From patchwork Thu May 11 09:32:33 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Song Shuai X-Patchwork-Id: 13237723 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 52217C7EE24 for ; Thu, 11 May 2023 09:33:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237513AbjEKJdS (ORCPT ); Thu, 11 May 2023 05:33:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53766 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237691AbjEKJc7 (ORCPT ); Thu, 11 May 2023 05:32:59 -0400 Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 97A0C83D4; Thu, 11 May 2023 02:32:54 -0700 (PDT) Received: by mail-pf1-x42b.google.com with SMTP id d2e1a72fcca58-64388cf3263so5948492b3a.3; Thu, 11 May 2023 02:32:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1683797574; x=1686389574; 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=tNfO2sYqLGwvbXj7b+RBDP96xK5wbSnAMcdu5du1sJ8=; b=eoMulosYXlZJab5DJ69Z7eSwNjOXQGja17mHz30M633x9kOzrdRevDa7ABGzmw7SDZ WJ7Dn+AnRqSj4SDHUmxIey0NyfZ2maR18lo93vDroKlJTTNy/NVP+6DVApP0URcFiLeM hW9yllx9OXV9nUBrCVl8purextKsoxykUtXedYHSE50X1LrYe/85Zvwj9MT2BLFkWzhG pN9wzYBuSe70XKzqkzDcMM0VcE9LEjwVJwha4px900CbJ2hQXXgCUZgK00MYiF1KxUp0 mqpzj+Ys5QXW8oFfW9Z3kVo+NZoAJ3lMfQkKC74MfTXJFZ4aBgDuLq2Acp2ODRqYfaXS zasQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1683797574; x=1686389574; 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=tNfO2sYqLGwvbXj7b+RBDP96xK5wbSnAMcdu5du1sJ8=; b=HzGzv+5WJveOGcc2YF+g1JCq2FUj5cY0yIHFKGdfVTHcpIM2XnyeZoRR6yDJRqOk4i cO4oLncB9QdQqR5Ec8fpFZsNcvEYUAq9pATf8HTqJPQUZ0wxiIWpjH8WOK23IcrtM5U/ 91AZjMPl0xQ4a0OY8ZNXSoehBjNeJKFyh7ARAJFTYatQh/j5JofTuLB13HAcd2zta4Mu fiYCrnZFrZ5PJ28ZR4Z1/DYnyPEb/6a4hBwessup64vZ16ePYem2M1iZGCgFOfROD4FD ClFF+JsKnUUxRcO8EsBkkTX3Dy54x5YpPMgN+/Dh6s/k8A8jtINCOUol4D47KGjy3IWq /L6Q== X-Gm-Message-State: AC+VfDyEwe3CGsKKE82E7eQiNjT4/98t74zAcTVVW1bkFaZxH+vuOHPj SLhx3qhRfic5yXndqh4NHHs= X-Google-Smtp-Source: ACHHUZ5tqFUzRUER4uYbdBP0mJZhbBdjxE25Tip8/gF5MrL7qlT/u9FSLspRUNnm8mXPQ+UM4wzM5g== X-Received: by 2002:a05:6a20:8e07:b0:101:8f00:595f with SMTP id y7-20020a056a208e0700b001018f00595fmr8918036pzj.44.1683797573963; Thu, 11 May 2023 02:32:53 -0700 (PDT) Received: from localhost.localdomain ([221.226.144.218]) by smtp.gmail.com with ESMTPSA id v16-20020aa78510000000b00627e87f51a5sm4875400pfn.161.2023.05.11.02.32.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 May 2023 02:32:53 -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 3/4] riscv: ftrace: Add DYNAMIC_FTRACE_WITH_DIRECT_CALLS support Date: Thu, 11 May 2023 17:32:33 +0800 Message-Id: <20230511093234.3123181-4-suagrfillet@gmail.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20230511093234.3123181-1-suagrfillet@gmail.com> References: <20230511093234.3123181-1-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 Acked-by: Björn Töpel --- 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 fb8286b80cfc..b6f4e1847d61 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) + mv 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 */