From patchwork Wed Jan 22 22:56:20 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Charlie Jenkins X-Patchwork-Id: 13947688 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 7834FC02181 for ; Wed, 22 Jan 2025 22:57:04 +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=/YrUj+u1tbMFoOiYKvOcK/ydWhS0sgaQajVURmuXwsI=; b=IGfHt2MXJ68Ezx CT8gGdl7R6qPDKGngxnK5vKq9D9HNxLe9VdpWzQyeDyI6yTiXf0Hv5LIG7swVIqlCLW4K4dON6lZM k1lbJGJOPiI0dg3XMqEnxh+7HOA4L184lPwqP3e4WhjQ2yEcwfF1XKty/uQGyjNd/WZ5yHOC7w4v2 WqquiNTTEjDUlrH+0OQMzmFBb0/IBmQTGVdg9u5yZYbuAawwSKhlWUzGI1SpNR1RwGmxd9h7XOmr/ LTkSYHmm3qKdTq0gRndE4+FfmxpzdmdDy7kV5Z0FUyEFRDlNYQEvRlVU5ij6TtTLHojupFwygMHmt Y7Ckr4iiCX6X/XtSrD2Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tajed-0000000BMY8-3ucT; Wed, 22 Jan 2025 22:56:59 +0000 Received: from mail-pj1-x102d.google.com ([2607:f8b0:4864:20::102d]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tajea-0000000BMW6-3LNW for linux-riscv@lists.infradead.org; Wed, 22 Jan 2025 22:56:57 +0000 Received: by mail-pj1-x102d.google.com with SMTP id 98e67ed59e1d1-2ee709715d9so490641a91.3 for ; Wed, 22 Jan 2025 14:56:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1737586616; x=1738191416; 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=Fn/PejcoPFKdcNV/yWi5+0DAQFM+nDQKenDgBFYN3Mk=; b=iffupWzawZNxJJ+eUBMzbtxwWRIjp8rGKQtMp8q9zBeGyxo5TEoOvivI8L3UCfPMVR Rb7UzmwMp8UkR90XnGOaYLqUKWMHAJ3BxnM2vv+nmMEe6oWPdTN2twLLfnzyALS5/rjy 30jBz0BOblngVpfquq8XcFLkb49Oj5/4D6If5JnsaOWqsTIq5O+GcDaVz0W3c2mb7+cR YXmBBw4JYfsFSBcrScsocgw5SgDUJ00PWkL9GriKYFLtG3LpH0k9+M//6CWoO1MYW7+D Vfjv0YinsOAT59HaItmx6EE4GvLfnLSdYfLzNKM5kNGc0y75lwDow5TveeWz5QLe1O/V Pg1Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737586616; x=1738191416; 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=Fn/PejcoPFKdcNV/yWi5+0DAQFM+nDQKenDgBFYN3Mk=; b=F6Apq/4dy1GAEH0Ikiqwy/+9/Gn5nX48i0f2pJExcCjjDzaf/KN1DNJs9UR7vNtq/0 S6jdcZwEpKTA84Fypw5MSXcIenM0ygh6jULN+CGUd+U8149UJ+202v1rQEyNg/ahazSB t3cxggU25y51w4dDqEfBp34lPMqXk6L+WOdhv3GfpQ9jLe9VuQvyQI83FUv2rSn7EP/o QJMWprLCCPzLy7enOKHgUa6sYy6foXN5oNpphO2LIieqXzZH3+yoqx1/3yOMu2B45NZZ d/13yDgfJl4C2BsgJAJ0ln3xS0/Q3au0Mm6MC08yUYRUcBnIE9bv5R6kYvEzKqCBWYqC QE/Q== X-Gm-Message-State: AOJu0YyuvP6saVIhSR91dxBL1n3t9AXaKGgulKg9dZt5J/FU5NCozu+Q ChWUTpH8MxSUF3tJQC2HI4f4Wf7J420QA1xGG0lP5ZNm3v5I82Dkdu1BMzZPN1w= X-Gm-Gg: ASbGnctdGmPmLJLBjwFYfCuzQhLtZ3Z8BJA7wHrUz4CE5uNdpzF0t0x06jEojC5ihVJ /C7GykiH6jvSNqhEAZ6TSQZSQTXCoSViNzohJ+wYf4uXQtFZLgtye/4aExrpjwmmfWALTq0NRtN YZQZ3v+s9wHhL8LutJupvITCthiNU4oL8Sd9TH0slTxZd5JuT5mCUaQIfEvEWM68GaDQukLtsFz gos8+YUHFDZxEd7OBL96y4Yh6cmfEYz7uknncydH0Gem7H2jgtx3WuopT/lKvp8wi1PmFc7gtaY dLS05uXm1Q== X-Google-Smtp-Source: AGHT+IGkOWQer0g/4jCDpWuE1nqdG+SGuwiRfCbniIbIL1sny3WjBA7acx7xqTIHE+P8KLoFagnQAg== X-Received: by 2002:a17:90b:5249:b0:2ee:e518:c1cb with SMTP id 98e67ed59e1d1-2f782c4bdd2mr36926987a91.7.1737586615920; Wed, 22 Jan 2025 14:56:55 -0800 (PST) Received: from charlie.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-2f7e6aaf3b4sm2301375a91.25.2025.01.22.14.56.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Jan 2025 14:56:55 -0800 (PST) From: Charlie Jenkins Date: Wed, 22 Jan 2025 14:56:20 -0800 Subject: [PATCH 1/4] riscv: entry: Convert ret_from_fork() to C MIME-Version: 1.0 Message-Id: <20250122-riscv_optimize_entry-v1-1-4ee95559cfd0@rivosinc.com> References: <20250122-riscv_optimize_entry-v1-0-4ee95559cfd0@rivosinc.com> In-Reply-To: <20250122-riscv_optimize_entry-v1-0-4ee95559cfd0@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=3438; i=charlie@rivosinc.com; h=from:subject:message-id; bh=rV9JUhm8W3Bx7rnRIzGCq2bwJctlTEtmatZOhNjH0vc=; b=owGbwMvMwCXWx5hUnlvL8Y3xtFoSQ/rE8s3MIQ08j0o/nwm++ubjMauZxccEN91XPGF74+yfn ewBNxhfdpSyMIhxMciKKbLwXGtgbr2jX3ZUtGwCzBxWJpAhDFycAjCRU7YMf7izZz+fvbMn6Tjb s5lz+eSSgzfZ1B4I++FZYx1kl/riy1xGhpMFnZuYvBcrfshj37l/8YZJ0kmhD5nP2Xm+tzAqnJ4 XwgsA 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-20250122_145656_848632_77C45D20 X-CRM114-Status: GOOD ( 12.06 ) 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..9225c322279aa90e737b1d7144db084319cf8103 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 */ + move a1, s0 /* fn_arg */ + 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; }