From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 24C9CC433E4 for ; Sat, 22 Aug 2020 03:30:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01DA8214F1 for ; Sat, 22 Aug 2020 03:30:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nJqynmkO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727043AbgHVDag (ORCPT ); Fri, 21 Aug 2020 23:30:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726639AbgHVDaf (ORCPT ); Fri, 21 Aug 2020 23:30:35 -0400 Received: from mail-yb1-xb42.google.com (mail-yb1-xb42.google.com [IPv6:2607:f8b0:4864:20::b42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E44CBC061573; Fri, 21 Aug 2020 20:30:34 -0700 (PDT) Received: by mail-yb1-xb42.google.com with SMTP id x2so2093832ybf.12; Fri, 21 Aug 2020 20:30:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=rwXBsAtmVDX+ECduRnQm34azFTvTIJrAjbNmRhPqbx8=; b=nJqynmkOMpMJ6z8CbAoJrBvIjjZh29RE5TqYgfsZApVbt9WpdYhYcQ0B/Vsyfm4eEG nOpaYodc9nofw7PlCFjk+fyHJe5lRBEhwqEnxiFxhG/J2prejlt5QsfyAde0XyKUqvUc kG2WWD3+d3CSzV4YlAfVu/GX7lyUKBIwFKwSuSBvKo8sBEvgzNsUzrbBT2HX53BVZ+D0 m+g/ZtjfGBezonRB+7v2bZVlM05y3Hq4erQamuKEw+5SEoH5OfsRd59R6FcGXuGbTvO7 tED6K+BdlRG/X2kiITrnAMM0R22mNh3Ab2FwBRIiy20vb4D5eWOtzsP0/dSZjRRu23QB BKrg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=rwXBsAtmVDX+ECduRnQm34azFTvTIJrAjbNmRhPqbx8=; b=D8rTvp3+pOjenGlWOj0XiXTVg7U0CWPGkUpsGNwUMIxjWs7aPBDkN0DSj3x4ATe/0H Rk68GZ3Qz6BJvjavyCCecP4eoWKtl44bi2bmsqCLBRiI/Rb7PoiuNI1oK2VXDiek+tOe +CnvoSFeCet3yk5W+YWiC83Ms0LhPhYMo4xsS4xqM/ZmfgAJY9v33wc5gxN1vg+PKF3Z A+N5QboT23r648nWeoN7pVkK8FHxINr3tsvdyvSxgGcsOu1yeVjMmcx3NRY0TRZYh3X1 3O0Zm5gfhAUvIOBYz53mJlwqV57sYMH8ddrbNwkXe2rzhO5GF67nbCKAsw24UYSv7/kX NaRg== X-Gm-Message-State: AOAM532Ugo4kYTIbx24ydv9D39ZuQR5Ya0I/Ohl51k6iwzewk6WPQ6GT yd5oJma/CbaMGxbQJh9cMmoEvWD6gf1iLsL21pI= X-Google-Smtp-Source: ABdhPJx/UHOJZH9k2JWKEiMFa6Ij5s665WrbECXeOpshL/BqF3E5bQJqt7pAH2LrqjYs5AqmhcWu0HGXghqve+2wvPI= X-Received: by 2002:a25:84cd:: with SMTP id x13mr7616141ybm.425.1598067034159; Fri, 21 Aug 2020 20:30:34 -0700 (PDT) MIME-Version: 1.0 References: <20200819224030.1615203-1-haoluo@google.com> <20200819224030.1615203-9-haoluo@google.com> In-Reply-To: <20200819224030.1615203-9-haoluo@google.com> From: Andrii Nakryiko Date: Fri, 21 Aug 2020 20:30:22 -0700 Message-ID: Subject: Re: [PATCH bpf-next v1 8/8] bpf/selftests: Test for bpf_per_cpu_ptr() To: Hao Luo Cc: Networking , bpf , open list , "open list:KERNEL SELFTEST FRAMEWORK" , Shuah Khan , Alexei Starovoitov , Andrii Nakryiko , Daniel Borkmann , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Quentin Monnet , Steven Rostedt , Ingo Molnar , Andrey Ignatov , Jakub Sitnicki Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 19, 2020 at 3:42 PM Hao Luo wrote: > > Test bpf_per_cpu_ptr(). Test two paths in the kernel. If the base > pointer points to a struct, the returned reg is of type PTR_TO_BTF_ID. > Direct pointer dereference can be applied on the returned variable. > If the base pointer isn't a struct, the returned reg is of type > PTR_TO_MEM, which also supports direct pointer dereference. > > Signed-off-by: Hao Luo > --- Acked-by: Andrii Nakryiko > .../testing/selftests/bpf/prog_tests/ksyms_btf.c | 4 ++++ > .../testing/selftests/bpf/progs/test_ksyms_btf.c | 15 ++++++++++++++- > 2 files changed, 18 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c b/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c > index 1dad61ba7e99..bdedd4a76b42 100644 > --- a/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c > +++ b/tools/testing/selftests/bpf/prog_tests/ksyms_btf.c > @@ -71,6 +71,10 @@ void test_ksyms_btf(void) > "got %llu, exp %llu\n", data->out__runqueues, runqueues_addr); > CHECK(data->out__bpf_prog_active != bpf_prog_active_addr, "bpf_prog_active", > "got %llu, exp %llu\n", data->out__bpf_prog_active, bpf_prog_active_addr); > + CHECK(data->out__rq_cpu != 1, "rq_cpu", > + "got %u, exp %u\n", data->out__rq_cpu, 1); > + CHECK(data->out__process_counts == -1, "process_counts", > + "got %lu, exp != -1", data->out__process_counts); > > cleanup: > test_ksyms_btf__destroy(skel); > diff --git a/tools/testing/selftests/bpf/progs/test_ksyms_btf.c b/tools/testing/selftests/bpf/progs/test_ksyms_btf.c > index e04e31117f84..78cf1ebb753d 100644 > --- a/tools/testing/selftests/bpf/progs/test_ksyms_btf.c > +++ b/tools/testing/selftests/bpf/progs/test_ksyms_btf.c > @@ -7,16 +7,29 @@ > > __u64 out__runqueues = -1; > __u64 out__bpf_prog_active = -1; > +__u32 out__rq_cpu = -1; > +unsigned long out__process_counts = -1; try to not use long for variables, it is 32-bit integer in user-space but always 64-bit in BPF. This causes problems when using skeleton on 32-bit architecture. > > -extern const struct rq runqueues __ksym; /* struct type global var. */ > +extern const struct rq runqueues __ksym; /* struct type percpu var. */ > extern const int bpf_prog_active __ksym; /* int type global var. */ > +extern const unsigned long process_counts __ksym; /* int type percpu var. */ > > SEC("raw_tp/sys_enter") > int handler(const void *ctx) > { > + struct rq *rq; > + unsigned long *count; > + > out__runqueues = (__u64)&runqueues; > out__bpf_prog_active = (__u64)&bpf_prog_active; > > + rq = (struct rq *)bpf_per_cpu_ptr(&runqueues, 1); > + if (rq) > + out__rq_cpu = rq->cpu; this is awesome! Are there any per-cpu variables that are arrays? Would be nice to test those too. > + count = (unsigned long *)bpf_per_cpu_ptr(&process_counts, 1); > + if (count) > + out__process_counts = *count; > + > return 0; > } > > -- > 2.28.0.220.ged08abb693-goog >