From patchwork Mon Oct 28 12:10:36 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 11215219 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id ADC811599 for ; Mon, 28 Oct 2019 12:11:04 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 86FA22086D for ; Mon, 28 Oct 2019 12:11:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="UmjqThAV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 86FA22086D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Y7eiY1XVYV0rnCDq94ttBxFsHxFRw9+7FrtSzO2p+PE=; b=UmjqThAVCHtS/P moVPfq/NHz/2CpvnN6m8dhtTp7Mnzp3wBjNXiozvUhDX8llEVTygSb6cGwhEVYnFKqrN8zOYLJ1KB c7KvfzqETl6CxyB7I2Pd2iDUX8pgedovwQ5VLwEC35DJGHPT08Z2HYn2IDsm9UdkgLWSGWSS6uJcH 4HzGp4YryhB8q0gEzNFrOltCdsAZziMnFPfkCL1aBqc2WhdhcUcxtdTbvXxfPHRvIF1hBI0fIKaBr qVv7wJmGzwQ5eGzyLpcO/Jujl4OqgDLQBA4XhHz16AhT3yV7I2BZ4ncB+5JG1mur32TRpxlNwgrIT GJr55rFuNxhM5Idcw+Qw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iP3rT-0006vU-CQ; Mon, 28 Oct 2019 12:11:03 +0000 Received: from [2001:4bb8:18c:c7d:c70:4a89:bc61:2] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1iP3rP-0006kB-Ka; Mon, 28 Oct 2019 12:11:00 +0000 From: Christoph Hellwig To: Palmer Dabbelt , Paul Walmsley Subject: [PATCH 05/12] riscv: implement remote sfence.i using IPIs Date: Mon, 28 Oct 2019 13:10:36 +0100 Message-Id: <20191028121043.22934-6-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191028121043.22934-1-hch@lst.de> References: <20191028121043.22934-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Anup Patel , Damien Le Moal , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org The RISC-V ISA only supports flushing the instruction cache for the local CPU core. Currently we always offload the remote TLB flushing to the SBI, which then issues an IPI under the hoods. But with M-mode we do not have an SBI so we have to do it ourselves. IPI to the other nodes using the existing kernel helpers instead if we have native clint support and thus can IPI directly from the kernel. Signed-off-by: Christoph Hellwig Reviewed-by: Anup Patel --- arch/riscv/include/asm/sbi.h | 3 +++ arch/riscv/mm/cacheflush.c | 24 ++++++++++++++++++------ 2 files changed, 21 insertions(+), 6 deletions(-) diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h index b167af3e7470..0cb74eccc73f 100644 --- a/arch/riscv/include/asm/sbi.h +++ b/arch/riscv/include/asm/sbi.h @@ -94,5 +94,8 @@ static inline void sbi_remote_sfence_vma_asid(const unsigned long *hart_mask, { SBI_CALL_4(SBI_REMOTE_SFENCE_VMA_ASID, hart_mask, start, size, asid); } +#else /* CONFIG_RISCV_SBI */ +/* stub to for code is only reachable under IS_ENABLED(CONFIG_RISCV_SBI): */ +void sbi_remote_fence_i(const unsigned long *hart_mask); #endif /* CONFIG_RISCV_SBI */ #endif /* _ASM_RISCV_SBI_H */ diff --git a/arch/riscv/mm/cacheflush.c b/arch/riscv/mm/cacheflush.c index 3f15938dec89..794c9ab256eb 100644 --- a/arch/riscv/mm/cacheflush.c +++ b/arch/riscv/mm/cacheflush.c @@ -10,9 +10,17 @@ #include +static void ipi_remote_fence_i(void *info) +{ + return local_flush_icache_all(); +} + void flush_icache_all(void) { - sbi_remote_fence_i(NULL); + if (IS_ENABLED(CONFIG_RISCV_SBI)) + sbi_remote_fence_i(NULL); + else + on_each_cpu(ipi_remote_fence_i, NULL, 1); } /* @@ -28,7 +36,7 @@ void flush_icache_all(void) void flush_icache_mm(struct mm_struct *mm, bool local) { unsigned int cpu; - cpumask_t others, hmask, *mask; + cpumask_t others, *mask; preempt_disable(); @@ -46,10 +54,7 @@ void flush_icache_mm(struct mm_struct *mm, bool local) */ cpumask_andnot(&others, mm_cpumask(mm), cpumask_of(cpu)); local |= cpumask_empty(&others); - if (mm != current->active_mm || !local) { - riscv_cpuid_to_hartid_mask(&others, &hmask); - sbi_remote_fence_i(hmask.bits); - } else { + if (mm == current->active_mm && local) { /* * It's assumed that at least one strongly ordered operation is * performed on this hart between setting a hart's cpumask bit @@ -59,6 +64,13 @@ void flush_icache_mm(struct mm_struct *mm, bool local) * with flush_icache_deferred(). */ smp_mb(); + } else if (IS_ENABLED(CONFIG_RISCV_SBI)) { + cpumask_t hartid_mask; + + riscv_cpuid_to_hartid_mask(&others, &hartid_mask); + sbi_remote_fence_i(cpumask_bits(&hartid_mask)); + } else { + on_each_cpu_mask(&others, ipi_remote_fence_i, NULL, 1); } preempt_enable();