From patchwork Thu Aug 27 22:01:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexei Starovoitov X-Patchwork-Id: 261827 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=-6.6 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=no 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 42B8AC433E6 for ; Thu, 27 Aug 2020 22:01:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1FCBE20848 for ; Thu, 27 Aug 2020 22:01:20 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="K7Xv9kWv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727093AbgH0WBT (ORCPT ); Thu, 27 Aug 2020 18:01:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43968 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726147AbgH0WBT (ORCPT ); Thu, 27 Aug 2020 18:01:19 -0400 Received: from mail-pf1-x443.google.com (mail-pf1-x443.google.com [IPv6:2607:f8b0:4864:20::443]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C88BAC061264; Thu, 27 Aug 2020 15:01:18 -0700 (PDT) Received: by mail-pf1-x443.google.com with SMTP id t9so4548022pfq.8; Thu, 27 Aug 2020 15:01:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=ZHhZPmfMM8w4lA9baRiaWiLPa66wAuHgYphisGjv/W4=; b=K7Xv9kWvuFugMHsINEndmO32Pt+zZxvKfOy4qyNucheUJ99TbqWOm8fXweX2PWjcsE yiw9yhlGwrFIvzBJjW6QJXQOThJxWBj4kpXCfqTTOviCWL//5Md+FquUMfrpBqJFjPaz mvhbG4DHd9WPp5ZD6oSRkPKXnj+7R1jp3Jk9VvG1YWVsbgHiQ3TuiY+UDyqU1DPJTpTw uaIkArUK3J8dvN4eKxqElHoxX9WkfFyx791BgEG8hKmiMoNU6YcxyhxKbTefuVNQDnvu IMYyosAWML+tz4tc+/YH9iD2j+APimI96s3CrflF8ccGUevfaKw9+EMtwwH7pOoJ2t/1 1CWg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=ZHhZPmfMM8w4lA9baRiaWiLPa66wAuHgYphisGjv/W4=; b=IQDJnBsZ9SkVU+gTHSwUxRp9K6uecHKYygVq/MYIwL3PYB6CjA+dkbcAjgKAq2WHWa vp4LkRHW+aFDVHIuwslsfDrGONKkEyskyfRp1gKfg6faXIZieLdckgkifV0OiwhiUWQ7 0hKlqRh57vyhEkFsncSJFx4e2r7PnNd9NBdmi58ljDg4xKTddPN55k3XlWfY9Y4cnpeM zFWOwtAzaQq626FcIePlK0jwK+ys8wAllML7PZcuGA9cvVZupCSWcpDzAKCoaNprpdBS pQvfWz4B725iPTUJooR+kTZgfVvEvGJx4tT0+P93JRDw9x1/+S8YF6ByDnU9sUJILBkP o2rw== X-Gm-Message-State: AOAM533YZwtFaD6n909wEDoHOah2iIerEJsI/8zgGOOvnq1Nr9f1z8eR NNoVAzElzBbRaOgWdTbIpAo= X-Google-Smtp-Source: ABdhPJzuh8texfB50wida4qkUSjtZNbZtqaKEmGtUOsbhrllJR1uFZJsDRLL1rZ9Q0CwjAKLG7U9uQ== X-Received: by 2002:a63:2a96:: with SMTP id q144mr931719pgq.447.1598565678306; Thu, 27 Aug 2020 15:01:18 -0700 (PDT) Received: from ast-mbp.thefacebook.com ([163.114.132.7]) by smtp.gmail.com with ESMTPSA id x28sm3997564pfq.62.2020.08.27.15.01.15 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 27 Aug 2020 15:01:17 -0700 (PDT) From: Alexei Starovoitov To: davem@davemloft.net Cc: daniel@iogearbox.net, josef@toxicpanda.com, bpoirier@suse.com, akpm@linux-foundation.org, hannes@cmpxchg.org, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: [PATCH v3 bpf-next 0/5] bpf: Introduce minimal support for sleepable progs Date: Thu, 27 Aug 2020 15:01:09 -0700 Message-Id: <20200827220114.69225-1-alexei.starovoitov@gmail.com> X-Mailer: git-send-email 2.13.5 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Alexei Starovoitov v2->v3: - switched to minimal allowlist approach. Essentially that means that syscall entry, few btrfs allow_error_inject functions, should_fail_bio(), and two LSM hooks: file_mprotect and bprm_committed_creds are the only hooks that allow attaching of sleepable BPF programs. When comprehensive analysis of LSM hooks will be done this allowlist will be extended. - added patch 1 that fixes prototypes of two mm functions to reliably work with error injection. It's also necessary for resolve_btfids tool to recognize these two funcs, but that's secondary. v1->v2: - split fmod_ret fix into separate patch - added denylist v1: This patch set introduces the minimal viable support for sleepable bpf programs. In this patch only fentry/fexit/fmod_ret and lsm progs can be sleepable. Only array and pre-allocated hash and lru maps allowed. Here is 'perf report' difference of sleepable vs non-sleepable: 3.86% bench [k] __srcu_read_unlock 3.22% bench [k] __srcu_read_lock 0.92% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep 0.50% bench [k] bpf_trampoline_10297 0.26% bench [k] __bpf_prog_exit_sleepable 0.21% bench [k] __bpf_prog_enter_sleepable vs 0.88% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry 0.84% bench [k] bpf_trampoline_10297 0.13% bench [k] __bpf_prog_enter 0.12% bench [k] __bpf_prog_exit vs 0.79% bench [k] bpf_prog_740d4210cdcd99a3_bench_trigger_fentry_sleep 0.72% bench [k] bpf_trampoline_10381 0.31% bench [k] __bpf_prog_exit_sleepable 0.29% bench [k] __bpf_prog_enter_sleepable Sleepable vs non-sleepable program invocation overhead is only marginally higher due to rcu_trace. srcu approach is much slower. Alexei Starovoitov (5): mm/error_inject: Fix allow_error_inject function signatures. bpf: Introduce sleepable BPF programs bpf: Add bpf_copy_from_user() helper. libbpf: support sleepable progs selftests/bpf: Add sleepable tests arch/x86/net/bpf_jit_comp.c | 32 +++++--- include/linux/bpf.h | 4 + include/uapi/linux/bpf.h | 16 ++++ init/Kconfig | 1 + kernel/bpf/arraymap.c | 1 + kernel/bpf/hashtab.c | 12 +-- kernel/bpf/helpers.c | 22 +++++ kernel/bpf/syscall.c | 13 ++- kernel/bpf/trampoline.c | 28 ++++++- kernel/bpf/verifier.c | 81 ++++++++++++++++++- kernel/trace/bpf_trace.c | 2 + mm/filemap.c | 8 +- mm/page_alloc.c | 2 +- tools/include/uapi/linux/bpf.h | 16 ++++ tools/lib/bpf/libbpf.c | 25 +++++- tools/testing/selftests/bpf/bench.c | 2 + .../selftests/bpf/benchs/bench_trigger.c | 17 ++++ .../selftests/bpf/prog_tests/test_lsm.c | 9 +++ tools/testing/selftests/bpf/progs/lsm.c | 66 ++++++++++++++- .../selftests/bpf/progs/trigger_bench.c | 7 ++ 20 files changed, 331 insertions(+), 33 deletions(-)