From patchwork Thu Mar 16 17:38:04 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florent Revest X-Patchwork-Id: 13178142 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 A558DC6FD19 for ; Thu, 16 Mar 2023 17:38:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229814AbjCPRik (ORCPT ); Thu, 16 Mar 2023 13:38:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229584AbjCPRij (ORCPT ); Thu, 16 Mar 2023 13:38:39 -0400 Received: from mail-wm1-x335.google.com (mail-wm1-x335.google.com [IPv6:2a00:1450:4864:20::335]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7652A1B2F0 for ; Thu, 16 Mar 2023 10:38:37 -0700 (PDT) Received: by mail-wm1-x335.google.com with SMTP id p16so1808825wmq.5 for ; Thu, 16 Mar 2023 10:38:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1678988316; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=U5mSMxwdN0IR5nAI9XvdYIXU9bwtI93jGwawWBVdvG8=; b=Dxs14Bj7A6T+cKbTpK2Sr5K3V6GlyRbuHWlE4K0dGbM4pDIOSwjsb5VM2+iga4ht4M sY7R67sqg3IZml4TtJi1d0ePthVPWeyBgXjC4aBut8+2fLjigEV5rL9+Y0pQY6qv0j9r NZLjtRF7GEYx63rOSN253WcUx8r4tJ1hQn5fM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1678988316; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=U5mSMxwdN0IR5nAI9XvdYIXU9bwtI93jGwawWBVdvG8=; b=Ae3BfMEqcNUqxRBedLvglPjklxYOjfR10TGRepKq1KLg502Bwlt0wDeaAQzCp723cv jDmsTPKGNxiLxBol7GjUsrztvrxtBk8GJopZM6zWk3Q/OUIsdBM7ByjouxePhy7gucLo i4Oi1YoE2SZoUqNJLxvs6cQSY1ovIdnhpBvJ6BEN87qeuKnkEwsZoekw0FSeXB8Vzwl/ S6f0VI0z4pOtQ3AT45o2rh9ShBd6uHdS91dObaxt4lN1N+y5buvOaeNibfu+EuEdyQdH IbIenXVXMsyGiLreJAMdhm5ngu6ERWPDn8FVtFH9zVHyiQZKhSZS5IazTIiZHRVO8y4N oUrg== X-Gm-Message-State: AO0yUKU3jOfFp3kg5FmUsZYEQ9awHgg/rOVRrV1lN53uXHAh1zusCDXi J8CCaFGUo13P+PbN/UjLiwAirA== X-Google-Smtp-Source: AK7set+SPBlj7qjk2ovvOr0jigoTcKalAVDYTuxbkxBRwGrIsClH1KoAnTY10DcSl+pLzdrq3q2kXQ== X-Received: by 2002:a05:600c:4f91:b0:3ed:2c92:9f4f with SMTP id n17-20020a05600c4f9100b003ed2c929f4fmr9602119wmq.10.1678988315837; Thu, 16 Mar 2023 10:38:35 -0700 (PDT) Received: from revest.zrh.corp.google.com ([2a00:79e0:9d:6:24ff:9ff7:736e:20a6]) by smtp.gmail.com with ESMTPSA id t14-20020a1c770e000000b003daf7721bb3sm5596436wmi.12.2023.03.16.10.38.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 16 Mar 2023 10:38:35 -0700 (PDT) From: Florent Revest To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: rostedt@goodmis.org, mhiramat@kernel.org, mark.rutland@arm.com, ast@kernel.org, daniel@iogearbox.net, kpsingh@kernel.org, revest@chromium.org, jolsa@kernel.org Subject: [PATCH 0/7] Refactor ftrace direct call APIs Date: Thu, 16 Mar 2023 18:38:04 +0100 Message-Id: <20230316173811.1223508-1-revest@chromium.org> X-Mailer: git-send-email 2.40.0.rc2.332.ga46443480c-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org This series refactors ftrace direct call APIs in preparation for arm64 support. It is roughly a subset of [1] rebased on v6.3-rc2 and meant to be taken by Steven's tree before all the arm64 specific bits. The first patch was suggested by Steven in a review of [1], it makes it more obvious to the caller that filters probably need to be freed when unregistering a direct call. The next three patches consolidate the two existing ftrace APIs for registering direct calls. They are only split to make the reviewer's life easier. Currently, there is both a _ftrace_direct and _ftrace_direct_multi API. Apart from samples and selftests, there are no users of the _ftrace_direct API left in-tree so this deletes it and renames the _ftrace_direct_multi API to _ftrace_direct for simplicity. The main benefit of this refactoring is that, with the API that's left, an ftrace_ops backing a direct call will only ever point to one direct call. We can therefore store the direct called trampoline address in the ops (patch 5) and, in the future arm64 series, look it up from the ftrace trampoline. (in the meantime, it makes call_direct_funcs a bit simpler too) Ftrace direct calls technically don't need DYNAMIC_FTRACE_WITH_REGS so this extends its support to DYNAMIC_FTRACE_WITH_ARGS (patch 6). arm64 won't support DYNAMIC_FTRACE_WITH_REGS. Finally, it fixes the ABI of the stub direct call trampoline used in ftrace selftests. This has been tested on x86_64 with: 1- CONFIG_FTRACE_SELFTEST 2- samples/ftrace/*.ko 1: https://lore.kernel.org/all/20230207182135.2671106-1-revest@chromium.org/T/#t Florent Revest (6): ftrace: Let unregister_ftrace_direct_multi() call ftrace_free_filter() ftrace: Replace uses of _ftrace_direct APIs with _ftrace_direct_multi ftrace: Remove the legacy _ftrace_direct API ftrace: Rename _ftrace_direct_multi APIs to _ftrace_direct APIs ftrace: Store direct called addresses in their ops ftrace: Make DIRECT_CALLS work WITH_ARGS and !WITH_REGS Mark Rutland (1): ftrace: selftest: remove broken trace_direct_tramp arch/s390/kernel/mcount.S | 5 + arch/x86/kernel/ftrace_32.S | 5 + arch/x86/kernel/ftrace_64.S | 4 + include/linux/ftrace.h | 61 +-- kernel/bpf/trampoline.c | 12 +- kernel/trace/Kconfig | 2 +- kernel/trace/ftrace.c | 438 ++------------------ kernel/trace/trace_selftest.c | 19 +- samples/Kconfig | 2 +- samples/ftrace/ftrace-direct-modify.c | 10 +- samples/ftrace/ftrace-direct-multi-modify.c | 9 +- samples/ftrace/ftrace-direct-multi.c | 5 +- samples/ftrace/ftrace-direct-too.c | 10 +- samples/ftrace/ftrace-direct.c | 10 +- 14 files changed, 101 insertions(+), 491 deletions(-)