From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED8B9382394; Fri, 27 Mar 2026 11:36:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774611387; cv=none; b=hC8Ywv/a66z9S113sglfoigi9MbsaERnOUwa+QDmkWWM+FZjxPhpoVyOFQWHTRR38RokJUdDDl/xNSRyHLQZAb4dJ2/haCquWFfEJINBBoUVnztKfRenPWwavdkx1XqWbz4jIBBq23jVJKV3xfZr6fbgbqCIBr2xtuQ6jACwuE8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774611387; c=relaxed/simple; bh=JLaNnn4Z96cQuZ+mgviskKs9pjvRxJpA5npZ1PilnT8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=N5K7MPjADW05RZOsSi8NTI7Se3ShmZdNoGuEAIxfWxQIs5Pz2bwcQCLQDK1W9PPfATIO1OXLDjgDkp+r3DPXNaLSQzaZS12IZwRhfQ8Bze3BTM/wSn9W/a86TbO6c/ZyCtr4R63pPMV4r5q+CrYXmvjNtwWza0vMlpwH6e1HfTY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=h1DulSSb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="h1DulSSb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B1FC8C2BC87; Fri, 27 Mar 2026 11:36:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774611386; bh=JLaNnn4Z96cQuZ+mgviskKs9pjvRxJpA5npZ1PilnT8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=h1DulSSbA+vnqnf2XVW7GeXoX4/gyIFkgDhEML58oAQyyhzHasIp1fVFju9X6MrzQ XMwhhvn0DACeb9gWhsKO/MXry46J+9g1B1j0JvTQphRcvHFkPJa6nV/bhhCbN4c0BT CZUjZxopHS9NxCbl/dfcqmIzepUgC6j8Jn+ieD+DzkeOK/9ODcnRCrTxTrk9x4rV5l IFTLbMAIHgM165kWsOCpBYDPu1r98trEfeZgFqQkwaL1MioPYaRCXJpjsRVq5d4gkJ sfSstYq4eaRa9fbx8aFFs2iHO3uOuAm/TEWCMyavDSU3fYU6VQsjODeuJu8ZEg7Pe8 6+uTzJLPDDxQg== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.98.2) (envelope-from ) id 1w65UG-00000006K4a-37HP; Fri, 27 Mar 2026 11:36:24 +0000 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: Joey Gouly , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Will Deacon , Quentin Perret Subject: [PATCH v2 11/30] KVM: arm64: Optimize early exit checks in kvm_s2_fault_pin_pfn() Date: Fri, 27 Mar 2026 11:35:59 +0000 Message-ID: <20260327113618.4051534-12-maz@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20260327113618.4051534-1-maz@kernel.org> References: <20260327113618.4051534-1-maz@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, joey.gouly@arm.com, suzuki.poulose@arm.com, oupton@kernel.org, yuzenghui@huawei.com, tabba@google.com, will@kernel.org, qperret@google.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false From: Fuad Tabba Optimize the early exit checks in kvm_s2_fault_pin_pfn by grouping all error responses under the generic is_error_noslot_pfn check first, avoiding unnecessary branches in the hot path. Reviewed-by: Joey Gouly Signed-off-by: Fuad Tabba Signed-off-by: Marc Zyngier --- arch/arm64/kvm/mmu.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 2b85daaa4426b..0c71e3a9af8b0 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1791,12 +1791,13 @@ static int kvm_s2_fault_pin_pfn(struct kvm_s2_fault *fault) fault->pfn = __kvm_faultin_pfn(fault->memslot, fault->gfn, fault->write_fault ? FOLL_WRITE : 0, &fault->writable, &fault->page); - if (fault->pfn == KVM_PFN_ERR_HWPOISON) { - kvm_send_hwpoison_signal(fault->hva, __ffs(fault->vma_pagesize)); - return 0; - } - if (is_error_noslot_pfn(fault->pfn)) + if (unlikely(is_error_noslot_pfn(fault->pfn))) { + if (fault->pfn == KVM_PFN_ERR_HWPOISON) { + kvm_send_hwpoison_signal(fault->hva, __ffs(fault->vma_pagesize)); + return 0; + } return -EFAULT; + } return 1; } -- 2.47.3