From mboxrd@z Thu Jan 1 00:00:00 1970 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 3E8F1C4332F for ; Mon, 3 Oct 2022 10:39:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229790AbiJCKjH (ORCPT ); Mon, 3 Oct 2022 06:39:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbiJCKi7 (ORCPT ); Mon, 3 Oct 2022 06:38:59 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6F46C1DA74 for ; Mon, 3 Oct 2022 03:38:58 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 29EA8B80F2B for ; Mon, 3 Oct 2022 10:38:57 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A4DD4C433D6; Mon, 3 Oct 2022 10:38:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1664793536; bh=Ge/o7Rp8DcY2sG0HuCr9FZPeFSgyQgALAhESbZPndRM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZaefyPbry2+/5DcwEpVZlyTQfffy/QXFw2DUFzzbsDvxRnGR21S2t/KwZT3ATBXha lxrD1qzQiZoBI8aJJgbfoR6TWckp/KrqnWTZlgRsmWc63P3LmfF2r82uQVcs32F1US tsJk6YBDilccAjDtZeNTwMWavvXFSzcCCEcLTHKkjNzZHetyonpT8rHBoaioUOqUSy rtFQD76heyFpj5nTk8zSGPzKy+eofdjRsaHa0V0du7cBFr8UT+JeaXZ9Dqce6BRNTL tqDJBW1LPZ/ebb9/8wbE3hB1EzyfR4cpUv1iKkuNtCmZ5gF5B/KAsutiYHiZcezC4c rklcZlV5+fvVQ== From: Jisheng Zhang To: Paul Walmsley , Palmer Dabbelt , Albert Ou , Guo Ren Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 2/4] riscv: consolidate ret_from_kernel_thread into ret_from_fork Date: Mon, 3 Oct 2022 18:29:19 +0800 Message-Id: <20221003102921.3973-3-jszhang@kernel.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20221003102921.3973-1-jszhang@kernel.org> References: <20221003102921.3973-1-jszhang@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The ret_from_kernel_thread() behaves similarly with ret_from_fork(), the only difference is whether call the fn(arg) or not, this can be acchieved by testing fn is NULL or not, I.E s0 is 0 or not. Signed-off-by: Jisheng Zhang Acked-by: Guo Ren --- arch/riscv/kernel/entry.S | 11 +++-------- arch/riscv/kernel/process.c | 5 ++--- 2 files changed, 5 insertions(+), 11 deletions(-) diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 39097c1474a0..d227aca7f9d4 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -323,20 +323,15 @@ END(handle_kernel_stack_overflow) ENTRY(ret_from_fork) call schedule_tail - move a0, sp /* pt_regs */ - la ra, ret_from_exception - tail syscall_exit_to_user_mode -ENDPROC(ret_from_fork) - -ENTRY(ret_from_kernel_thread) - call schedule_tail + beqz s0, 1f /* not from kernel thread */ /* Call fn(arg) */ move a0, s1 jalr s0 +1: move a0, sp /* pt_regs */ la ra, ret_from_exception tail syscall_exit_to_user_mode -ENDPROC(ret_from_kernel_thread) +ENDPROC(ret_from_fork) /* diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c index 52002d54b163..fdafed185e21 100644 --- a/arch/riscv/kernel/process.c +++ b/arch/riscv/kernel/process.c @@ -34,7 +34,6 @@ EXPORT_SYMBOL(__stack_chk_guard); #endif extern asmlinkage void ret_from_fork(void); -extern asmlinkage void ret_from_kernel_thread(void); void arch_cpu_idle(void) { @@ -174,7 +173,6 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) /* Supervisor/Machine, irqs on: */ childregs->status = SR_PP | SR_PIE; - p->thread.ra = (unsigned long)ret_from_kernel_thread; p->thread.s[0] = (unsigned long)args->fn; p->thread.s[1] = (unsigned long)args->fn_arg; } else { @@ -184,8 +182,9 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args) if (clone_flags & CLONE_SETTLS) childregs->tp = tls; childregs->a0 = 0; /* Return value of fork() */ - p->thread.ra = (unsigned long)ret_from_fork; + p->thread.s[0] = 0; } + p->thread.ra = (unsigned long)ret_from_fork; p->thread.sp = (unsigned long)childregs; /* kernel sp */ return 0; } -- 2.37.2