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 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 9CE10C38145 for ; Thu, 8 Sep 2022 16:08:42 +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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=IGnWBnd4WiRCMPQg5UFejHAgSulrvYSpWQF94NpgmvQ=; b=0w6ppdkyuqMbAT WtXrOLC2LhqxCX0ReP/YgtRhUuLDp3pii2AgOya7+TKEi81pL5IxnZ9tT9QNCbBXrihg2S1mwd2BU 7AEkBmessewqQQYQv8Hj2l4YqHVsVKNHzgEaHXfA3nciY5GkP9iHeX4jiKvRxTpTHN3KaK2Oc3z/y +wTEVLLm6pRRB63ZDdccV9DdliaCCv9h3S92uzme+4QgFWspiSiRKx9IPkHieEGqBRCT8tZp8I6vn 0fMycpP+Rwh+JpBo1YwCaUzJFY6c1k/8MugzZuCVExZ834oO/mVBXbHdbgiaYQ6MWehz81qsfL+5D Fmp3+uc6OHh7PSl4JJ5A==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oWK4r-005ZWe-CH; Thu, 08 Sep 2022 16:08:29 +0000 Received: from galois.linutronix.de ([2a0a:51c0:0:12e:550::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1oWK4o-005ZVW-Lg for linux-riscv@lists.infradead.org; Thu, 08 Sep 2022 16:08:27 +0000 Date: Thu, 8 Sep 2022 18:08:23 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1662653305; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3melgoxOyPm2WW+MNhQzQQlSABq+pMymGaM5BLeai9A=; b=Gp7zAcq+7nzep4nzUQTlLdgRIUFuc+CYrEawsF2uMxsBS2OCy2xJ6e9vaGHj5Akw1AhABk 1WOEwlsYw+6q/zbB6J46ir2O6l884q5B3EW5aXqiaNGvhko4xkD6wb83FtXsPQqho5nJxS IH9PHxxbCmX4xOycUcdzrelBnit9tcaUOlO3PRfU9JLFgkqgKngO6h9udx5HvJzuwRz+5n S9Dgwelw9WHpk1a2yfx1AOHnMRNEMQA65RwjsuXGRLRcSocegsJlbExOtjw9m9rZT/rhWJ 5A7XVgKn4T3q2+oAKJN/kK2yoU2MViFP0VmKgj/DXxpx/GeydYWqwPIneYOJ+g== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1662653305; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=3melgoxOyPm2WW+MNhQzQQlSABq+pMymGaM5BLeai9A=; b=h8h0ZIYnWSbUEFvLZoVbXhjwdVf0TrAXuHPJieWzTDYNEf6tCIWWlU8leHT7kCHnJxQ6NW T1VaQjp3ssK/XyCQ== From: Sebastian Andrzej Siewior To: guoren@kernel.org Cc: arnd@arndb.de, palmer@rivosinc.com, tglx@linutronix.de, peterz@infradead.org, luto@kernel.org, conor.dooley@microchip.com, heiko@sntech.de, jszhang@kernel.org, lazyparser@gmail.com, falcon@tinylab.org, chenhuacai@kernel.org, apatel@ventanamicro.com, atishp@atishpatra.org, palmer@dabbelt.com, paul.walmsley@sifive.com, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, Guo Ren Subject: Re: [PATCH V4 6/8] riscv: Support HAVE_IRQ_EXIT_ON_IRQ_STACK Message-ID: References: <20220908022506.1275799-1-guoren@kernel.org> <20220908022506.1275799-7-guoren@kernel.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20220908022506.1275799-7-guoren@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220908_090826_871014_F78A5D08 X-CRM114-Status: UNSURE ( 8.40 ) X-CRM114-Notice: Please train this message. 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On 2022-09-07 22:25:04 [-0400], guoren@kernel.org wrote: > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig > index a07bb3b73b5b..a8a12b4ba1a9 100644 > --- a/arch/riscv/Kconfig > +++ b/arch/riscv/Kconfig > @@ -433,6 +433,14 @@ config FPU > > If you don't know what to do here, say Y. > > +config IRQ_STACKS > + bool "Independent irq stacks" > + default y > + select HAVE_IRQ_EXIT_ON_IRQ_STACK > + help > + Add independent irq stacks for percpu to prevent kernel stack overflows. > + We may save some memory footprint by disabling IRQ_STACKS. Do you really think that it is needed to save memory here? Avoiding stack overflows in deep call chains is probably more important than saving ~8KiB per CPU. Sebastian _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv