From patchwork Thu May 11 09:32:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Song Shuai X-Patchwork-Id: 13237720 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 D6E28C7EE24 for ; Thu, 11 May 2023 09:32:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237579AbjEKJcv (ORCPT ); Thu, 11 May 2023 05:32:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237560AbjEKJcp (ORCPT ); Thu, 11 May 2023 05:32:45 -0400 Received: from mail-pf1-x432.google.com (mail-pf1-x432.google.com [IPv6:2607:f8b0:4864:20::432]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5974A9EF3; Thu, 11 May 2023 02:32:44 -0700 (PDT) Received: by mail-pf1-x432.google.com with SMTP id d2e1a72fcca58-643846c006fso8889814b3a.0; Thu, 11 May 2023 02:32:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683797564; x=1686389564; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=6vXnMURHEJ8PAq/yF+MqschLuaBTTxiauhRnntfE9HU=; b=XsF+kvP7FH3fy3Wnl2+NuuJ22RKhSaKhWque41ruq7UcHrgEKYwwKB6V6MpWEz0CY/ gRQzKllmXqpG+zQEGohBhhrQsyFZVzWxIVlHCgaE8E/60qAlodVIGpASrJ742FAAbQZy AHWnHQYihyvynxSewwrGL7b3zmtG3SDH6a3hV3vBybioRbUww8HImWeFRkOyzhRMJwLz 8/BS08MA4AMiiyVbMqRH/GPelSVDQJQ2ltI8DT6dQAvvpdqRVfNaP8TBr+gd2KxiMCCf CJ+ias5XljlmVPQxtTA7PW+g2ZAp1yFTr08RcixyL2EsTUbyDFhr9e7OD/PN5QohNV9U oLfw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683797564; x=1686389564; 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=6vXnMURHEJ8PAq/yF+MqschLuaBTTxiauhRnntfE9HU=; b=eq6ph6vJik/tNgkFp2IrcbZHrzjaJ7SKEUv3kJHv6VAHOWIvlvtFgd9KzxL8iAhJvm iLO0rWVUf2ibSklVE0EojFYvXY1vkp8eRadtPWOZghfa/+zlb+VERTw1z+vSJxu2oTjq eE+SNVoWUdYfW/qOkHrL7PTLcQVHysZvwzocDrNNtQu2Dk0mtuwFJRTi46dBjFOaSIe4 EiorODmeI0BM8IhbWm9w6GRvimHFCgyfjnqnQI91TKgqTYZmMK5KqZsLZjxQ8lIhMNom kNzXif8bmziHGocyl8wgmC0fiePbx+2+2RrEHGt9YjO3J8oo7l6uaUP0dq8mX9UFuDOd oz9g== X-Gm-Message-State: AC+VfDyZheA/odIIaew+QP3s/XJMy/LGTIgiWuMzKrzpFy+NEcx6bQhr PaxxZqyTUVC5rqD0BxJPXVI= X-Google-Smtp-Source: ACHHUZ7XOztf4r9M4LeORS3FUN/4uqoeVPPvSkfvXK+e2PGtjpfcE0wMaxX+pLUUI1zbbJdnz1A9eQ== X-Received: by 2002:a05:6a00:2189:b0:63d:4446:18ab with SMTP id h9-20020a056a00218900b0063d444618abmr25889461pfi.23.1683797563678; Thu, 11 May 2023 02:32:43 -0700 (PDT) Received: from localhost.localdomain ([221.226.144.218]) by smtp.gmail.com with ESMTPSA id v16-20020aa78510000000b00627e87f51a5sm4875400pfn.161.2023.05.11.02.32.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 May 2023 02:32:43 -0700 (PDT) From: Song Shuai To: paul.walmsley@sifive.com, palmer@dabbelt.com, aou@eecs.berkeley.edu, rostedt@goodmis.org, mhiramat@kernel.org, mark.rutland@arm.com, guoren@kernel.org, suagrfillet@gmail.com, jszhang@kernel.org, e.shatokhin@yadro.com, bjorn@rivosinc.com Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH V10 0/4] riscv: Optimize function trace Date: Thu, 11 May 2023 17:32:30 +0800 Message-Id: <20230511093234.3123181-1-suagrfillet@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org Changes in v10: - add Acked-by from Björn Töpel in patch 2 and patch 4 - replace `move` with `mv` in patch3 - prettify patch 2/4 with proper tabs You can directly try it with: https://github.com/sugarfillet/linux/tree/6.4-rc1-rv-ftrace-v10 This series optimizes function trace. The first 3 independent patches has been picked in the V7 version of this series, the subsequent version continues the following 4 patches: select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY [1] (patch 1) ========================================================== In RISC-V, -fpatchable-function-entry option is used to support dynamic ftrace in this commit afc76b8b8011 ("riscv: Using PATCHABLE_FUNCTION_ENTRY instead of MCOUNT"). So recordmcount don't have to be called to create the __mcount_loc section before the vmlinux linking. Here selects FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY to tell Makefile not to run recordmcount. Make function graph use ftrace directly [2] (patch 2) ======================================================== In RISC-V architecture, when we enable the ftrace_graph tracer on some functions, the function tracings on other functions will suffer extra graph tracing work. In essence, graph_ops isn't limited by its func_hash due to the global ftrace_graph_[regs]_call label. That should be corrected. What inspires me is the commit 0c0593b45c9b ("x86/ftrace: Make function graph use ftrace directly") that uses graph_ops::func function to install return_hooker and makes the function called against its func_hash. Add WITH_DIRECT_CALLS support [3] (patch 3, 4) ============================================== This series adds DYNAMIC_FTRACE_WITH_DIRECT_CALLS support for RISC-V. SAMPLE_FTRACE_DIRECT and SAMPLE_FTRACE_DIRECT_MULTI are also included here as the samples for testing DIRECT_CALLS related interface. First, select the DYNAMIC_FTRACE_WITH_DIRECT_CALLS to provide register_ftrace_direct[_multi] interfaces allowing user to register the customed trampoline (direct_caller) as the mcount for one or more target functions. And modify_ftrace_direct[_multi] are also provided for modify direct_caller. At the same time, the samples in ./samples/ftrace/ can be built as kerenl module for testing these interfaces with SAMPLE_FTRACE_DIRECT and SAMPLE_FTRACE_DIRECT_MULTI selected. Second, to make the direct_caller and the other ftrace hooks (eg. function/fgraph tracer, k[ret]probes) co-exist, a temporary register are nominated to store the address of direct_caller in ftrace_regs_caller. After the setting of the address direct_caller by direct_ops->func and the RESTORE_REGS in ftrace_regs_caller, direct_caller will be jumped to by the `jr` inst. The series's old changes related these patches ========================================== Changes in v9: https://lore.kernel.org/linux-riscv/20230510101857.2953955-1-suagrfillet@gmail.com/ 1. add Acked-by from Björn Töpel in patch 1 2. rebase patch2/patch3 on Linux v6.4-rc1 - patch 2: to make the `SAVE_ABI_REGS` configurable, revert the modification of mcount-dyn.S from commit (45b32b946a97 "riscv: entry: Consolidate general regs saving/restoring") - patch 3: to pass the trace_selftest, add the implement of `ftrace_stub_direct_tramp` from commit (fee86a4ed536 "ftrace: selftest: remove broken trace_direct_tramp") ; and fixup the context conflict in Kconfig Changes in v8: https://lore.kernel.org/linux-riscv/20230324033342.3177979-1-suagrfillet@gmail.com/ - Fix incorrect address values in the 4nd patch - Rebased on v6.3-rc2 Changes in v7: https://lore.kernel.org/linux-riscv/20230112090603.1295340-1-guoren@kernel.org/ - Fixup RESTORE_ABI_REGS by remove PT_T0(sp) overwrite. - Add FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY [1] - Fixup kconfig with HAVE_SAMPLE_FTRACE_DIRECT & HAVE_SAMPLE_FTRACE_DIRECT_MULTI Changes in v6: https://lore.kernel.org/linux-riscv/20230107133549.4192639-1-guoren@kernel.org/ - Replace 8 with MCOUNT_INSN_SIZE - Replace "REG_L a1, PT_RA(sp)" with "mv a1, ra" - Add Evgenii Shatokhin comment Changes in v5: https://lore.kernel.org/linux-riscv/20221208091244.203407-1-guoren@kernel.org/ - Sort Kconfig entries in alphabetical order. Changes in v4: https://lore.kernel.org/linux-riscv/20221129033230.255947-1-guoren@kernel.org/ - Include [3] for maintenance. [Song Shuai] Changes in V3: https://lore.kernel.org/linux-riscv/20221123153950.2911981-1-guoren@kernel.org/ - Include [2] for maintenance. [Song Shuai] [1]: https://lore.kernel.org/linux-riscv/CAAYs2=j3Eak9vU6xbAw0zPuoh00rh8v5C2U3fePkokZFibWs2g@mail.gmail.com/T/#t [2]: https://lore.kernel.org/lkml/20221120084230.910152-1-suagrfillet@gmail.com/ [3]: https://lore.kernel.org/linux-riscv/20221123142025.1504030-1-suagrfillet@gmail.com/ Song Shuai (4): riscv: select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY riscv: ftrace: Add ftrace_graph_func riscv: ftrace: Add DYNAMIC_FTRACE_WITH_DIRECT_CALLS support samples: ftrace: Add riscv support for SAMPLE_FTRACE_DIRECT[_MULTI] arch/riscv/Kconfig | 4 + arch/riscv/include/asm/ftrace.h | 19 +- arch/riscv/kernel/ftrace.c | 30 ++- arch/riscv/kernel/mcount-dyn.S | 200 ++++++++++++++++---- samples/ftrace/ftrace-direct-modify.c | 34 ++++ samples/ftrace/ftrace-direct-multi-modify.c | 40 ++++ samples/ftrace/ftrace-direct-multi.c | 24 +++ samples/ftrace/ftrace-direct-too.c | 27 +++ samples/ftrace/ftrace-direct.c | 23 +++ 9 files changed, 345 insertions(+), 56 deletions(-)