From nobody Mon Feb 9 01:45:05 2026 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 46B07EB64D7 for ; Wed, 14 Jun 2023 01:30:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242130AbjFNBav (ORCPT ); Tue, 13 Jun 2023 21:30:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43554 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242103AbjFNBak (ORCPT ); Tue, 13 Jun 2023 21:30:40 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CCB711BFD; Tue, 13 Jun 2023 18:30:31 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 54DC661B47; Wed, 14 Jun 2023 01:30:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4F1C7C433C8; Wed, 14 Jun 2023 01:30:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686706230; bh=iT82mDfcbsJU8gzbcrM/NjkddpYqzVIJB0ER0mXt9RQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=DItFaqVwyVZfghto0Bh8xCeovRtD/Z0suxiTAWh05dXsyaR2dSLivgDymyJm9TiNX i2qiqsszBI+qmJYpHYnRYL+bBiXqqgq9uOyLlxFsqo3OmutVy3syO7RjjX+GPsX9V+ Tr36lIgYuP1sHknpDuBl52E8M63WcYOUT2za6yqxEYoKmC0v3T7jUvPqYWzDtMoIFC 7aLmq22dOSit3DBZMCcKalCkeE+4vRfqo+8bjjbl+x5ujIbvH27HHGu3rsVCEQ2aHL I3QlA5dHTsPv2lQczF4tuWYQ3MPW1lAxOgAkWC9pATWeSPNQvObSVv7kJP4GxHf/df sYPlZjGpYsU1w== From: guoren@kernel.org To: arnd@arndb.de, guoren@kernel.org, palmer@rivosinc.com, conor.dooley@microchip.com, heiko@sntech.de, jszhang@kernel.org, bjorn@kernel.org, cleger@rivosinc.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Guo Ren Subject: [PATCH -next V13 2/3] riscv: stack: Support HAVE_SOFTIRQ_ON_OWN_STACK Date: Tue, 13 Jun 2023 21:30:17 -0400 Message-Id: <20230614013018.2168426-3-guoren@kernel.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20230614013018.2168426-1-guoren@kernel.org> References: <20230614013018.2168426-1-guoren@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Guo Ren Add the HAVE_SOFTIRQ_ON_OWN_STACK feature for the IRQ_STACKS config, and the irq and softirq use the same irq_stack of percpu. Tested-by: Jisheng Zhang Signed-off-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/Kconfig | 6 ++++-- arch/riscv/kernel/irq.c | 35 +++++++++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+), 2 deletions(-) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index a8368fe7be14..f515cb101c19 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -591,11 +591,13 @@ config FPU If you don't know what to do here, say Y. =20 config IRQ_STACKS - bool "Independent irq stacks" if EXPERT + bool "Independent irq & softirq stacks" if EXPERT default y select HAVE_IRQ_EXIT_ON_IRQ_STACK + select HAVE_SOFTIRQ_ON_OWN_STACK help - Add independent irq stacks for percpu to prevent kernel stack overflows. + Add independent irq & softirq stacks for percpu to prevent kernel stack + overflows. We may save some memory footprint by disabling IRQ_STACKS. =20 endmenu # "Platform type" =20 diff --git a/arch/riscv/kernel/irq.c b/arch/riscv/kernel/irq.c index a1dcf8e43b3c..d0577cc6a081 100644 --- a/arch/riscv/kernel/irq.c +++ b/arch/riscv/kernel/irq.c @@ -11,6 +11,9 @@ #include #include #include +#include +#include +#include =20 static struct fwnode_handle *(*__get_intc_node)(void); =20 @@ -56,6 +59,38 @@ static void init_irq_stacks(void) per_cpu(irq_stack_ptr, cpu) =3D per_cpu(irq_stack, cpu); } #endif /* CONFIG_VMAP_STACK */ + +#ifdef CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK +void do_softirq_own_stack(void) +{ +#ifdef CONFIG_IRQ_STACKS + if (on_thread_stack()) { + ulong *sp =3D per_cpu(irq_stack_ptr, smp_processor_id()) + + IRQ_STACK_SIZE/sizeof(ulong); + __asm__ __volatile( + "addi sp, sp, -"RISCV_SZPTR "\n" + REG_S" ra, (sp) \n" + "addi sp, sp, -"RISCV_SZPTR "\n" + REG_S" s0, (sp) \n" + "addi s0, sp, 2*"RISCV_SZPTR "\n" + "move sp, %[sp] \n" + "call __do_softirq \n" + "addi sp, s0, -2*"RISCV_SZPTR"\n" + REG_L" s0, (sp) \n" + "addi sp, sp, "RISCV_SZPTR "\n" + REG_L" ra, (sp) \n" + "addi sp, sp, "RISCV_SZPTR "\n" + : + : [sp] "r" (sp) + : "a0", "a1", "a2", "a3", "a4", "a5", "a6", "a7", + "t0", "t1", "t2", "t3", "t4", "t5", "t6", + "memory"); + } else +#endif + __do_softirq(); +} +#endif /* CONFIG_HAVE_SOFTIRQ_ON_OWN_STACK */ + #else static void init_irq_stacks(void) {} #endif /* CONFIG_IRQ_STACKS */ --=20 2.36.1