[bpf-next,2/2] selftests/bpf: Augment send_signal test with remote signaling

Message ID	20240724113944.75977-2-puranjay@kernel.org (mailing list archive)
State	Handled Elsewhere
Headers	show Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C913D157491; Wed, 24 Jul 2024 11:40:03 +0000 (UTC) From: Puranjay Mohan <puranjay@kernel.org> To: Alexei Starovoitov <ast@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>, Andrii Nakryiko <andrii@kernel.org>, Martin KaFai Lau <martin.lau@linux.dev>, Eduard Zingerman <eddyz87@gmail.com>, Song Liu <song@kernel.org>, Yonghong Song <yonghong.song@linux.dev>, John Fastabend <john.fastabend@gmail.com>, KP Singh <kpsingh@kernel.org>, Stanislav Fomichev <sdf@fomichev.me>, Hao Luo <haoluo@google.com>, Jiri Olsa <jolsa@kernel.org>, Matt Bobrowski <mattbobrowski@google.com>, Steven Rostedt <rostedt@goodmis.org>, Masami Hiramatsu <mhiramat@kernel.org>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, Puranjay Mohan <puranjay12@gmail.com>, Abhishek Chauhan <quic_abchauha@quicinc.com>, bpf@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH bpf-next 2/2] selftests/bpf: Augment send_signal test with remote signaling Date: Wed, 24 Jul 2024 11:39:44 +0000 Message-Id: <20240724113944.75977-2-puranjay@kernel.org> In-Reply-To: <20240724113944.75977-1-puranjay@kernel.org> References: <20240724113944.75977-1-puranjay@kernel.org> Precedence: bulk MIME-Version: 1.0 Content-Transfer-Encoding: 8bit
Series	[bpf-next,1/2] bpf: implement bpf_send_signal_pid/tgid() helpers \| expand [bpf-next,1/2] bpf: implement bpf_send_signal_pid/tgid() helpers [bpf-next,2/2] selftests/bpf: Augment send_signal test with remote signaling

diff --git a/tools/testing/selftests/bpf/prog_tests/send_signal.c b/tools/testing/selftests/bpf/prog_tests/send_signal.c index 6cc69900b310..a8392dfc69e2 100644 --- a/tools/testing/selftests/bpf/prog_tests/send_signal.c +++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c @@ -12,13 +12,15 @@ static void sigusr1_handler(int signum) } static void test_send_signal_common(struct perf_event_attr *attr, - bool signal_thread) + bool signal_thread, bool remote) { struct test_send_signal_kern *skel; int pipe_c2p[2], pipe_p2c[2]; int err = -1, pmu_fd = -1; + volatile int j = 0; char buf[256]; pid_t pid; + int old_prio; if (!ASSERT_OK(pipe(pipe_c2p), "pipe_c2p")) return; @@ -39,9 +41,6 @@ static void test_send_signal_common(struct perf_event_attr *attr, } if (pid == 0) { - int old_prio; - volatile int j = 0; - /* install signal handler and notify parent */ ASSERT_NEQ(signal(SIGUSR1, sigusr1_handler), SIG_ERR, "signal"); @@ -52,10 +51,12 @@ static void test_send_signal_common(struct perf_event_attr *attr, * that if an interrupt happens, the underlying task * is this process. */ - errno = 0; - old_prio = getpriority(PRIO_PROCESS, 0); - ASSERT_OK(errno, "getpriority"); - ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority"); + if (!remote) { + errno = 0; + old_prio = getpriority(PRIO_PROCESS, 0); + ASSERT_OK(errno, "getpriority"); + ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority"); + } /* notify parent signal handler is installed */ ASSERT_EQ(write(pipe_c2p[1], buf, 1), 1, "pipe_write"); @@ -66,9 +67,12 @@ static void test_send_signal_common(struct perf_event_attr *attr, /* wait a little for signal handler */ for (int i = 0; i < 1000000000 && !sigusr1_received; i++) { j /= i + j + 1; - if (!attr) - /* trigger the nanosleep tracepoint program. */ - usleep(1); + if (remote) + sleep(1); + else + if (!attr) + /* trigger the nanosleep tracepoint program. */ + usleep(1); } buf[0] = sigusr1_received ? '2' : '0'; @@ -79,7 +83,8 @@ static void test_send_signal_common(struct perf_event_attr *attr, ASSERT_EQ(read(pipe_p2c[0], buf, 1), 1, "pipe_read"); /* restore the old priority */ - ASSERT_OK(setpriority(PRIO_PROCESS, 0, old_prio), "setpriority"); + if (!remote) + ASSERT_OK(setpriority(PRIO_PROCESS, 0, old_prio), "setpriority"); close(pipe_c2p[1]); close(pipe_p2c[0]); @@ -93,6 +98,17 @@ static void test_send_signal_common(struct perf_event_attr *attr, if (!ASSERT_OK_PTR(skel, "skel_open_and_load")) goto skel_open_load_failure; + /* boost with a high priority so we got a higher chance + * that if an interrupt happens, the underlying task + * is this process. + */ + if (remote) { + errno = 0; + old_prio = getpriority(PRIO_PROCESS, 0); + ASSERT_OK(errno, "getpriority"); + ASSERT_OK(setpriority(PRIO_PROCESS, 0, -20), "setpriority"); + } + if (!attr) { err = test_send_signal_kern__attach(skel); if (!ASSERT_OK(err, "skel_attach")) { @@ -100,8 +116,12 @@ static void test_send_signal_common(struct perf_event_attr *attr, goto destroy_skel; } } else { - pmu_fd = syscall(__NR_perf_event_open, attr, pid, -1 /* cpu */, - -1 /* group id */, 0 /* flags */); + if (!remote) + pmu_fd = syscall(__NR_perf_event_open, attr, pid, -1 /* cpu */, + -1 /* group id */, 0 /* flags */); + else + pmu_fd = syscall(__NR_perf_event_open, attr, getpid(), -1 /* cpu */, + -1 /* group id */, 0 /* flags */); if (!ASSERT_GE(pmu_fd, 0, "perf_event_open")) { err = -1; goto destroy_skel; @@ -119,11 +139,30 @@ static void test_send_signal_common(struct perf_event_attr *attr, /* trigger the bpf send_signal */ skel->bss->signal_thread = signal_thread; skel->bss->sig = SIGUSR1; - skel->bss->pid = pid; + if (!remote) { + skel->bss->target_pid = 0; + skel->bss->pid = pid; + } else { + skel->bss->target_pid = pid; + skel->bss->pid = getpid(); + } /* notify child that bpf program can send_signal now */ ASSERT_EQ(write(pipe_p2c[1], buf, 1), 1, "pipe_write"); + /* For the remote test, the BPF program is triggered from this + * process but the other process/thread is signaled. + */ + if (remote) { + if (!attr) { + for (int i = 0; i < 10; i++) + usleep(1); + } else { + for (int i = 0; i < 100000000; i++) + j /= i + 1; + } + } + /* wait for result */ err = read(pipe_c2p[0], buf, 1); if (!ASSERT_GE(err, 0, "reading pipe")) @@ -142,18 +181,21 @@ static void test_send_signal_common(struct perf_event_attr *attr, close(pmu_fd); destroy_skel: test_send_signal_kern__destroy(skel); + /* restore the old priority */ + if (remote) + ASSERT_OK(setpriority(PRIO_PROCESS, 0, old_prio), "setpriority"); skel_open_load_failure: close(pipe_c2p[0]); close(pipe_p2c[1]); wait(NULL); } -static void test_send_signal_tracepoint(bool signal_thread) +static void test_send_signal_tracepoint(bool signal_thread, bool remote) { - test_send_signal_common(NULL, signal_thread); + test_send_signal_common(NULL, signal_thread, remote); } -static void test_send_signal_perf(bool signal_thread) +static void test_send_signal_perf(bool signal_thread, bool remote) { struct perf_event_attr attr = { .freq = 1, @@ -162,10 +204,10 @@ static void test_send_signal_perf(bool signal_thread) .config = PERF_COUNT_SW_CPU_CLOCK, }; - test_send_signal_common(&attr, signal_thread); + test_send_signal_common(&attr, signal_thread, remote); } -static void test_send_signal_nmi(bool signal_thread) +static void test_send_signal_nmi(bool signal_thread, bool remote) { struct perf_event_attr attr = { .sample_period = 1, @@ -191,21 +233,35 @@ static void test_send_signal_nmi(bool signal_thread) close(pmu_fd); } - test_send_signal_common(&attr, signal_thread); + test_send_signal_common(&attr, signal_thread, remote); } void test_send_signal(void) { if (test__start_subtest("send_signal_tracepoint")) - test_send_signal_tracepoint(false); + test_send_signal_tracepoint(false, false); if (test__start_subtest("send_signal_perf")) - test_send_signal_perf(false); + test_send_signal_perf(false, false); if (test__start_subtest("send_signal_nmi")) - test_send_signal_nmi(false); + test_send_signal_nmi(false, false); if (test__start_subtest("send_signal_tracepoint_thread")) - test_send_signal_tracepoint(true); + test_send_signal_tracepoint(true, false); if (test__start_subtest("send_signal_perf_thread")) - test_send_signal_perf(true); + test_send_signal_perf(true, false); if (test__start_subtest("send_signal_nmi_thread")) - test_send_signal_nmi(true); + test_send_signal_nmi(true, false); + + /* Signal remote thread and thread group */ + if (test__start_subtest("send_signal_tracepoint_remote")) + test_send_signal_tracepoint(false, true); + if (test__start_subtest("send_signal_perf_remote")) + test_send_signal_perf(false, true); + if (test__start_subtest("send_signal_nmi_remote")) + test_send_signal_nmi(false, true); + if (test__start_subtest("send_signal_tracepoint_thread_remote")) + test_send_signal_tracepoint(true, true); + if (test__start_subtest("send_signal_perf_thread_remote")) + test_send_signal_perf(true, true); + if (test__start_subtest("send_signal_nmi_thread_remote")) + test_send_signal_nmi(true, true); } diff --git a/tools/testing/selftests/bpf/progs/test_send_signal_kern.c b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c index 92354cd72044..fd6c055377ae 100644 --- a/tools/testing/selftests/bpf/progs/test_send_signal_kern.c +++ b/tools/testing/selftests/bpf/progs/test_send_signal_kern.c @@ -4,7 +4,7 @@ #include <linux/version.h> #include <bpf/bpf_helpers.h> -__u32 sig = 0, pid = 0, status = 0, signal_thread = 0; +__u32 sig = 0, pid = 0, status = 0, signal_thread = 0, target_pid = 0; static __always_inline int bpf_send_signal_test(void *ctx) { @@ -14,10 +14,17 @@ static __always_inline int bpf_send_signal_test(void *ctx) return 0; if ((bpf_get_current_pid_tgid() >> 32) == pid) { - if (signal_thread) - ret = bpf_send_signal_thread(sig); - else - ret = bpf_send_signal(sig); + if (signal_thread) { + if (target_pid != 0) + ret = bpf_send_signal_pid(sig, target_pid); + else + ret = bpf_send_signal_thread(sig); + } else { + if (target_pid != 0) + ret = bpf_send_signal_tgid(sig, target_pid); + else + ret = bpf_send_signal(sig); + } if (ret == 0) status = 1; }

[bpf-next,2/2] selftests/bpf: Augment send_signal test with remote signaling

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