From nobody Sun Feb 8 12:42:52 2026 Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1D0C82749C5; Tue, 29 Apr 2025 06:33:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745908407; cv=none; b=LjSWTbZ0NAyxqUNdYbltN6RpXRqOg0ItdYaohfbwgv6KJmNyrlgxSF8ldqtucv/olUeY8TOrWeFGDgTn7CLDR0nKWi6oj2r2q74Ijw4wLNXLEYSY1wRc5YBNZGVchwoIHNXUfwoMXLXjnFUnR+i0boeuDa2DmlEgsD/mXcHwh6s= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745908407; c=relaxed/simple; bh=3iVu7+tTT8Gvmt0QJt/DmkfY+NZPjNaOC/KGL1a8Pmg=; h=Date:From:To:Subject:Cc:In-Reply-To:References:MIME-Version: Message-ID:Content-Type; b=WG44ckYp0zRYdklAA4ql3TZiQy0q9GBPyNGDy79wqS2IXi6fAl2+ffvKk/RbENl4ddnNE3fU3HtN6Gr/FA7djfARl+xr6IwYIYguo7v2BiS1qvE8y4ls49/s8/PhhOMms+Sfl9ZqXr1dHJ2zTEQWWkAfBB2gnHjgEOyhRdDPJSE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=dHI5IqZH; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=HptT/39q; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="dHI5IqZH"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="HptT/39q" Date: Tue, 29 Apr 2025 06:33:23 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1745908404; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eJHm+u5b6jQcx+fXi4PW4N4Y+DdOrABspo9C7Hak+r0=; b=dHI5IqZH+CLgJVQMgjZGTmFIPplghEzDF8GC3kqk6cTBpNpH855uahMpiZ17WZSBZV1Ctd 0McdDjh5+C+uP+4H+A4C8Ys1sftUI6p5uumqs28VoKNrYH4Llv/gA5K6RJyr3iQRtq3QQY S2yjRCiTBQx/gz7Bj4lXQ5GNbIkIss+GsghQlkoOEQd+fKCr1VfZZ4EoXcEdCuwAJlt5TA 9ePA6CLTnG8dQIIfvWdCGfYI3eH1bGd6ttWCovQml56Y/PqXhRUi52nF8ykGWfBT7YEATZ /ymPgrjMPnkt6x7gQ+44KquSLH9Z0J1nNhV3JYfJIcHBkIZa36or+ITi9pCjyg== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1745908404; h=from:from:sender:sender:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eJHm+u5b6jQcx+fXi4PW4N4Y+DdOrABspo9C7Hak+r0=; b=HptT/39qUoSq5Yloohpk22yxmzj2pvRcvMMF7/f1Jrh8NZltPlx5tKa6qsLysB9Uf8QuMn Cy8BRqkl7QPuBIAQ== From: "tip-bot2 for Charlie Jenkins" Sender: tip-bot2@linutronix.de Reply-to: linux-kernel@vger.kernel.org To: linux-tip-commits@vger.kernel.org Subject: [tip: core/entry] riscv: entry: Convert ret_from_fork() to C Cc: Charlie Jenkins , Thomas Gleixner , Alexandre Ghiti , x86@kernel.org, linux-kernel@vger.kernel.org In-Reply-To: <20250320-riscv_optimize_entry-v6-1-63e187e26041@rivosinc.com> References: <20250320-riscv_optimize_entry-v6-1-63e187e26041@rivosinc.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-ID: <174590840374.22196.13222665858567689095.tip-bot2@tip-bot2> Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails Precedence: bulk Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable The following commit has been merged into the core/entry branch of tip: Commit-ID: f955aa8723a65759e920d4de8e5d076cef412afc Gitweb: https://git.kernel.org/tip/f955aa8723a65759e920d4de8e5d076ce= f412afc Author: Charlie Jenkins AuthorDate: Thu, 20 Mar 2025 10:29:21 -07:00 Committer: Thomas Gleixner CommitterDate: Tue, 29 Apr 2025 08:27:10 +02:00 riscv: entry: Convert ret_from_fork() to C Move the main section of ret_from_fork() to C to allow inlining of syscall_exit_to_user_mode(). Signed-off-by: Charlie Jenkins Signed-off-by: Thomas Gleixner Reviewed-by: Alexandre Ghiti Link: https://lore.kernel.org/all/20250320-riscv_optimize_entry-v6-1-63e187= e26041@rivosinc.com --- 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/a= sm/asm-prototypes.h index cd627ec..733ff60 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); =20 +asmlinkage void ret_from_fork(void *fn_arg, int (*fn)(void *), struct pt_r= egs *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 33a5a9f..b2dc5e7 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 =20 -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) =20 #ifdef CONFIG_IRQ_STACKS /* diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 7c244de..7b0a0bf 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -17,7 +17,9 @@ #include #include #include +#include =20 +#include #include #include #include @@ -36,7 +38,7 @@ unsigned long __stack_chk_guard __read_mostly; EXPORT_SYMBOL(__stack_chk_guard); #endif =20 -extern asmlinkage void ret_from_fork(void); +extern asmlinkage void ret_from_fork_asm(void); =20 void noinstr arch_cpu_idle(void) { @@ -206,6 +208,14 @@ int arch_dup_task_struct(struct task_struct *dst, stru= ct task_struct *src) return 0; } =20 +asmlinkage void ret_from_fork(void *fn_arg, int (*fn)(void *), struct pt_r= egs *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 *arg= s) { unsigned long clone_flags =3D args->flags; @@ -242,7 +252,7 @@ int copy_thread(struct task_struct *p, const struct ker= nel_clone_args *args) p->thread.riscv_v_flags =3D 0; if (has_vector() || has_xtheadvector()) riscv_v_thread_alloc(p); - p->thread.ra =3D (unsigned long)ret_from_fork; + p->thread.ra =3D (unsigned long)ret_from_fork_asm; p->thread.sp =3D (unsigned long)childregs; /* kernel sp */ return 0; }