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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33ED6C433EF for ; Mon, 14 Mar 2022 17:29:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243420AbiCNRaX (ORCPT ); Mon, 14 Mar 2022 13:30:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229899AbiCNRaT (ORCPT ); Mon, 14 Mar 2022 13:30:19 -0400 Received: from mail-lj1-f172.google.com (mail-lj1-f172.google.com [209.85.208.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55979DEB6; Mon, 14 Mar 2022 10:29:09 -0700 (PDT) Received: by mail-lj1-f172.google.com with SMTP id h11so22992523ljb.2; Mon, 14 Mar 2022 10:29:09 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wluxvZZRX4EKbcVvJ/eg3d1hoy/ZEcP65mxSGZfR8b8=; b=XbwNDwKpXgp1ZuRwvwpoko54IbbMOYB3f1jXrHsKFNnutQZZNr2zneAW2SgB6xN+qn dN/hzwHJFHB8afHyFrbl6J74UeRKU2KkqC3f/GBNuktY0xYCeR4+UNEToPpvnZ9YW9ut nMvRm/eRguVIFYH9ghX9fnnHD9GVQU8Aek6vb1TPx1aD5nsRHeczjDx+47RaQ6MBYzIo SlFGtgi70yQItdbHaJWwlzzaOfJDoxA5O7tPZ64YFiH9b9pUMIYvTqVgzBvwQLzzSF40 g5VEGw3PqIabA8fMo6+FxNlf2JAQQoP+uUje1WomJBKVCFGx4rjHN2OjsCwu+XydO38h /5qg== X-Gm-Message-State: AOAM532HCYcmQI0A876T+uTQh98UvI4mVZVv+I+FC7PXcKF+4aQNX6MF TaLgdh/H1oMxo6EP0j84dWRVE6mm3DY+H/e87M0= X-Google-Smtp-Source: ABdhPJyDjw6SAJ1pG95ESM8cb9VMKIADALppkjSv7LXf4LGBo6GrfONjwX+IxH0EO7+FzyBugxipqjskb8vqlGjBREY= X-Received: by 2002:a05:651c:1051:b0:247:ea0d:a57c with SMTP id x17-20020a05651c105100b00247ea0da57cmr14118926ljm.204.1647278947501; Mon, 14 Mar 2022 10:29:07 -0700 (PDT) MIME-Version: 1.0 References: <20220310082202.1229345-1-namhyung@kernel.org> <20220310082202.1229345-2-namhyung@kernel.org> In-Reply-To: From: Namhyung Kim Date: Mon, 14 Mar 2022 10:28:56 -0700 Message-ID: Subject: Re: [PATCH 2/2] bpf/selftests: Test skipping stacktrace To: Andrii Nakryiko Cc: Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Networking , bpf , LKML , Arnaldo Carvalho de Melo , Peter Zijlstra , Eugene Loh , Hao Luo Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On Fri, Mar 11, 2022 at 2:23 PM Andrii Nakryiko wrote: > > On Thu, Mar 10, 2022 at 12:22 AM Namhyung Kim wrote: > > +SEC("tracepoint/sched/sched_switch") > > +int oncpu(struct sched_switch_args *ctx) > > +{ > > + __u32 max_len = TEST_STACK_DEPTH * sizeof(__u64); > > + __u32 key = 0, val = 0, *value_p; > > + __u64 *stack_p; > > + > > please also add filtering by PID to avoid interference from other > selftests when run in parallel mode Will do! Thanks, Namhyung > > > + value_p = bpf_map_lookup_elem(&control_map, &key); > > + if (value_p && *value_p) > > + return 0; /* skip if non-zero *value_p */ > > + > > + /* it should allow skipping whole buffer size entries */ > > + key = bpf_get_stackid(ctx, &stackmap, TEST_STACK_DEPTH); > > + if ((int)key >= 0) { > > + /* The size of stackmap and stack_amap should be the same */ > > + bpf_map_update_elem(&stackid_hmap, &key, &val, 0); > > + stack_p = bpf_map_lookup_elem(&stack_amap, &key); > > + if (stack_p) { > > + bpf_get_stack(ctx, stack_p, max_len, TEST_STACK_DEPTH); > > + /* it wrongly skipped all the entries and filled zero */ > > + if (stack_p[0] == 0) > > + failed = 1; > > + } > > + } else if ((int)key == -14/*EFAULT*/) { > > + /* old kernel doesn't support skipping that many entries */ > > + failed = 2; > > + } > > + > > + return 0; > > +} > > + > > +char _license[] SEC("license") = "GPL"; > > -- > > 2.35.1.723.g4982287a31-goog > >