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 287D1C4332F for ; Sat, 24 Dec 2022 15:25:03 +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=fDm49razCwmeb6AwMcxhfqmI9Nx7LtDYA1+WXIgAcmY=; b=JoXzymkHGf8TMU Je9eGA6oC2Ne3kJYShuQInfWn/PS+wuJHq8HkYCrdeBVQNt+J3J1mDVBQX3RCiMrPcAkrBLvychJF 3CPRMBonGWQaPyVzc5stzpnM++Oz9KdgOYIJ8lqUo5NvQIV9Iowcp8gxsWpsAVDPZMKNkVwoo44D2 akId8wQN4fqBoLm4QQZZUXjVlSRKOykYQNW8Xigx7cjwlr/xj8h16PfG9wO3STMFf0ghiixWN1KaS 2cAeiKufdPe7/dpoFJmeJexpsxFlaWxsQJysV9R7j422/TLhvsw2ZJroE1EooOX17LOYpWhD634M8 ZGtToZmYJViZxXHHbU2g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p96OI-0014Oj-L9; Sat, 24 Dec 2022 15:24:50 +0000 Received: from mail-lf1-x12e.google.com ([2a00:1450:4864:20::12e]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p930X-00H6wf-Hf for linux-riscv@lists.infradead.org; Sat, 24 Dec 2022 11:48:07 +0000 Received: by mail-lf1-x12e.google.com with SMTP id o6so10206207lfi.5 for ; Sat, 24 Dec 2022 03:48:04 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=ukiode13upAuOopb72PAs48UojpAkxLKmmquZz2y5sU=; b=CCmZ/IJwI00Ym6/4vaJUdJDAH0NB+u9O43/CiR++W3apCv55texUvwzGDjh2fykdeG Sg0+JrLbfmsCFceBLS1Emxu4whItx54t2ZyloSSdXlRDxr0eocdGlbNqim/1f64NArAL q2F2K0CZLplMEWyMEpj4c3vFy4n5NYTBafQWcjJ66kH0NOsK7Wt0HkRQrMRFq6rSbybf ijRCKojxsv9Bvao81xzrf78HOW3hqVCfd+DeF/ZoH+9oSOMVb9Hly5OOEcP0jLRUs/sh u+tS2WdrBu19axEku0ZyFrcxAsQLFBQ9+e8lb5U1oJRs9M8BuLPANy0iJ5/Axgkm9iOH de2A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=ukiode13upAuOopb72PAs48UojpAkxLKmmquZz2y5sU=; b=aFwN3etdmm3pvK617ynUmeoXjv7VAXxLK/ysyxPpD6/orYraFj0qqgXMO43siYL1lo djX3ZFHB9KLQFc3f7VIxIRQFU/9GApYgZGA3dFAvKTVZMeZFWH2yDcrbrCyQkTE42+c+ 06MY4d0BOvTKGiTWDRgLKi/jhdUbJ7ylfPu52ABdZSB4VKqTjm6qpYT8lWQvCOE7mEdE yLUZpbT/CXFPpRTqozwGLFU7cAhsjq6sor0WYDzo+1b22lr92LtgC/yfee4glDKuZnz7 mQNp/dkFwiBSzILKGZq07mUa3F4GbqOQ8pA7gUEXg5NlTQz+S/kCjR+RwmJFwL6CBiZf eB7A== X-Gm-Message-State: AFqh2krVmwATPkTHH267UHRzSzOB2yd3SSDRbaTTtYlnQOq37qLteKqo SAQ/cMfuMT9WwiPNKeOh3sM= X-Google-Smtp-Source: AMrXdXuC+k0Nq4Er3uwrWw4rCEfVQ5kJDFAocYYzKZlNczJGRIr6F3y8NkgjyPFxt/WC96NfWirxmA== X-Received: by 2002:a05:6512:401f:b0:4ab:1cb7:473e with SMTP id br31-20020a056512401f00b004ab1cb7473emr4406661lfb.4.1671882482744; Sat, 24 Dec 2022 03:48:02 -0800 (PST) Received: from curiosity ([5.188.167.245]) by smtp.gmail.com with ESMTPSA id u20-20020a05651220d400b004949f7cbb6esm914420lfr.79.2022.12.24.03.48.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 24 Dec 2022 03:48:01 -0800 (PST) Date: Sat, 24 Dec 2022 14:48:00 +0300 From: Sergey Matyukevich To: "Lad, Prabhakar" Cc: linux-riscv@lists.infradead.org, linux-arch@vger.kernel.org, Anup Patel , Atish Patra , Albert Ou , Palmer Dabbelt , Paul Walmsley , Guo Ren , Alexandre Ghiti , Heiko Stuebner , Sergey Matyukevich , Geert Uytterhoeven , Conor Dooley Subject: Re: [RFC PATCH 1/1] riscv: mm: notify remote harts about mmu cache updates Message-ID: References: <20220829205219.283543-1-geomatsi@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221224_034805_660766_B4CF25C1 X-CRM114-Status: GOOD ( 45.12 ) 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 Hi Prabhakar, > > > > > > > > > > Current implementation of update_mmu_cache function performs local TLB > > > > > > > > > > flush. It does not take into account ASID information. Besides, it does > > > > > > > > > > not take into account other harts currently running the same mm context > > > > > > > > > > or possible migration of the running context to other harts. Meanwhile > > > > > > > > > > TLB flush is not performed for every context switch if ASID support > > > > > > > > > > is enabled. > > > > > > > > > > > > > > > > > > > > Patch [1] proposed to add ASID support to update_mmu_cache to avoid > > > > > > > > > > flushing local TLB entirely. This patch takes into account other > > > > > > > > > > harts currently running the same mm context as well as possible > > > > > > > > > > migration of this context to other harts. > > > > > > > > > > > > > > > > > > > > For this purpose the approach from flush_icache_mm is reused. Remote > > > > > > > > > > harts currently running the same mm context are informed via SBI calls > > > > > > > > > > that they need to flush their local TLBs. All the other harts are marked > > > > > > > > > > as needing a deferred TLB flush when this mm context runs on them. > > > > > > > > > > > > > > > > > > > > [1] https://lore.kernel.org/linux-riscv/20220821013926.8968-1-tjytimi@163.com/ > > > > > > > > > > > > > > > > > > > > Signed-off-by: Sergey Matyukevich > > > > > > > > > > --- > > > > > > > > > > arch/riscv/include/asm/mmu.h | 2 ++ > > > > > > > > > > arch/riscv/include/asm/pgtable.h | 2 +- > > > > > > > > > > arch/riscv/include/asm/tlbflush.h | 18 ++++++++++++++++++ > > > > > > > > > > arch/riscv/mm/context.c | 10 ++++++++++ > > > > > > > > > > arch/riscv/mm/tlbflush.c | 28 +++++++++++----------------- > > > > > > > > > > 5 files changed, 42 insertions(+), 18 deletions(-) > > > > > > > > > > > > > > > > > > > > > > > > > > [ 133.008752] Hardware name: Renesas SMARC EVK based on r9a07g043f01 (DT) > > > > > > > > > [ 133.015338] Call Trace: > > > > > > > > > [ 133.017778] [] dump_backtrace+0x1c/0x24 > > > > > > > > > [ 133.023174] [] show_stack+0x2c/0x38 > > > > > > > > > [ 133.028214] [] dump_stack_lvl+0x3c/0x54 > > > > > > > > > [ 133.033597] [] dump_stack+0x14/0x1c > > > > > > > > > [ 133.038633] [] panic+0x102/0x29a > > > > > > > > > [ 133.043409] [] do_exit+0x704/0x70a > > > > > > > > > [ 133.048362] [] do_group_exit+0x24/0x70 > > > > > > > > > [ 133.053659] [] get_signal+0x68a/0x6dc > > > > > > > > > [ 133.058874] [] do_work_pending+0xd6/0x44e > > > > > > > > > [ 133.064427] [] resume_userspace_slow+0x8/0xa > > > > > > > > > [ 133.070249] ---[ end Kernel panic - not syncing: Attempted to kill > > > > > > > > > init! exitcode=0x0000000b ]--- > > > > > > > > > > > > > > > > > > If I revert this patch [0] bonnie++ works as expected. > > > > > > > > > > > > > > > > > > Any pointers on what could be the issue here? > > > > > > > > > > > > > > > > > > [0] https://git.kernel.org/pub/scm/linux/kernel/git/palmer/linux.git/commit/?h=for-next&id=4bd1d80efb5af640f99157f39b50fb11326ce641 > > > > > > > > > > > > > > > > > > Cheers, > > > > > > > > > Prabhakar > > > > > > > > > > > > > > > > Good catch. Thanks for reporting ! Discussion around the issue and > > > > > > > > possible ways to fix it can be found in the following email thread: > > > > > > > > > > > > > > > > https://lore.kernel.org/linux-riscv/20221111075902.798571-1-guoren@kernel.org/ > > > > > > > > > > > > > > > > Could you please apply the patch from Guo Ren instead of [0] and check > > > > > > > > if you have any issues with your test ? Besides, could you please share > > > > > > > > your kernel configuration and the actual bonnie++ params from emmc_t_002.sh script ? > > > > > > > > > > > > > > > Thanks for the pointer, I'll undo my changes and test Guo's patch. > > > > > > > > > > > > > > I have pasted the script here [0] and attached config. > > > > > > > > > > > > > > [0] https://paste.debian.net/hidden/a7a769b5/ > > > > > > > > > > > > Thanks for the script and config. Could you please also share the > > > > > > following information: > > > > > > - how many cores your system has > > > > > The Renesas RZ/Five SoC has a single Andes AX45MP core. > > > > > > > > > > > - does your system support ASID > > > > > > > > > > > With a quick look at [0] It does support ASID, unless there is a way > > > > > to disable it. > > > > > > > > > > [0] http://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf > > > > > > > > So you have a single-core system, but your kernel configuration enables > > > > CONFIG_SMP. Additional 'deferred TLB flush' logic is dropped at build > > > > time if CONFIG_SMP is disabled. On the other hand, system should not > > > > fail that way even if SMP is enabled. > > > > > > > I enabled CONFIG_SMP while doing some testing of PMA code and indeed > > > enabling this config should not introduce a failure. > > > > > > > Let me double-check if anything can go wrong if cpumasks may have only > > > > a single cpu. Another suspect is a change in update_mmu_cache: probably > > > > making it asid-specific (and thus more granular) was a bad idea. > > > > > > > Thanks. > > > > > > BTW I tested the patch [0] which you pointed out and that fixes the > > > issues seen earlier. > > > > > > [0] https://patchwork.kernel.org/project/linux-riscv/patch/20221111075902.798571-1-guoren@kernel.org/ > > > > All looks good with cpumasks in the single-core case. So deferred TLB > > flush logic is not even executed in your case. So the root cause > > should be in update_mmu_cache change. > > > > May I ask you to repeat the original emmc test on your platform from > > for-next (i.e. with [0] and without [1]) with the following partial revert: > > > > : diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h > > : index ec6fb83349ce..92ec2d9d7273 100644 > > : --- a/arch/riscv/include/asm/pgtable.h > > : +++ b/arch/riscv/include/asm/pgtable.h > > : @@ -415,7 +415,7 @@ static inline void update_mmu_cache(struct vm_area_struct *vma, > > : * Relying on flush_tlb_fix_spurious_fault would suffice, but > > : * the extra traps reduce performance. So, eagerly SFENCE.VMA. > > : */ > > : - flush_tlb_page(vma, address); > > : + local_flush_tlb_page(address); > > : } > > : > > : static inline void update_mmu_cache_pmd(struct vm_area_struct *vma, > > > I tested your above proposed changes and I am no longer seeing an > issue on my platform. Great. I will send a fixup after I double-check on several other hardware platforms. Thanks for testing ! Regards, Sergey _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv