From patchwork Wed May 10 10:18:56 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Song Shuai X-Patchwork-Id: 13236722 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 B3F2CC7EE23 for ; Wed, 10 May 2023 10:19:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236534AbjEJKTh (ORCPT ); Wed, 10 May 2023 06:19:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39838 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236566AbjEJKTb (ORCPT ); Wed, 10 May 2023 06:19:31 -0400 Received: from mail-pg1-x529.google.com (mail-pg1-x529.google.com [IPv6:2607:f8b0:4864:20::529]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E3C2176B8; Wed, 10 May 2023 03:19:29 -0700 (PDT) Received: by mail-pg1-x529.google.com with SMTP id 41be03b00d2f7-52c30fa5271so3617647a12.0; Wed, 10 May 2023 03:19:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683713969; x=1686305969; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=S5vFEEjmnopDHc0xjFlK98v5d+a6ehUkb1OxTzirFXs=; b=MycZHAKqtatZ4GlFbUi6sg2PZR12Yb/VQzOokoxdbGJHe+MlTAHBhFPtZ5BKPygoBK B2MeyhOrY0UaP/fmkmLdjUOaHYR6A1E/TdGzjOaXlYa0H2ewEKI2FavlI9UYveb9lbb3 SJJNR5WOBTnan1uhg8+i/AidIcRCJ6WKOryfBJEmkUNiX0Yd70C827SLJFmVRCxlRFUi DKCGIkPzqO5LDRRV9kBNFpQWKxYWqMWV3ZVEV1D6ygubMSAWe1GBwksgIkU2yw038UKb YCuYCnFd2GxkCM4Egf38kWeZV3K/GO7MCzXIRDTa7c0m5ZRgxISdHfOqrN0odure0JmN h0Tw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683713969; x=1686305969; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=S5vFEEjmnopDHc0xjFlK98v5d+a6ehUkb1OxTzirFXs=; b=ZQPql6dB+jVSydxAL0PJEUmeTSFqiYUKdUaEtOw0bcQLuSrRgMt+KhXR42+Rp6H/0Z v9Fjv36cSkFXHec8yUWjRiUhKbruQtP8eqKerMkOpeLCU4vFwsJxlFXGgLAY47nCkeb3 omZAmJ0SejDNGkjlgG31PNG8kfYFMusnL2G/iS8ZwYYoYbh++/gxZaya1O1cKi6mnjha 6O/QfTinz2Q6U/RYX7ErZVplbAvIAPbAkr7Qc8Mzs2hAdcTdhfge27EPpLlMhToVte4T W1aaauSzUCjbnbjeB+6R/D97oFdsjL+FOmE+/QlswQSYr0ZssHMtGmzcF3GDe4AVJI57 JjGg== X-Gm-Message-State: AC+VfDzu+WlHVWUYQmRbLK9UtaBOnCgoyNzOlvElcDENNbuFwhDmAhPL FCo+mMMvM0NkKZPT+AEe1ZI= X-Google-Smtp-Source: ACHHUZ7aCsulcH4KBH9sfNqATruLNWf325mTetT0mL5FTQwIuCSfyScEkxyogQ3R0zacyTIYXRqmxw== X-Received: by 2002:a17:902:cece:b0:1a8:626:6d9d with SMTP id d14-20020a170902cece00b001a806266d9dmr22665000plg.62.1683713969110; Wed, 10 May 2023 03:19:29 -0700 (PDT) Received: from localhost.localdomain ([221.226.144.218]) by smtp.gmail.com with ESMTPSA id p16-20020a170902e75000b001aadd0d7364sm3393419plf.83.2023.05.10.03.19.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 10 May 2023 03:19:28 -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 Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [PATCH V9 3/4] riscv: ftrace: Add DYNAMIC_FTRACE_WITH_DIRECT_CALLS support Date: Wed, 10 May 2023 18:18:56 +0800 Message-Id: <20230510101857.2953955-4-suagrfillet@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230510101857.2953955-1-suagrfillet@gmail.com> References: <20230510101857.2953955-1-suagrfillet@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-trace-kernel@vger.kernel.org This patch adds DYNAMIC_FTRACE_WITH_DIRECT_CALLS support for RISC-V. select the DYNAMIC_FTRACE_WITH_DIRECT_CALLS to provide the register_ftrace_direct[_multi] interfaces allowing users 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 modifying direct_caller. To make the direct_caller and the other ftrace hooks (eg. function/fgraph tracer, k[ret]probes) co-exist, a temporary register is 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. Signed-off-by: Song Shuai Tested-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/Kconfig | 1 + arch/riscv/include/asm/ftrace.h | 8 ++++++++ arch/riscv/kernel/mcount-dyn.S | 10 ++++++++++ 3 files changed, 19 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index e0632493482f..fdf0b219a02c 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -144,6 +144,7 @@ config RISCV select UACCESS_MEMCPY if !MMU select ZONE_DMA32 if 64BIT select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && MMU && (CLANG_SUPPORTS_DYNAMIC_FTRACE || GCC_SUPPORTS_DYNAMIC_FTRACE) + select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL select HAVE_FUNCTION_GRAPH_TRACER diff --git a/arch/riscv/include/asm/ftrace.h b/arch/riscv/include/asm/ftrace.h index 84f856a3286e..84904c1e4369 100644 --- a/arch/riscv/include/asm/ftrace.h +++ b/arch/riscv/include/asm/ftrace.h @@ -114,6 +114,14 @@ struct ftrace_regs; void ftrace_graph_func(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct ftrace_regs *fregs); #define ftrace_graph_func ftrace_graph_func + +static inline void +__arch_ftrace_set_direct_caller(struct pt_regs *regs, unsigned long addr) +{ + regs->t1 = addr; +} +#define arch_ftrace_set_direct_caller(fregs, addr) \ + __arch_ftrace_set_direct_caller(&(fregs)->regs, addr) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ #endif /* __ASSEMBLY__ */ diff --git a/arch/riscv/kernel/mcount-dyn.S b/arch/riscv/kernel/mcount-dyn.S index f26e9f6e2fed..9d405baedb52 100644 --- a/arch/riscv/kernel/mcount-dyn.S +++ b/arch/riscv/kernel/mcount-dyn.S @@ -231,6 +231,7 @@ ENDPROC(ftrace_caller) #else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ ENTRY(ftrace_regs_caller) + move t1, zero SAVE_ABI_REGS 1 PREPARE_ARGS @@ -239,7 +240,10 @@ ftrace_regs_call: call ftrace_stub RESTORE_ABI_REGS 1 + bnez t1,.Ldirect jr t0 +.Ldirect: + jr t1 ENDPROC(ftrace_regs_caller) ENTRY(ftrace_caller) @@ -254,3 +258,9 @@ ftrace_call: jr t0 ENDPROC(ftrace_caller) #endif /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */ + +#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS +SYM_CODE_START(ftrace_stub_direct_tramp) + jr t0 +SYM_CODE_END(ftrace_stub_direct_tramp) +#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */