From patchwork Wed Aug 23 15:15:28 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Masami Hiramatsu (Google)" X-Patchwork-Id: 13362746 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 2CA85EE4993 for ; Wed, 23 Aug 2023 15:17:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235863AbjHWPRi (ORCPT ); Wed, 23 Aug 2023 11:17:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48862 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236967AbjHWPRg (ORCPT ); Wed, 23 Aug 2023 11:17:36 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51CAD10D9; Wed, 23 Aug 2023 08:17:10 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4733E61B2F; Wed, 23 Aug 2023 15:15:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBCA5C433C7; Wed, 23 Aug 2023 15:15:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1692803734; bh=ASbMdCajbcDHLaUjdYxqw9oJ/MlOFQjowbpMQ9Bc3tQ=; h=From:To:Cc:Subject:Date:From; b=J/RefnlCaBda4PdVcYjWR3IbDkE0mG0vxMvz2hnYhaO5ClKwcm8lxO8AxJ9QLMb6M rtJob9vFs8qgToO6kK5Il5NEih4ib2W7YWYUin/fXvjMP6HA1j506H7RaDep9iBJe9 ns7w6p2NE9KVLQ/SjxN5Fo4kbp0OubH5AX2S9lPI9mF5rniZWQvjMunjnZWgdIYgWP +Ubu8PvJvB+kL2TCM1MUl8N2womMJJpFI8Q/lsmDEKaYAu/CcIaZWuqTmGrQ16wAf5 JqYe/pEWty1UTjOl5LcooD8WSdvS7+tjGwGbmwOpJo7j3E6yYbkSW5CqkRV+vvO9xZ 1UMN8/6fuWVZA== From: "Masami Hiramatsu (Google)" To: Alexei Starovoitov , Steven Rostedt , Florent Revest Cc: linux-trace-kernel@vger.kernel.org, LKML , Martin KaFai Lau , bpf , Sven Schnelle , Alexei Starovoitov , Jiri Olsa , Arnaldo Carvalho de Melo , Daniel Borkmann , Alan Maguire , Mark Rutland , Peter Zijlstra , Thomas Gleixner Subject: [PATCH v4 0/9] bpf: fprobe: rethook: Use ftrace_regs instead of pt_regs Date: Thu, 24 Aug 2023 00:15:28 +0900 Message-Id: <169280372795.282662.9784422934484459769.stgit@devnote2> X-Mailer: git-send-email 2.34.1 User-Agent: StGit/0.19 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org Hi, Here is the 4th version of the series to use ftrace_regs instead of pt_regs in fprobe. The previous version is here; https://lore.kernel.org/all/169181859570.505132.10136520092011157898.stgit@devnote2/ This version fixes the issues pointed in the previous series; fix document description, keep CONFIG_FPROBE dependency for multi-kprobe, add static_assert check for ftrace_regs size, reorder the ftrace_partial_regs() patch for perf fprobe event support, introduce per-cpu pt_regs stack for perf fprobe event and add Florent's Ack (Thanks!). Also this adds a new documentation patch to clarify that the $argN and $retval is best effort. - Document fix for the current fprobe callback prototype - Simply replace pt_regs in fprobe_entry_handler with ftrace_regs. - Expose ftrace_regs even if CONFIG_FUNCTION_TRACER=n. - Introduce ftrace_partial_regs(). (This changes ARM64 which needs a custom implementation) - Replace pt_regs in rethook and fprobe_exit_handler with ftrace_regs. This introduce a new HAVE_PT_REGS_TO_FTRACE_REGS_CAST which means ftrace_regs is just a wrapper of pt_regs (except for arm64, other architectures do this) - Update fprobe-events to use ftrace_regs natively. - Update bpf multi-kprobe handler use ftrace_partial_regs(). - Update document for new fprobe callbacks. - Add notes for the $argN and $retval. This series can be applied against the probes/core branch on linux-trace tree. This series can also be found below branch. https://git.kernel.org/pub/scm/linux/kernel/git/mhiramat/linux.git/log/?h=topic/fprobe-ftrace-regs Thank you, --- Masami Hiramatsu (Google) (9): Documentation: probes: Add a new ret_ip callback parameter fprobe: Use fprobe_regs in fprobe entry handler tracing: Expose ftrace_regs regardless of CONFIG_FUNCTION_TRACER fprobe: rethook: Use ftrace_regs in fprobe exit handler and rethook ftrace: Add ftrace_partial_regs() for converting ftrace_regs to pt_regs tracing/fprobe: Enable fprobe events with CONFIG_DYNAMIC_FTRACE_WITH_ARGS bpf: Enable kprobe_multi feature if CONFIG_FPROBE is enabled Documentations: probes: Update fprobe document to use ftrace_regs Documentation: tracing: Add a note about argument and retval access Documentation/trace/fprobe.rst | 18 +++-- Documentation/trace/fprobetrace.rst | 8 ++ Documentation/trace/kprobetrace.rst | 8 ++ arch/Kconfig | 1 arch/arm64/include/asm/ftrace.h | 11 +++ arch/loongarch/Kconfig | 1 arch/s390/Kconfig | 1 arch/s390/include/asm/ftrace.h | 4 + arch/x86/Kconfig | 1 arch/x86/kernel/rethook.c | 13 ++- include/linux/fprobe.h | 4 + include/linux/ftrace.h | 89 ++++++++++++++++++------ include/linux/rethook.h | 11 ++- kernel/kprobes.c | 10 ++- kernel/trace/Kconfig | 9 ++ kernel/trace/bpf_trace.c | 14 ++-- kernel/trace/fprobe.c | 10 +-- kernel/trace/rethook.c | 16 ++-- kernel/trace/trace_fprobe.c | 131 ++++++++++++++++++++++++++--------- kernel/trace/trace_probe_tmpl.h | 2 - lib/test_fprobe.c | 10 +-- samples/fprobe/fprobe_example.c | 4 + 22 files changed, 267 insertions(+), 109 deletions(-) -- Masami Hiramatsu (Google)