From patchwork Fri Aug 30 09:32:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bibo Mao X-Patchwork-Id: 13784805 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 79C23165F05; Fri, 30 Aug 2024 09:32:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=114.242.206.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725010362; cv=none; b=PNCZA0eabQvnz3nthTa7KYm+RY9AtrUSAdtxiJK4fEqSsXrzerQDC9nIlsrLrZuPRFD2IumiFlMAZ5vK3kWpRXN4c2/XqX11GQolUEighJGeAo+QeR+Vr/AkeieNuQh+GHLokFd70zRlwaHQBzDcO69ayL8LwSHl9ocbP4Xed0I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725010362; c=relaxed/simple; bh=MKI/sWHIyLgpfqJt/N3sHA/FKOoAGPohHnYGV6nLDQ0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=KMqPsXAcTpJp/xTNcTPiH6VCz1rGOHE9JOu0hI6Cauvb7i830QZgJQAAhJiYfUfkRfK6MMag5fwOc4CAMoXr5i4sU8wCP0EAVgsOapMXras2hYtr0WykWW+HMk8eFcXI8+3F1/jmcO/PX58oW17Bl1c/jfRyZbDXG5gLMJOiXS8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn; spf=pass smtp.mailfrom=loongson.cn; arc=none smtp.client-ip=114.242.206.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [10.2.5.213]) by gateway (Coremail) with SMTP id _____8AxSZqwkdFmagIlAA--.36703S3; Fri, 30 Aug 2024 17:32:32 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.213]) by front1 (Coremail) with SMTP id qMiowMAxrt6tkdFmizAAAA--.1421S4; Fri, 30 Aug 2024 17:32:31 +0800 (CST) From: Bibo Mao To: Tianrui Zhao , Huacai Chen , Thomas Gleixner Cc: WANG Xuerui , kvm@vger.kernel.org, loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, virtualization@lists.linux.dev, x86@kernel.org, Song Gao Subject: [PATCH v8 2/3] LoongArch: KVM: Implement function kvm_para_has_feature Date: Fri, 30 Aug 2024 17:32:28 +0800 Message-Id: <20240830093229.4088354-3-maobibo@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20240830093229.4088354-1-maobibo@loongson.cn> References: <20240830093229.4088354-1-maobibo@loongson.cn> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: qMiowMAxrt6tkdFmizAAAA--.1421S4 X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/ X-Coremail-Antispam: 1Uk129KBjDUn29KB7ZKAUJUUUUU529EdanIXcx71UUUUU7KY7 ZEXasCq-sGcSsGvfJ3UbIjqfuFe4nvWSU5nxnvy29KBjDU0xBIdaVrnUUvcSsGvfC2Kfnx nUUI43ZEXa7xR_UUUUUUUUU== Function kvm_para_has_feature() is to detect supported paravirt features, it can be used by device driver to detect and enable paravirt features, such as extioi irqchip driver can detect KVM_FEATURE_VIRT_EXTIOI and do some optimization. Signed-off-by: Bibo Mao --- arch/loongarch/include/asm/kvm_para.h | 10 +++++++++ arch/loongarch/kernel/paravirt.c | 31 ++++++++++++++------------- 2 files changed, 26 insertions(+), 15 deletions(-) diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h index 39d7483ab8fd..2174fb53c2e7 100644 --- a/arch/loongarch/include/asm/kvm_para.h +++ b/arch/loongarch/include/asm/kvm_para.h @@ -155,10 +155,20 @@ static __always_inline long kvm_hypercall5(u64 fid, return ret; } +#ifdef CONFIG_PARAVIRT +bool kvm_para_available(void); +unsigned int kvm_arch_para_features(void); +#else +static inline bool kvm_para_available(void) +{ + return false; +} + static inline unsigned int kvm_arch_para_features(void) { return 0; } +#endif static inline unsigned int kvm_arch_para_hints(void) { diff --git a/arch/loongarch/kernel/paravirt.c b/arch/loongarch/kernel/paravirt.c index cc6bf096cb88..dc3cebcb550a 100644 --- a/arch/loongarch/kernel/paravirt.c +++ b/arch/loongarch/kernel/paravirt.c @@ -151,11 +151,14 @@ static void pv_init_ipi(void) } #endif -static bool kvm_para_available(void) +bool kvm_para_available(void) { int config; static int hypervisor_type; + if (!cpu_has_hypervisor) + return false; + if (!hypervisor_type) { config = read_cpucfg(CPUCFG_KVM_SIG); if (!memcmp(&config, KVM_SIGNATURE, 4)) @@ -165,17 +168,21 @@ static bool kvm_para_available(void) return hypervisor_type == HYPERVISOR_KVM; } -int __init pv_ipi_init(void) +unsigned int kvm_arch_para_features(void) { - int feature; + static int feature; - if (!cpu_has_hypervisor) - return 0; if (!kvm_para_available()) return 0; - feature = read_cpucfg(CPUCFG_KVM_FEATURE); - if (!(feature & BIT(KVM_FEATURE_IPI))) + if (!feature) + feature = read_cpucfg(CPUCFG_KVM_FEATURE); + return feature; +} + +int __init pv_ipi_init(void) +{ + if (!kvm_para_has_feature(KVM_FEATURE_IPI)) return 0; #ifdef CONFIG_SMP @@ -258,15 +265,9 @@ static struct notifier_block pv_reboot_nb = { int __init pv_time_init(void) { - int r, feature; - - if (!cpu_has_hypervisor) - return 0; - if (!kvm_para_available()) - return 0; + int r; - feature = read_cpucfg(CPUCFG_KVM_FEATURE); - if (!(feature & BIT(KVM_FEATURE_STEAL_TIME))) + if (!kvm_para_has_feature(KVM_FEATURE_STEAL_TIME)) return 0; has_steal_clock = 1;