From patchwork Thu Jan 23 19:14:31 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Charlie Jenkins X-Patchwork-Id: 13948572 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 6B2B5C0218B for ; Thu, 23 Jan 2025 19:15:32 +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=XHq+BuNa3GccVeAiiwQ422dZkvZ4rZ2rnunMHYhRB28=; b=2rlHGbb0xY7g3+ iOHhOoGf1k9a98E5pp89nbYcPA6ZubGDZcU7o2cpSuliIcPa4qbXBQukIHiebdA+uSZeguAIwo1Sn aKYhZ64+tsjfyHFarJ7hKwR+81rjsobbugnVzZ7eSzkIagN9G4VE1GTZGMVA08ljFRDFG2KUxCn7V H+vaCMXT1jhVhWMgTmc97BBQwXrOE6ewJeQNvFec2eWYIyzLLlrJ+s1BDTkr9YrjUDldW4xDeH/Ns z/gDyHz3meP9hmFkYFaVU+YzIhHUOnaahDmiCBlyW4SeZuJq1G5ZxXERMOThsKQqZ3gTb1RywX2aK u2xVd1Wy71GCzqNUPPig==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tb2fn-0000000D6gX-1NiL; Thu, 23 Jan 2025 19:15:27 +0000 Received: from mail-pl1-x634.google.com ([2607:f8b0:4864:20::634]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tb2fi-0000000D6dH-3Y41 for linux-riscv@lists.infradead.org; Thu, 23 Jan 2025 19:15:23 +0000 Received: by mail-pl1-x634.google.com with SMTP id d9443c01a7336-21675fd60feso28806935ad.2 for ; Thu, 23 Jan 2025 11:15:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rivosinc-com.20230601.gappssmtp.com; s=20230601; t=1737659722; x=1738264522; 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=7sSJeNFuPfWReO9OO5qkQ/VIRfyi9C57dHefTNmMMUo=; b=RLqSNp0n/+wm7YzZ0ZS759D8oDiadgfLGO2RwAQrhyt4cxh6PPToyA21wCIzkVmxMY GqIHLvjk9xQ6n3mjGcHTNB19SHPymkgOiSg79Q/7iWQG/HZxjAGHJWndSQEUYIt5blOU pYMKG2jAh/GZnPCOMcxo0B4UYIIB566I9o1gweIUwVHBjxsOKraKyc2iN/F9k73654SM Ipg/28CFLvjbwdL3Q5l9TTmw7F6qph1Q7qY34RUTIHYL9Rjt3cnKgZZETsH3kRLVlSeY gho3iZrbEZ064NGr/7rkvLPS8az0UmH5cXVFeuL/KFtec0vur041oaZxyiyg7DoFHRzJ UGkQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1737659722; x=1738264522; 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=7sSJeNFuPfWReO9OO5qkQ/VIRfyi9C57dHefTNmMMUo=; b=KiFLq0Huk9a4o1SilJttiROJavNPmoGYIg3XDqnanu6L6oIQcisOa1oPAm1fYTPxRQ /f8mh+SM7v1t2gOQrYYQVpKz+6hC3xt+Ltxkf75L/QqD6j9cbOqr//wqW/1qTV9DpnA+ X/U/X9ieBQwUtGyXQCWoMYUH13bJ/NLosGCTI3IHmklfRlHsgmZHGswmAbe32+1NdUcZ fgeG427GGONPQx9bjAe+OzrVvw7bY96uLBB9KpMaehWggorp2UTI4TNIU1Ryh0ZGS6NT zQgpvmWIhbNIwPnJQQeMTNvQb/0O1EnqSB9dxbNDn8qkfMMgNo1HR1e2zJPoHwot5Qe1 CKuQ== X-Gm-Message-State: AOJu0YxAjdA2a5BAwR3xtAffIPKduy4mwK526zXEJgFP9JvDqqGOwBBf W9WMoGca7HMny32Z80vX0wkNNvhHxFFWghaPSehxEtvU0yaZ4EqF7yxESnPcXDY= X-Gm-Gg: ASbGncto4w/VrRhDiqche/ooDlNan908fHgtdGWke7WNA8IygNrXeWmWQHLq7/5DGrg otKUNyOXcGMxsf2kxzyKKJ1vj1pO53PZmViajwQBgZ9TUDMWzpY7EiK5KaI23ylNseHZ6rZ2P0o xsPOtaUyMj5HBMYItkZA7WagA+Kkh7V8v2ualePOs8EhIj4sLAPU0bSlfG3Htm4FGopngFwzpUY 0XTvXoHROZfuKSTuHj66wlyM31HqsKo6SHfs/sVeRItW76Qj93OxxwbWh5Btxy0+xZzg6I8IV2p 1ZAYHzOy0oLrNXAKDqqt+D2FaaczvV4= X-Google-Smtp-Source: AGHT+IGwkaQcjsRA0ckQ8hfF7rhnrA97lBFPxRTb5ooMPcRBrFUbh16WviAiYS7cf8KITGLjKjwLug== X-Received: by 2002:a17:902:ec84:b0:215:3661:747e with SMTP id d9443c01a7336-21c353ef81cmr312691415ad.8.1737659722130; Thu, 23 Jan 2025 11:15:22 -0800 (PST) Received: from charlie.ba.rivosinc.com ([64.71.180.162]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-21da3ea3cb2sm2504645ad.90.2025.01.23.11.15.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Jan 2025 11:15:21 -0800 (PST) From: Charlie Jenkins Date: Thu, 23 Jan 2025 11:14:31 -0800 Subject: [PATCH v2 3/4] loongarch: entry: Migrate ret_from_fork() to C MIME-Version: 1.0 Message-Id: <20250123-riscv_optimize_entry-v2-3-7c259492d508@rivosinc.com> References: <20250123-riscv_optimize_entry-v2-0-7c259492d508@rivosinc.com> In-Reply-To: <20250123-riscv_optimize_entry-v2-0-7c259492d508@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=6370; i=charlie@rivosinc.com; h=from:subject:message-id; bh=sOZDk0mqs9t7JThCawDCQVAf1T6D7VObAlzqPEnCu8U=; b=owGbwMvMwCXWx5hUnlvL8Y3xtFoSQ/qkqU42lptFm4tfHG0Q3FL45mrn9VMsDcqfnhfev3Prn tzX2o/fOkpZGMS4GGTFFFl4rjUwt97RLzsqWjYBZg4rE8gQBi5OAZjIqi5Ghv9sVntVJ8m2P4id v3NlbdrVdMcZBxd6sWzOn7uOw19Rdh0jw6Pru85siL8aUHVBPqzbXHn2bCe2E1Lbq09amBWv2m2 8ggkA 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-20250123_111522_884829_65F35166 X-CRM114-Status: GOOD ( 12.05 ) 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 Loongarch is the only architecture that calls syscall_exit_to_user_mode() from asm. Move the call into C so that this function can be inlined across all architectures. Signed-off-by: Charlie Jenkins --- arch/loongarch/include/asm/asm-prototypes.h | 5 +++++ arch/loongarch/include/asm/switch_to.h | 8 +++++++ arch/loongarch/kernel/entry.S | 22 +++++++++---------- arch/loongarch/kernel/process.c | 34 ++++++++++++++++++++++++----- 4 files changed, 51 insertions(+), 18 deletions(-) diff --git a/arch/loongarch/include/asm/asm-prototypes.h b/arch/loongarch/include/asm/asm-prototypes.h index 51f224bcfc654228ae423e9a066b25b35102a5b9..0195d4309fd29f94664d5f34247198c769033b1b 100644 --- a/arch/loongarch/include/asm/asm-prototypes.h +++ b/arch/loongarch/include/asm/asm-prototypes.h @@ -12,3 +12,8 @@ __int128_t __ashlti3(__int128_t a, int b); __int128_t __ashrti3(__int128_t a, int b); __int128_t __lshrti3(__int128_t a, int b); #endif + +asmlinkage void noinstr __no_stack_protector ret_from_kernel_thread(struct task_struct *prev, + struct pt_regs *regs, + int (*fn)(void *), + void *fn_arg); diff --git a/arch/loongarch/include/asm/switch_to.h b/arch/loongarch/include/asm/switch_to.h index 5b225aff3ba21aa06d0713bc8e73e1b941389630..a1c5576f1fd145670e13038bec6dd390486099ab 100644 --- a/arch/loongarch/include/asm/switch_to.h +++ b/arch/loongarch/include/asm/switch_to.h @@ -26,6 +26,14 @@ extern asmlinkage struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *next, struct thread_info *next_ti, void *sched_ra, void *sched_cfa); +void noinstr __no_stack_protector ret_from_kernel_thread(struct task_struct *prev, + struct pt_regs *regs, + int (*fn)(void *), + void *fn_arg); + +void noinstr __no_stack_protector ret_from_fork(struct task_struct *prev, + struct pt_regs *regs); + /* * For newly created kernel threads switch_to() will return to * ret_from_kernel_thread, newly created user threads to ret_from_fork. diff --git a/arch/loongarch/kernel/entry.S b/arch/loongarch/kernel/entry.S index 48e7e34e355e83eae8165957ba2eac05a8bf17df..2abc29e573810e000f2fef4646ddca0dbb80eabe 100644 --- a/arch/loongarch/kernel/entry.S +++ b/arch/loongarch/kernel/entry.S @@ -77,24 +77,22 @@ SYM_CODE_START(handle_syscall) SYM_CODE_END(handle_syscall) _ASM_NOKPROBE(handle_syscall) -SYM_CODE_START(ret_from_fork) +SYM_CODE_START(ret_from_fork_asm) UNWIND_HINT_REGS - bl schedule_tail # a0 = struct task_struct *prev - move a0, sp - bl syscall_exit_to_user_mode + move a1, sp + bl ret_from_fork RESTORE_STATIC RESTORE_SOME RESTORE_SP_AND_RET -SYM_CODE_END(ret_from_fork) +SYM_CODE_END(ret_from_fork_asm) -SYM_CODE_START(ret_from_kernel_thread) +SYM_CODE_START(ret_from_kernel_thread_asm) UNWIND_HINT_REGS - bl schedule_tail # a0 = struct task_struct *prev - move a0, s1 - jirl ra, s0, 0 - move a0, sp - bl syscall_exit_to_user_mode + move a1, sp + move a2, s0 + move a3, s1 + bl ret_from_kernel_thread RESTORE_STATIC RESTORE_SOME RESTORE_SP_AND_RET -SYM_CODE_END(ret_from_kernel_thread) +SYM_CODE_END(ret_from_kernel_thread_asm) diff --git a/arch/loongarch/kernel/process.c b/arch/loongarch/kernel/process.c index 6e58f65455c7ca3eae2e88ed852c8655a6701e5c..16cc949fe43443d70f1d865ce04595c2d8c1615b 100644 --- a/arch/loongarch/kernel/process.c +++ b/arch/loongarch/kernel/process.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include #include @@ -33,6 +34,7 @@ #include #include +#include #include #include #include @@ -47,6 +49,7 @@ #include #include #include +#include #include #include @@ -63,8 +66,9 @@ EXPORT_SYMBOL(__stack_chk_guard); unsigned long boot_option_idle_override = IDLE_NO_OVERRIDE; EXPORT_SYMBOL(boot_option_idle_override); -asmlinkage void ret_from_fork(void); -asmlinkage void ret_from_kernel_thread(void); +asmlinkage void restore_and_ret(void); +asmlinkage void ret_from_fork_asm(void); +asmlinkage void ret_from_kernel_thread_asm(void); void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) { @@ -138,6 +142,24 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) return 0; } +asmlinkage void noinstr __no_stack_protector ret_from_kernel_thread(struct task_struct *prev, + struct pt_regs *regs, + int (*fn)(void *), + void *fn_arg) +{ + schedule_tail(prev); + + fn(fn_arg); + + syscall_exit_to_user_mode(regs); +} + +void noinstr __no_stack_protector ret_from_fork(struct task_struct *prev, struct pt_regs *regs) +{ + schedule_tail(prev); + syscall_exit_to_user_mode(regs); +} + /* * Copy architecture-specific thread state */ @@ -165,8 +187,8 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) p->thread.reg03 = childksp; p->thread.reg23 = (unsigned long)args->fn; p->thread.reg24 = (unsigned long)args->fn_arg; - p->thread.reg01 = (unsigned long)ret_from_kernel_thread; - p->thread.sched_ra = (unsigned long)ret_from_kernel_thread; + p->thread.reg01 = (unsigned long)ret_from_kernel_thread_asm; + p->thread.sched_ra = (unsigned long)ret_from_kernel_thread_asm; memset(childregs, 0, sizeof(struct pt_regs)); childregs->csr_euen = p->thread.csr_euen; childregs->csr_crmd = p->thread.csr_crmd; @@ -182,8 +204,8 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) childregs->regs[3] = usp; p->thread.reg03 = (unsigned long) childregs; - p->thread.reg01 = (unsigned long) ret_from_fork; - p->thread.sched_ra = (unsigned long) ret_from_fork; + p->thread.reg01 = (unsigned long) ret_from_fork_asm; + p->thread.sched_ra = (unsigned long) ret_from_fork_asm; /* * New tasks lose permission to use the fpu. This accelerates context