEBC061158 for ; Thu, 8 Apr 2021 10:37:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231337AbhDHKiE (ORCPT ); Thu, 8 Apr 2021 06:38:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231366AbhDHKhh (ORCPT ); Thu, 8 Apr 2021 06:37:37 -0400 Received: from mail-ej1-x64a.google.com (mail-ej1-x64a.google.com [IPv6:2a00:1450:4864:20::64a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 53197C0613E8 for ; Thu, 8 Apr 2021 03:37:11 -0700 (PDT) Received: by mail-ej1-x64a.google.com with SMTP id h19so655602ejk.8 for ; Thu, 08 Apr 2021 03:37:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=BCBGbOGg89seqk0GJ8e7eMRxQa1aJCiARfAN/gtOasU=; b=Abilg05WGGBatoHpAGoYZVInSdef9vyAP/aPw2pF3+K6u42MIhLRm1sClMALqLyj6I kI5EnTuyjZ8LEADUh38lXlk4sxI+cp7UD9DueBr/OsvTinmd4+bccadauq8EMeeKIqAK f89MQh18O3shRje614FI5wkCbm+h/0mDdprFhqIcYRdaNrUNPDUTalQztZqNugjHwf5O V2OlsC6C+pK99dr65nYJnXHeLK7lej5LUlLxgO60R7QglxTPDi9SZR9N5tDgEp99PkQ3 auQhwe2nl3OhR/pA40i2wjWK3OdPNtUg4GbCFBsXF0adEBCi/kZjpEQpSipTfv85BmiL y0IQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=BCBGbOGg89seqk0GJ8e7eMRxQa1aJCiARfAN/gtOasU=; b=Q192mlrKbZfAJo7mViQDrlD3rYW2VfLFmHwY6Is1lAUm7knhA5mQLDCpA5dAm4jcD9 QpxgYIJY0dCTX1JSVxEMnJc7YFyQo48ZPIDp/yPukgVWYO5M+dJ8ghsyTHZjS0tLfufk 29EnKLYrTSTJbA7UMEyaDBpYBWfHu5R6Shs54u+pG17qSY0K82DQ/X5liDvjs9Y7vXvh VMmVzKBmAf6gdD0D1zNp2xZJSfLHmuznk/OWtk0QBhXx6KqtakuudyrtYdNC4kIcxtPn 96oFCPMxU+RhFSo+45NDgDBVPHl+dqz1I4wtq3VZkcZDe6yffIfR92Swe70gEsbnpnZz EX2w== X-Gm-Message-State: AOAM533wSzvWp0tfsm1QQ8fBDJl4EmDueBpP0oFSDlvVFxyMs2Y1aRZn GFVakRSsv/t9yPBwpm1tZZcAw03MPw== X-Google-Smtp-Source: ABdhPJwUyB3TxRpuM73O4rL06IetXxXvzAxviPSheqdhPNzkKUHZ7b08H4mQzxLXA3ZvtpFt3rt8pum25A== X-Received: from elver.muc.corp.google.com ([2a00:79e0:15:13:9038:bbd3:4a12:abda]) (user=elver job=sendgmr) by 2002:a17:906:ce4e:: with SMTP id se14mr9777476ejb.54.1617878229875; Thu, 08 Apr 2021 03:37:09 -0700 (PDT) Date: Thu, 8 Apr 2021 12:36:05 +0200 In-Reply-To: <20210408103605.1676875-1-elver@google.com> Message-Id: <20210408103605.1676875-11-elver@google.com> Mime-Version: 1.0 References: <20210408103605.1676875-1-elver@google.com> X-Mailer: git-send-email 2.31.0.208.g409f899ff0-goog Subject: [PATCH v4 10/10] perf test: Add basic stress test for sigtrap handling From: Marco Elver To: elver@google.com, peterz@infradead.org, alexander.shishkin@linux.intel.com, acme@kernel.org, mingo@redhat.com, jolsa@redhat.com, mark.rutland@arm.com, namhyung@kernel.org, tglx@linutronix.de Cc: glider@google.com, viro@zeniv.linux.org.uk, arnd@arndb.de, christian@brauner.io, dvyukov@google.com, jannh@google.com, axboe@kernel.dk, mascasa@google.com, pcc@google.com, irogers@google.com, oleg@redhat.com, kasan-dev@googlegroups.com, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, linux-kselftest@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Add basic stress test for sigtrap handling as a perf tool built-in test. This allows sanity checking the basic sigtrap functionality from within the perf tool. Note: A more elaborate kselftest version of this test can also be found in tools/testing/selftests/perf_events/sigtrap_threads.c. Signed-off-by: Marco Elver --- v4: * Update for new perf_event_attr::sig_data / si_perf handling. v3: * Added to series (per suggestion from Ian Rogers). --- tools/perf/tests/Build | 1 + tools/perf/tests/builtin-test.c | 5 ++ tools/perf/tests/sigtrap.c | 150 ++++++++++++++++++++++++++++++++ tools/perf/tests/tests.h | 1 + 4 files changed, 157 insertions(+) create mode 100644 tools/perf/tests/sigtrap.c diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build index 650aec19d490..a429c7a02b37 100644 --- a/tools/perf/tests/Build +++ b/tools/perf/tests/Build @@ -64,6 +64,7 @@ perf-y += parse-metric.o perf-y += pe-file-parsing.o perf-y += expand-cgroup.o perf-y += perf-time-to-tsc.o +perf-y += sigtrap.o $(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c tests/Build $(call rule_mkdir) diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c index c4b888f18e9c..28a1cb5eaa77 100644 --- a/tools/perf/tests/builtin-test.c +++ b/tools/perf/tests/builtin-test.c @@ -359,6 +359,11 @@ static struct test generic_tests[] = { .func = test__perf_time_to_tsc, .is_supported = test__tsc_is_supported, }, + { + .desc = "Sigtrap support", + .func = test__sigtrap, + .is_supported = test__wp_is_supported, /* uses wp for test */ + }, { .func = NULL, }, diff --git a/tools/perf/tests/sigtrap.c b/tools/perf/tests/sigtrap.c new file mode 100644 index 000000000000..c367cc2f64d5 --- /dev/null +++ b/tools/perf/tests/sigtrap.c @@ -0,0 +1,150 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Basic test for sigtrap support. + * + * Copyright (C) 2021, Google LLC. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#include "cloexec.h" +#include "debug.h" +#include "event.h" +#include "tests.h" +#include "../perf-sys.h" + +#define NUM_THREADS 5 + +static struct { + int tids_want_signal; /* Which threads still want a signal. */ + int signal_count; /* Sanity check number of signals received. */ + volatile int iterate_on; /* Variable to set breakpoint on. */ + siginfo_t first_siginfo; /* First observed siginfo_t. */ +} ctx; + +#define TEST_SIG_DATA (~(uint64_t)(&ctx.iterate_on)) + +static struct perf_event_attr make_event_attr(void) +{ + struct perf_event_attr attr = { + .type = PERF_TYPE_BREAKPOINT, + .size = sizeof(attr), + .sample_period = 1, + .disabled = 1, + .bp_addr = (unsigned long)&ctx.iterate_on, + .bp_type = HW_BREAKPOINT_RW, + .bp_len = HW_BREAKPOINT_LEN_1, + .inherit = 1, /* Children inherit events ... */ + .inherit_thread = 1, /* ... but only cloned with CLONE_THREAD. */ + .remove_on_exec = 1, /* Required by sigtrap. */ + .sigtrap = 1, /* Request synchronous SIGTRAP on event. */ + .sig_data = TEST_SIG_DATA, + }; + return attr; +} + +static void +sigtrap_handler(int signum __maybe_unused, siginfo_t *info, void *ucontext __maybe_unused) +{ + if (!__atomic_fetch_add(&ctx.signal_count, 1, __ATOMIC_RELAXED)) + ctx.first_siginfo = *info; + __atomic_fetch_sub(&ctx.tids_want_signal, syscall(SYS_gettid), __ATOMIC_RELAXED); +} + +static void *test_thread(void *arg) +{ + pthread_barrier_t *barrier = (pthread_barrier_t *)arg; + pid_t tid = syscall(SYS_gettid); + int i; + + pthread_barrier_wait(barrier); + + __atomic_fetch_add(&ctx.tids_want_signal, tid, __ATOMIC_RELAXED); + for (i = 0; i < ctx.iterate_on - 1; i++) + __atomic_fetch_add(&ctx.tids_want_signal, tid, __ATOMIC_RELAXED); + + return NULL; +} + +static int run_test_threads(pthread_t *threads, pthread_barrier_t *barrier) +{ + int i; + + pthread_barrier_wait(barrier); + for (i = 0; i < NUM_THREADS; i++) + TEST_ASSERT_EQUAL("pthread_join() failed", pthread_join(threads[i], NULL), 0); + + return TEST_OK; +} + +static int run_stress_test(int fd, pthread_t *threads, pthread_barrier_t *barrier) +{ + int ret; + + ctx.iterate_on = 3000; + + TEST_ASSERT_EQUAL("misfired signal?", ctx.signal_count, 0); + TEST_ASSERT_EQUAL("enable failed", ioctl(fd, PERF_EVENT_IOC_ENABLE, 0), 0); + ret = run_test_threads(threads, barrier); + TEST_ASSERT_EQUAL("disable failed", ioctl(fd, PERF_EVENT_IOC_DISABLE, 0), 0); + + TEST_ASSERT_EQUAL("unexpected sigtraps", ctx.signal_count, NUM_THREADS * ctx.iterate_on); + TEST_ASSERT_EQUAL("missing signals or incorrectly delivered", ctx.tids_want_signal, 0); + TEST_ASSERT_VAL("unexpected si_addr", ctx.first_siginfo.si_addr == &ctx.iterate_on); + TEST_ASSERT_EQUAL("unexpected si_errno", ctx.first_siginfo.si_errno, PERF_TYPE_BREAKPOINT); +#if 0 /* FIXME: test build and enable when libc's signal.h has si_perf. */ + TEST_ASSERT_VAL("unexpected si_perf", ctx.first_siginfo.si_perf == TEST_SIG_DATA); +#endif + + return ret; +} + +int test__sigtrap(struct test *test __maybe_unused, int subtest __maybe_unused) +{ + struct perf_event_attr attr = make_event_attr(); + struct sigaction action = {}; + struct sigaction oldact; + pthread_t threads[NUM_THREADS]; + pthread_barrier_t barrier; + int i, fd, ret = TEST_FAIL; + + pthread_barrier_init(&barrier, NULL, NUM_THREADS + 1); + + action.sa_flags = SA_SIGINFO | SA_NODEFER; + action.sa_sigaction = sigtrap_handler; + sigemptyset(&action.sa_mask); + if (sigaction(SIGTRAP, &action, &oldact)) { + pr_debug("FAILED sigaction()\n"); + goto out; + } + + fd = sys_perf_event_open(&attr, 0, -1, -1, perf_event_open_cloexec_flag()); + if (fd < 0) { + pr_debug("FAILED sys_perf_event_open()\n"); + goto out_restore_sigaction; + } + + for (i = 0; i < NUM_THREADS; i++) { + if (pthread_create(&threads[i], NULL, test_thread, &barrier)) { + pr_debug("FAILED pthread_create()"); + goto out_close_perf_event; + } + } + + ret = run_stress_test(fd, threads, &barrier); + +out_close_perf_event: + close(fd); +out_restore_sigaction: + sigaction(SIGTRAP, &oldact, NULL); +out: + pthread_barrier_destroy(&barrier); + return ret; +} diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h index b85f005308a3..c3f2e2ecbfd6 100644 --- a/tools/perf/tests/tests.h +++ b/tools/perf/tests/tests.h @@ -127,6 +127,7 @@ int test__parse_metric(struct test *test, int subtest); int test__pe_file_parsing(struct test *test, int subtest); int test__expand_cgroup_events(struct test *test, int subtest); int test__perf_time_to_tsc(struct test *test, int subtest); +int test__sigtrap(struct test *test, int subtest); bool test__bp_signal_is_supported(void); bool test__bp_account_is_supported(void);