From patchwork Fri Jan 24 22:30:59 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Charlie Jenkins X-Patchwork-Id: 13949978 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 73DB3C0218C for ; Fri, 24 Jan 2025 22:32:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References:Message-Id :MIME-Version:Subject:Date:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jb7e7+a60GG3tcgpyR1Leiq2fUe+Pu5bw8wD+cUMlNI=; b=t8thatMrs1Ec+D zFsdk8NfjI5Ix+zPIrk6qncdE3oKbSwVCado85QWLWGjoxdA0wKDAfj5yroMptLPMWDGs02iuEuTt nEljvb0y73EkXRbgo/Xnq5O88DvSTsS+eWhnlz/jmrImcSmFojS5rIbT/l7kFEEWAzDhbfbeJS0nT M5GTYdrMnJoXanepfey10AR84V4+3vowWY3G9F8ONJkj/qVbn4BHd+N/wJMBIhk/lQjv4qVxibPqT 0TZNKMdeS+c/dT/s68eQ5WBNmrygw1jD94dIzglrjdVSQONiYuXxyyw2lg1wZ4bPe1+jTlmGjl+/X y8ilKscD6TBimY/4pfhA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tbSDh-0000000Fctx-3AHq; Fri, 24 Jan 2025 22:32:09 +0000 Received: from mail-pl1-x62a.google.com ([2607:f8b0:4864:20::62a]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tbSD2-0000000Fcgc-2cb4 for linux-riscv@lists.infradead.org; Fri, 24 Jan 2025 22:31:29 +0000 Received: by mail-pl1-x62a.google.com with SMTP id d9443c01a7336-2166f1e589cso66689255ad.3 for ; Fri, 24 Jan 2025 14:31:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1737757888; x=1738362688; darn=lists.infradead.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=vNOxwbh8TJLovUJ4xbmkceu/OhoInCtt14EIM5E3MZs=; b=i33xVxIuN4X5v4X6egND/s85bGrty13IFV1z2mLaU4jqFKvm8GgPyvwgOPoFOGl8a4 XdQcW6OQszQAXvWlshQvnAuPdtGgBn2B4pifMiOdW3TmYFEvV5xJ4eQzIV17TNw5ogWs jo/Gpx48bZgSWh6uVKyiTaZZu9pqer8DIj/1b68fnHQfMKQw4wK8yau4oeGGOErwyfuP yOCDlidOhpoIDvCQjl5f3Bn8jWrJ7OU4q81EVZ9PIY389CvSXeHS1hMGmVlLW1qstU6Y UcdQBiWdlfLugyqT/7XQGqXoLgLLY4/3/4rblDcVWLYpw5/aH4kvB2fPcok3I5bVKTzS 06lQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737757888; x=1738362688; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=vNOxwbh8TJLovUJ4xbmkceu/OhoInCtt14EIM5E3MZs=; b=egiXZbu+qQaLBPLl3nxW097j63Tx5YvFsIxuWt/CeHxXeztZl4AGP8uKR4amzeD7j2 hKPUq2SFfVsiizslfvR6yjnMh1qpR/Z/PLPQLQQU55Xgspevr4gG+jOkr8PnpGjTgolb wf2p2uZlx/NcKhPB0EAmt1lmtfvtCQ5DcP7bFM2kNCuwnPH1tzto5LCLgfXVlVWRRPvg ZWqIuxEqsGXt+V7l+INzdnLO7hVMLUm678rdWMOrUiv+hLQcXHLYT1wLDA2HI98qwj4j EoIqSqwxlA7Exiul7/DhF+8qcuxmPvL+EzcQbDxWDOVqifrFM7SdIQy6vnkk3hY/iflR G3CQ== X-Gm-Message-State: AOJu0YzEElV0YlF/bmV90dZzQQZRGqL673qHC4rhLz+guWFlQ9KDGG1J RtA4RWhWmEC30M4PUEx1gw5Vp+fvnzXlLU9Qn97MitotCGk4sdTtzQCu3WSBm/o= X-Gm-Gg: ASbGncsTxaAzZPs6q1l6W6qe0CJvk8aF5SAZ07zfK8A2zNtY/jmHYCh+Dvu1PuOEByn wdrzeam8zCbKmlb+k3gWO1mYzXBeu/CAbNRLSIVXNHoBEdRXNj4KE/xiszN0Lj1RlyyIXT6GjWn 9vFLl1dBqhtVzMMuAhbgoM7wJWDbjTxfp6rFJMdpEZXI2b+HpQ/pzoYdpNDWeGN2CVWhIpA4t9Q chD+wiVEewsTA3eBJKCgdg/ncpacRzOmorwzoZsPooW0fuMeQD8lIlfOfplzfEcaneVh9P+7ikV /675Aij2OSwlktLLeNki X-Google-Smtp-Source: AGHT+IE7NbObNQvQSaPZkmeR+n8U2XghXp9qA7/c1qoqbpDzuOOutMqEPF/BOHkTtclCps2IhnplYw== X-Received: by 2002:a05:6a00:460e:b0:726:54f1:d133 with SMTP id d2e1a72fcca58-72dafa44498mr46196661b3a.12.1737757888123; Fri, 24 Jan 2025 14:31:28 -0800 (PST) Received: from charlie.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-72f8a761150sm2397183b3a.119.2025.01.24.14.31.26 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 24 Jan 2025 14:31:27 -0800 (PST) From: Charlie Jenkins Date: Fri, 24 Jan 2025 14:30:59 -0800 Subject: [PATCH v3 1/4] riscv: entry: Convert ret_from_fork() to C MIME-Version: 1.0 Message-Id: <20250124-riscv_optimize_entry-v3-1-869f36b9e43b@rivosinc.com> References: <20250124-riscv_optimize_entry-v3-0-869f36b9e43b@rivosinc.com> In-Reply-To: <20250124-riscv_optimize_entry-v3-0-869f36b9e43b@rivosinc.com> To: Paul Walmsley , Palmer Dabbelt , Huacai Chen , WANG Xuerui , Thomas Gleixner , Peter Zijlstra , Andy Lutomirski , Alexandre Ghiti Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, loongarch@lists.linux.dev, Charlie Jenkins X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=3493; i=charlie@rivosinc.com; h=from:subject:message-id; bh=e+QmdYfzdsHe2i47iJnp8obSLIn3fW5B1Uv/wF/582w=; b=owGbwMvMwCXWx5hUnlvL8Y3xtFoSQ/oUkT07p5vc3pN3zOnkt2t7t13MSjCoa19Xuf7PhTMrZ mmaPX4S01HKwiDGxSArpsjCc62BufWOftlR0bIJMHNYmUCGMHBxCsBEPFYx/A8WTt5ryjLVpMH1 TErO2sWKx6RENDf46fAGP0z2XfrJ+A0jww+e91PXpHawiKp7p8QaGc1fP/81y37mGUU9B1q3fG/ 5zgYA X-Developer-Key: i=charlie@rivosinc.com; a=openpgp; fpr=7D834FF11B1D8387E61C776FFB10D1F27D6B1354 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250124_143128_667663_81453070 X-CRM114-Status: GOOD ( 11.88 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org Move the main section of ret_from_fork() to C to allow inlining of syscall_exit_to_user_mode(). Signed-off-by: Charlie Jenkins Reviewed-by: Alexandre Ghiti --- arch/riscv/include/asm/asm-prototypes.h | 1 + arch/riscv/kernel/entry.S | 15 ++++++--------- arch/riscv/kernel/process.c | 14 ++++++++++++-- 3 files changed, 19 insertions(+), 11 deletions(-) diff --git a/arch/riscv/include/asm/asm-prototypes.h b/arch/riscv/include/asm/asm-prototypes.h index cd627ec289f163a630b73dd03dd52a6b28692997..733ff609778797001006c33bba9e3cc5b1f15387 100644 --- a/arch/riscv/include/asm/asm-prototypes.h +++ b/arch/riscv/include/asm/asm-prototypes.h @@ -52,6 +52,7 @@ DECLARE_DO_ERROR_INFO(do_trap_ecall_s); DECLARE_DO_ERROR_INFO(do_trap_ecall_m); DECLARE_DO_ERROR_INFO(do_trap_break); +asmlinkage void ret_from_fork(void *fn_arg, int (*fn)(void *), struct pt_regs *regs); asmlinkage void handle_bad_stack(struct pt_regs *regs); asmlinkage void do_page_fault(struct pt_regs *regs); asmlinkage void do_irq(struct pt_regs *regs); diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 33a5a9f2a0d4e1eeccfb3621b9e518b88e1b0704..b2dc5e7c7b3a843fa4aa02eba2a911eb3ce31d1f 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -319,17 +319,14 @@ SYM_CODE_END(handle_kernel_stack_overflow) ASM_NOKPROBE(handle_kernel_stack_overflow) #endif -SYM_CODE_START(ret_from_fork) +SYM_CODE_START(ret_from_fork_asm) call schedule_tail - beqz s0, 1f /* not from kernel thread */ - /* Call fn(arg) */ - move a0, s1 - jalr s0 -1: - move a0, sp /* pt_regs */ - call syscall_exit_to_user_mode + move a0, s1 /* fn_arg */ + move a1, s0 /* fn */ + move a2, sp /* pt_regs */ + call ret_from_fork j ret_from_exception -SYM_CODE_END(ret_from_fork) +SYM_CODE_END(ret_from_fork_asm) #ifdef CONFIG_IRQ_STACKS /* diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 58b6482c2bf662bf5224ca50c8e21a68760a6b41..0d07e6d8f6b57beba438dbba5e8c74a014582bee 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -17,7 +17,9 @@ #include #include #include +#include +#include #include #include #include @@ -36,7 +38,7 @@ unsigned long __stack_chk_guard __read_mostly; EXPORT_SYMBOL(__stack_chk_guard); #endif -extern asmlinkage void ret_from_fork(void); +extern asmlinkage void ret_from_fork_asm(void); void noinstr arch_cpu_idle(void) { @@ -206,6 +208,14 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) return 0; } +asmlinkage void ret_from_fork(void *fn_arg, int (*fn)(void *), struct pt_regs *regs) +{ + if (unlikely(fn)) + fn(fn_arg); + + syscall_exit_to_user_mode(regs); +} + int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) { unsigned long clone_flags = args->flags; @@ -242,7 +252,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) p->thread.riscv_v_flags = 0; if (has_vector()) riscv_v_thread_alloc(p); - p->thread.ra = (unsigned long)ret_from_fork; + p->thread.ra = (unsigned long)ret_from_fork_asm; p->thread.sp = (unsigned long)childregs; /* kernel sp */ return 0; }